Evaluation of Canine Retraction Rate in Adult Orthodontic Patients Using Miniscrew-Facilitated Micro-Osteoperforation: A Split-Mouth Randomized Clinical Study

Evaluation of Canine Retraction Rate in Adult Orthodontic Patients Using Miniscrew-Facilitated Micro-Osteoperforation: A Split-Mouth Randomized Clinical Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Evaluation of Canine Retraction Rate in Adult Orthodontic Patients Using Miniscrew-Facilitated Micro-Osteoperforation: A Split-Mouth Randomized Clinical Study Hilary Smith Ojebor, Monica Ndudi Adekoya, Alice Aiewreye Umweni, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6992572/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction: Canine Retraction Rate (CRR) using NiTi closed coil springs may be enhanced by miniscrew-facilitated osteoperforation (MOP). Aims and Objectives: To determine whether MOP significantly accelerates CRR in adults undergoing bilateral first premolar extraction and to evaluate short-term pain levels post-procedure. Study Design: A split-mouth randomized controlled trial with 17 participants (Mean age: 24.9 ± 4.6 years; 64.7% females). Randomization was performed per arch with concealed allocation. Methods On the experimental side, three vertical perforations were created on the buccal cortical plate using a 6 mm × 1.5 mm miniscrew. A 9 mm NiTi closed coil spring delivering 150 g of force facilitated canine retraction. CRR was measured at weeks 1, 8, and 12, and pain levels were assessed at 24 hours, 3-, and 7-days post-MOP using the Wong-Baker FACES Pain Scale. Results The MOP group showed higher mean CRRs (3.6 ± 1.8 mm at week 8, 6.2 ± 1.8 mm at week 12) compared to the control group (2.5 ± 1.5 mm at week 8, 4.7 ± 1.6 mm at week 12). Pain levels at days 3 and 7 post-MOP were significantly higher in the MOP group (p = 0.027 and p = 0.042). Conclusion MOP significantly accelerates canine retraction but increases short-term pain levels. Canine Retraction Rate Miniscrew-facilitated Micro-osteoperforation Split-mouth Study Short-term Pain Levels Canine Retraction Dimensions Orthodontic Tooth Movement Buccal Cortical Plate Perforations Accelerated Orthodontics Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 INTRODUCTION With the growing demand for orthodontic treatment among adult patients, 1 long treatment duration remains a fundamental issue that has become the most important adverse factor affecting the treatment process. 1 , 2 Orthodontic tooth movement (OTM) has been estimated to be 1mm in 4 weeks, putting the average time needed for maxillary canine retraction under maximum anchorage at 7 months and putting total treatment time at about 2 years. 3 The long process which is associated with Orthodontic treatment has prompted many adult patients to accept a less esthetic treatment option like the use of prostheses than orthodontic treatment which is an average of 2 years in duration. 4 Reducing this long duration associated with orthodontic treatment remains a concern for both orthodontists and patients as prolonged treatment time has been associated with not just loss of time but also oral diseases like dental caries, root resorption, 5 gingival inflammation and recession, enamel decalcification. 6 Most important too is the patients’ psychosocial affectation 1 and loss of patients’ cooperation as a result of burnout 4 which can further prolong treatment time. There is still no consensus on the ability of MOP as a procedure to accelerate orthodontic tooth movement thereby shortening treatment time, hence, several researchers have called for the need for more work to be done on MOP to be able to ascertain its effectiveness or non-effectiveness in accelerating tooth movement. Thus, a need for this study. AIMS AND OBJECTIVES To compare the canine retraction rate using NiTi close coil spring alone in canine retraction with that from the use of NiTi close coil spring with adjunctive miniscrew facilitated MOP in adult patients aged 18 years and above undergoing fixed orthodontic treatment To compare canine retraction rate using NiTi close coil spring with one-off application of adjunctive miniscrew facilitated MOP at commencement of canine retraction with canine retraction rate using NiTi close coil spring with repeated application of adjunctive miniscrew facilitated MOP at commencement and 8weeks after commencement of canine retraction in adult patients aged 18years and above undergoing fixed orthodontic treatment. To compare levels of pain and discomfort among adult patients aged 18 years and above undergoing fixed orthodontic treatment in the canine retraction stage using NiTi close coil spring alone with the pain and discomfort levels using closed coil spring with miniscrew facilitated MOPs. METHODOLOGY This is a multistage randomized clinical trial. The first stage of randomization was to allocate intervention i.e., experiment group (EG) either to the right or left with the control i.e., control group (CG) being the opposite side with a 1:1 allocation. The EG was further randomized into one-off MOP (EG 1 ) or twice MOP (EG 2 ) with a 1:1 allocation ratio. The randomization was accomplished by using the permuted random block size of 2 with the random generation function in Excel (Microsoft, Redmond, Wash). Subsequently, the random sequences to either the right or left were concealed in opaque envelopes and shuffled before the intervention to increase the unpredictability of the random allocation sequence. Each patient was asked to pick a sealed envelope to assign the surgical intervention to either the right or left side and another pick to assign the intervention side to group EG 1 or EG 2 . Allocation concealment was done to prevent selection bias and protect the assignment sequence until allocation. Participants Eligibility Criteria Ethical approval was obtained from the University of Benin Teaching Hospital, Benin City Edo State Nigeria with approval number 148260. This trial was also registered at Pactr.org with identifier number PACTR202201662414178. Participants were recruited from new adult patients attending the orthodontic Clinic of the University of Benin Teaching Hospital. Inclusion Criteria Patients aged 18 years, patients who underwent bilateral extraction of the first premolars in either one or both arches, no previous history of fixed orthodontic treatment, no history of systemic disease, bone pathology, or active periodontal disease. Patients who do not use tobacco. Exclusion Criteria Patients on prolonged use of antibiotics, anti-inflammatory drugs, systemic corticosteroids, and calcium channel blockers, poor oral hygiene even after attempts at motivation, patients who had transalveolar extraction of their first premolars, and patients with evidence of active dental caries. Sample Size The formula for comparing means between two groups was used to estimate the sample size for the split-mouth design 7 . Blinding This was ensured only during data collection as blinding of participants and clinicians was not feasible. Intervention Before the commencement of this procedure, informed consent was obtained from all study participants. Accessibility of the area of interest for MOPs was performed as prescribed by Sangsuwon et al. 8 Patients who met inclusion criteria with the following diagnosis: Class I malocclusion cases with moderate to severe crowding Class II malocclusion Class III malocclusion Bimaxillary prognathism And required 2-unit extractions in one or both arches as part of their treatment were recruited. Extractions were carried out 2 weeks before commencing of fixed orthodontic treatment 0.022x0.030 Roth prescription; Dentaurum® brackets were used for all study participants. All teeth were leveled and aligned using various sizes of Nitinol wires. The canine retraction was done on a wire sequence of 0.019x0.025 stainless steel wire placed 4 weeks before commencing canine retraction. A digital periapical radiograph was used to evaluate the bone between the canine and second premolar and to evaluate the root of the canine. Anchorage for canine retraction was done using a 1.8x8mm miniscrew by GDT® inserted buccally between the roots of the first permanent molar and the second premolar bilaterally one week prior to the commencement of canine retraction. Impression of the arch(s) to be used for MOP and control was made using Elvydent® colour changing, normal set, peppermint flavoured, and dust-free alginate material. Casts were produced using type IV Dental stone and then converted to digital models using a three-dimensional (3D) scanner. This was performed using the White Light Scanner (COMET5, 100-200-400, Steinbichler Optotechnik Germany) with 3D reverse modeling software. The distance between the centre of the canine and second premolar brackets was measured as used in a previous study. 9 These landmarks were chosen due to ease of identification. Values obtained are marked as T 0 . This is the baseline distance before the commencement of canine retraction. All measurements in this study were done on digital models obtained from casts using the 3D reverse scanner with modeling software to remove errors due to parallax. The accuracy of the scanner software was verified and confirmed by scanning and measuring 20 randomly selected casts which were rescanned and remeasured one week later Following the method described by Sangsuwon et al. 8 and Sharma et.al 10 MOP was performed at T 0 using orthodontic miniscrews as follows. Patient was asked to rinse with 15 ml of chlorhexidine for 30 seconds The area intended for MOPs following balloting was identified and anaesthetized first with a topical anaesthetic agent and then two minutes later infiltrated using a local anaesthetic agent (0.5ml Zey∞® lidocaine) placed 3mm distally away from the intended MOP site. The tip of a dental explorer was used to prick the attached gingiva around the area anaesthetized to establish that the anaesthesia was sufficient. A sterile GDT® orthodontic miniscrew with a dimension of 6mm x1.5mm attached to a driver was used to make 3 equally spaced vertical perforations of about 2mm apart with the first about apical to the Attached gingiva on the buccal cortical plate on a straight line drawn 3mm parallel to the distal surface of the canine to be retracted by gentle rotational movement of the miniscrew driver with screw attached until the desired depth 6mm was reached. One miniscrew per patient per visit was used to reduce the chances of infection from the procedure. Where bleeding was observed after MOP, gentle pressure using a gauze pack was used to arrest the bleeding. No analgesics were offered after the procedure and all through the duration of the study. Three of the study participants reported severe pain within 24 hours of MOP and were allowed to take 1g of paracetamol. A 9mm NiTi closed coil spring (Sentalloy, 3M Unitek, USA) was used in canine retraction in both the experiment and control side anchored to the head of the miniscrew posteriorly and to the canine hooks on the canine bracket anteriorly. A force of 150g 11 which was produced by 6mm stretching of the springs and was calibrated using Correx guage®. where canine–miniscrew distance was more than the activated coil spring length, ligature wire was used to account for the length disparity by attaching it to the coil spring and secured to the miniscrew to ensure uniform force delivery on coil springs on the right and left quadrant on the same arch. A repeat impression of the arch(s) with MOP was made at weeks 8 and 12 for all patients and casts were converted to digital models. The new distance between the centre of canine and second premolar brackets was measured in T week8 and T week12 . The difference in this new distance T week8 from the baseline (T O ) and T week12 from T 0 is the canine retraction rate in 8 weeks and 12 weeks and marked as T 1 and T 2 respectively. Repeat MOPs were done only for EG 2 patients at 8 weeks from the commencement of retraction to evaluate the effect of repeat MOP application. This is to attempt to sustain the maximum effect of RAP which is believed to start to wane after 2 months. 12 The secondary outcome of this study which was pain and discomfort was measured using the Wong-Baker FACES Pain Rating Scale on 24-hour, 3- and 7-days post-MOP procedures at T 0 for all participants. Study participants were advised not to take any form of pain medication during the study and to notify the investigator when they had severe pain. Reminders were sent electronically, and values were sent electronically on the day. All values obtained were entered into the data collection form for analysis. Canine retraction in this study was the total distance moved by the canine in 12 weeks. Ethical Consideration Before the commencement of this study, approval was obtained from the Health Research Ethics Committee of the University of Benin Teaching Hospital, Benin City with approval number ADM/E22/A/VOL.VII/148260. Also, an informed consent form was administered to every patient who met the inclusion criteria after a thorough explanation of the procedure and its possible advantages and complications for signature in the presence of a witness. Data analysis Data collected was analyzed using SPSS version 23.0 (SPSS Inc., Chicago, Ill). The variables and outcome of the study were described by descriptive statistics using mean, standard deviation (SD), range (minimum-maximum), charts, and tables. Shapiro-Wilk test of normality was used to determine the appropriate parametric and non-parametric tests. Paired samples were used to compare the change in canine retraction over time within CG and EG while independent samples were used to compare the canine retraction rate between CG and EG. A comparison of the canine retraction rate between genders was done using an independent sample. This was also done to compare the maxilla and mandible. The relationship between age and the canine retraction rate was determined using Pearson’s correlation. The pain levels were described using the median and interquartile range; a comparison between the MOP and control group was done using the Mann-Whitney U statistics. All analysis was evaluated with a P ≤ 0.05, considered significant in all cases, at 95% confidence intervals (CI). RESULTS Participant flow The subjects’ ages ranged from 18–33 years (Fig. 1) with a mean age of 24.9 ± 4.6 years and consisted of 11 (64.7%) females and 6 males (35.3%). 29 jaws (14 upper and 15 lower) consisting of 58 quadrants were used in this study. In this study, 18 subjects were recruited into the study. 1 was lost due to loss of anchorage. Out of the 17 subjects who completed the study, 12 had 4-unit extractions constituting 48 quadrants and 5 had 2-unit extractions constituting 10 quadrants. 14 quadrants received one-off MOP with 14 contralateral quadrants as control and 15 quadrants received MOP twice with 15 contralateral quadrants as control. Table I: Sociodemographic Characteristics of the Participants Parameter N (%) Mean Age (in years) ± SD Gender Male 6 (35.3%) 21.9 ± 3.1 Female 11 (64.7%) 26.3 ± 4.6 Total 17 (100.0%) 24.9 ± 4.6 SD = Standard deviation Average Distance Between Mid-Canine Bracket and Mid-2nd Premolar Bracket Table II: Average distance between mid-canine bracket and mid-2nd premolar bracket MOP (T 0 mm) Control (T 0 mm) MOP (T week8 mm) Control (T week8 mm) MOP (T week12 mm) Control (T week12 mm) N 29 29 29 29 29 29 Mean 15.6 15.8 12.0 13.4 9.4 11.1 Std. Deviation 2.5 1.9 2.7 2.2 2.2 2.3 At T 0 , the average distance between the mid-canine bracket and mid-second premolar bracket was 15.6 ± 2.5mm in the MOP group and 15.8 ± 1.9mm in the control group. At T week8 , the average distance was 12.0 ± 2.7mm and 13.4 ± 2.2mm in the MOP and control group respectively. While at T week12 , the average distance was 9.4 ± 2.2mm in the MOP group and 11.1 ± 2.3mm in the control group. The average canine retraction rate increased over time. At both points in time, the average canine retraction was higher in the MOP group (Figure IV). Canine Retraction Rate (Mean Difference) within Experiment and Control Groups at 8 Weeks and 12 Weeks In the MOP group (Table III), the mean canine retraction rate (CRR) was 3.6 ± 1.8mm at week 8, 6.2 ± 1.8mm at week 12 while in the control group, the mean CRR was 2.5 ± 1.5mm at week 8, and 4.7 ± 1.6mm at week 12. The retraction rate (Table 3) at week 8 and week 12 differed significantly from baseline (week 0) in both the MOP (p = 0.000) and control group (p = 0.000). Table III: Canine retraction rate (mean difference) within experiment and control groups at 8 weeks and 12 weeks Group Mean Difference (mm) ± SD T 1 (T0 – T week8 ) p -value T 2 (T0 – T week12 ) p -value N 29 29 MOP 3.6 ± 1.8 0.000** 6.2 ± 1.8 0.000** Control 2.5 ± 1.5 0.000** 4.7 ± 1.6 0.000** T1 = week 8, T2 = week 12, SD = standard deviation ** Significance at the 0.01 level Comparison between the Canine Retraction Rate (CRR) of MOP and the Control Group As shown in Table IV, at week 8 the mean CRR of the MOP group was significantly higher (p = 0.011) than that of the control group by a difference of ≈ 1.1mm (0.3–2.0, 95% CI, p = 0.011). This trend was also observed at week 12; the mean CRR of the MOP group was statistically significantly higher (p = 0.001) than that of the control group by a difference of ≈ 1.5mm (0.6–2.4, 95% CI, p = 0.001). Table IV: Comparison between the Canine Retraction Rate of MOP and Control Group Period MOP Control Mean (mm) ± SD Mean (mm) ± SD Mean Difference (mm) 95% CI p- value N 29 29 T1 3.6 ± 1.8 2.5 ± 1.5 1.1 0.3–2.0 0.011* T2 6.2 ± 1.8 4.7 ± 1.6 1.5 0.6–2.4 0.001* T1 = CRR at week 8, T2 = CRR at week 12, SD = Standard Deviation, CI = Confidence Interval * Significance at the 0.05 level ** Significance at the 0.01 level Canine Retraction Rate Based on the Number of MOP Appointments At weeks 8 and 12, as shown in Table V, the average CRR was slightly higher in participants who had twice MOP applications when compared to those who had one-off MOP application although the difference was not statistically significant at the various time intervals (p > 0.05 in both cases). Table V: Canine retraction rate of the MOP group based on the number of MOP appointments Period NA = 1 NA = 2 Mean (mm) ± SD Mean (mm) ± SD Mean Difference (mm) 95% CI p- value N 14 15 T 1 3.2 ± 1.3 4.0 ± 2.2 -0.8 -2.1–2.0 0.011* T 2 6.1 ± 1.9 6.3 ± 1.6 -0.2 -1.6–2.4 0.001* T 1 = week 8, T 2 = week 12, SD = standard deviation, CI = confidence interval Gender and Canine Retraction Rate (CRR) in Experiment and Control Groups In the MOP group, the mean CRR was higher in males across the time periods although the difference was only statistically significant at week 12 (p = 0.020). In the control group, the mean CRRs of males were slightly higher than that of females but not significant at week 8 (p = 0.353) as well as at week 12 (p = 0.357). Table VI: Canine retraction rate based on gender Time Male Mean ± SD Female Mean ± SD MD (mm) 95% CI p- value MOP T 1 4.0 ± 1.5 3.4 ± 2.0 0.6 -0.9–2.1 0.390 T 2 7.3 ± 1.6 5.7 ± 1.7 1.6 0.3–2.9 0.020 * Control T 1 2.8 ± 1.7 2.3 ± 1.4 0.5 -0.6 -1.8 0.353 T 2 5.1 ± 1.7 4.5 ± 1.5 0.6 -0.7–1.9 0.357 T 1 = week 8, T 2 = week 12, SD = standard deviation, MD = mean difference * Significance at the 0.05 level Age and Canine Retraction Rate Figure V below shows the correlation between the age of the subjects and the canine retraction rate in both the MOP and control group. At week 8 (T 1 ), there was no relationship between age and canine retraction rate in both groups. However, at week 12 (T 2 ), in the MOP group there was a significant negative relationship (r = -0.49, p = 0.007) between age and canine retraction (retraction decreased as age increased). Assessment and Comparison of the Level of Pain between the Experiment and Control Groups The level of pain recorded in the groups is shown in the plot below (Fig. VI). In the MOP group, the median pain level was 6.0 (4.0–8.0) on day 1, 4.0 (2.0–5.0) on day 3 and 1.0 (0.0 − 2.0) on day 7. In the control group, the median pain level was 5.0 (4.0–6.0) on day 1, 3.0 (1.0– 4.0) on day 3, and 0.0 (0.0–1.0) on day 7. In both groups, there was a significant reduction in the level of pain as the days increased (p = 0.000, in both groups). Comparison between the Pain Level of MOP and the Control Group Between the experiment (MOP) and control groups, as shown in Table VII, the distribution of pain levels was not the same but the difference was not statistically significant at 24 hours post-procedure (p = 0.094) while at day 3 and day 7, the pain levels differences of the MOP group was statistically significant than that of the control (p = 0.027 and p = 0.042 respectively). In the MOP group, there was no significant difference in the distribution of pain from the control group at day 1 (24 hours) (p > 0.05) but there was a significant difference in the distribution of pain at day 3 (p = 0.030) and day 7 (p = 0.040). Table VII: Comparison between the pain level of MOP and control group MOP (N = 29) Control (N = 29) Median (IQR) Median (IQR) p- value Day 1 6.0 (4.0–8.0) 5.0 (4.0–6.0) 0.094 Day 3 4.0 (2.0–5.0) 3.0 (1.0–4.0) 0.027* Day 7 1.0 (0.0–2.0) 0.0 (0.0–1.0) 0.042* IQR = Inter-quartile range * Significance at the 0.05 level DISCUSSION The daunting task of reducing the treatment duration 13 as well as its accompanying undesirable side effects associated with prolonged treatment time in fixed orthodontic treatment in general and among adult patients in particular, has led to the introduction of new treatment modalities such as MOP. 14 This split-mouth study design helped reduce the biological variability as each subject served as its control. Homogenous subjects (young adult patients) were as much as possible used in this study. This allowed for similar inflammatory responses to MOP based on their close age range. Cofounders were eliminated using the inclusion criteria. 15 This study conducted to determine CRR using a NiTi close coil spring with MOP on the experiment side and NiTi close coil spring only on the control side produced a mean retraction rate of 6.2 ± 1.8mm from the experiment sides and 4.7 ± 1.6mm from the control sides at the end of 12weeks of retraction. This finding was significantly higher on the experiment side which had a NiTi close coil spring with MOPs applied when compared with that on the control side which had a NiTi close coil spring only. This result has been attributed to the RAP elicited by the micro-traumatic nature of MOP which translates into an increase in inflammatory markers and osteoclastic activity which is the hallmark of OTM. 16 The finding from this study which showed about 1.34 times faster CRR is in keeping with reports from other studies like that by Zoya Ahsan et.al 17 which had 30 participants and reported a 1.6 times faster retraction rate. Other studies have reported even higher values of a 2.3 times faster retraction rate 9 . Studies that have shown no difference in CRR following MOP application also exist in the literature with Alkebsi et.al reporting no difference whatsoever in retraction rate. 18 , 19 One of the popularized distinctive advantages of MOP placement is the repeatability of the procedure as opposed to the other highly invasive surgical-assisted techniques. This repeat application is believed to cause a constant circulation of inflammatory chemokines and cytokines within the localized region where MOP is applied thus leading to sustained increase in localized alveolar bone turnover. 20 , 21 Wilcko et.al reported that RAP takes effect in 1 or 2 days following the surgical intervention and reaches its peak levels in about one 1 or 2 months and then starts to wane, 12 repeats of MOP in a subset of the experimental sides in this study were planned for 8 weeks from the time of commencing this study. There was no significant increase in CRR when MOP was repeated 8 weeks after study commencement in the subset within the experiment group. This finding agrees with that reported in another study where there was no increase in OTM with 4 weekly applications of MOP in the course for 3 months. 22 , 23 Our finding may have been due to a decrease in the force in the NiTi close coil spring as the distance between the canine and the second premolar decreases as the coil activation was done just once at the beginning of the study. However, a study from Attri et.al reported a significant increase in retraction rate and faster space closure when MOPs were repeatedly applied every 28 days over 3 months. 20 Attri et.al had six MOPs repeatedly applied to both the mesial and distal aspects of the alveolar bone of the canines to the retracted. This may have produced more RAP effect leading to an increase in OTM. 20 Therefore, there may be a need to evaluate force reactivation with repeat MOP application, the number and points of application of the repeated MOPs, and where possible depth of MOP applied to be able to sufficiently state whether repeat MOP are effective or ineffective. Although studies have reported no increase in OTM following MOP whether at the beginning of the study or with repeated application the authors postulate that the RAP elicited by MOP is so small that that the biological response is minimal. 22 The average rate of tooth movement by conventional orthodontics is estimated to be around 0.8 to 1.2 mm/month when continuous forces are being applied. 24 was observed to be less than that derived from this study in both the control and experiment sides with values of 1-2.6mm/month. This observation may have been a result of the differences in the form of anchorage used. This study used absolute anchorage in the form of TADs. This is also true when compared to other studies on canine retraction rates published by Dixon et al 25 who observed that the rate of canine retraction with NiTi closed coil springs was 0.81 mm/month and Cacciafesta et al 26 who reported a 1.1 mm/month canine movement but did not use absolute anchorage. Therefore, absolute anchorage should be considered where possible if a faster OTM is desired. This eliminates anchorage loss and invariably reduces OTM associated with other forms of anchorage design. On the secondary outcome of our study which was pain and discomfort, the highest values of pain scores were recorded on day one in both the control and experimental side. This can easily be attributed to the force effect on the periodontium of the canines by the NiTi close coil spring. The pain perception of the study participants from the experiment quadrants when compared to that from the control quadrants was statistically not significant 24 hours post MOP application but was statistically significant at day 3 and day 7 post MOP application. Even though there was a decrease in pain reported from both the experiment and control sides as the number of days post-MOP increased, the pain levels on the experiment sides were higher at day 3 and day 7. This can be a result of the microtrauma associated with MOP both to the mucosa and the underlying alveolar bone and or lack of blinding in the application of MOP to the experiment quadrants in this study. Our study had 11 females and 6 males with three of the female study participants reporting severe pain before 24 hours post-MOP application with all three requiring a single dose of Paracetamol 1g for their pain. Some other studies have not only shown more pain experience on the experiment quadrants but have also reported adverse effects on patients’ quality of life. 22 Other complications associated with MOP administration which even though not reported in the results were observed was rotation/ tipping of the canines. This was observed in both the experiment and control mouth sides despite the use of 0.19 x 0.025 stainless steel wire placed 4 weeks before commencement of retraction and throughout retraction. The direction of force application could have accounted for this finding. Canine root resorption which is also an associated MOP complication was equally assessed by comparing digital periapical radiographs taken at zero week and 12th week of this study with no form of resorption observed after 12 weeks. A reduction in time of about 2.9 weeks was observed from this study in the canine retraction phase of fixed orthodontic treatment. This may not still be significant as the overall reduction in orthodontic treatment time. Therefore, MOP applicability in other stages of orthodontic treatment must be equally evaluated if an appreciable reduction in total treatment time is desired which will improve its acceptance by both patients and clinicians. CONCLUSION From this study, the canine retraction rate using a NiTi close coil spring with adjunctive miniscrew facilitated MOP was significantly higher than that from the use of a NiTi close coil spring alone. Also, the canine retraction rate using NiTi close coil spring with twice application of adjunctive miniscrew facilitated MOP at the commencement of retraction and 8 weeks afterward did not produce a significantly faster retraction rate when compared to once the application of MOP at the commencement of canine retraction. Pain from the administration of adjunctive MOP to NiTi close coil spring activation in canine retraction even though was not statistically significant 24 hours post-administration from pain from NiTi close coil activation alone, pain from the former was significantly higher than pain from the later by day 3 and day 7 post-MOP administration. Declarations CONFLICTS OF INTEREST All authors declare no conflicts of interest related to this study. The research was conducted independently, without financial or personal relationships that could inappropriately influence or bias our findings. All materials and equipment used in this study were obtained through standard procurement channels, and no external funding or sponsorship was received. AUTHORS Hilary Smith Ojebor 1 , Monica Ndudi Adekoya 1 , Alice Aiewreye Umweni 2, 3 , Clement Chinedu Azodo 4,5 , Godwin Obi Bassey 5 , Nonso Emmanuel Onyia 6 1 University of Calabar, Calabar, Nigeria, Department of Child Dental Health 2 University of Benin Teaching Hospital, Benin City, Nigeria, Department of Orthodontics 3 University of Benin, Benin City, Nigeria, Department of Orthodontics 4 University of Benin, Benin City, Nigeria, Department of Periodontics 5 University of Benin Teaching Hospital, Benin City, Nigeria, Department of Periodontics 6 University of Calabar, Calabar, Nigeria, Department of Oral Medicine/Oral Pathology Corresponding Author Details Name : Godwin Obi Bassey Email : [email protected] FUNDING No external funding was provided for this study. All funding was provided by the authors. TRIAL REGISTRATION DETAILS Registry 1: University of Benin Teaching Hospital, Benin City Edo State, Nigeria Registration number: 148260 Registration date: 9 Jan 2020 Registry 2: Pactr.org Registration number: PACTR202201662414178 Registration date: 24 Jan 2022 CONSENT TO PUBLISH DECLARATION Not applicable as study does not contain any identifying information of study participants. Author Contribution H.S. was the primary researcher and carried out data collection, and in combination with G.O., wrote and edited the main manuscript text. M.N., A.A., and C.C. were the supervisors and participated in the study conception/design and data interpretation process. N.E. assisted in data collection and analysis. All Authors reviewed the manuscript. References Nimeri G, Kau CH, Abou-Kheir NS, Corona R. Acceleration of tooth movement during orthodontic treatment-a frontier in orthodontics. Prog Orthod . 2013; 14:1-8. Mavreas D, Athanasiou AE. Factors affecting the duration of orthodontic treatment: a systematic review. The European Journal of Orthodontics . 2008;30(4):386-395. Pilon JJGM, Kuijpers-Jagtman AM, Maltha JC. Magnitude of orthodontic forces and rate of bodily tooth movement. An experimental study. American Journal of Orthodontics and Dentofacial Orthopedics . 1996;110(1):16-23. Skidmore KJ, Brook KJ, Thomson WM, Harding WJ. Factors influencing treatment time in orthodontic patients. American Journal of Orthodontics and Dentofacial Orthopedics . 2006;129(2):230-238. Apajalahti S, Peltola JS. Apical root resorption after orthodontic treatment—a retrospective study. The European Journal of Orthodontics . 2007;29(4):408-12. Diamanti‐Kipioti A, Gusberti FA, Lang NP. Clinical and microbiological effects of fixed orthodontic appliances. J Clin Periodontol . 1987;14(6):326-33. Pandis N. Sample calculation for split-mouth designs. American journal of orthodontics and dentofacial orthopedics . 2012;141(6):818-9. Sangsuwon C, Alansari S, Nervina J, Teixeira CC, Alikhani M. Micro-osteoperforations in accelerated orthodontics. Clinical Dentistry Reviewed . 2018; 2:1-10. Feizbakhsh M, Zandian D, Heidarpour M, Farhad SZ, Fallahi HR. The use of micro-osteoperforation concept for accelerating differential tooth movement. J World Fed Orthod . 2018;7(2):56-60. Sharma K, Batra P, Sonar S, Srivastava A, Raghavan S. Periodontically accelerated orthodontic tooth movement: a narrative review. J Indian Soc Periodontol . 2019;23(1):5-11. Sukurica Y, Karaman A, Gürel HG, Dolanmaz D. Rapid canine distalization through segmental alveolar distraction osteogenesis. Angle Orthod . 2007;77(2):226-36. Wilcko MT, Wilcko WM, Pulver JJ, Bissada NF, Bouquot JE. Accelerated osteogenic orthodontics technique: a 1-stage surgically facilitated rapid orthodontic technique with alveolar augmentation. Journal of oral and maxillofacial surgery . 2009;67(10):2149-59. Safir NK, Athar S, Prashantha GS. Acceleratory orthodontics-the race against time. Journal of Dental and Orofacial Research . 2018;14(2):80-7. Nicozisis JL. Accelerated orthodontics through micro-osteoperforation. Orthodontic Practice US . 2013;4(3):56-7. Giannopoulou C, Dudic A, Pandis N, Kiliaridis S. Slow and fast orthodontic tooth movement: an experimental study on humans. Eur J Orthod . 2016;38(4):404-8. Al-Khalifa KS, Baeshen HA. Micro-osteoperforations and its effect on the rate of tooth movement: a systematic review. Eur J Dent . 2021;15(01):158-167. Ahsan Z, Khan M, Jan A, Shah TI, Naeem S. The use of micro-osteoperforation concept for accelerating differential tooth movement. Pakistan Armed Forces Medical Journal . 2021;71(3):844-8. Alkebsi A, Al-Maaitah E, Al-Shorman H, Alhaija EA. Three-dimensional assessment of the effect of micro-osteoperforations on the rate of tooth movement during canine retraction in adults with Class II malocclusion: a randomized controlled clinical trial. American Journal of Orthodontics and Dentofacial Orthopedics . 2018;153(6):771-85. Aboalnaga AA, Salah Fayed MM, El-Ashmawi NA, Soliman SA. Effect of micro-osteoperforation on the rate of canine retraction: a split-mouth randomized controlled trial. Prog Orthod . 2019; 20:1-9. Attri S, Mittal R, Batra P, et al. Comparison of rate of tooth movement and pain perception during accelerated tooth movement associated with conventional fixed appliances with micro-osteoperforations–a randomised controlled trial. J Orthod . 2018;45(4):225-33. Abdelhameed AN, Refai WMM. Evaluation of the effect of combined low energy laser application and micro-osteoperforations versus the effect of application of each technique separately on the rate of orthodontic tooth movement. Open Access Maced J Med Sci . 2018;6(11):2180. Fattori L, Sendyk M, de Paiva JB, Normando D, Neto JR. Micro-osteoperforation effectiveness on tooth movement rate and impact on oral health related quality of life: a randomized clinical trial. Angle Orthod . 2020;90(5):640-7. Cramer CL, Campbell PM, Opperman LA, Tadlock LP, Buschang PH. Effects of micro-osteoperforations on tooth movement and bone in the beagle maxilla. American Journal of Orthodontics and Dentofacial Orthopedics . 2019;155(5):681-92. Sugimori T, Yamaguchi M, Shimizu M, et al. Micro-osteoperforations accelerate orthodontic tooth movement by stimulating periodontal ligament cell cycles. American Journal of Orthodontics and Dentofacial Orthopedics . 2018;154(6):788-96. Dixon V, Read MJF, O’brien KD, Worthington H V, Mandall NA. A randomized clinical trial to compare three methods of orthodontic space closure. J Orthod . 2002;29(1):31-6. Cacciafesta V, Sfondrini MF, Ricciardi A, Scribante A, Klersy C, Auricchio F. Evaluation of friction of stainless steel and esthetic self-ligating brackets in various bracket-archwire combinations. American Journal of Orthodontics and Dentofacial Orthopedics . 2003;124(4):395-402. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6992572","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":485975267,"identity":"60210fa4-ff4c-4a61-8222-fbffdd8228b2","order_by":0,"name":"Hilary Smith Ojebor","email":"","orcid":"","institution":"University of Calabar","correspondingAuthor":false,"prefix":"","firstName":"Hilary","middleName":"Smith","lastName":"Ojebor","suffix":""},{"id":485975268,"identity":"5a2810e0-fb7f-41d6-8620-a9fa50d7c50d","order_by":1,"name":"Monica Ndudi Adekoya","email":"","orcid":"","institution":"University of Calabar","correspondingAuthor":false,"prefix":"","firstName":"Monica","middleName":"Ndudi","lastName":"Adekoya","suffix":""},{"id":485975269,"identity":"4b4f18a3-d195-4c5a-8402-864869900ada","order_by":2,"name":"Alice Aiewreye Umweni","email":"","orcid":"","institution":"University of Benin Teaching Hospital","correspondingAuthor":false,"prefix":"","firstName":"Alice","middleName":"Aiewreye","lastName":"Umweni","suffix":""},{"id":485975270,"identity":"6e10e833-cfe9-485a-9e1f-e1cd2ed72aed","order_by":3,"name":"Clement Chinedu Azodo","email":"","orcid":"","institution":"University of Benin","correspondingAuthor":false,"prefix":"","firstName":"Clement","middleName":"Chinedu","lastName":"Azodo","suffix":""},{"id":485975271,"identity":"58cdc130-7211-4e46-853f-5e4de645f2e9","order_by":4,"name":"Godwin Obi Bassey","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/ElEQVRIiWNgGAWjYHACA4YEBoYENgkITw5EHHhAihZjsJYEQlqAIIEBqiWxAcLFDeTdm7dJPNxhk8cn3fz444+Kw+nzww4/BNpiJ6fbgF2L4ZljZRKJZ9KK2WSOmUnznDmcu/F2mgFQS7Kx2QEcWmbkmN1IbDuc2CaRYMbM2AbUMjsBpOVA4jbCWtI/f/z573C64ez0D3i1yEvAteQYSPA2HE6Ql87Bb4sBz7HyH4ltIL+cKZPmOZZuuEE6p+BAggFuv8i3N282/Nlmkyc/u33zxx811vLys9M3f/hQYSeHS4sBmngzVMQAu3KwLQ2o/DoMkVEwCkbBKBgFAD8HZ/IutXCqAAAAAElFTkSuQmCC","orcid":"","institution":"University of Benin Teaching Hospital","correspondingAuthor":true,"prefix":"","firstName":"Godwin","middleName":"Obi","lastName":"Bassey","suffix":""},{"id":485975272,"identity":"3c642662-810f-4909-8aaa-dc60c8cd5e91","order_by":5,"name":"Nonso Emmanuel Onyia","email":"","orcid":"","institution":"University of Calabar","correspondingAuthor":false,"prefix":"","firstName":"Nonso","middleName":"Emmanuel","lastName":"Onyia","suffix":""}],"badges":[],"createdAt":"2025-06-27 14:38:05","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6992572/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6992572/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":87036757,"identity":"f20070e9-3aac-4a14-bf92-f5bdaff49a14","added_by":"auto","created_at":"2025-07-18 13:22:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":414624,"visible":true,"origin":"","legend":"\u003cp\u003eFigure I: Clinical picture showing 3 bleeding spots following MOP application\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/5ca656539f7882ea2d6d0f03.png"},{"id":87036759,"identity":"df8b813d-032e-462a-8708-a0e3c2eda932","added_by":"auto","created_at":"2025-07-18 13:22:02","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":501888,"visible":true,"origin":"","legend":"\u003cp\u003eFigure II: Photograph showing measurement digital measurement of space between the mid canine and second premolar bracket\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/1aef9a870304b369725e83e0.png"},{"id":87036766,"identity":"84bd0181-06ae-445e-a1ed-82df133c5900","added_by":"auto","created_at":"2025-07-18 13:22:02","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":142140,"visible":true,"origin":"","legend":"\u003cp\u003eFigure III: Flowchart showing selection, randomization, allocation, follow-up and analysis procedures\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/7abd75f41eaf515a765c0cd5.png"},{"id":87036756,"identity":"104fa09a-409b-4fd7-8dd8-7b94f3809d4f","added_by":"auto","created_at":"2025-07-18 13:22:02","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":28669,"visible":true,"origin":"","legend":"\u003cp\u003eFigure IV: The mean ± 1 standard deviation (error bar) of canine retraction rate across the periods, T1 (week 8) and T2 (week 12) in the MOP and Control\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/9b41836b27c31f47da9586be.png"},{"id":87038550,"identity":"9f6ee5dc-ec74-4837-b92c-1068d2c32797","added_by":"auto","created_at":"2025-07-18 13:30:02","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":53457,"visible":true,"origin":"","legend":"\u003cp\u003eFigure V: Age and Canine Retraction Rate\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/849507422798fa99d5296a58.png"},{"id":87038548,"identity":"d108aade-be24-413f-b208-d4faae283f0b","added_by":"auto","created_at":"2025-07-18 13:30:02","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":15547,"visible":true,"origin":"","legend":"\u003cp\u003eFigure VI: Box plot showing the level of pain in the groups across the 3 time periods\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/1857b68ac0f5fab2a57da6f6.png"},{"id":87282909,"identity":"c484394f-0142-49e8-b8cf-94a09c0bf4ae","added_by":"auto","created_at":"2025-07-22 10:02:06","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2540565,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6992572/v1/4901cc39-e70b-4bfe-ba78-50c9c060909f.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eEvaluation of Canine Retraction Rate in Adult Orthodontic Patients Using Miniscrew-Facilitated Micro-Osteoperforation: A Split-Mouth Randomized Clinical Study\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eWith the growing demand for orthodontic treatment among adult patients,\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e long treatment duration remains a fundamental issue that has become the most important adverse factor affecting the treatment process.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e Orthodontic tooth movement (OTM) has been estimated to be 1mm in 4 weeks, putting the average time needed for maxillary canine retraction under maximum anchorage at 7 months and putting total treatment time at about 2 years.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e The long process which is associated with Orthodontic treatment has prompted many adult patients to accept a less esthetic treatment option like the use of prostheses than orthodontic treatment which is an average of 2 years in duration.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eReducing this long duration associated with orthodontic treatment remains a concern for both orthodontists and patients as prolonged treatment time has been associated with not just loss of time but also oral diseases like dental caries, root resorption,\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e gingival inflammation and recession, enamel decalcification.\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e Most important too is the patients’ psychosocial affectation\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e and loss of patients’ cooperation as a result of burnout\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e which can further prolong treatment time.\u003c/p\u003e\u003cp\u003eThere is still no consensus on the ability of MOP as a procedure to accelerate orthodontic tooth movement thereby shortening treatment time, hence, several researchers have called for the need for more work to be done on MOP to be able to ascertain its effectiveness or non-effectiveness in accelerating tooth movement. Thus, a need for this study.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cdiv id=\"Sec2\" class=\"Section2\"\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"AIMS AND OBJECTIVES","content":"\u003cul\u003e\u003cli\u003e\u003cp\u003eTo compare the canine retraction rate using NiTi close coil spring alone in canine retraction with that from the use of NiTi close coil spring with adjunctive miniscrew facilitated MOP in adult patients aged 18 years and above undergoing fixed orthodontic treatment\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eTo compare canine retraction rate using NiTi close coil spring with one-off application of adjunctive miniscrew facilitated MOP at commencement of canine retraction with canine retraction rate using NiTi close coil spring with repeated application of adjunctive miniscrew facilitated MOP at commencement and 8weeks after commencement of canine retraction in adult patients aged 18years and above undergoing fixed orthodontic treatment.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eTo compare levels of pain and discomfort among adult patients aged 18 years and above undergoing fixed orthodontic treatment in the canine retraction stage using NiTi close coil spring alone with the pain and discomfort levels using closed coil spring with miniscrew facilitated MOPs.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e"},{"header":"METHODOLOGY","content":"\u003cp\u003eThis is a multistage randomized clinical trial. The first stage of randomization was to allocate intervention i.e., experiment group (EG) either to the right or left with the control i.e., control group (CG) being the opposite side with a 1:1 allocation. The EG was further randomized into one-off MOP (EG\u003csub\u003e1\u003c/sub\u003e) or twice MOP (EG\u003csub\u003e2\u003c/sub\u003e) with a 1:1 allocation ratio. The randomization was accomplished by using the permuted random block size of 2 with the random generation function in Excel (Microsoft, Redmond, Wash).\u003c/p\u003e\u003cp\u003eSubsequently, the random sequences to either the right or left were concealed in opaque envelopes and shuffled before the intervention to increase the unpredictability of the random allocation sequence. Each patient was asked to pick a sealed envelope to assign the surgical intervention to either the right or left side and another pick to assign the intervention side to group EG\u003csub\u003e1\u003c/sub\u003e or EG\u003csub\u003e2\u003c/sub\u003e. Allocation concealment was done to prevent selection bias and protect the assignment sequence until allocation.\u003c/p\u003e\u003cp\u003e\u003cb\u003eParticipants Eligibility Criteria\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eEthical approval\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e was obtained from the University of Benin Teaching Hospital, Benin City Edo State Nigeria with approval number 148260. This trial was also registered at Pactr.org with identifier number PACTR202201662414178. Participants were recruited from new adult patients attending the orthodontic Clinic of the University of Benin Teaching Hospital.\u003c/p\u003e\u003cp\u003e\u003cb\u003eInclusion Criteria\u003c/b\u003e\u003c/p\u003e\u003cp\u003ePatients aged 18 years, patients who underwent bilateral extraction of the first premolars in either one or both arches, no previous history of fixed orthodontic treatment, no history of systemic disease, bone pathology, or active periodontal disease. Patients who do not use tobacco.\u003c/p\u003e\u003cp\u003e\u003cb\u003eExclusion Criteria\u003c/b\u003e\u003c/p\u003e\u003cp\u003ePatients on prolonged use of antibiotics, anti-inflammatory drugs, systemic corticosteroids, and calcium channel blockers, poor oral hygiene even after attempts at motivation, patients who had transalveolar extraction of their first premolars, and patients with evidence of active dental caries.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSample Size\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe formula for comparing means between two groups was used to estimate the sample size for the split-mouth design\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003e\u003cb\u003eBlinding\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThis was ensured only during data collection as blinding of participants and clinicians was not feasible.\u003c/p\u003e\u003cp\u003e\u003cb\u003eIntervention\u003c/b\u003e\u003c/p\u003e\u003cp\u003eBefore the commencement of this procedure, informed consent was obtained from all study participants.\u003c/p\u003e\u003cp\u003eAccessibility of the area of interest for MOPs was performed as prescribed by Sangsuwon et al.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003ePatients who met inclusion criteria with the following diagnosis:\u003c/p\u003e\u003col style=\"list-style-type: lower-alpha;\"\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eClass I malocclusion cases with moderate to severe crowding\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eClass II malocclusion\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eClass III malocclusion\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eBimaxillary prognathism\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003cp\u003eAnd required 2-unit extractions in one or both arches as part of their treatment were recruited.\u003c/p\u003e\u003cp\u003eExtractions were carried out 2 weeks before commencing of fixed orthodontic treatment\u003c/p\u003e\u003cp\u003e0.022x0.030 Roth prescription; Dentaurum® brackets were used for all study participants. All teeth were leveled and aligned using various sizes of Nitinol wires. The canine retraction was done on a wire sequence of 0.019x0.025 stainless steel wire placed 4 weeks before commencing canine retraction.\u003c/p\u003e\u003cp\u003eA digital periapical radiograph was used to evaluate the bone between the canine and second premolar and to evaluate the root of the canine.\u003c/p\u003e\u003cp\u003eAnchorage for canine retraction was done using a 1.8x8mm miniscrew by GDT® inserted buccally between the roots of the first permanent molar and the second premolar bilaterally one week prior to the commencement of canine retraction.\u003c/p\u003e\u003cp\u003eImpression of the arch(s) to be used for MOP and control was made using Elvydent® colour changing, normal set, peppermint flavoured, and dust-free alginate material. Casts were produced using type IV Dental stone and then converted to digital models using a three-dimensional (3D) scanner. This was performed using the White Light Scanner (COMET5, 100-200-400, Steinbichler Optotechnik Germany) with 3D reverse modeling software.\u003c/p\u003e\u003cp\u003eThe distance between the centre of the canine and second premolar brackets was measured as used in a previous study.\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e These landmarks were chosen due to ease of identification. Values obtained are marked as T\u003csub\u003e0\u003c/sub\u003e. This is the baseline distance before the commencement of canine retraction. All measurements in this study were done on digital models obtained from casts using the 3D reverse scanner with modeling software to remove errors due to parallax. The accuracy of the scanner software was verified and confirmed by scanning and measuring 20 randomly selected casts which were rescanned and remeasured one week later\u003c/p\u003e\u003cp\u003eFollowing the method described by Sangsuwon et al.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e and Sharma et.al\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e MOP was performed at T\u003csub\u003e0\u003c/sub\u003e using orthodontic miniscrews as follows.\u003c/p\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003ePatient was asked to rinse with 15 ml of chlorhexidine for 30 seconds\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eThe area intended for MOPs following balloting was identified and anaesthetized first with a topical anaesthetic agent and then two minutes later infiltrated using a local anaesthetic agent (0.5ml Zey∞® lidocaine) placed 3mm distally away from the intended MOP site. The tip of a dental explorer was used to prick the attached gingiva around the area anaesthetized to establish that the anaesthesia was sufficient.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eA sterile GDT® orthodontic miniscrew with a dimension of 6mm x1.5mm attached to a driver was used to make 3 equally spaced vertical perforations of about 2mm apart with the first about apical to the Attached gingiva on the buccal cortical plate on a straight line drawn 3mm parallel to the distal surface of the canine to be retracted by gentle rotational movement of the miniscrew driver with screw attached until the desired depth 6mm was reached. One miniscrew per patient per visit was used to reduce the chances of infection from the procedure.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eWhere bleeding was observed after MOP, gentle pressure using a gauze pack was used to arrest the bleeding.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eNo analgesics were offered after the procedure and all through the duration of the study. Three of the study participants reported severe pain within 24 hours of MOP and were allowed to take 1g of paracetamol.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003cp\u003eA 9mm NiTi closed coil spring (Sentalloy, 3M Unitek, USA) was used in canine retraction in both the experiment and control side anchored to the head of the miniscrew posteriorly and to the canine hooks on the canine bracket anteriorly.\u003c/p\u003e\u003cp\u003eA force of 150g\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e which was produced by 6mm stretching of the springs and was calibrated using Correx guage®. where canine–miniscrew distance was more than the activated coil spring length, ligature wire was used to account for the length disparity by attaching it to the coil spring and secured to the miniscrew to ensure uniform force delivery on coil springs on the right and left quadrant on the same arch.\u003c/p\u003e\u003cp\u003eA repeat impression of the arch(s) with MOP was made at weeks 8 and 12 for all patients and casts were converted to digital models.\u003c/p\u003e\u003cp\u003eThe new distance between the centre of canine and second premolar brackets was measured in T\u003csub\u003eweek8\u003c/sub\u003e and T\u003csub\u003eweek12\u003c/sub\u003e. The difference in this new distance T\u003csub\u003eweek8\u003c/sub\u003e from the baseline (T\u003csub\u003eO\u003c/sub\u003e) and T\u003csub\u003eweek12 from\u003c/sub\u003e T\u003csub\u003e0\u003c/sub\u003e is the canine retraction rate in 8 weeks and 12 weeks and marked as T\u003csub\u003e1\u003c/sub\u003e and T\u003csub\u003e2\u003c/sub\u003e respectively. Repeat MOPs were done only for EG\u003csub\u003e2\u003c/sub\u003e patients at 8 weeks from the commencement of retraction to evaluate the effect of repeat MOP application. This is to attempt to sustain the maximum effect of RAP which is believed to start to wane after 2 months. \u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe secondary outcome of this study which was pain and discomfort was measured using the Wong-Baker FACES Pain Rating Scale on 24-hour, 3- and 7-days post-MOP procedures at T\u003csub\u003e0\u003c/sub\u003e for all participants. Study participants were advised not to take any form of pain medication during the study and to notify the investigator when they had severe pain. Reminders were sent electronically, and values were sent electronically on the day.\u003c/p\u003e\u003cp\u003eAll values obtained were entered into the data collection form for analysis. Canine retraction in this study was the total distance moved by the canine in 12 weeks.\u003c/p\u003e\u003cp\u003e\u003cb\u003eEthical Consideration\u003c/b\u003e\u003c/p\u003e\u003cp\u003e Before the commencement of this study, approval was obtained from the Health Research Ethics Committee of the University of Benin Teaching Hospital, Benin City with approval number ADM/E22/A/VOL.VII/148260.\u003c/p\u003e\u003cp\u003eAlso, an informed consent form was administered to every patient who met the inclusion criteria after a thorough explanation of the procedure and its possible advantages and complications for signature in the presence of a witness.\u003c/p\u003e\u003ch2\u003eData analysis\u003c/h2\u003e\u003cp\u003eData collected was analyzed using SPSS version 23.0 (SPSS Inc., Chicago, Ill). The variables and outcome of the study were described by descriptive statistics using mean, standard deviation (SD), range (minimum-maximum), charts, and tables. Shapiro-Wilk test of normality was used to determine the appropriate parametric and non-parametric tests. Paired samples were used to compare the change in canine retraction over time within CG and EG while independent samples were used to compare the canine retraction rate between CG and EG. A comparison of the canine retraction rate between genders was done using an independent sample. This was also done to compare the maxilla and mandible. The relationship between age and the canine retraction rate was determined using Pearson’s correlation.\u003c/p\u003e\u003cp\u003eThe pain levels were described using the median and interquartile range; a comparison between the MOP and control group was done using the Mann-Whitney U statistics.\u003c/p\u003e\u003cp\u003eAll analysis was evaluated with a P ≤ 0.05, considered significant in all cases, at 95% confidence intervals (CI).\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003e\u003cb\u003eParticipant flow\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe subjects\u0026rsquo; ages ranged from 18\u0026ndash;33 years (Fig.\u0026nbsp;1) with a mean age of 24.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6 years and consisted of 11 (64.7%) females and 6 males (35.3%). 29 jaws (14 upper and 15 lower) consisting of 58 quadrants were used in this study. In this study, 18 subjects were recruited into the study. 1 was lost due to loss of anchorage. Out of the 17 subjects who completed the study, 12 had 4-unit extractions constituting 48 quadrants and 5 had 2-unit extractions constituting 10 quadrants. 14 quadrants received one-off MOP with 14 contralateral quadrants as control and 15 quadrants received MOP twice with 15 contralateral quadrants as control.\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable I: Sociodemographic Characteristics of the Participants\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParameter\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eN (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMean Age (in years)\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6 (35.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e21.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11 (64.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e26.3\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17 (100.0%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e24.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003eSD\u0026thinsp;=\u0026thinsp;Standard deviation\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eAverage Distance Between Mid-Canine Bracket and Mid-2nd Premolar Bracket\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable II: Average distance between mid-canine bracket and mid-2nd premolar bracket\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabb\" border=\"1\"\u003e\u003ccolgroup cols=\"8\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMOP (T\u003csub\u003e0\u003c/sub\u003e mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eControl (T\u003csub\u003e0\u003c/sub\u003e mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMOP (T\u003csub\u003eweek8\u003c/sub\u003e mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eControl (T\u003csub\u003eweek8\u003c/sub\u003e mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMOP (T\u003csub\u003eweek12\u003c/sub\u003e mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eControl (T\u003csub\u003eweek12\u003c/sub\u003e mm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eMean\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e15.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e13.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e9.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e11.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eStd. Deviation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eAt T\u003csub\u003e0\u003c/sub\u003e, the average distance between the mid-canine bracket and mid-second premolar bracket was 15.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2.5mm in the MOP group and 15.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9mm in the control group. At T\u003csub\u003eweek8\u003c/sub\u003e, the average distance was 12.0\u0026thinsp;\u0026plusmn;\u0026thinsp;2.7mm and 13.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2mm in the MOP and control group respectively. While at T\u003csub\u003eweek12\u003c/sub\u003e, the average distance was 9.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2mm in the MOP group and 11.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3mm in the control group.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe average canine retraction rate increased over time. At both points in time, the average canine retraction was higher in the MOP group (Figure IV).\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eCanine Retraction Rate (Mean Difference) within Experiment and Control Groups at 8 Weeks and 12 Weeks\u003c/b\u003e\u003c/p\u003e\u003cp\u003eIn the MOP group (Table III), the mean canine retraction rate (CRR) was 3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8mm at week 8, 6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8mm at week 12 while in the control group, the mean CRR was 2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5mm at week 8, and 4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6mm at week 12. The retraction rate (Table\u0026nbsp;3) at week 8 and week 12 differed significantly from baseline (week 0) in both the MOP (p\u0026thinsp;=\u0026thinsp;0.000) and control group (p\u0026thinsp;=\u0026thinsp;0.000).\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable III: Canine retraction rate (mean difference) within experiment and control groups at 8 weeks and 12 weeks\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabc\" border=\"1\"\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u003cp\u003eMean Difference (mm)\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eT\u003c/b\u003e\u003csub\u003e\u003cb\u003e1\u003c/b\u003e\u003c/sub\u003e \u003cb\u003e(T0 \u0026ndash; T\u003c/b\u003e\u003csub\u003e\u003cb\u003eweek8\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003cb\u003e-value\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eT\u003c/b\u003e\u003csub\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sub\u003e \u003cb\u003e(T0 \u0026ndash; T\u003c/b\u003e\u003csub\u003e\u003cb\u003eweek12\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003cb\u003e-value\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMOP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.000**\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.000**\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.000**\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.000**\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e\u003cp\u003eT1\u0026thinsp;=\u0026thinsp;week 8, T2\u0026thinsp;=\u0026thinsp;week 12, SD\u0026thinsp;=\u0026thinsp;standard deviation\u003c/p\u003e\u003cp\u003e** Significance at the 0.01 level\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eComparison between the Canine Retraction Rate (CRR) of MOP and the Control Group\u003c/b\u003e\u003c/p\u003e\u003cp\u003eAs shown in Table IV, at week 8 the mean CRR of the MOP group was significantly higher (p\u0026thinsp;=\u0026thinsp;0.011) than that of the control group by a difference of \u0026asymp;\u0026thinsp;1.1mm (0.3\u0026ndash;2.0, 95% CI, p\u0026thinsp;=\u0026thinsp;0.011). This trend was also observed at week 12; the mean CRR of the MOP group was statistically significantly higher (p\u0026thinsp;=\u0026thinsp;0.001) than that of the control group by a difference of \u0026asymp;\u0026thinsp;1.5mm (0.6\u0026ndash;2.4, 95% CI, p\u0026thinsp;=\u0026thinsp;0.001).\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable IV: Comparison between the Canine Retraction Rate of MOP and Control Group\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabd\" border=\"1\"\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePeriod\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMOP\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eMean (mm)\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eMean (mm)\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eMean Difference (mm)\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e95% CI\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003ep-\u003c/b\u003e\u003cb\u003evalue\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.3\u0026ndash;2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.011*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.6\u0026ndash;2.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e\u003cp\u003eT1\u0026thinsp;=\u0026thinsp;CRR at week 8, T2\u0026thinsp;=\u0026thinsp;CRR at week 12, SD\u0026thinsp;=\u0026thinsp;Standard Deviation, CI\u0026thinsp;=\u0026thinsp;Confidence Interval\u003c/p\u003e\u003cp\u003e* Significance at the 0.05 level\u003c/p\u003e\u003cp\u003e** Significance at the 0.01 level\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eCanine Retraction Rate Based on the Number of MOP Appointments\u003c/b\u003e\u003c/p\u003e\u003cp\u003eAt weeks 8 and 12, as shown in Table V, the average CRR was slightly higher in participants who had twice MOP applications when compared to those who had one-off MOP application although the difference was not statistically significant at the various time intervals (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05 in both cases).\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable V: Canine retraction rate of the MOP group based on the number of MOP appointments\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabe\" border=\"1\"\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePeriod\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNA\u0026thinsp;=\u0026thinsp;1\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNA\u0026thinsp;=\u0026thinsp;2\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eMean (mm)\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eMean (mm)\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eMean Difference (mm)\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e95% CI\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003ep-\u003c/b\u003e\u003cb\u003evalue\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.0\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-2.1\u0026ndash;2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.011*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.6\u0026ndash;2.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e\u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;week 8, T\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;week 12, SD\u0026thinsp;=\u0026thinsp;standard deviation, CI\u0026thinsp;=\u0026thinsp;confidence interval\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eGender and Canine Retraction Rate (CRR) in Experiment and Control Groups\u003c/b\u003e\u003c/p\u003e\u003cp\u003eIn the MOP group, the mean CRR was higher in males across the time periods although the difference was only statistically significant at week 12 (p\u0026thinsp;=\u0026thinsp;0.020). In the control group, the mean CRRs of males were slightly higher than that of females but not significant at week 8 (p\u0026thinsp;=\u0026thinsp;0.353) as well as at week 12 (p\u0026thinsp;=\u0026thinsp;0.357).\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable VI: Canine retraction rate based on gender\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabf\" border=\"1\"\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTime\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMale Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eFemale Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMD (mm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003ep-\u003c/em\u003evalue\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eMOP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eT\u003c/b\u003e\u003csub\u003e\u003cb\u003e1\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.4\u0026thinsp;\u0026plusmn;\u0026thinsp;2.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-0.9\u0026ndash;2.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.390\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eT\u003c/b\u003e\u003csub\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.3\u0026ndash;2.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.020\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eT\u003c/b\u003e\u003csub\u003e\u003cb\u003e1\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-0.6 -1.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.353\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eT\u003c/b\u003e\u003csub\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-0.7\u0026ndash;1.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.357\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e\u003cp\u003eT\u003csub\u003e1\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;week 8, T\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;week 12, SD\u0026thinsp;=\u0026thinsp;standard deviation, MD\u0026thinsp;=\u0026thinsp;mean difference\u003c/p\u003e\u003cp\u003e* Significance at the 0.05 level\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eAge and Canine Retraction Rate\u003c/b\u003e\u003c/p\u003e\u003cp\u003eFigure V below shows the correlation between the age of the subjects and the canine retraction rate in both the MOP and control group. At week 8 (T\u003csub\u003e1\u003c/sub\u003e), there was no relationship between age and canine retraction rate in both groups. However, at week 12 (T\u003csub\u003e2\u003c/sub\u003e), in the MOP group there was a significant negative relationship (r = -0.49, p = 0.007) between age and canine retraction (retraction decreased as age increased).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003e\u003cb\u003eAssessment and Comparison of the Level of Pain between the Experiment and Control Groups\u003c/b\u003e\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe level of pain recorded in the groups is shown in the plot below (Fig. VI). In the MOP group, the median pain level was 6.0 (4.0\u0026ndash;8.0) on day 1, 4.0 (2.0\u0026ndash;5.0) on day 3 and 1.0 (0.0 \u0026minus;\u0026thinsp;2.0) on day 7. In the control group, the median pain level was 5.0 (4.0\u0026ndash;6.0) on day 1, 3.0 (1.0\u0026ndash; 4.0) on day 3, and 0.0 (0.0\u0026ndash;1.0) on day 7. In both groups, there was a significant reduction in the level of pain as the days increased (p\u0026thinsp;=\u0026thinsp;0.000, in both groups).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eComparison between the Pain Level of MOP and the Control Group\u003c/b\u003e\u003c/p\u003e\u003cp\u003eBetween the experiment (MOP) and control groups, as shown in Table VII, the distribution of pain levels was not the same but the difference was not statistically significant at 24 hours post-procedure (p\u0026thinsp;=\u0026thinsp;0.094) while at day 3 and day 7, the pain levels differences of the MOP group was statistically significant than that of the control (p\u0026thinsp;=\u0026thinsp;0.027 and p\u0026thinsp;=\u0026thinsp;0.042 respectively). In the MOP group, there was no significant difference in the distribution of pain from the control group at day 1 (24 hours) (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) but there was a significant difference in the distribution of pain at day 3 (p\u0026thinsp;=\u0026thinsp;0.030) and day 7 (p\u0026thinsp;=\u0026thinsp;0.040).\u003c/p\u003e\u003cp\u003e\u003cem\u003eTable VII: Comparison between the pain level of MOP and control group\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabg\" border=\"1\"\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMOP (N\u0026thinsp;=\u0026thinsp;29)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eControl (N\u0026thinsp;=\u0026thinsp;29)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eMedian (IQR)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eMedian (IQR)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003ep-\u003c/b\u003e\u003cb\u003evalue\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDay 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.0 (4.0\u0026ndash;8.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.0 (4.0\u0026ndash;6.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.094\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDay 3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.0 (2.0\u0026ndash;5.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.0 (1.0\u0026ndash;4.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.027*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDay 7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.0 (0.0\u0026ndash;2.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.0 (0.0\u0026ndash;1.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.042*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e\u003cp\u003eIQR\u0026thinsp;=\u0026thinsp;Inter-quartile range\u003c/p\u003e\u003cp\u003e* Significance at the 0.05 level\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThe daunting task of reducing the treatment duration\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e as well as its accompanying undesirable side effects associated with prolonged treatment time in fixed orthodontic treatment in general and among adult patients in particular, has led to the introduction of new treatment modalities such as MOP.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThis split-mouth study design helped reduce the biological variability as each subject served as its control. Homogenous subjects (young adult patients) were as much as possible used in this study. This allowed for similar inflammatory responses to MOP based on their close age range. Cofounders were eliminated using the inclusion criteria.\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e This study conducted to determine CRR using a NiTi close coil spring with MOP on the experiment side and NiTi close coil spring only on the control side produced a mean retraction rate of 6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8mm from the experiment sides and 4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6mm from the control sides at the end of 12weeks of retraction. This finding was significantly higher on the experiment side which had a NiTi close coil spring with MOPs applied when compared with that on the control side which had a NiTi close coil spring only. This result has been attributed to the RAP elicited by the micro-traumatic nature of MOP which translates into an increase in inflammatory markers and osteoclastic activity which is the hallmark of OTM.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e The finding from this study which showed about 1.34 times faster CRR is in keeping with reports from other studies like that by Zoya Ahsan et.al\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e which had 30 participants and reported a 1.6 times faster retraction rate. Other studies have reported even higher values of a 2.3 times faster retraction rate\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. Studies that have shown no difference in CRR following MOP application also exist in the literature with Alkebsi et.al reporting no difference whatsoever in retraction rate.\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e,\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eOne of the popularized distinctive advantages of MOP placement is the repeatability of the procedure as opposed to the other highly invasive surgical-assisted techniques. This repeat application is believed to cause a constant circulation of inflammatory chemokines and cytokines within the localized region where MOP is applied thus leading to sustained increase in localized alveolar bone turnover.\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e,\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e Wilcko et.al reported that RAP takes effect in 1 or 2 days following the surgical intervention and reaches its peak levels in about one 1 or 2 months and then starts to wane,\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e repeats of MOP in a subset of the experimental sides in this study were planned for 8 weeks from the time of commencing this study. There was no significant increase in CRR when MOP was repeated 8 weeks after study commencement in the subset within the experiment group. This finding agrees with that reported in another study where there was no increase in OTM with 4 weekly applications of MOP in the course for 3 months.\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e,\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e Our finding may have been due to a decrease in the force in the NiTi close coil spring as the distance between the canine and the second premolar decreases as the coil activation was done just once at the beginning of the study. However, a study from Attri et.al reported a significant increase in retraction rate and faster space closure when MOPs were repeatedly applied every 28 days over 3 months.\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e Attri et.al had six MOPs repeatedly applied to both the mesial and distal aspects of the alveolar bone of the canines to the retracted. This may have produced more RAP effect leading to an increase in OTM.\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eTherefore, there may be a need to evaluate force reactivation with repeat MOP application, the number and points of application of the repeated MOPs, and where possible depth of MOP applied to be able to sufficiently state whether repeat MOP are effective or ineffective. Although studies have reported no increase in OTM following MOP whether at the beginning of the study or with repeated application the authors postulate that the RAP elicited by MOP is so small that that the biological response is minimal.\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe average rate of tooth movement by conventional orthodontics is estimated to be around 0.8 to 1.2 mm/month when continuous forces are being applied.\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e was observed to be less than that derived from this study in both the control and experiment sides with values of 1-2.6mm/month. This observation may have been a result of the differences in the form of anchorage used. This study used absolute anchorage in the form of TADs. This is also true when compared to other studies on canine retraction rates published by Dixon et al\u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e who observed that the rate of canine retraction with NiTi closed coil springs was 0.81 mm/month and Cacciafesta et al\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e who reported a 1.1 mm/month canine movement but did not use absolute anchorage. Therefore, absolute anchorage should be considered where possible if a faster OTM is desired. This eliminates anchorage loss and invariably reduces OTM associated with other forms of anchorage design.\u003c/p\u003e\u003cp\u003eOn the secondary outcome of our study which was pain and discomfort, the highest values of pain scores were recorded on day one in both the control and experimental side. This can easily be attributed to the force effect on the periodontium of the canines by the NiTi close coil spring. The pain perception of the study participants from the experiment quadrants when compared to that from the control quadrants was statistically not significant 24 hours post MOP application but was statistically significant at day 3 and day 7 post MOP application. Even though there was a decrease in pain reported from both the experiment and control sides as the number of days post-MOP increased, the pain levels on the experiment sides were higher at day 3 and day 7. This can be a result of the microtrauma associated with MOP both to the mucosa and the underlying alveolar bone and or lack of blinding in the application of MOP to the experiment quadrants in this study. Our study had 11 females and 6 males with three of the female study participants reporting severe pain before 24 hours post-MOP application with all three requiring a single dose of Paracetamol 1g for their pain. Some other studies have not only shown more pain experience on the experiment quadrants but have also reported adverse effects on patients\u0026rsquo; quality of life.\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eOther complications associated with MOP administration which even though not reported in the results were observed was rotation/ tipping of the canines. This was observed in both the experiment and control mouth sides despite the use of 0.19 x 0.025 stainless steel wire placed 4 weeks before commencement of retraction and throughout retraction. The direction of force application could have accounted for this finding. Canine root resorption which is also an associated MOP complication was equally assessed by comparing digital periapical radiographs taken at zero week and 12th week of this study with no form of resorption observed after 12 weeks.\u003c/p\u003e\u003cp\u003eA reduction in time of about 2.9 weeks was observed from this study in the canine retraction phase of fixed orthodontic treatment. This may not still be significant as the overall reduction in orthodontic treatment time. Therefore, MOP applicability in other stages of orthodontic treatment must be equally evaluated if an appreciable reduction in total treatment time is desired which will improve its acceptance by both patients and clinicians.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eFrom this study, the canine retraction rate using a NiTi close coil spring with adjunctive miniscrew facilitated MOP was significantly higher than that from the use of a NiTi close coil spring alone.\u003c/p\u003e\u003cp\u003eAlso, the canine retraction rate using NiTi close coil spring with twice application of adjunctive miniscrew facilitated MOP at the commencement of retraction and 8 weeks afterward did not produce a significantly faster retraction rate when compared to once the application of MOP at the commencement of canine retraction.\u003c/p\u003e\u003cp\u003ePain from the administration of adjunctive MOP to NiTi close coil spring activation in canine retraction even though was not statistically significant 24 hours post-administration from pain from NiTi close coil activation alone, pain from the former was significantly higher than pain from the later by day 3 and day 7 post-MOP administration.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eCONFLICTS OF INTEREST\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors declare no conflicts of interest related to this study. The research was conducted independently, without financial or personal relationships that could inappropriately influence or bias our findings. All materials and equipment used in this study were obtained through standard procurement channels, and no external funding or sponsorship was received.\u003c/p\u003e\n\u003cp\u003eAUTHORS\u003c/p\u003e\n\u003cp\u003eHilary Smith Ojebor\u003csup\u003e1\u003c/sup\u003e, Monica Ndudi Adekoya\u003csup\u003e1\u003c/sup\u003e, Alice Aiewreye Umweni\u003csup\u003e2, 3\u003c/sup\u003e, Clement Chinedu Azodo\u003csup\u003e4,5\u003c/sup\u003e, Godwin Obi Bassey\u003csup\u003e5\u003c/sup\u003e, \u0026nbsp;Nonso Emmanuel Onyia\u003csup\u003e6\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u003c/sup\u003eUniversity of Calabar, Calabar, Nigeria, Department of Child Dental Health\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e2\u003c/sup\u003eUniversity of Benin Teaching Hospital, Benin City, Nigeria, Department of Orthodontics\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e3\u003c/sup\u003eUniversity of Benin, Benin City, Nigeria, Department of Orthodontics\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e4\u003c/sup\u003eUniversity of Benin, Benin City, Nigeria, Department of Periodontics\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003csup\u003e5\u003c/sup\u003e\u003c/strong\u003eUniversity of Benin Teaching Hospital, Benin City, Nigeria, Department of Periodontics\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e6\u003c/sup\u003eUniversity of Calabar, Calabar, Nigeria, Department of Oral Medicine/Oral Pathology\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorresponding Author Details\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eName\u003c/strong\u003e: Godwin Obi Bassey\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEmail\u003c/strong\u003e: [email protected]\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFUNDING\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo external funding was provided for this study. All funding was provided by the authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTRIAL REGISTRATION DETAILS\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRegistry 1: University of Benin Teaching Hospital, Benin City Edo State, Nigeria\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Registration number: 148260\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Registration date: 9 Jan 2020\u003c/p\u003e\n\u003cp\u003eRegistry 2: Pactr.org\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Registration number: PACTR202201662414178\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Registration date: 24 Jan 2022\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCONSENT TO PUBLISH DECLARATION\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable as study does not contain any identifying information of study participants.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eH.S. was the primary researcher and carried out data collection, and in combination with G.O., wrote and edited the main manuscript text. M.N., A.A., and C.C. were the supervisors and participated in the study conception/design and data interpretation process. N.E. assisted in data collection and analysis. All Authors reviewed the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eNimeri G, Kau CH, Abou-Kheir NS, Corona R. Acceleration of tooth movement during orthodontic treatment-a frontier in orthodontics. \u003cem\u003eProg Orthod\u003c/em\u003e. 2013; 14:1-8.\u003c/li\u003e\n\u003cli\u003eMavreas D, Athanasiou AE. Factors affecting the duration of orthodontic treatment: a systematic review. \u003cem\u003eThe European Journal of Orthodontics\u003c/em\u003e. 2008;30(4):386-395.\u003c/li\u003e\n\u003cli\u003ePilon JJGM, Kuijpers-Jagtman AM, Maltha JC. Magnitude of orthodontic forces and rate of bodily tooth movement. An experimental study. \u003cem\u003eAmerican Journal of Orthodontics and Dentofacial Orthopedics\u003c/em\u003e. 1996;110(1):16-23.\u003c/li\u003e\n\u003cli\u003eSkidmore KJ, Brook KJ, Thomson WM, Harding WJ. Factors influencing treatment time in orthodontic patients. \u003cem\u003eAmerican Journal of Orthodontics and Dentofacial Orthopedics\u003c/em\u003e. 2006;129(2):230-238.\u003c/li\u003e\n\u003cli\u003eApajalahti S, Peltola JS. Apical root resorption after orthodontic treatment\u0026mdash;a retrospective study. \u003cem\u003eThe European Journal of Orthodontics\u003c/em\u003e. 2007;29(4):408-12.\u003c/li\u003e\n\u003cli\u003eDiamanti‐Kipioti A, Gusberti FA, Lang NP. Clinical and microbiological effects of fixed orthodontic appliances. \u003cem\u003eJ Clin Periodontol\u003c/em\u003e. 1987;14(6):326-33.\u003c/li\u003e\n\u003cli\u003ePandis N. Sample calculation for split-mouth designs. \u003cem\u003eAmerican journal of orthodontics and dentofacial orthopedics\u003c/em\u003e. 2012;141(6):818-9.\u003c/li\u003e\n\u003cli\u003eSangsuwon C, Alansari S, Nervina J, Teixeira CC, Alikhani M. Micro-osteoperforations in accelerated orthodontics. \u003cem\u003eClinical Dentistry Reviewed\u003c/em\u003e. 2018; 2:1-10.\u003c/li\u003e\n\u003cli\u003eFeizbakhsh M, Zandian D, Heidarpour M, Farhad SZ, Fallahi HR. The use of micro-osteoperforation concept for accelerating differential tooth movement. \u003cem\u003eJ World Fed Orthod\u003c/em\u003e. 2018;7(2):56-60.\u003c/li\u003e\n\u003cli\u003eSharma K, Batra P, Sonar S, Srivastava A, Raghavan S. Periodontically accelerated orthodontic tooth movement: a narrative review. \u003cem\u003eJ Indian Soc Periodontol\u003c/em\u003e. 2019;23(1):5-11.\u003c/li\u003e\n\u003cli\u003eSukurica Y, Karaman A, G\u0026uuml;rel HG, Dolanmaz D. Rapid canine distalization through segmental alveolar distraction osteogenesis. \u003cem\u003eAngle Orthod\u003c/em\u003e. 2007;77(2):226-36.\u003c/li\u003e\n\u003cli\u003eWilcko MT, Wilcko WM, Pulver JJ, Bissada NF, Bouquot JE. Accelerated osteogenic orthodontics technique: a 1-stage surgically facilitated rapid orthodontic technique with alveolar augmentation. \u003cem\u003eJournal of oral and maxillofacial surgery\u003c/em\u003e. 2009;67(10):2149-59.\u003c/li\u003e\n\u003cli\u003eSafir NK, Athar S, Prashantha GS. Acceleratory orthodontics-the race against time. \u003cem\u003eJournal of Dental and Orofacial Research\u003c/em\u003e. 2018;14(2):80-7.\u003c/li\u003e\n\u003cli\u003eNicozisis JL. Accelerated orthodontics through micro-osteoperforation. \u003cem\u003eOrthodontic Practice US\u003c/em\u003e. 2013;4(3):56-7.\u003c/li\u003e\n\u003cli\u003eGiannopoulou C, Dudic A, Pandis N, Kiliaridis S. Slow and fast orthodontic tooth movement: an experimental study on humans. \u003cem\u003eEur J Orthod\u003c/em\u003e. 2016;38(4):404-8.\u003c/li\u003e\n\u003cli\u003eAl-Khalifa KS, Baeshen HA. Micro-osteoperforations and its effect on the rate of tooth movement: a systematic review. \u003cem\u003eEur J Dent\u003c/em\u003e. 2021;15(01):158-167.\u003c/li\u003e\n\u003cli\u003eAhsan Z, Khan M, Jan A, Shah TI, Naeem S. The use of micro-osteoperforation concept for accelerating differential tooth movement. \u003cem\u003ePakistan Armed Forces Medical Journal\u003c/em\u003e. 2021;71(3):844-8.\u003c/li\u003e\n\u003cli\u003eAlkebsi A, Al-Maaitah E, Al-Shorman H, Alhaija EA. Three-dimensional assessment of the effect of micro-osteoperforations on the rate of tooth movement during canine retraction in adults with Class II malocclusion: a randomized controlled clinical trial. \u003cem\u003eAmerican Journal of Orthodontics and Dentofacial Orthopedics\u003c/em\u003e. 2018;153(6):771-85.\u003c/li\u003e\n\u003cli\u003eAboalnaga AA, Salah Fayed MM, El-Ashmawi NA, Soliman SA. Effect of micro-osteoperforation on the rate of canine retraction: a split-mouth randomized controlled trial. \u003cem\u003eProg Orthod\u003c/em\u003e. 2019; 20:1-9.\u003c/li\u003e\n\u003cli\u003eAttri S, Mittal R, Batra P, et al. Comparison of rate of tooth movement and pain perception during accelerated tooth movement associated with conventional fixed appliances with micro-osteoperforations\u0026ndash;a randomised controlled trial. \u003cem\u003eJ Orthod\u003c/em\u003e. 2018;45(4):225-33.\u003c/li\u003e\n\u003cli\u003eAbdelhameed AN, Refai WMM. Evaluation of the effect of combined low energy laser application and micro-osteoperforations versus the effect of application of each technique separately on the rate of orthodontic tooth movement. \u003cem\u003eOpen Access Maced J Med Sci\u003c/em\u003e. 2018;6(11):2180.\u003c/li\u003e\n\u003cli\u003eFattori L, Sendyk M, de Paiva JB, Normando D, Neto JR. Micro-osteoperforation effectiveness on tooth movement rate and impact on oral health related quality of life: a randomized clinical trial. \u003cem\u003eAngle Orthod\u003c/em\u003e. 2020;90(5):640-7.\u003c/li\u003e\n\u003cli\u003eCramer CL, Campbell PM, Opperman LA, Tadlock LP, Buschang PH. Effects of micro-osteoperforations on tooth movement and bone in the beagle maxilla. \u003cem\u003eAmerican Journal of Orthodontics and Dentofacial Orthopedics\u003c/em\u003e. 2019;155(5):681-92.\u003c/li\u003e\n\u003cli\u003eSugimori T, Yamaguchi M, Shimizu M, et al. Micro-osteoperforations accelerate orthodontic tooth movement by stimulating periodontal ligament cell cycles. \u003cem\u003eAmerican Journal of Orthodontics and Dentofacial Orthopedics\u003c/em\u003e. 2018;154(6):788-96.\u003c/li\u003e\n\u003cli\u003eDixon V, Read MJF, O\u0026rsquo;brien KD, Worthington H V, Mandall NA. A randomized clinical trial to compare three methods of orthodontic space closure. \u003cem\u003eJ Orthod\u003c/em\u003e. 2002;29(1):31-6.\u003c/li\u003e\n\u003cli\u003eCacciafesta V, Sfondrini MF, Ricciardi A, Scribante A, Klersy C, Auricchio F. Evaluation of friction of stainless steel and esthetic self-ligating brackets in various bracket-archwire combinations. \u003cem\u003eAmerican Journal of Orthodontics and Dentofacial Orthopedics\u003c/em\u003e. 2003;124(4):395-402.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Canine Retraction Rate, Miniscrew-facilitated Micro-osteoperforation, Split-mouth Study, Short-term Pain Levels, Canine Retraction Dimensions, Orthodontic Tooth Movement, Buccal Cortical Plate Perforations, Accelerated Orthodontics","lastPublishedDoi":"10.21203/rs.3.rs-6992572/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6992572/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction:\u003c/h2\u003e\u003cp\u003eCanine Retraction Rate (CRR) using NiTi closed coil springs may be enhanced by miniscrew-facilitated osteoperforation (MOP).\u003c/p\u003e\u003ch2\u003eAims and Objectives:\u003c/h2\u003e\u003cp\u003eTo determine whether MOP significantly accelerates CRR in adults undergoing bilateral first premolar extraction and to evaluate short-term pain levels post-procedure.\u003c/p\u003e\u003ch2\u003eStudy Design:\u003c/h2\u003e\u003cp\u003eA split-mouth randomized controlled trial with 17 participants (Mean age: 24.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6 years; 64.7% females). Randomization was performed per arch with concealed allocation.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eOn the experimental side, three vertical perforations were created on the buccal cortical plate using a 6 mm \u0026times; 1.5 mm miniscrew. A 9 mm NiTi closed coil spring delivering 150 g of force facilitated canine retraction. CRR was measured at weeks 1, 8, and 12, and pain levels were assessed at 24 hours, 3-, and 7-days post-MOP using the Wong-Baker FACES Pain Scale.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eThe MOP group showed higher mean CRRs (3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8 mm at week 8, 6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8 mm at week 12) compared to the control group (2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5 mm at week 8, 4.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6 mm at week 12). Pain levels at days 3 and 7 post-MOP were significantly higher in the MOP group (p\u0026thinsp;=\u0026thinsp;0.027 and p\u0026thinsp;=\u0026thinsp;0.042).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eMOP significantly accelerates canine retraction but increases short-term pain levels.\u003c/p\u003e","manuscriptTitle":"Evaluation of Canine Retraction Rate in Adult Orthodontic Patients Using Miniscrew-Facilitated Micro-Osteoperforation: A Split-Mouth Randomized Clinical Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-18 13:21:57","doi":"10.21203/rs.3.rs-6992572/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"15dd2e39-5956-4c0d-8d3f-dc13981465c7","owner":[],"postedDate":"July 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-07-22T09:53:51+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-18 13:21:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6992572","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6992572","identity":"rs-6992572","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}