Dental implant site preparation with conventional rotary drill or piezosurgery: five-year after placement results from a within person randomised controlled trial

Dental implant site preparation with conventional rotary drill or piezosurgery: five-year after placement results from a within person randomised controlled trial | 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 Dental implant site preparation with conventional rotary drill or piezosurgery: five-year after placement results from a within person randomised controlled trial Adriano Azaripour, Vittorio Farina, Marco Esposito, Jacopo Buti, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5278685/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Purpose: To evaluate whether there are clinical benefits by preparing dental implant sites using piezosurgery instead of conventional rotary drills in healed bone crests and if initial crestal soft tissue thickness could have an impact on marginal bone loss. Methods: Twenty-five partially edentulous patients requiring two single implants in molar/premolar areas had each site randomly allocated to either piezosurgery or to conventional rotary drill preparation according to a split-mouth design. Definitive screw-retained metal-ceramic crowns were delivered after 6 months. All patients were followed to 5 years after placement. Outcome measures were: implant/crown failures, complications, peri-implant marginal bone level changes, resonance frequency analysis (RFA), and time required come complete site preparation, recorded, when possible, by blinded assessors. Results: No patients dropped-out and no implant failed. Five years after placement, there were no statistically significant differences for complications (only one complication in the piezo group: difference = 0.04; P = 1), for peri-implant bone loss (difference = -0.11 mm; 95% CI -0.24 to 0.01; P = 0.083), and for RFA changes (6 months) (difference = -0.35; 95% CI -1.95 to 1.25; P = 0.672 between groups. Significantly more time was needed to prepare implant sites with piezosurgery (difference = 236.8 sec; 95% CI -286.12 to -187.48; P <0.0001). Initial soft tissue thickness had no effect on peri-implant bone loss (estimate = 0.05; 95% CI -0.03; 0.12; P = 0.239). Conclusions: No clinically appreciable differences were noticed when placing implants using piezosurgery or conventional instrumentation with rotary drill, however, the preparation with rotary drills was on average 4 minutes faster. No effect of initial crestal soft tissue thickness was observed on peri-implant bone loss. dental implants implant site preparation piezoelectric surgery rotary drills Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 INTRODUCTION Among the numerous ongoing debates in implant dentistry there is also the one about which could be the best way to prepare implants sites for placing dental implants. Traditionally, implant sites were prepared by a sequence of drills of increased diameters, the last diameter depending on the implant diameter, the quality of bone and the wished insertion torque. Despite that rotary drills are almost universally used for implant sites preparation, some authors suggested the use of piezosurgery instead, either alone ( 1 ) or in combination with rotary drills ( 2 ). The hypothesis behind is that piezosurgery may induce a more precise cut as well as inducing less heating, therefore decreasing the risk of bone necrosis and improving bone healing compared to rotary drills ( 3 ). At the same time, piezosurgery can be less aggressive than rotary drills if a nerve is accidentally hit. On the other hand, an animal study showed a tendency for more bone to implant contact and RFA, believed to corresponds to increased implant stability, at drilled sites when compared to implant sites prepared with piezosurgery ( 4 ). In addition, drilling required a 4-minute shorter preparation time and two implants did not integrated in the piezo group versus one in the drilled group ( 4 ). Another ex-vivo study failed to show any statistically significant differences between drilling and piezosurgery regarding heat generation and implant stability assessed with the resonance frequency analysis (RFA) ( 5 ). However, site preparation with piezosurgery took significantly longer time than with rotary drills. Therefore, it would be interesting to know whether a better clinical outcome could be obtained by using piezoelectric surgery instead of conventional drills to prepare dental implant sites. The aims of this RCT were primarily to evaluate clinical outcome of preparing implant sites with piezosurgery compared to conventional drilling, and secondarily to evaluate if initial crestal soft tissue thickness could have an impact on marginal bone loss. The present article is reported according to the CONSORT statement ( http://www.consort-statement.org/ ) and its extension checklist for reporting within person randomised trials ( http://www.consort-statement.org/extensions/overview/withinperson ) to improve the quality of reports of within person randomised controlled trials. MATERIALS AND METHODS Trial design This was a single-centre randomised controlled trial (RCT) of split-mouth design and blind assessment. Each patient received two identical implants (one test and one control implant): test implants were placed after having prepared the site with a piezoelectric device while control implants were placed in sites prepared with conventional drills. Patient Selection Any patient requiring at least two single implant-supported crowns in molar or premolar areas (wisdom teeth excluded), being at least 18 years old and able to understand and sign an informed consent form was eligible for inclusion. The two implant sites could be adjacent and had to allow the placement of two implants 11 mm long and 4.0 mm wide i.e. they had to have a bone height of at least 12 mm and a width of at least 7 mm. For patients with more than two suitable implant sites, the operator chose those two sites with more similar characteristics at the screening visit. The operator coded the selected sites as implant site number 1 and implant site number 2. Exclusion criteria were: general contraindications to implant surgery; systemic diseases; immunosuppressed or immunocompromised patients; irradiation in the head and/or neck area; pregnancy or lactating; smokers; untreated periodontitis; poor oral hygiene and motivation (full-mouth plaque and bleeding scores less or equal to15%); substance abusers; psychiatric disorders; acute infection or suppuration at any of the sites intended for implant placement; need of any type of bone augmentation at implant placement; post-extractive sites (implants can be inserted after a healing of at least 6 months); unable to commit to 5-year follow-up; under treatment or had previous treatment with intravenous amino-bisphosphonates; patients referred only for implant placement if the follow-up cannot be done at the treatment centre; participation to other clinical studies if the present protocol could not be fully adhered to. The study protocol was approved by the University of Mainz Ethics Committee (Ethics Committee No.: 837.1 85.1 5 (9953). Patients were recruited and treated by AA at the Department of Operative Dentistry and Periodontology of the University Medical Center (Mainz, Germany) using similar and standardised procedures. Prior to enrolment, all patients were asked to read, and once understood, to sign an informed consent formto document that they understood the scope of the study (including procedures, follow-up evaluations, and any potential risks involved), were allowed opportunities to ask questions pertaining to this study, and were apprised of treatment alternatives. All procedures were performed in accordance with the principles outlined in the Declaration of Helsinki. The study was open to any qualifying patients without regard to sex or race. Clinical procedures Preoperative panoramic radiographs were taken. Patients received a single dose of prophylactic antibiotic 1 hour prior to the intervention: 1 g of amoxicillin or 600 mg of clindamycin, if allergic to penicillin. Patients rinsed with chlorhexidine mouthwash 0.2% for 1 minute prior to the intervention. Patients were treated under local anaesthesia using articaine with adrenaline 1:100.000. After crestal incision, flap elevation was performed first vestibulary, and the thickness of the supracrestal mucosa was measured with a periodontal probe at the incision site ( Fig 1 ). Thereafter the lingual/palatal flap was raised. The sequentially numbered sealed envelope corresponding to the patient recruitment number was opened and implant site number 1 was treated according to the content of the envelope. Consequently, implant site number 2 was treated with the other procedure, according to a split-mouth design. The two study implants were placed in the same surgical session following similar procedures and were restored simultaneously with similar single crowns. Implant sites, randomly allocated to piezo instrumentation, were prepared using piezo-electric device (PIEZOSURGERY touch, Mectron, Cherasco, Italy), starting with a special tip for the initial preparation (IM1S Mectron) followed by IM2, IM3, IM3-4, P3-4 tipsby Mectron; Fig 2 ). Control sites per prepared using a sequence of conventional drills ( Fig 3 ) as described by the manufacturer (VECTODrill Thommen Medical, Grenchen, Switzerland). Cylindrical SPI Element INICELL (Thommen) titanium grade 4 implants with a polished collar of 1 mm height and internal flat to flat hexagon connection were used ( Fig 4 ). All implants were 11 mm long by 4 mm in diameter. Implants were placed by setting the motor with a torque of 30 Ncm. The neck of the implant was placed flush to the surrounding bone. At this point implant stability was measured by a blinded assessor (E.S.) using the Osstell Mentor RFA device (Osstell, Integration Diagnostics, Goteborg, Sweden) using the dedicated transducers (SmartPeg, Osstell) for the SPI 4.0 mm connection. All implants were measured twice (from mesio-distal and bucco-lingual directions). Finally, healing abutments were connected and flaps were sutured with 6.0 sutures (Premilene B/Braun Aesculap, Tuttlingen, Germany) around the abutments. Baseline periapical radiographs were taken (Fig 5a-d ) and if the peri-implant marginal bone levels were difficult to be evaluated another periapical radiograph was taken. Ibuprofen 600 mg was prescribed to be taken thrice a day during meals, for 3 days. In case of stomach problems or allergy to non-steroidal anti-inflammatory drugs, 1g of paracetamol was recommended instead. Patients were instructed to use 0.12% chlorhexidine mouthwash for one minute thrice a day for 1 week, and to avoid brushing and possible trauma on the surgical sites. After 1 week, patients were checked, sutures were removed and oral hygiene instructions were delivered. Implants were left to heal unloaded for 6 months ( Fig 6a ), and six months after surgery, implant level digital impressions were taken, screw-retained metal-ceramic crowns were fabricated on customised titanium abutments and delivered within 2 weeks ( Fig 6b and c ). Periapical radiographs were taken ( Fig 6d ), and oral hygiene instructions were delivered. Exactly the same procedures were implemented at both implants during the same sessions. Patients were recalled for maintenance every 3 months for the entire duration of the study. Outcome measures This study tested the null hypothesis that there were no differences in clinical outcome between the two procedures against the alternative hypothesis of a difference. Outcome measures were: Implant/crown failures: implant mobility, removal of stable implants dictated by progressive marginal bone loss or infection, and any mechanical complications rendering the implant not usable (e.g. implant fracture) were considered implant failures. If a definitive crown had to be replaced for any reason, it accounted as a crown failure. The stability of individual implants was assessed clinically by attempting to rock the crown with the metal handles of two dental instruments at each follow-up visit. Any biological or biomechanical complications. Examples of biological complications are fistula and peri-implantitis. Examples of biomechanical complications are loosening or fracture of the abutment screw. Peri-implant marginal bone level changes evaluated on digital periapical radiographs taken with the paralleling technique at implant placement, 1 ( Fig. 5d ), 3, 6 ( Fig. 6d ), 12, 24 months and at 5 years ( Fig. 7a-c ) after initial implant placement. In case of an unreadable radiograph, a second radiograph was obtained. Peri-implant marginal bone levels were measured using the Planmeca software (Helsinki, Finland). The software was calibrated for every single image using the known implant diameter. Measurements of the mesial and distal bone crest level adjacent to each implant were made to the nearest 0.01 mm. Reference points for the linear measurements were the coronal margin of the implant collar and the most coronal point of visible bone-to-implant contact. The measurements at mesial and distal sides of each implants were averaged at implant level and then at group level. Resonance frequency analysis (RFA): Stability of individual implants was also measured with Osstell Mentor RFA device (Osstell, Integration Diagnostics) using the dedicated transducers (SmartPeg, Osstell) for the SPI 4.0 mm connection. All implants were measured twice (from mesio-distal and bucco-lingual directions and the two measurements were averaged) at implant placement, 1, 3 and 6 months after implant placement. Time needed to prepare the implant site: it was calculated in seconds by a dental assistant starting from the use of the first osteotomy instrument to the complete seating of the implant. A blind outcome assessor (E.S.) assessed implant stability (RFA) and another blinded dentist (V.F.) measured marginal bone levels. Complications were handled and reported directly by the responsible clinician who was not blinded. Sample size, randomisation and allocation concealment A sample size was estimated in 47 implants, given an effect size d= 0.487065, 𝛂 err prob 0.05, and power (1-ß err prob=0.90). Effect size was determined based on a previous similar study reporting ISQ values of 75.7±5.2 in the piezosurgery and 73.3±4.6 in the conventional drilling group at 3 months (2). Due to the split-mouth design of the study, patients provided both test (piezosurgery) and control (conventional drilling) implants. In order to avoid underpowered results (<90%), unbalanced groups and to account for possible drop-outs, three implants were added, scoring a total sample size of 50 implants (25 patients). One computer generated restricted randomisation lists was created. Only one investigator (K.S.), who was not involved in the selection and treatment of the patients, knew the random sequence and had access to the random list stored in a pass-word protected portable computer. The random codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. After flap elevation, the envelope corresponding to the patient recruitment number was opened, and implant site number 1 was allocated to the group determined by the content of the envelope, and other site received the alternative intervention. Therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients. Statistical analysis All data analysis was performed according to a pre-established analysis plan by a dentist (JB) with expertise in statistics who analysed the data without knowledge of the group codes. The implant sites were the statistical unit of the analyses. Differences between the groups in crown/implant failures and complications (dichotomous outcomes) were compared using a McNemar test. Between-group differences for continuous outcomes (mean marginal bone level and RFA) at different time points were estimated by paired t-test. Comparisons between the various follow-up endpoints and the baseline measurements were made by paired t-tests, to detect any changes in mean marginal bone level for each study group. Two-level (patient and implant) mixed effect models with patient as random effect for each time point after implant placement with baseline (implant placement) as a covariate were created to estimate between-group differences for mean marginal bone level and RFA changes from baseline. A further two-level (patient and implant) mixed effect model with patient as random effect was created to evaluate the soft tissue thickness as predictor of marginal bone level changes over time adjusted for baseline ISQ values. All statistical comparisons were conducted at the 0.05 level of significance. RESULTS Thirty patients were screened and 25 patients were consecutively enrolled in this trial. Five patients were not included because they did not have sufficient bone volumes to receive 11 x 4 mm implants. All patients were treated according to the allocated interventions. No patient dropped-out and data from all timepoints could be collected. The data of all patients were evaluated in the statistical analyses. No deviations from the protocol were reported. Patients were recruited and received the implants from May 2015 to May 2016. The follow-up of all patients was to 5 years after implant placement. There were 14 males and 11 females, with a mean age of 47.2 years (range 32 to 73). Implant site characteristics by study groups are described in Table 1 . There were no apparent significant baseline imbalances between the two groups. Table 1 Implant site characteristics. Piezo N = 25 Rotary N = 25 Implants in first premolar position 1 (4%) 1 (4%) Implants in second premolar position 6 (24%) 2 (8%) Implants in first molar position 15 (60%) 13 (52%) Implants in second molar position 3 (12%) 9 (36%) Implants in third molar position 0 (0%) 0 (0%) Implants in maxillae 12 (48%) 12 (48%) Implants in mandibles 13 (52%) 13 (52%) Mucosa thickness at crestal level [Mean (SD)] in mm 2.9 (0.82) 2.98 (0.86) Crowns and implant failures: No implant or crown failed. Complications: Only one complication occurred at one implant of the piezo group (crown screw loosening). There was no statistically significant difference in number of patients experiencing complications between the two groups (difference in proportions = 0.04; P (McNemar test) = 1). Peri-implant marginal bone levels (Table 2 ) and changes (Table 3 ). At implant insertion time (baseline), peri-implant marginal bone levels were 0.49 ± 0.31 mm at piezo sites and 0.41 ± 0.22 mm at drilled sites, the difference being not statistically significant (difference = -0.08 mm; 95% CI -0.21 to 0.06; P (paired t-test) = 0.2577; Table 2 ). Statistically significant differences in favour of drilled sites were observed at 3 months (0.17 mm), 6 months, 1, 2 and 5 years after implant placement (0.14 mm, at each time intervals; Table 2 ). Table 2 Mean radiographic peri-implant marginal bone levels and differences between groups and time periods up to 5 years after implant placement. Implant placement 1 month 3 months 6 months 1 year 2 years 5 years N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] Piezo 25 0.49 (0.31) [0.36;0.61] 25 0.78 (0.36) [0.64;0.93] 25 0.98 (0.35) [0.84;1.13] 25 1.06 (0.37) [0.91;1.22] 25 1.25 (0.36) [1.11;1.40] 25 1.26 (0.35) [1.11;1.40] 25 1.23 (0.33) [1.09;1.37] Drill 25 0.41 (0.22) [0.32;0.50] 25 0.65 (0.36) [0.50;0.80] 25 0.81 (0.34) [0.67;0.95] 25 0.92 (0.39) [0.76;1.08] 25 1.11 (0.38) [0.96;1.27] 25 1.12 (0.37) [0.96;1.27] 25 1.09 (0.35) [0.94;1.23] Difference [95% CI] -0.08 [-0.21;0.06] -0.13 [-0.28;0.01] -0.17 [-0.32;-0.02] -0.14 [-0.27;-0.01] -0.14 [-0.28;-0.01] -0.14 [-0.28;-0.01 -0.14 [-0.28;-0.01 P-value 0.2577 0.0725 0.0266* 0.0359* 0.0455* 0.0459* 0.0459* *Statistically significant difference between groups. Table 3 Mean radiographic peri-implant marginal bone level changes between groups and time periods up to 5 years after implant placement. Implant placement – 1 month Implant placement − 3 months Implant placement − 6 months Implant placement − 1 year Implant placement − 2 years Implant placement − 5 years N Mean (SE) [95% CI] N Mean (SE) [95% CI] N Mean (SE) [95% CI] N Mean (SE) [95% CI] N Mean (SE) [95% CI] N Mean (SE) [95% CI] Piezo 25 0.30 (0.07) [0.15;0.44] 25 0.50 (0.08) [0.33;0.67] 25 0.58 (0.07) [0.42;0.73] 25 0.77 (0.08) [0.60;0.94] 25 0.77 (0.08) [0.60;0.94] 25 0.74 (0.08) [0.58;0.91] Drill 25 0.24 (0.07) [0.11;0.38] 25 0.40 (0.08) [0.24;0.56] 25 0.51 (0.07) [0.35;0.66] 25 0.70 (0.07) [0.55;0.86] 25 0.71 (0.07) [0.56;0.86] 25 0.68 (0.07) [0.53;0.82] Difference* [95% CI] -0.09 [-0.22;0.04] -0.16 (-0.31;-0.01) -0.10 [-0.21;0.01] -0.11 [-0.23;0.01] -0.11 [-0.23;0.01] -0.11 [-0.24;0.01] P-value* 0.178 0.045** 0.082 0.091 0.092 0.083 *Two-level mixed effect with patient as random effect at 1, 3 and 6 months, 1, 2 and 5 years after implant placement with baseline (implant placement) as a covariate; **Statistically significant difference between groups. All changes from baseline (implant placement) statistically significant (P < 0.05). At 5-year post-placement peri-implant bone loss was 0.74 ± 0.08 mm at piezo sites and 0.68 ± 0.07 mm at drilled sites, the difference being not statistically significant (difference = -0.11 mm; 95% CI -0.24 to 0.01; P (paired t-test) = 0.083; Table 3 ). Only at 3 months post-placement was noticed a statistically significant difference in favour of drilled sites (difference = -0.16 mm; 95% CI -0.31 to -0.01; P (paired t-test) = 0.03; Table 3 ). Marginal bone loss from baseline was statistically significant in both groups (P (paired t-test) < 0.05; Table 3 ). Soft tissue thickness did not result to be statistically significantly affecting marginal bone level changes (estimate = 0.05; 95% CI -0.03; 0.12; P = 0.239) over time in the mixed effect model adjusted for baseline ISQ values (Table 4 ). Table 4 Mixed effect model for mean radiographic peri-implant marginal bone level changes between groups and time periods up to 5 years after implant placement with soft tissue thickness as baseline covariate. Term Estimate SE 95% Lower 95% Upper P-value Intercept 0.77 0.26 0.26 1.27 0.0030* ISQ at implant placement 0.001 0.003 -0.01 0.01 0.8454 Soft tissue thickness 0.05 0.04 -0.03 0.12 0.2393 Time point (1 month) -0.22 0.03 -0.28 -0.2 < .0001* Time point (3 months) -0.04 0.03 -0.1 0.02 0.1710 Time point (6 months) 0.05 0.03 -0.01 0.11 0.1112 Time point (12 months) 0.24 0.03 0.18 0.31 < .0001* Time point (24 months) 0.25 0.03 0.19 0.31 < .0001* Time point (5 years) 0.22 0.03 0.16 0.28 < .0001* Site preparation with piezo 0.07 0.01 0.04 0.10 < .0001* Two-level mixed effect with patient as random effect with baseline ISQ values, soft tissue thickness as a covariates; and site preparation method and time points as factors; *Statistically significant estimate. Resonance frequency analysis (RFA) values (Table 5 ) and changes (Table 6 ). At implant insertion time (baseline), RFA values were 70.98 ± 10.38 at piezo sites and 70.82 ± 9.21 at drilled sites, the difference being not statistically significant (difference = -0.16; 95% CI -3.61 to 3.29; P (paired t-test) = 0.9245; Table 5 ). At 6 months post-placement, RFA change was 3.94 ± 2.11 at piezo sites and 3.7 ± 2.06 at drilled sites, the difference being not statistically significant (difference = -0.35; 95% CI -1.95 to 1.25; P (paired t-test) = 0.672; Table 6 ). RFA changes from baseline were not statistically significant in both groups (Table 6 ). The average time needed to prepare the implant site was of 329.44 ± 134.65 sec for the piezo group and 92.64 ± 52.60 sec for the drill group, showing a statistically significant difference in favour of the conventional drilling procedure (difference = -236.8 sec; 95% CI -286.12 to -187.48; P < 0.0001). Table 5 Mean RFA values between groups and time periods up to 6 months after implant placement. Implant placement 1 month 3 months 6 months N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] N Mean (SD) [95% CI] Piezo 25 70.98 (10.38) [66.69;75.27] 25 69.05 (16.26) [62.33;75.75] 25 73.96 (10.16) [69.76;78.16] 25 74.82 (9.74) [70.90;78.94] Drill 25 70.82 (9.21) [67.02;74.62] 25 70.68 (13.48) [65.12;76.24] 25 73.4 (12.87) [68.09;78.71] 25 74.52 (12.61) [69.32;79.72] Difference [95% CI] 25 -0.16 [-3.61;3.29] 25 1.65[-1.30;4.58] 25 -0.56 [-2.42;1.30] 25 − 0.4[-2.23;1.43] P-value 0.9245 0.2615 0.5397 0.6554 Table 6 Mean RFA values changes between groups and time periods up to 6 months after implant placement. Implant placement – 1 month Implant placement − 3 months Implant placement − 6 months N Mean (SE) [95% CI] N Mean (SE) [95% CI] N Mean (SE) [95% CI] Piezo 25 -1.94 (2.77) [-7.67;3.79] 25 2.98 (2.05) [-1.24;7.20] 25 3.94 (2.11) [-0.41;8.29] Drill 25 -0.14 (2.18) [-4.65;4.37] 25 2.58 (2.05) [-1.66;6.82] 25 3.7 (2.06) [-0.56;7.96] Difference* [95% CI] 1.71 [-1.15;4.56] -0.51 (-2.10;1.09) -0.35 [-1.95;1.25] P-value* 0.254 0.540 0.672 *Two-level mixed effect with patient as random effect at 1, 3 and 6 months after implant placement with baseline (implant placement) as a covariate. All changes from baseline (implant placement) non-statistically significant. DISCUSSION This trial was designed to evaluate whether it could be more advantageous to prepare implant sites with piezosurgery when compared to conventional drilling. Apart some statistically significant differences in peri-implant bone level/loss favouring drilling in the range of 0.14 to 0.17 mm observed at different timepoints, but not having a clinically significant impact, the only statistical difference having a clinical significance was the need of about 4 minutes more to finalise the implantation procedure using piezosurgery. Despite that some may not consider this difference as clinically relevant, we cannot see any advantage in prolonging of 4 minutes the surgical time requested to complete the implantation procedure at each implant site using piezosurgery, especially in case of placement of multiple implants. Our findings are, generally speaking, in agreement with those of other RCTs testing similar hypotheses. No difference for implant success rates and peri-implant bone loss were observed in a large multicentre RCT of split-mouth design ( 6 ). No difference in implants stability measured with RFA was found in another split-mouth RCT( 7 ). Also another more detailed split-mouth RCT find no significant differences in peri-implant bone loss with the exception of a bit more pain perceived after 2 and 7 days at drilled sites ( 8 ). A study, possibly randomized and of parallel group design, reported longer preparation time with piezosurgery but less postoperative pain at day 1 and 2 as well as less swelling at day one and no differences thereafter, and no differences in bone loss ( 9 ). A split-mouth RCT comparing conventional drilling versus conventional drilling plus piezosurgery (the last 2 tips), found the only statistically significant difference at 8 weeks post-implantation for stability assessed with RFA favouring conventional drilling plus piezosurgery and no difference in radiographic bone loss 1 year after loading ( 2 ). However, such a difference in stability may not have a clinical impact. Another similar trial found no difference as well ( 10 ) but significant longer preparation times using piezosurgery Our findings are in disagreement with the findings from the group who invented piezosurgery( 1 ), who presented a significantly higher loss in percentage of implant stability measured with RFA in favour of piezosurgery up to 56 days post-implantation, without evaluating other outcome measures, as well as with the findings of another group ( 11 ). Another, possibly split-mouth, RCT reported higher implant stability values assessed with RFA favouring piezosurgery prepared sites, no differences in peri-implant bone loss and bone density, and an average of 2 minutes more needed when using piezosurgery ( 12 ). Another split-mouth RCT, compared piezosurgery versus rotary drills for placing zygomatic implants ( 13 ). Zygomatic implants, as the name suggests, are placed in zygomatic bone, that is harder than maxillary bone. While the post-surgical haematoma was larger at drilled sites, the preparation of 10% of the sites allocated to piezosurgery was unsuccessful, so drills had to be used instead. This suggests that a combined use of conventional drills and piezosurgery, when indicated, could be advantageous at least for the placement of zygomatic implants. No particular advantages were observed when using piezosurgery as an alternative to rotary drills to prepare implant sites, however in the proximity of the alveolar inferior nerve, piezosurgery might be an interesting alternative since potentially less damaging than conventional drilling, however this hypothesis should be tested in properly designed and conducted RCTs. Regarding the secondary hypothesis tested in this study, i.e. to evaluate whether crestal mucosa thickness could have an effect on bone loss, we found no effect. Our findings are in agreement with the findings/conclusions of some studies( 14 – 16 ), but disagreement with other similar studies ( 17 – 22 ). These differences may be partially explained by the a not impressive variation in mucosa thickness in our study ranging from 1.5 to 5 mm with only five sites having a thickness of 1.5 mm, by the long-term data of our study compared to the short-term data usually published, and by the methodological flaws/bias affecting the majority of studies published on this topic. The main limitations of the present trial were not having investigated the patients’ post-implantation view/preference about the two different preparation techniques, and the strict inclusion criteria which may limit the generalisability of the results, for instance to smokers. Nevertheless, since both procedures were tested in real clinical conditions, results can be generalized with confidence to a wider population having similar characteristics. CONCLUSIONS No clinically appreciable differences were noticed when placing implants with piezosurgery or rotary instruments, however piezosurgery required on average 4 minutes more than conventional drills. No effect of initial crestal soft tissue thickness was observed on peri-implant bone loss. Declarations Ethics approval and consent to participate The study protocol was approved by the University of Mainz Ethics Committee (Ethics Committee No.: 837.1 85.1 5 (9953)). All patients signed a specifically informed consent that was approved by the ethical committee in order to participate in the present trial Consent for publication Not applicable. Availability of data and material Data can be available on direct request via email to the corresponding author. Competing interests Authors stated explicitly that there are no conflicts of interest in connection with this article. Funding Thommen Medical (Grenchen, Switzerland), the manufacturer of the implants used in this investigation, partially funded this trial and donated the implants, however data belonged to the authors and by no means the sponsor interfered with the conduct of the trial or the publication of its results. The study was supported by Department of Periodontology and Operative Dentistry of Johannes Gutenberg University of Mainz. Authors' contributions AA, KS and BA conceived the idea; AA performed all surgeries; VF collected the data; JB and ME analysed the data; and ME led the writing. Acknowledgments The authors wish to express their gratitude to Prof. Dr. Brita Willershausen for her contribution in study design and Nelly Kary for enrolling the patients. Conflict of interest statement: and the authors have stated explicitly that there are no conflicts of interest in connection with this article. References Stacchi C, Vercellotti T, Torelli L, Furlan F, Di Lenarda R. Changes in implant stability using different site preparation techniques: twist drills versus piezosurgery. A single-blinded, randomized, controlled clinical trial. Clinical Implant Dentistry and Related Research 2013;15:188-197. Canullo L, Penarrocha D, Penarrocha M, Rocio AG, Penarrocha-Diago M. Piezoelectric vs. conventional drilling in implant site preparation: pilot controlled randomized clinical trial with crossover design. Clinical Oral Implants Research 2014;25:1336-1343. Vercellotti T, Nevins ML, Kim DM, Nevins M, Wada K, Schenk RK, et al. Osseous response following resective therapy with piezosurgery. International Journal of Periodontics and Restorative Dentistry 2005;25:543-549. Bengazi F, Lang NP, Canciani E, Vigano P, Velez JU, Botticelli D. Osseointegration of implants with dendrimers surface characteristics installed conventionally or with Piezosurgery(R). A comparative study in the dog. Clinal Oral Implants Research 2014;25:10-15. Sagheb K, Kumar VV, Azaripour A, Walter C, Al-Nawas B, Kammerer PW. Comparison of conventional twist drill protocol and piezosurgery for implant insertion: an ex vivo study on different bone types. Clinical Oral Implants Research 2017;28:207-213. Stacchi C, Lombardi T, Baldi D, Bugea C, Rapani A, Perinetti G, et al. Immediate loading of implant-supported single crowns after conventional and ultrasonic implant site preparation: A multicenter randomized controlled clinical trial. BioMed research international 2018;2018:6817154. Soheilifar S, Bidgoli M, Houshyar E, Farhadian M, Ghamari A. Comparing the effect of preparation of the implant sites with piezosurgery and conventional drilling on the stability of implants at 5-months follow-up. Journal of long-term effects of medical implants 2018;28:1-8. Peker Tekdal G, Bostanci N, Belibasakis GN, Gurkan A. The effect of piezoelectric surgery implant osteotomy on radiological and molecular parameters of peri-implant crestal bone loss: a randomized, controlled, split-mouth trial. Clinical Oral Implants Research 2016;27:535-544. Scarano A, Carinci F, Lorusso F, Festa F, Bevilacqua L, Santos de Oliveira P, et al. Ultrasonic vs Drill Implant Site Preparation: Post-Operative Pain Measurement Through VAS, Swelling and Crestal Bone Remodeling: A Randomized Clinical Study. Materials 2018;11. Alattar AN, Bede SYH. Does mixed conventional/piezosurgery implant site preparation affect implant stability? The Journal of craniofacial surgery 2018;29:e472-e475. da Silva Neto UT, Joly JC, Gehrke SA. Clinical analysis of the stability of dental implants after preparation of the site by conventional drilling or piezosurgery. The British journal of oral & maxillofacial surgery 2014;52:149-153. Sallam HM, Khalifa GA, Khalifa FA. Dynamics of implant site preparation affecting the quality of osseointegrated implants in the maxillary aesthetic zone. J Craniomaxillofacial Surg 2020;48:645-652. Pistilli R, Esposito M, Barausse C, Balercia A, Bonifazi L, Buti J, et al. Conventional drills versus piezoelectric surgery preparation for placement of four immediately loaded zygomatic oncology implants in edentulous maxillae: results from a 3-year within person randomised controlled trial. Clinical Trials in Dentistry 2020;2:5-17. Akcali A, Trullenque-Eriksson A, Sun C, Petrie A, Nibali L, Donos N. What is the effect of soft tissue thickness on crestal bone loss around dental implants? A systematic review. Clinical Oral Implants Research 2017;28:1046-1053. Spinato S, Stacchi C, Lombardi T, Bernardello F, Messina M, Dovigo S, et al. Influence of abutment height and vertical mucosal thickness on early marginal bone loss around implants: A randomised clinical trial with an 18-month post-loading clinical and radiographic evaluation. International Journal of Oral Implantology (Berl) 2020;13:279-290. Munoz M, Busoms E, Vilarrasa J, Albertini M, Ruiz-Magaz V, Nart J. Bone-level changes around implants with 1- or 3-mm-high abutments and their relation to crestal mucosal thickness: A 1-year randomized clinical trial. Journal of Clinical Periodontology 2021;48:1302-1311. Linkevicius T, Puisys A, Linkeviciene L, Peciuliene V, Schlee M. Crestal bone stability around implants with horizontally matching connection after soft tissue thickening: A prospective clinical trial. Clinical Implant Dentistry and Related Research 2015;17:497-508. Puisys A, Linkevicius T. The influence of mucosal tissue thickening on crestal bone stability around bone-level implants. A prospective controlled clinical trial. Clinical Oral Implants Research 2015;26:123-129. Linkevicius T, Puisys A, Steigmann M, Vindasiute E, Linkeviciene L. Influence of vertical soft tissue thickness on crestal bone changes around Implants with platform switching: A comparative clinical study. Clinical Implant Dentistry and Related Research 2015;17:1228-1236. Suarez-Lopez Del Amo F, Lin GH, Monje A, Galindo-Moreno P, Wang HL. Influence of soft tissue thickness on peri-implant marginal bone loss: A systematic review and meta-analysis. Journal of Periodontology 2016;87:690-699. van Eekeren P, van Elsas P, Tahmaseb A, Wismeijer D. The influence of initial mucosal thickness on crestal bone change in similar macrogeometrical implants: a prospective randomized clinical trial. Clinical Oral Implants Research 2017;28:214-218. Di Gianfilippo R, Valente NA, Toti P, Wang HL, Barone A. Influence of implant mucosal thickness on early bone loss: a systematic review with meta-analysis. Journal of periodontal & implant science 2020;50:209-225. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 05 Nov, 2024 Reviews received at journal 25 Oct, 2024 Reviews received at journal 23 Oct, 2024 Reviewers agreed at journal 18 Oct, 2024 Reviewers agreed at journal 18 Oct, 2024 Reviewers invited by journal 18 Oct, 2024 Editor assigned by journal 18 Oct, 2024 Submission checks completed at journal 17 Oct, 2024 First submitted to journal 16 Oct, 2024 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. 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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-5278685","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":367737495,"identity":"30eefff9-320f-4151-8ca7-0f6c87c2b787","order_by":0,"name":"Adriano Azaripour","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7UlEQVRIiWNgGAWjYFCCBIYDUBbjYzDFzNxAtBZmYwYGAyDFSFgLDLBJg7UwENDC35778MDPHTby8v2Hj1UXVPyJ5m8HavlRsQ2nFokzzw0O9p5JM9xwIy3t9owzBrkzDjM2MPacuY3bmhtpDAd42w4zbpDgMbvN22aQ2wDUwszYhluLPFDLwb9th+3n958xKwZpmU9IiwFQy2GgLYkNB3LMmEFaNhDSYnjmGcNh2ba0ZKBfkqV5zhjnbgRqOYjPL3LH05g/vm2zsZ3ff/jgZ54Kudx55w8ffPCjAo/3sYIDJKofBaNgFIyCUYAGAII8XNL+b+rYAAAAAElFTkSuQmCC","orcid":"","institution":"University Medical Center, Johannes Gutenberg University","correspondingAuthor":true,"prefix":"","firstName":"Adriano","middleName":"","lastName":"Azaripour","suffix":""},{"id":367737496,"identity":"ab0147a6-049c-4ea6-a6ca-08de9a0277de","order_by":1,"name":"Vittorio Farina","email":"","orcid":"","institution":"Private practice","correspondingAuthor":false,"prefix":"","firstName":"Vittorio","middleName":"","lastName":"Farina","suffix":""},{"id":367737497,"identity":"aceb06cf-ff5e-4efa-a22e-7b8d08bc4abb","order_by":2,"name":"Marco Esposito","email":"","orcid":"","institution":"IRCCS San Raffaele Scientific Institute and Vita-Salute San Raffaele University","correspondingAuthor":false,"prefix":"","firstName":"Marco","middleName":"","lastName":"Esposito","suffix":""},{"id":367737498,"identity":"1fa8da59-77d8-4c40-83a7-76fa5a59f937","order_by":3,"name":"Jacopo Buti","email":"","orcid":"","institution":"UCL Eastman Dental Institute","correspondingAuthor":false,"prefix":"","firstName":"Jacopo","middleName":"","lastName":"Buti","suffix":""},{"id":367737499,"identity":"ae0d9da9-4fb3-437b-b7f3-dc496cd16ddd","order_by":4,"name":"Bilal Al-Nawas","email":"","orcid":"","institution":"University Medical Center, Johannes Gutenberg University","correspondingAuthor":false,"prefix":"","firstName":"Bilal","middleName":"","lastName":"Al-Nawas","suffix":""},{"id":367737500,"identity":"3ad25b81-6a39-45af-9857-0c7ef5c98f97","order_by":5,"name":"Keyvan Sagheb","email":"","orcid":"","institution":"University Medical Center, Johannes Gutenberg University","correspondingAuthor":false,"prefix":"","firstName":"Keyvan","middleName":"","lastName":"Sagheb","suffix":""}],"badges":[],"createdAt":"2024-10-17 00:23:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5278685/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5278685/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":67288220,"identity":"acfee79b-8f36-4a05-9542-bf9581f36bd2","added_by":"auto","created_at":"2024-10-23 09:47:40","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":344657,"visible":true,"origin":"","legend":"\u003cp\u003eMeasurement of the mucosa height\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/198d46906426ed7aad4b3e99.png"},{"id":67287648,"identity":"bc6c5230-62c8-4d24-84ff-30dbc935230a","added_by":"auto","created_at":"2024-10-23 09:39:40","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":59981,"visible":true,"origin":"","legend":"\u003cp\u003eSequence of piezoelectric inserts used to prepared the test implant sites\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/022dc2c38105439c26e79c9a.png"},{"id":67289887,"identity":"33a0b71e-8c87-4db3-9c44-b84fbcb7197b","added_by":"auto","created_at":"2024-10-23 09:55:40","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":44131,"visible":true,"origin":"","legend":"\u003cp\u003eSequence of drills used to prepare the control implant sites.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/fb15bec0d49f3cd686b06cc7.png"},{"id":67288219,"identity":"56d9c0cb-15b1-4033-bbfc-0dbc2e131d44","added_by":"auto","created_at":"2024-10-23 09:47:40","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":40558,"visible":true,"origin":"","legend":"\u003cp\u003eIllustration showing the implant design used in the study\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/8fd066219e2003ff4abcaf7b.png"},{"id":67287652,"identity":"bfbe1420-af55-4e1a-9d5b-0f0468211f17","added_by":"auto","created_at":"2024-10-23 09:39:40","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":533789,"visible":true,"origin":"","legend":"\u003cp\u003ea) preoperative view of a representative patient; b) site 15 was randomly allocated to piezosurgery and site 16 to conventional drilling; c) flap closure; d) postoperative baseline periapical radiograph.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/69fbc6ec0dbd17750d0b2192.png"},{"id":67288222,"identity":"de675cf8-0901-467c-bd8a-8a4a7e857216","added_by":"auto","created_at":"2024-10-23 09:47:40","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":456450,"visible":true,"origin":"","legend":"\u003cp\u003ea) clinical situation prior to delivery of definitive crowns; b) occlusal and c) vestibular view at delivery of definitive crowns; d) periapical radiograph at initial loading (6 months after implant placement).\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/52ee357f9e8bfbb72b1dc075.png"},{"id":67287654,"identity":"5676bf0b-754f-4cc4-90c3-afd56a9234d3","added_by":"auto","created_at":"2024-10-23 09:39:40","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":369961,"visible":true,"origin":"","legend":"\u003cp\u003ea) and b) clinical and c) radiographic images at 5 years after placement.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/4e5bc73092ca410d6fee30e2.png"},{"id":67290228,"identity":"5086031a-7204-48c2-ac6d-4ee9e46d416c","added_by":"auto","created_at":"2024-10-23 10:03:41","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3105231,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5278685/v1/acb1d82f-e4c2-4b7a-ab0f-b0e2a9df0a38.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Dental implant site preparation with conventional rotary drill or piezosurgery: five-year after placement results from a within person randomised controlled trial","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eAmong the numerous ongoing debates in implant dentistry there is also the one about which could be the best way to prepare implants sites for placing dental implants. Traditionally, implant sites were prepared by a sequence of drills of increased diameters, the last diameter depending on the implant diameter, the quality of bone and the wished insertion torque. Despite that rotary drills are almost universally used for implant sites preparation, some authors suggested the use of piezosurgery instead, either alone (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) or in combination with rotary drills (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). The hypothesis behind is that piezosurgery may induce a more precise cut as well as inducing less heating, therefore decreasing the risk of bone necrosis and improving bone healing compared to rotary drills (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). At the same time, piezosurgery can be less aggressive than rotary drills if a nerve is accidentally hit. On the other hand, an animal study showed a tendency for more bone to implant contact and RFA, believed to corresponds to increased implant stability, at drilled sites when compared to implant sites prepared with piezosurgery (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). In addition, drilling required a 4-minute shorter preparation time and two implants did not integrated in the piezo group versus one in the drilled group (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Another ex-vivo study failed to show any statistically significant differences between drilling and piezosurgery regarding heat generation and implant stability assessed with the resonance frequency analysis (RFA) (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). However, site preparation with piezosurgery took significantly longer time than with rotary drills. Therefore, it would be interesting to know whether a better clinical outcome could be obtained by using piezoelectric surgery instead of conventional drills to prepare dental implant sites.\u003c/p\u003e \u003cp\u003eThe aims of this RCT were primarily to evaluate clinical outcome of preparing implant sites with piezosurgery compared to conventional drilling, and secondarily to evaluate if initial crestal soft tissue thickness could have an impact on marginal bone loss. The present article is reported according to the CONSORT statement (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.consort-statement.org/\u003c/span\u003e\u003cspan address=\"http://www.consort-statement.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) and its extension checklist for reporting within person randomised trials (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.consort-statement.org/extensions/overview/withinperson\u003c/span\u003e\u003cspan address=\"http://www.consort-statement.org/extensions/overview/withinperson\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) to improve the quality of reports of within person randomised controlled trials.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003e\u003cstrong\u003eTrial design\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis was a single-centre randomised controlled trial (RCT) of split-mouth design and blind assessment. Each patient received two identical implants (one test and one control implant): test implants were placed after having prepared the site with a piezoelectric device while control implants were placed in sites prepared with conventional drills.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePatient Selection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAny patient\u0026nbsp;requiring at least two single implant-supported crowns in molar or premolar areas (wisdom teeth excluded), being at least 18 years old and able to understand and sign an informed consent\u0026nbsp;form was eligible\u0026nbsp;for inclusion.\u0026nbsp;The two implant sites could be adjacent and had to allow the placement of two implants 11 mm long and 4.0 mm wide i.e. they had to have a bone height of at least 12 mm and a width of at least 7 mm. For patients with more than two suitable implant sites, the operator chose those two sites with more similar characteristics at the screening visit. The operator coded the selected sites as implant site number 1 and implant site number 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eExclusion criteria were:\u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n \u003cli\u003egeneral contraindications to implant surgery;\u003c/li\u003e\n \u003cli\u003esystemic diseases;\u003c/li\u003e\n \u003cli\u003eimmunosuppressed or immunocompromised patients;\u003c/li\u003e\n \u003cli\u003eirradiation in the head and/or neck area;\u003c/li\u003e\n \u003cli\u003epregnancy or lactating;\u003c/li\u003e\n \u003cli\u003esmokers;\u003c/li\u003e\n \u003cli\u003euntreated periodontitis;\u003c/li\u003e\n \u003cli\u003epoor oral hygiene and motivation (full-mouth plaque and bleeding scores less or equal to15%);\u003c/li\u003e\n \u003cli\u003esubstance abusers;\u003c/li\u003e\n \u003cli\u003epsychiatric disorders;\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eacute infection or suppuration at any of the sites intended for implant placement;\u003c/li\u003e\n \u003cli\u003eneed of any type of bone augmentation at implant placement;\u003c/li\u003e\n \u003cli\u003epost-extractive sites (implants can be inserted after a healing of at least 6 months);\u003c/li\u003e\n \u003cli\u003eunable to commit to 5-year follow-up;\u003c/li\u003e\n \u003cli\u003eunder treatment or had previous treatment with intravenous amino-bisphosphonates;\u003c/li\u003e\n \u003cli\u003epatients referred only for implant placement if the follow-up cannot be done at the treatment centre;\u003c/li\u003e\n \u003cli\u003eparticipation to other clinical studies\u0026nbsp;if the present protocol could not be fully adhered to.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;The study protocol was approved by the University of Mainz Ethics Committee (Ethics Committee No.: 837.1 85.1 5 (9953). Patients were recruited and treated by AA at\u0026nbsp;the Department of Operative Dentistry and Periodontology of the University Medical Center (Mainz, Germany)\u0026nbsp;using similar and standardised procedures. Prior to enrolment, all patients were asked to read, and once understood, to sign an informed consent formto document that they understood the scope of the study (including procedures, follow-up evaluations, and any potential risks involved), were allowed opportunities to ask questions pertaining to this study, and were apprised of treatment alternatives. All procedures were performed in accordance with the principles outlined in the Declaration of Helsinki. The study was open to any qualifying patients without regard to sex or race.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical procedures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePreoperative panoramic radiographs were taken.\u0026nbsp;Patients received a single dose of prophylactic antibiotic 1 hour prior to the intervention: 1 g of amoxicillin or 600 mg of\u0026nbsp;clindamycin,\u0026nbsp;if allergic to penicillin.\u0026nbsp;Patients rinsed with chlorhexidine mouthwash 0.2% for 1 minute prior to the intervention.\u0026nbsp;Patients were treated under local anaesthesia using articaine with adrenaline 1:100.000.\u0026nbsp;After crestal incision, flap elevation was performed first vestibulary, and the thickness of the supracrestal mucosa was measured with a periodontal probe at the incision site (\u003cstrong\u003eFig 1\u003c/strong\u003e). Thereafter the lingual/palatal flap was raised.\u0026nbsp;The sequentially numbered sealed envelope corresponding to the patient recruitment number was opened and\u0026nbsp;implant site number 1 was treated according to the content of the envelope. Consequently, implant site number 2 was treated with the other procedure, according to a split-mouth design. The two study implants were placed in the same surgical session following similar procedures and were restored simultaneously with similar single crowns.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Implant sites, randomly allocated to piezo instrumentation, were prepared using\u0026nbsp;piezo-electric device (PIEZOSURGERY touch, Mectron, Cherasco, Italy), starting with a special tip for the initial preparation (IM1S Mectron) followed by IM2, IM3, IM3-4, P3-4 tipsby Mectron; \u003cstrong\u003eFig 2\u003c/strong\u003e). Control sites per prepared using a sequence of conventional drills (\u003cstrong\u003eFig 3\u003c/strong\u003e) as described by the manufacturer (VECTODrill Thommen Medical, Grenchen, Switzerland). Cylindrical SPI Element INICELL (Thommen) titanium grade 4 implants with a polished collar of 1 mm height and internal flat to flat hexagon connection were used (\u003cstrong\u003eFig 4\u003c/strong\u003e). All implants were 11 mm long by 4 mm in diameter.\u0026nbsp;Implants were placed by setting the motor with a torque of 30 Ncm.\u0026nbsp;The neck of the implant was placed flush to the surrounding bone. At this point implant\u0026nbsp;stability was measured by a blinded assessor (E.S.) using the Osstell Mentor RFA device (Osstell, Integration Diagnostics, Goteborg, Sweden) using the dedicated transducers (SmartPeg, Osstell) for the SPI 4.0 mm connection. All implants were measured twice (from mesio-distal and bucco-lingual directions). Finally, healing abutments were connected and flaps were sutured with 6.0 sutures (Premilene B/Braun Aesculap, Tuttlingen, Germany) around the abutments.\u0026nbsp;Baseline periapical radiographs were taken\u0026nbsp;\u003cstrong\u003e(Fig 5a-d\u003c/strong\u003e) and if the peri-implant marginal bone levels were difficult to be evaluated another periapical radiograph was taken.\u0026nbsp;Ibuprofen 600 mg was prescribed to be taken thrice a day during meals, for 3 days. In case of stomach problems or allergy to non-steroidal anti-inflammatory drugs, 1g of paracetamol was recommended instead. Patients were instructed to use 0.12% chlorhexidine mouthwash for one minute thrice a day for 1 week, and to avoid brushing and possible trauma on the surgical sites. After 1 week, patients were checked, sutures were removed and oral hygiene instructions were delivered.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Implants were left to heal unloaded for 6 months (\u003cstrong\u003eFig 6a\u003c/strong\u003e), and\u0026nbsp;six months after surgery, implant level digital impressions were taken, screw-retained metal-ceramic crowns were fabricated on customised titanium abutments and delivered within 2 weeks (\u003cstrong\u003eFig 6b and c\u003c/strong\u003e).\u0026nbsp;Periapical radiographs were taken (\u003cstrong\u003eFig 6d\u003c/strong\u003e), and oral hygiene instructions were delivered. Exactly the same procedures were implemented at both implants during the same sessions.\u0026nbsp;Patients were recalled for maintenance every 3 months\u0026nbsp;for the entire duration of the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutcome measures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study tested the null hypothesis that there were no differences in clinical outcome between the two procedures against the alternative hypothesis of a difference.\u003c/p\u003e\n\u003cp\u003eOutcome measures were:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eImplant/crown failures: implant mobility, removal of stable implants dictated by progressive marginal bone loss or infection, and any mechanical complications rendering the implant not usable (e.g. implant fracture) were considered implant failures. If a definitive crown had to be replaced for any reason, it accounted as a crown failure. The stability of individual implants was assessed clinically by attempting to rock the crown with the metal handles of two dental instruments at each follow-up visit.\u003c/li\u003e\n \u003cli\u003eAny biological or biomechanical complications.\u0026nbsp;Examples of biological complications are fistula and peri-implantitis. Examples of biomechanical complications are loosening or fracture of the abutment screw.\u003c/li\u003e\n \u003cli\u003ePeri-implant marginal bone level changes evaluated on digital periapical radiographs taken with the paralleling technique at implant placement, 1 (\u003cstrong\u003eFig. 5d\u003c/strong\u003e), 3, 6 (\u003cstrong\u003eFig. 6d\u003c/strong\u003e), 12, 24 months and at 5 years (\u003cstrong\u003eFig. 7a-c\u003c/strong\u003e) after initial implant placement. In case of an unreadable radiograph, a second radiograph was obtained. Peri-implant marginal bone levels were measured using the Planmeca software (Helsinki, Finland). The software was calibrated for every single image using the known implant diameter. Measurements of the mesial and distal bone crest level adjacent to each implant were made to the nearest 0.01 mm. Reference points for the linear measurements were the coronal margin of the implant collar and the most coronal point of visible bone-to-implant contact. The measurements at mesial and distal sides of each implants were averaged at implant level and then at group level.\u003c/li\u003e\n \u003cli\u003eResonance frequency analysis (RFA): Stability of individual implants was also measured with\u0026nbsp;Osstell Mentor RFA device (Osstell, Integration Diagnostics) using the dedicated transducers (SmartPeg, Osstell) for the SPI 4.0 mm connection. All implants were measured twice (from mesio-distal and bucco-lingual directions and the two measurements were averaged)\u0026nbsp;at implant placement, 1, 3 and 6 months after implant placement.\u003c/li\u003e\n \u003cli\u003eTime needed to prepare the implant site: it was calculated in seconds by a dental assistant starting from the use of the first osteotomy instrument to the complete seating of the implant.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eA blind outcome assessor (E.S.) assessed implant stability (RFA) and another blinded dentist (V.F.) measured marginal bone levels. Complications were handled and reported directly by the responsible clinician who was not blinded.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSample size, randomisation and allocation concealment\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA sample size was estimated in 47 implants, given an effect size d=\u0026nbsp;0.487065,\u0026nbsp;𝛂\u0026nbsp;err prob 0.05, and power (1-ß err prob=0.90). Effect size was determined based on a previous similar study reporting ISQ values of 75.7±5.2 in the piezosurgery and 73.3±4.6 in the conventional drilling group at 3 months\u0026nbsp;(2). Due to the split-mouth design of the study, patients provided both test (piezosurgery) and control (conventional drilling) implants. In order to avoid underpowered results (\u0026lt;90%), unbalanced groups and to account for possible drop-outs, three implants were added, scoring a total sample size of 50 implants (25 patients).\u003c/p\u003e\n\u003cp\u003eOne computer generated restricted randomisation lists was created.\u0026nbsp;Only one investigator (K.S.), who was not involved in the selection and treatment of the patients, knew the random sequence and had access to the random list stored in a pass-word protected portable computer.\u0026nbsp;The random codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. After flap elevation, the envelope corresponding to the patient recruitment number was opened, and implant site number 1 was allocated to the group determined by the content of the envelope, and other site received the alternative intervention. Therefore,\u0026nbsp;treatment allocation was concealed to the investigators in charge of enrolling and treating the patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;All data analysis was performed according to a pre-established analysis plan by a dentist (JB) with expertise in statistics who analysed the data without knowledge of the group codes.\u0026nbsp;The implant sites were the statistical unit of the analyses. Differences between the groups in crown/implant failures and complications (dichotomous outcomes) were compared using a McNemar test. Between-group differences for continuous outcomes (mean marginal bone level and RFA) at different time points were estimated by paired t-test. Comparisons between the various follow-up endpoints and the baseline measurements were made by paired t-tests, to detect any changes in mean marginal bone level for each study group. Two-level (patient and implant) mixed effect models with patient as random effect for each time point after implant placement with baseline (implant placement) as a covariate were created to estimate between-group differences for mean marginal bone level and RFA changes from baseline. A further two-level (patient and implant) mixed effect model with patient as random effect was created to evaluate the soft tissue thickness as predictor of marginal bone level changes over time adjusted for baseline ISQ values. All statistical comparisons were conducted at the 0.05 level of significance.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThirty patients were screened and 25 patients were consecutively enrolled in this trial. Five patients were not included because they did not have sufficient bone volumes to receive 11 x 4 mm implants. All patients were treated according to the allocated interventions. No patient dropped-out and data from all timepoints could be collected. The data of all patients were evaluated in the statistical analyses. No deviations from the protocol were reported.\u003c/p\u003e\n\u003cp\u003ePatients were recruited and received the implants from May 2015 to May 2016. The follow-up of all patients was to 5 years after implant placement. There were 14 males and 11 females, with a mean age of 47.2 years (range 32 to 73). Implant site characteristics by study groups are described in Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. There were no apparent significant baseline imbalances between the two groups.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eImplant site characteristics.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePiezo\u003c/p\u003e\n \u003cp\u003eN\u0026thinsp;=\u0026thinsp;25\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRotary\u003c/p\u003e\n \u003cp\u003eN\u0026thinsp;=\u0026thinsp;25\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in first premolar position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in second premolar position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6 (24%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2 (8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in first molar position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15 (60%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (52%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in second molar position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3 (12%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9 (36%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in third molar position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in maxillae\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12 (48%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12 (48%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImplants in mandibles\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (52%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (52%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMucosa thickness at crestal level [Mean (SD)] in mm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.9 (0.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.98 (0.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eCrowns and implant failures: No implant or crown failed.\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eComplications: Only one complication occurred at one implant of the piezo group (crown screw loosening). There was no statistically significant difference in number of patients experiencing complications between the two groups (difference in proportions\u0026thinsp;=\u0026thinsp;0.04; P (McNemar test)\u0026thinsp;=\u0026thinsp;1).\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003ePeri-implant marginal bone levels (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e) and changes (Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). At implant insertion time (baseline), peri-implant marginal bone levels were 0.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.31 mm at piezo sites and 0.41\u0026thinsp;\u0026plusmn;\u0026thinsp;0.22 mm at drilled sites, the difference being not statistically significant (difference = -0.08 mm; 95% CI -0.21 to 0.06; P (paired t-test)\u0026thinsp;=\u0026thinsp;0.2577; Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). Statistically significant differences in favour of drilled sites were observed at 3 months (0.17 mm), 6 months, 1, 2 and 5 years after implant placement (0.14 mm, at each time intervals; Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMean radiographic peri-implant marginal bone levels and differences between groups and time periods up to 5 years after implant placement.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e1 month\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e3 months\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e6 months\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e1 year\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e2 years\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e5 years\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePiezo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.49 (0.31) [0.36;0.61]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.78 (0.36) [0.64;0.93]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.98 (0.35) [0.84;1.13]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.06 (0.37) [0.91;1.22]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.25 (0.36) [1.11;1.40]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.26 (0.35) [1.11;1.40]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.23 (0.33) [1.09;1.37]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDrill\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.41 (0.22) [0.32;0.50]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.65 (0.36) [0.50;0.80]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.81 (0.34) [0.67;0.95]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.92 (0.39) [0.76;1.08]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.11 (0.38) [0.96;1.27]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.12 (0.37) [0.96;1.27]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.09 (0.35) [0.94;1.23]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDifference [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.08 [-0.21;0.06]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.13 [-0.28;0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.17 [-0.32;-0.02]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.14 [-0.27;-0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.14 [-0.28;-0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.14 [-0.28;-0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.14 [-0.28;-0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2577\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0725\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0266*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0359*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0455*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0459*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0459*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\"\u003e*Statistically significant difference between groups.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMean radiographic peri-implant marginal bone level changes between groups and time periods up to 5 years after implant placement.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026ndash; 1 month\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;3 months\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;6 months\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;1 year\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;2 years\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;5 years\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePiezo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.30 (0.07) [0.15;0.44]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.50 (0.08) [0.33;0.67]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.58 (0.07) [0.42;0.73]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.77 (0.08) [0.60;0.94]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.77 (0.08) [0.60;0.94]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.74 (0.08) [0.58;0.91]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDrill\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.24 (0.07) [0.11;0.38]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.40 (0.08) [0.24;0.56]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.51 (0.07) [0.35;0.66]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.70 (0.07) [0.55;0.86]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.71 (0.07) [0.56;0.86]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 0.68 (0.07) [0.53;0.82]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDifference* [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.09 [-0.22;0.04]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.16 (-0.31;-0.01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.10 [-0.21;0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.11 [-0.23;0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.11 [-0.23;0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.11 [-0.24;0.01]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP-value*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.178\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.045**\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.082\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.091\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.092\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.083\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\"\u003e*Two-level mixed effect with patient as random effect at 1, 3 and 6 months, 1, 2 and 5 years after implant placement with baseline (implant placement) as a covariate; **Statistically significant difference between groups. All changes from baseline (implant placement) statistically significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv class=\"BlockQuote\"\u003e\n \u003cp\u003eAt 5-year post-placement peri-implant bone loss was 0.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 mm at piezo sites and 0.68\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07 mm at drilled sites, the difference being not statistically significant (difference = -0.11 mm; 95% CI -0.24 to 0.01; P (paired t-test)\u0026thinsp;=\u0026thinsp;0.083; Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). Only at 3 months post-placement was noticed a statistically significant difference in favour of drilled sites (difference = -0.16 mm; 95% CI -0.31 to -0.01; P (paired t-test)\u0026thinsp;=\u0026thinsp;0.03; Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). Marginal bone loss from baseline was statistically significant in both groups (P (paired t-test)\u0026thinsp;\u0026lt;\u0026thinsp;0.05; Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\n \u003cp\u003eSoft tissue thickness did not result to be statistically significantly affecting marginal bone level changes (estimate\u0026thinsp;=\u0026thinsp;0.05; 95% CI -0.03; 0.12; P\u0026thinsp;=\u0026thinsp;0.239) over time in the mixed effect model adjusted for baseline ISQ values (Table \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMixed effect model for mean radiographic peri-implant marginal bone level changes between groups and time periods up to 5 years after implant placement with soft tissue thickness as baseline covariate.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTerm\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEstimate\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSE\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% Lower\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% Upper\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIntercept\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0030*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eISQ at implant placement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8454\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSoft tissue thickness\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2393\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTime point (1 month)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTime point (3 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1710\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTime point (6 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1112\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTime point (12 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTime point (24 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTime point (5 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSite preparation with piezo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;.0001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003eTwo-level mixed effect with patient as random effect with baseline ISQ values, soft tissue thickness as a covariates; and site preparation method and time points as factors; *Statistically significant estimate.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eResonance frequency analysis (RFA) values (Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e) and changes (Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). At implant insertion time (baseline), RFA values were 70.98\u0026thinsp;\u0026plusmn;\u0026thinsp;10.38 at piezo sites and 70.82\u0026thinsp;\u0026plusmn;\u0026thinsp;9.21 at drilled sites, the difference being not statistically significant (difference = -0.16; 95% CI -3.61 to 3.29; P (paired t-test)\u0026thinsp;=\u0026thinsp;0.9245; Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). At 6 months post-placement, RFA change was 3.94\u0026thinsp;\u0026plusmn;\u0026thinsp;2.11 at piezo sites and 3.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.06 at drilled sites, the difference being not statistically significant (difference = -0.35; 95% CI -1.95 to 1.25; P (paired t-test)\u0026thinsp;=\u0026thinsp;0.672; Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). RFA changes from baseline were not statistically significant in both groups (Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eThe average time needed to prepare the implant site was of 329.44\u0026thinsp;\u0026plusmn;\u0026thinsp;134.65 sec for the piezo group and 92.64\u0026thinsp;\u0026plusmn;\u0026thinsp;52.60 sec for the drill group, showing a statistically significant difference in favour of the conventional drilling procedure (difference = -236.8 sec; 95% CI -286.12 to -187.48; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001).\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMean RFA values between groups and time periods up to 6 months after implant placement.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e1 month\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e3 months\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e6 months\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SD) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePiezo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 70.98 (10.38) [66.69;75.27]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 69.05 (16.26) [62.33;75.75]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 73.96 (10.16) [69.76;78.16]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 74.82 (9.74) [70.90;78.94]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDrill\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 70.82 (9.21) [67.02;74.62]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 70.68 (13.48) [65.12;76.24]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 73.4 (12.87) [68.09;78.71]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 74.52 (12.61) [69.32;79.72]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDifference [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 -0.16 [-3.61;3.29]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 1.65[-1.30;4.58]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 -0.56 [-2.42;1.30]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25\u0026thinsp;\u0026minus;\u0026thinsp;0.4[-2.23;1.43]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9245\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2615\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.5397\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.6554\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMean RFA values changes between groups and time periods up to 6 months after implant placement.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026ndash; 1 month\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;3 months\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eImplant placement \u0026minus;\u0026thinsp;6 months\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN Mean (SE) [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePiezo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 -1.94 (2.77) [-7.67;3.79]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 2.98 (2.05) [-1.24;7.20]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 3.94 (2.11) [-0.41;8.29]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDrill\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 -0.14 (2.18) [-4.65;4.37]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 2.58 (2.05) [-1.66;6.82]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 3.7 (2.06) [-0.56;7.96]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDifference* [95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.71 [-1.15;4.56]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.51 (-2.10;1.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.35 [-1.95;1.25]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP-value*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.254\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.540\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.672\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\"\u003e*Two-level mixed effect with patient as random effect at 1, 3 and 6 months after implant placement with baseline (implant placement) as a covariate. All changes from baseline (implant placement) non-statistically significant.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThis trial was designed to evaluate whether it could be more advantageous to prepare implant sites with piezosurgery when compared to conventional drilling. Apart some statistically significant differences in peri-implant bone level/loss favouring drilling in the range of 0.14 to 0.17 mm observed at different timepoints, but not having a clinically significant impact, the only statistical difference having a clinical significance was the need of about 4 minutes more to finalise the implantation procedure using piezosurgery. Despite that some may not consider this difference as clinically relevant, we cannot see any advantage in prolonging of 4 minutes the surgical time requested to complete the implantation procedure at each implant site using piezosurgery, especially in case of placement of multiple implants.\u003c/p\u003e \u003cp\u003eOur findings are, generally speaking, in agreement with those of other RCTs testing similar hypotheses. No difference for implant success rates and peri-implant bone loss were observed in a large multicentre RCT of split-mouth design (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). No difference in implants stability measured with RFA was found in another split-mouth RCT(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). Also another more detailed split-mouth RCT find no significant differences in peri-implant bone loss with the exception of a bit more pain perceived after 2 and 7 days at drilled sites (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). A study, possibly randomized and of parallel group design, reported longer preparation time with piezosurgery but less postoperative pain at day 1 and 2 as well as less swelling at day one and no differences thereafter, and no differences in bone loss (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). A split-mouth RCT comparing conventional drilling versus conventional drilling plus piezosurgery (the last 2 tips), found the only statistically significant difference at 8 weeks post-implantation for stability assessed with RFA favouring conventional drilling plus piezosurgery and no difference in radiographic bone loss 1 year after loading (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). However, such a difference in stability may not have a clinical impact. Another similar trial found no difference as well (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) but significant longer preparation times using piezosurgery\u003c/p\u003e \u003cp\u003eOur findings are in disagreement with the findings from the group who invented piezosurgery(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), who presented a significantly higher loss in percentage of implant stability measured with RFA in favour of piezosurgery up to 56 days post-implantation, without evaluating other outcome measures, as well as with the findings of another group (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Another, possibly split-mouth, RCT reported higher implant stability values assessed with RFA favouring piezosurgery prepared sites, no differences in peri-implant bone loss and bone density, and an average of 2 minutes more needed when using piezosurgery (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAnother split-mouth RCT, compared piezosurgery versus rotary drills for placing zygomatic implants (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). Zygomatic implants, as the name suggests, are placed in zygomatic bone, that is harder than maxillary bone. While the post-surgical haematoma was larger at drilled sites, the preparation of 10% of the sites allocated to piezosurgery was unsuccessful, so drills had to be used instead. This suggests that a combined use of conventional drills and piezosurgery, when indicated, could be advantageous at least for the placement of zygomatic implants.\u003c/p\u003e \u003cp\u003eNo particular advantages were observed when using piezosurgery as an alternative to rotary drills to prepare implant sites, however in the proximity of the alveolar inferior nerve, piezosurgery might be an interesting alternative since potentially less damaging than conventional drilling, however this hypothesis should be tested in properly designed and conducted RCTs.\u003c/p\u003e \u003cp\u003eRegarding the secondary hypothesis tested in this study, i.e. to evaluate whether crestal mucosa thickness could have an effect on bone loss, we found no effect. Our findings are in agreement with the findings/conclusions of some studies(\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e), but disagreement with other similar studies (\u003cspan additionalcitationids=\"CR18 CR19 CR20 CR21\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). These differences may be partially explained by the a not impressive variation in mucosa thickness in our study ranging from 1.5 to 5 mm with only five sites having a thickness of 1.5 mm, by the long-term data of our study compared to the short-term data usually published, and by the methodological flaws/bias affecting the majority of studies published on this topic.\u003c/p\u003e \u003cp\u003eThe main limitations of the present trial were not having investigated the patients\u0026rsquo; post-implantation view/preference about the two different preparation techniques, and the strict inclusion criteria which may limit the generalisability of the results, for instance to smokers. Nevertheless, since both procedures were tested in real clinical conditions, results can be generalized with confidence to a wider population having similar characteristics.\u003c/p\u003e"},{"header":"CONCLUSIONS","content":"\u003cp\u003eNo clinically appreciable differences were noticed when placing implants with piezosurgery or rotary instruments, however piezosurgery required on average 4 minutes more than conventional drills. No effect of initial crestal soft tissue thickness was observed on peri-implant bone loss.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe\u0026nbsp;study\u0026nbsp;protocol\u0026nbsp;was approved by the University of Mainz Ethics Committee (Ethics Committee No.: 837.1 85.1 5 (9953)).\u0026nbsp;All patients signed a specifically informed consent\u0026nbsp;that was\u0026nbsp;approved by the ethical committee\u0026nbsp;in order\u0026nbsp;to participate in the present trial\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData can be available on direct request via email to the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAuthors stated explicitly that there are no conflicts of interest in connection with this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThommen\u0026nbsp;Medical (Grenchen, Switzerland), the manufacturer of the implants used in this investigation,\u0026nbsp;partially funded this trial and donated the implants, however data belonged to the authors and by no means the sponsor interfered with the conduct of the trial or the publication of its results. The study was supported by Department of Periodontology and Operative Dentistry of Johannes Gutenberg University of Mainz.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAA, KS and BA conceived the idea; AA performed all surgeries; VF collected the data; JB and ME analysed the data; and ME led the writing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors wish to express their gratitude to Prof. Dr. Brita Willershausen for her contribution in study design and Nelly Kary for enrolling the patients.\u003c/p\u003e\n\u003cp\u003eConflict of interest statement: and the authors have stated explicitly that there are no conflicts of interest in connection with this article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eStacchi C, Vercellotti T, Torelli L, Furlan F, Di Lenarda R. Changes in implant stability using different site preparation techniques: twist drills versus piezosurgery. A single-blinded, randomized, controlled clinical trial. Clinical Implant Dentistry and Related Research 2013;15:188-197.\u003c/li\u003e\n \u003cli\u003eCanullo L, Penarrocha D, Penarrocha M, Rocio AG, Penarrocha-Diago M. Piezoelectric vs. conventional drilling in implant site preparation: pilot controlled randomized clinical trial with crossover design. Clinical Oral Implants Research 2014;25:1336-1343.\u003c/li\u003e\n \u003cli\u003eVercellotti T, Nevins ML, Kim DM, Nevins M, Wada K, Schenk RK, et al. Osseous response following resective therapy with piezosurgery. International Journal of Periodontics and Restorative Dentistry 2005;25:543-549.\u003c/li\u003e\n \u003cli\u003eBengazi F, Lang NP, Canciani E, Vigano P, Velez JU, Botticelli D. Osseointegration of implants with dendrimers surface characteristics installed conventionally or with Piezosurgery(R). A comparative study in the dog. Clinal Oral Implants Research 2014;25:10-15.\u003c/li\u003e\n \u003cli\u003eSagheb K, Kumar VV, Azaripour A, Walter C, Al-Nawas B, Kammerer PW. Comparison of conventional twist drill protocol and piezosurgery for implant insertion: an ex vivo study on different bone types. Clinical Oral Implants Research 2017;28:207-213.\u003c/li\u003e\n \u003cli\u003eStacchi C, Lombardi T, Baldi D, Bugea C, Rapani A, Perinetti G, et al. Immediate loading of implant-supported single crowns after conventional and ultrasonic implant site preparation: A multicenter randomized controlled clinical trial. BioMed research international 2018;2018:6817154.\u003c/li\u003e\n \u003cli\u003eSoheilifar S, Bidgoli M, Houshyar E, Farhadian M, Ghamari A. Comparing the effect of preparation of the implant sites with piezosurgery and conventional drilling on the stability of implants at 5-months follow-up. Journal of long-term effects of medical implants 2018;28:1-8.\u003c/li\u003e\n \u003cli\u003ePeker Tekdal G, Bostanci N, Belibasakis GN, Gurkan A. The effect of piezoelectric surgery implant osteotomy on radiological and molecular parameters of peri-implant crestal bone loss: a randomized, controlled, split-mouth trial. Clinical Oral Implants Research 2016;27:535-544.\u003c/li\u003e\n \u003cli\u003eScarano A, Carinci F, Lorusso F, Festa F, Bevilacqua L, Santos de Oliveira P, et al. Ultrasonic vs Drill Implant Site Preparation: Post-Operative Pain Measurement Through VAS, Swelling and Crestal Bone Remodeling: A Randomized Clinical Study. Materials 2018;11.\u003c/li\u003e\n \u003cli\u003eAlattar AN, Bede SYH. Does mixed conventional/piezosurgery implant site preparation affect implant stability? The Journal of craniofacial surgery 2018;29:e472-e475.\u003c/li\u003e\n \u003cli\u003eda Silva Neto UT, Joly JC, Gehrke SA. Clinical analysis of the stability of dental implants after preparation of the site by conventional drilling or piezosurgery. The British journal of oral \u0026amp; maxillofacial surgery 2014;52:149-153.\u003c/li\u003e\n \u003cli\u003eSallam HM, Khalifa GA, Khalifa FA. Dynamics of implant site preparation affecting the quality of osseointegrated implants in the maxillary aesthetic zone. J Craniomaxillofacial Surg 2020;48:645-652.\u003c/li\u003e\n \u003cli\u003ePistilli R, Esposito M, Barausse C, Balercia A, Bonifazi L, Buti J, et al. Conventional drills versus piezoelectric surgery preparation for placement of four immediately loaded zygomatic oncology implants in edentulous maxillae: results from a 3-year within person randomised controlled trial. Clinical Trials in Dentistry 2020;2:5-17.\u003c/li\u003e\n \u003cli\u003eAkcali A, Trullenque-Eriksson A, Sun C, Petrie A, Nibali L, Donos N. What is the effect of soft tissue thickness on crestal bone loss around dental implants? A systematic review. Clinical Oral Implants Research 2017;28:1046-1053.\u003c/li\u003e\n \u003cli\u003eSpinato S, Stacchi C, Lombardi T, Bernardello F, Messina M, Dovigo S, et al. Influence of abutment height and vertical mucosal thickness on early marginal bone loss around implants: A randomised clinical trial with an 18-month post-loading clinical and radiographic evaluation. International Journal of Oral Implantology (Berl) 2020;13:279-290.\u003c/li\u003e\n \u003cli\u003eMunoz M, Busoms E, Vilarrasa J, Albertini M, Ruiz-Magaz V, Nart J. Bone-level changes around implants with 1- or 3-mm-high abutments and their relation to crestal mucosal thickness: A 1-year randomized clinical trial. Journal of Clinical Periodontology 2021;48:1302-1311.\u003c/li\u003e\n \u003cli\u003eLinkevicius T, Puisys A, Linkeviciene L, Peciuliene V, Schlee M. Crestal bone stability around implants with horizontally matching connection after soft tissue thickening: A prospective clinical trial. Clinical Implant Dentistry and Related Research 2015;17:497-508.\u003c/li\u003e\n \u003cli\u003ePuisys A, Linkevicius T. The influence of mucosal tissue thickening on crestal bone stability around bone-level implants. A prospective controlled clinical trial. Clinical Oral Implants Research 2015;26:123-129.\u003c/li\u003e\n \u003cli\u003eLinkevicius T, Puisys A, Steigmann M, Vindasiute E, Linkeviciene L. Influence of vertical soft tissue thickness on crestal bone changes around Implants with platform switching: A comparative clinical study. Clinical Implant Dentistry and Related Research 2015;17:1228-1236.\u003c/li\u003e\n \u003cli\u003eSuarez-Lopez Del Amo F, Lin GH, Monje A, Galindo-Moreno P, Wang HL. Influence of soft tissue thickness on peri-implant marginal bone loss: A systematic review and meta-analysis. Journal of Periodontology 2016;87:690-699.\u003c/li\u003e\n \u003cli\u003evan Eekeren P, van Elsas P, Tahmaseb A, Wismeijer D. The influence of initial mucosal thickness on crestal bone change in similar macrogeometrical implants: a prospective randomized clinical trial. Clinical Oral Implants Research 2017;28:214-218.\u003c/li\u003e\n \u003cli\u003eDi Gianfilippo R, Valente NA, Toti P, Wang HL, Barone A. Influence of implant mucosal thickness on early bone loss: a systematic review with meta-analysis. Journal of periodontal \u0026amp; implant science 2020;50:209-225.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"international-journal-of-implant-dentistry","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"IJID","sideBox":"Learn more about [International Journal of Implant Dentistry](https://journalimplantdent.springeropen.com/)","snPcode":"40729","submissionUrl":"https://submission.nature.com/new-submission/40729/3","title":"International Journal of Implant Dentistry","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"dental implants, implant site preparation, piezoelectric surgery, rotary drills","lastPublishedDoi":"10.21203/rs.3.rs-5278685/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5278685/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose: \u003c/strong\u003eTo evaluate whether there are clinical benefits by preparing dental implant sites using piezosurgery instead of conventional rotary drills in healed bone crests and if initial crestal soft tissue thickness could have an impact on marginal bone loss.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Twenty-five partially edentulous patients requiring two single implants in molar/premolar areas had each site randomly allocated to either piezosurgery or to conventional rotary drill preparation according to a split-mouth design. Definitive screw-retained metal-ceramic crowns were delivered after 6 months. All patients were followed to 5 years after placement. Outcome measures were: implant/crown failures, complications, peri-implant marginal bone level changes, resonance frequency analysis (RFA), and time required come complete site preparation, recorded, when possible, by blinded assessors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003eNo patients dropped-out and no implant failed. Five years after placement, there were no statistically significant differences for complications (only one complication in the piezo group: difference = 0.04; P = 1), for peri-implant bone loss (difference = -0.11 mm; 95% CI -0.24 to 0.01; P = 0.083), and for RFA changes (6 months) (difference = -0.35; 95% CI -1.95 to 1.25; P = 0.672 between groups. Significantly more time was needed to prepare implant sites with piezosurgery (difference = 236.8 sec; 95% CI -286.12 to -187.48; P \u0026lt;0.0001). Initial soft tissue thickness had no effect on peri-implant bone loss (estimate = 0.05; 95% CI -0.03; 0.12; P = 0.239).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e No clinically appreciable differences were noticed when placing implants using piezosurgery or conventional instrumentation with rotary drill, however, the preparation with rotary drills was on average 4 minutes faster. No effect of initial crestal soft tissue thickness was observed on peri-implant bone loss.\u003c/p\u003e","manuscriptTitle":"Dental implant site preparation with conventional rotary drill or piezosurgery: five-year after placement results from a within person randomised controlled trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-10-23 09:39:35","doi":"10.21203/rs.3.rs-5278685/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-11-05T12:50:41+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-10-25T14:51:48+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-10-23T17:15:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"307870558411313722418122741255332066020","date":"2024-10-18T14:48:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"176476092576445388574450062099082149848","date":"2024-10-18T11:29:43+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-10-18T10:54:50+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-10-18T10:51:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-10-17T11:41:54+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Journal of Implant Dentistry","date":"2024-10-17T00:09:31+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"international-journal-of-implant-dentistry","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"IJID","sideBox":"Learn more about [International Journal of Implant Dentistry](https://journalimplantdent.springeropen.com/)","snPcode":"40729","submissionUrl":"https://submission.nature.com/new-submission/40729/3","title":"International Journal of Implant Dentistry","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9ad6fb32-1422-4faf-bda2-af2f29cf5747","owner":[],"postedDate":"October 23rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-12-11T06:38:48+00:00","versionOfRecord":[],"versionCreatedAt":"2024-10-23 09:39:35","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5278685","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5278685","identity":"rs-5278685","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}