3D Printed Ventilation Tubes and their Effect on Biological Models

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Ventilation tubes are key in treatment. 3D printing improves prostheses in otorhinolaryngology, offering precision and greater adaptability. Material and Methods: An experimental study was conducted with Wistar rats from July to December 2020. 3D tympanostomy tube models were designed, with technical specifications and tests performed on inexpensive 3D printers. And the tympanostomy tube was inserted endoscopically. Results: Procedures were performed on five rats with implants in both ears. Pre-intervention pathologies, such as atical retraction and glue ear, were found. The PLA-printed tympanostomy tube showed improvement after adjustments. Histopathological results revealed significant middle and inner ear damage. Conclusion: In our study, the design and 3D printing of implants fulfilled the desired functions when modified, with a height of 5 mm. Complications included PLA degradation and ear damage. There were no adverse events during observation, highlighting the need for further research on 3D printed implants. Implants 3D Printing Ventilation Tubes Acute Otitis Media Figures Figure 1 Figure 2 Introduction Acute otitis media (AOM) is a disease characterized by the presence of fluid in the middle ear, accompanied by the sudden appearance of signs and symptoms of inflammation in this area. The presence of fluid in the middle ear can cause significant discomfort and affect hearing with hearing loss of 25 to 30 dB [1,2] . Treatment for acute otitis media includes pain management, observation, or antibiotics. Tympanostomy tubes are considered for children experiencing three or more episodes within six months or four episodes within a year, with at least one episode in the preceding six months [3] . The placement of the tubes, a key treatment for otitis media, addresses hearing impairment and damage to the tympanic membrane, and is the intervention of choice [ 4] . Three materials (fluoroplastic, silicone elastomer, or metal) are utilized alongside two fundamental designs, short-term and longer-term, in the majority of tympanostomy tubes [5] . In 1986, 3D printing debuted as additive manufacturing, revolutionizing production with rapid prototyping and innovative three-dimensional technology [ 6] . 3D model printing allows a system to create 3D objects with information from digital databases [ 7] . 3D printed models can mimic all the shapes needed in real patient anatomies, serving to improve patient care and surgical outcomes [ 8] . 3D printing in medicine has mainly focused on non-biological static structures, such as structural or space-filling prostheses [ 9] . In the area of otorhinolaryngology the use of prosthesis or implants is frequent, of these, tympanostomy tubes are the most commonly used, and with greater innovation. These have been updated with a retractable blade as a safety element, as well as the incorporation of a "back stop" proximal to the tip of the device to minimize the risk of unintentional over-insertion; during their innovation, 3D printed prototype devices were obtained for greater accessibility [ 10,11] . Within the advantages that the use of this technology offers the opportunity of 3D printed medical devices in small sizes to suit the wide range of needs of the pediatric population; as well as that the greater precision of 3D printed surgical guides has been proven to reduce complications and intervention time [1 2,13] . Material and Methods Experimental study, carried out from July 2020 to December 2020 in Wistar strain rats from the laboratory of breeding and reproduction of animals for experimentation of the university center of health sciences (biotherium). Population. Apparently healthy Wistar strain rats were included, excluding all previously tested rats with tympanic perforations prior to tympanostomy tube placement, with external ear and/or middle ear malformations. Phases. It was divided into two phases; in the first phase, ventilation tube models were designed for 3D printing. In the second phase, an experimental study was carried out with animals from the laboratory of breeding and reproduction of animals for experimentation. The digital design of the tympanostomy tube was made taking into account the following characteristics: internal diameter 1.1 mm, external diameter 2.2 mm, length 1.8 mm. At its upper end the tube has a 0.4 mm flange that protrudes from the cylinder, at the lower end the flange protrudes from the cylinder by 0.2 mm. In this way its design will be similar to the Shepherd tubes. The tube was packed in surgical paper and sent to steam sterilization according to the conventional technique. Implant. Solid Works 2018 software was used to design the 3D part, and for the transfer to the printer, Ultimaker cura 4.1 and cura 14.01 software was used to generate the G-codes. Tests were performed with both softwares. The models were printed on fused deposition model printers of the ANET A8, Ender 3 and TARANTULA I3 models, which are home-made 3D printers of the economic range. A resolution quality of 0.05 mm was used for 100% density. The printed model was not very stable and with low stiffness, making it easily collapsible. New tests were carried out with the 0.2 mm and 0.4 mm extruder tip, with which a stable and firm model was achieved, with an adequate stiffness when growing it at 278%, leaving it with a height of 5 mm. ( Figure 1) Surgical Procedure. ● The specimens were identified by means of an adhesive bracelet with the numbers 1,2,3,4 and 5. ● Prior to anesthesia, the rats were weighed to calculate the anesthetic dose. ● Anesthesia and analgesia with ketamine 70 mg/kg b.w. and xylazine 15 mg/kg b.w. infiltrated intraperitoneally. ● EOA was performed with the TITAN equipment of interacoustic using the DPOAES440 6Hz module (500-8k Hz maximum 30 Db). It was considered positive when there was a replica at the scanned frequency (check mark) and negative when no replica was obtained (cross mark). ● Endoscopic exploration of the tympanic membrane with Storz 1.7 mm endoscopic lens. ● The PLA tympanostomy tube was inserted under endoscopic vision after myringotomy in the posteroinferior quadrant, leaving a portion protruding into the external auditory canal. ● Since it was only possible to insert PLA tympanostomy tubes in 5 ears out of the 10 possible ears, we divided the ears into two groups: 1) With PLA insertion and 2) Without PLA insertion. ● Three months later, after anesthesia and analgesia with ketamine 70 mg/kg body weight and xylazine 15 mg/kg body weight infiltrated intraperitoneally, endoscopic exploration of the ears was performed to verify the permanence of the PLA tympanostomy tube or its absorption. ● EOA are taken again with the TITAN equipment of interacoustic by means of the DPOAES440 6Hz module (500-8k Hz maximum 30 Db). ● Subsequently, a lethal dose of sodium pentobarbital (90-120 mg/kg) is administered by intraperitoneal injection to each mouse for sacrifice of the experimental specimens. Statistical Analysis. A database was used with the use of Excel Software and Statistical Package for Social Sciences (SPSS), version 20 for Windows, a database was created and processed. The results were presented with descriptive statistics analysis. Statistical inference tests were performed in order to contrast the specific objectives by means of Fisher's Chi-Square or Exact Chi-Square test and Student's T-test. Ethical considerations. All procedures were carried out in accordance with the institutional guidelines of the laboratory for breeding and reproduction of animals for experimentation of the Centro Universitario de Ciencias de la Salud of the University of Guadalajara, which are in accordance with those approved by the Federal Law of Animal Health, NOM-062-ZOO-1999 and NOM-033-ZOO-1995. Results Five rats were included, all females, where implants were placed in both right and left ears for a total of 5 ears, in the rest the procedure could not be performed because an adhesive tympanic membrane was found during the exploration, this group was taken as control. ( Figure 2) Of the five in which the intervention was achieved, two ears were found with normal tympanic membrane and three ears with atical retraction, corresponding to specimens 2 bilateral, 1 bilateral and 3 right respectively. General characteristics of experimental ears: A prevalence of pre-intervention middle ear pathology was found in 80% of the specimens, of the atical retraction and adhesive otitis type in 30% and 50% respectively. The remaining 20% were clinically unaltered. Preintervention DPOAEs were performed and were found to be present in 100% of Group 1 and 0% of Group 2 (Table 1). Ears with absent emissions corresponded to ears with adhesive tympanic membranes. At post-intervention assessment, otoacoustic emissions were absent in all the ears examined (100%). Table 1. Pre and Postoperative Otoacoustic Emissions. Study specimen Pre-operative Post-operative Number Ear Group PLA Insertion Otoacoustic Emissions Otoacoustic Emissions 1 R 1 Yes Present Absent 1 L 1 Yes Present Absent 2 R 1 Yes Present Absent 2 L 1 Yes Present Absent 3 R 1 Yes Present Absent 3 L 2 No Absent Absent 4 R 2 No Absent Absent 4 L 2 No Absent Absent 5 R 2 No Absent Absent 5 L 2 No Absent Absent R: right; L: left Tympanostomy tube biodegradation time, tympanic membrane repair and associated complications: At the first evaluation, at 3 months, remnants of PLA were observed in one ear, in the rest there was no evidence of PLA with completely repaired TM. During the observation period, there were no adverse events such as otorrhea, otorrhagia, granulomas or other lesions, and all specimens survived. Histopathological results Middle Ear: We observed minimal to mild damage to the epithelial layer of the tympanic membrane, as well as inflammatory damage in the middle ear in 80% of Group 1, in contrast to 0% in Group 2. Inner ear: 100% of the specimens of Group 1 presented damage in the inner ear, ranging from minimal to moderate, including: epithelial damage of the organ of Corti; lesion of the lamina propria and/or the bony labyrinth; edema, hemorrhage, inflammation and fibrosis. When comparing Group 1 ears against Group 2 ears we found the difference in findings to be statistically significant with a p= 0.002. Table 2. Evaluation of the tympanic membrane, tube biodegradation and complications. Study specimen Pre-operative Post-operative Number Ear Group PLA Insertion Tympanic Membrane Tube Degradation at 3 Months Tympanic Membrane Repair Tympanic Membrane 1 R 1 Yes Retraction Sí Complete Adhesive 1 L 1 Yes Retraction Sí Complete Adhesive 2 R 1 Yes Normal Sí Complete Normal 2 L 1 Yes Normal Sí Complete Adhesive 3 R 1 Yes Retraction Sí Complete Adhesive 3 L 2 No Adhesive N/A N/A Adhesive 4 R 2 No Adhesive N/A N/A Adhesive 4 L 2 No Adhesive N/A N/A Adhesive 5 R 2 No Adhesive N/A N/A Adhesive 5 L 2 No Adhesive N/A N/A Adhesive R: right; L: left; N/A: not applicable Discussion 3D models are now being used as implants, opening up new options that are more patient-specific and cost-effective. This opens up a huge range of possibilities for 3D technology in the medical field [1 4,15] . Although in Otolaryngology there is a tendency to experiment with printing with biological materials, in our study we decided to experiment with the design and 3D printing of implants that can be easily manufactured at a lower cost, with biocompatible materials, easily accessible, with the aim that these same designs can in the future be shared by the medical community. We agree with Mcmillan et al. that although the literature reports successes in the fabrication of cartilage and bone structures for head and neck applications, the full potential of this technology has yet to be realized [1 6] . Thinking for the first time that there is not yet a practical solution having similarities to what was presented by Zhang et al. where they designed a new artificial airway device, based on many years of research experience in respiratory support therapy [1 7] . In our study we used an implant that at first was not stable and had low rigidity, making it collapsible, but when modified it managed to fulfill the desired functions. However, they are not as simple to perform as one would believe as well as Omari et al. tell us where the process of 3D printing patient-specific models is complex and includes several steps: preprocessing (e.g., capturing and editing image data for printing), processing, and postprocessing (removal of excess impression material, sterilization, etc.) [1 8] . In addition, the choice of the most appropriate printing technology and materials also substantially affects the manufacturing steps [1 9] . In an experimental study by Ensari et al. they applied a polylactic acid (PLA) film to the middle ear of guinea pigs. They found that it produced no detrimental effects on hearing or middle ear mucosa compared to the non-intervened side [ 20] . However, the lack of measurement of DPOAES in their study was a limitation in knowing the effects of PLA on the inner ear. In our experiment we observed an association between PLA degradation and mild middle ear and moderate inner ear damage at different histological levels (RR 5, 95% CI 0.866-28,861 p= 0.010), impacting the production of DPOAEs. Therefore, the association between PLA and histological damage of the inner ear is confirmed by not observing histological damage in the non-intervened ears, although we do not know if the damage is transient due to the short follow-up. Regarding the creation of such a small model, we observed that traditional PLA 3D printers have difficulty in reproducing models smaller than 5 mm. Therefore, we propose that another type of material and 3D printer could be used for this type of implant. In this regard, Hirsch et al. reproduced an ossicular chain implant adapted to the anatomical circumstances of the defect [ 20] . In a cadaveric model they carried out the replacement of the incus (3x2 mm) with a 3D printed model, using a resin printer (precision of 25 μm), commonly used for dental stereolithographic models. However, being a cadaveric model, it was not possible to know the effects of the resin on the inner ear. In our study we found the following post-implant changes in the middle ear: minimal to mild damage was observed in the epithelial layer of the tympanic membrane, as well as inflammatory damage in the middle ear in 80% of Group 1, in contrast to 0% of Group 2 in the inner ear: 100% of Group 1 specimens, presented damage in the inner ear, which ranged from minimal to moderate, among these: epithelial damage of the organ of Corti; lesion of the lamina propria and/or bony labyrinth; edema, hemorrhage, inflammation and fibrosis. Costa observed the temporal findings of 21 users where a chronic inflammatory process in the electrodes caused fibrosis and new bone formation; the inflammatory response was less intense around the electrodes closer to the most apical region of the cochlea [ 21] . Complications associated in our study at the first evaluation, at 3 months, remnants of PLA were observed in one ear, in the rest there was no evidence of PLA with completely repaired TM. During the observation period, no adverse events such as otorrhea, otorrhagia, granulomas or other lesions occurred, with all specimens surviving. These are not the only changes that can occur, since complications due to surgery at the time of implantation must also be considered. Lau presented the following complications of surgery in his study, which included blockage of the drainage with acute otitis media that required reoperation within six months in 3/54 children who had the drainage placed [2 2] . A prevalence of pre-intervention middle ear pathology was found in 80% of the specimens, of the atical retraction and glue ear type in 30% and 50% respectively. The remaining 20% were clinically unaltered. Preintervention DPOAEs were performed and found to be present in 100% of Group 1 and 0% of Group 2. Ears with absent emissions correspond to ears with adhesive tympanic membranes. At the postoperative evaluation, otoacoustic emissions were absent in all the ears explored (100%). We recognize as limitations of our study the small sample of specimens, as well as the high prevalence of pre-existing middle ear pathology, which prevented us from knowing the cochlear health of our control group. Although our results cannot be conclusive, we consider it important to continue experimenting with 3D printing for implants by modifying variables such as biopolymer, quality and resolution of the 3D printer, in order to improve the design and safety of the implant, while identifying materials that are well tolerated at the otologic level. Conclusion In our study, the design and 3D printing of implants achieved the desired functions. Among the complications, an association was found between PLA degradation and mild damage in the middle ear and moderate damage in the inner ear. In the evaluation corresponding to the observation period, there were no adverse events related to the implantation of the 3D model and all specimens were found to be surviving. According to our results, since it showed small short-term improvements, we consider that it is necessary to deepen the research related to 3D printed models. They offer the benefit of greater accessibility, as well as the possibility of implant customization according to the anatomical characteristics of the patient. Declarations Conflicts of interest. The authors declare that they have no conflicts of interest. Funding. Not applicable in this study. Data Availability Statement. The data that support the findings of this study are available upon reasonable request from the corresponding author. Author Contribution S.A.C.C. : design of the work, analysis, wrote the main manuscript textI.Y.C.L. : design of the work, wrote the main manuscript textL.H.G.C. : design of the work, A.G.O. : analysis, interpretation of dataG.C.G. : analysisE.C.P. : analysisS.R.O. : analysisS.J.V.S. : design of the work, analysis, interpretation of data, wrote the main manuscript textG.D.H. : design of the work, analysis, wrote the main manuscript textJ.A.T.O. : interpretation of dataS. E. G. M. : interpretation of dataC. F. 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Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 16 May, 2024 Reviews received at journal 16 May, 2024 Reviews received at journal 11 May, 2024 Reviewers agreed at journal 02 May, 2024 Reviewers agreed at journal 02 May, 2024 Reviewers agreed at journal 25 Mar, 2024 Reviewers invited by journal 25 Mar, 2024 Submission checks completed at journal 21 Mar, 2024 Editor assigned by journal 21 Mar, 2024 First submitted to journal 20 Mar, 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. We do this by developing innovative software and high quality services for the global research community. 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Occidente","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Gonzalo","middleName":"","lastName":"Delgado-Hernández","suffix":""},{"id":283731816,"identity":"1f3052a5-5e89-46b6-9f12-8a71dae18532","order_by":10,"name":"Jaime Alberto Tavares-Ortega","email":"","orcid":"","institution":"Hospital de Especialidades, Centro Médico Nacional de Occidente","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jaime","middleName":"Alberto","lastName":"Tavares-Ortega","suffix":""}],"badges":[],"createdAt":"2024-03-20 17:14:53","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4138741/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4138741/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":53449884,"identity":"dd8bdb4b-751f-453c-8c5c-29835e5fbfcc","added_by":"auto","created_at":"2024-03-26 06:26:21","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":210181,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePLA tympanostomy tube with a height of 5 mm.\u003c/em\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4138741/v1/48837f65e9f98f5b4a693306.png"},{"id":53449885,"identity":"68845bc4-99d6-4374-974e-fbaa453e8369","added_by":"auto","created_at":"2024-03-26 06:26:21","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":217017,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eTympanostomy Tube Placed in Biological Model\u003c/em\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4138741/v1/e8d38bff166fc635acabf18f.png"},{"id":53450554,"identity":"efaae465-bbfd-4151-94e3-2cb2ad03737e","added_by":"auto","created_at":"2024-03-26 06:34:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":671811,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4138741/v1/9f5ec72b-f1d2-442f-a853-954c2fed33d0.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"3D Printed Ventilation Tubes and their Effect on Biological Models","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAcute otitis media (AOM) is a disease characterized by the presence of fluid in the \u0026nbsp;middle ear, accompanied by the sudden appearance of signs and symptoms of \u0026nbsp;inflammation in this area. The presence of fluid in the middle ear can cause significant discomfort and affect hearing with hearing loss of 25 to 30 dB\u0026nbsp;\u003csup\u003e[1,2]\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTreatment for acute otitis media includes pain management, observation, or antibiotics. Tympanostomy tubes are considered for children experiencing three or more episodes within six months or four episodes within a year, with at least one episode in the preceding six months\u0026nbsp;\u003csup\u003e[3]\u003c/sup\u003e. The placement of\u0026nbsp;the\u0026nbsp;tubes,\u0026nbsp;a\u0026nbsp;key treatment for otitis media, addresses hearing impairment and damage to the tympanic membrane, and is the intervention of \u0026nbsp; choice\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e4]\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThree materials (fluoroplastic, silicone elastomer, or metal) are utilized alongside two fundamental designs, short-term and longer-term, in the majority of tympanostomy tubes\u0026nbsp;\u003csup\u003e[5]\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eIn 1986, 3D printing debuted as additive manufacturing, revolutionizing production with \u0026nbsp;rapid prototyping and innovative three-dimensional technology\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e6]\u003c/sup\u003e. 3D model printing \u0026nbsp;allows a system to create 3D objects with information from digital databases\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e7]\u003c/sup\u003e. 3D printed models can mimic all the shapes needed in real patient anatomies, serving \u0026nbsp; to improve patient care and surgical outcomes\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e8]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3D printing in medicine has mainly focused on non-biological static structures, such \u0026nbsp;as structural or space-filling prostheses\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e9]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn the area of otorhinolaryngology the use of prosthesis or implants is frequent, of \u0026nbsp;these, tympanostomy tubes are the most commonly used, and with greater innovation. \u0026nbsp;These have been updated with a retractable blade as a safety element, as well as the \u0026nbsp;incorporation of a \u0026quot;back stop\u0026quot; proximal to the tip of the device to minimize the risk of \u0026nbsp;unintentional over-insertion; during their innovation, 3D printed prototype devices were \u0026nbsp; obtained for greater accessibility\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e10,11]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWithin the advantages that the use of this technology offers the opportunity of 3D \u0026nbsp;printed medical devices in small sizes to suit the wide range of needs of the pediatric \u0026nbsp;population; as well as that the greater precision of 3D printed surgical guides has been \u0026nbsp;proven to reduce complications and intervention time\u0026nbsp;\u003csup\u003e[1\u003c/sup\u003e\u003csup\u003e2,13]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e"},{"header":"Material and Methods ","content":"\u003cp\u003eExperimental study, carried out from July 2020 to December 2020 in Wistar strain rats from the laboratory of breeding and reproduction of animals for experimentation of the \u0026nbsp; university center of health sciences (biotherium). \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ePopulation.\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eApparently healthy Wistar strain rats were included, excluding all previously tested \u0026nbsp;rats with tympanic perforations prior to tympanostomy tube placement, with external \u0026nbsp;ear and/or middle ear malformations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ePhases.\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIt was divided into two phases; in the first phase, ventilation tube models were \u0026nbsp;designed for 3D printing. In the second phase, an experimental study was carried out \u0026nbsp;with animals from the laboratory of breeding and reproduction of animals for \u0026nbsp; experimentation.\u003c/p\u003e\n\u003cp\u003eThe digital design of the tympanostomy tube was made taking into account the \u0026nbsp;following characteristics: internal diameter 1.1 mm, external diameter 2.2 mm, length \u0026nbsp;1.8 mm. At its upper end the tube has a 0.4 mm flange that protrudes from the cylinder, \u0026nbsp;at the lower end the flange protrudes from the cylinder by 0.2 mm. In this way its design will be similar to the Shepherd tubes. The tube was packed in surgical paper and sent to steam sterilization according to the conventional technique. \u0026nbsp;\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eImplant.\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSolid Works 2018 software was used to design the 3D part, and for the transfer to the \u0026nbsp;printer, Ultimaker cura 4.1 and cura 14.01 software was used to generate the G-codes. \u0026nbsp;Tests were performed with both softwares. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe models were printed on fused deposition model printers of the ANET A8, Ender 3 \u0026nbsp;and TARANTULA I3 models, which are home-made 3D printers of the economic \u0026nbsp;range. A resolution quality of 0.05 mm was used for 100% density. \u0026nbsp;The printed model was not very stable and with low stiffness, making it easily \u0026nbsp; collapsible. New tests were carried out with the 0.2 mm and 0.4 mm extruder tip, with \u0026nbsp;which a stable and firm model was achieved, with an adequate stiffness when growing \u0026nbsp;it at 278%, leaving it with a height of 5 mm.\u003cem\u003e\u0026nbsp;(\u003c/em\u003e\u003cem\u003eFigure 1)\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSurgical Procedure.\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e● The specimens were identified by means of an adhesive bracelet with the \u0026nbsp;numbers 1,2,3,4 and 5. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Prior to anesthesia, the rats were weighed to calculate the anesthetic dose. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Anesthesia and analgesia with ketamine 70 mg/kg b.w. and xylazine 15 mg/kg \u0026nbsp;b.w. infiltrated intraperitoneally.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● EOA was performed with the TITAN equipment of interacoustic using the \u0026nbsp;DPOAES440 6Hz module (500-8k Hz maximum 30 Db). It was considered \u0026nbsp; positive when there was a replica at the scanned frequency (check mark) and \u0026nbsp;negative when no replica was obtained (cross mark).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Endoscopic exploration of the tympanic membrane with Storz 1.7 mm \u0026nbsp;endoscopic lens.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● The PLA tympanostomy tube was inserted under endoscopic vision after \u0026nbsp;myringotomy in the posteroinferior quadrant, leaving a portion protruding into \u0026nbsp;the external auditory canal.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Since it was only possible to insert PLA tympanostomy tubes in 5 ears out of \u0026nbsp;the 10 possible ears, we divided the ears into two groups: 1) With PLA \u0026nbsp;insertion and 2) Without PLA insertion. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Three months later, after anesthesia and analgesia with ketamine 70 mg/kg \u0026nbsp;body weight and xylazine 15 mg/kg body weight infiltrated intraperitoneally, \u0026nbsp;endoscopic exploration of the ears was performed to verify the permanence of \u0026nbsp;the PLA tympanostomy tube or its absorption. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● EOA are taken again with the TITAN equipment of interacoustic by means of \u0026nbsp;the DPOAES440 6Hz module (500-8k Hz maximum 30 Db). \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e● Subsequently, a lethal dose of sodium pentobarbital (90-120 mg/kg) is \u0026nbsp;administered by intraperitoneal injection to each mouse for sacrifice of the \u0026nbsp;experimental specimens. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStatistical Analysis. \u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eA database was used with the use of Excel Software and Statistical Package for Social \u0026nbsp;Sciences (SPSS), version 20 for Windows, a database was created and processed. \u0026nbsp;The results were presented with descriptive statistics analysis. Statistical inference tests were performed in order to contrast the specific objectives by means \u0026nbsp;of Fisher\u0026apos;s Chi-Square or Exact Chi-Square test and Student\u0026apos;s T-test. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eEthical considerations.\u0026nbsp;\u003c/em\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAll procedures were carried out in accordance with the institutional guidelines of the \u0026nbsp; laboratory for breeding and reproduction of animals for experimentation of the Centro \u0026nbsp;Universitario de Ciencias de la Salud of the University of Guadalajara, which are in \u0026nbsp;accordance with those approved by the Federal Law of Animal Health, NOM-062-ZOO-1999 and NOM-033-ZOO-1995.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eFive rats were included, all females, where implants were placed in both right and left \u0026nbsp;ears for a total of 5 ears, in the rest the procedure could not be performed because an \u0026nbsp;adhesive tympanic membrane was found during the exploration, this group was taken \u0026nbsp;as control. \u003cem\u003e(\u003c/em\u003e\u003cem\u003eFigure\u0026nbsp;2)\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eOf the five in which the intervention was achieved, two ears were found with normal \u0026nbsp;tympanic membrane and three ears with atical retraction, corresponding to specimens \u0026nbsp;2 bilateral, 1 bilateral and 3 right respectively. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGeneral characteristics of experimental ears: \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA prevalence of pre-intervention middle ear pathology was found in 80% of the \u0026nbsp;specimens, of the atical retraction and adhesive otitis type in 30% and 50% \u0026nbsp;respectively. The remaining 20% were clinically unaltered. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePreintervention DPOAEs were performed and were found to be present in 100% of \u0026nbsp;Group 1 and 0% of Group 2 (Table 1). Ears with absent emissions corresponded to \u0026nbsp;ears with adhesive tympanic membranes. At post-intervention assessment, otoacoustic \u0026nbsp; emissions were absent in all the ears examined (100%). \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eTable 1. Pre and Postoperative Otoacoustic Emissions.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"550\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.54545454545455%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003eStudy specimen\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePre-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eNumber\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eEar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003ePLA Insertion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eOtoacoustic Emissions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eOtoacoustic Emissions\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.909090909090908%\" valign=\"top\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.818181818181817%\" valign=\"top\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003eR: right; L: left\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eTympanostomy tube biodegradation time, tympanic membrane repair and associated \u0026nbsp;complications: At the first evaluation, at 3 months, remnants of PLA were observed in \u0026nbsp;one ear, in the rest there was no evidence of PLA with completely repaired TM. During \u0026nbsp; the observation period, there were no adverse events such as otorrhea, otorrhagia, \u0026nbsp;granulomas or other lesions, and all specimens survived.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHistopathological results\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMiddle Ear: We observed minimal to mild damage to the epithelial layer of the tympanic \u0026nbsp;membrane, as well as inflammatory damage in the middle ear in 80% of Group 1, in \u0026nbsp;contrast to 0% in Group 2. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eInner ear: 100% of the specimens of Group 1 presented damage in the inner ear, \u0026nbsp;ranging from minimal to moderate, including: epithelial damage of the organ of Corti; \u0026nbsp;lesion of the lamina propria and/or the bony labyrinth; edema, hemorrhage, \u0026nbsp; inflammation and fibrosis. When comparing Group 1 ears against Group 2 ears we \u0026nbsp;found the difference in findings to be statistically significant with a p= 0.002. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eTable 2. Evaluation of the tympanic membrane, tube biodegradation and complications.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"601\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.10981697171381%\" colspan=\"3\"\u003e\n \u003cp\u003eStudy specimen\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003ePre-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"39.60066555740433%\" colspan=\"3\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003eNumber\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eEar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003ePLA Insertion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eTympanic Membrane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eTube Degradation at 3 Months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eTympanic Membrane Repair\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eTympanic Membrane\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eRetraction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eS\u0026iacute;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eComplete\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eRetraction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eS\u0026iacute;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eComplete\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eNormal\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eS\u0026iacute;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eComplete\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eNormal\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eNormal\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eS\u0026iacute;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eComplete\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eRetraction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eS\u0026iacute;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eComplete\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"11.647254575707155%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.149750415973378%\"\u003e\n \u003cp\u003eL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.482529118136439%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.477537437603994%\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.642262895174708%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.312811980033278%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.307820299500833%\"\u003e\n \u003cp\u003eN/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.980033277870216%\"\u003e\n \u003cp\u003eAdhesive\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003eR: right; L: left; N/A: not applicable\u003c/em\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003e3D models are now being used as implants, opening up new options that are more \u0026nbsp;patient-specific and cost-effective. This opens up a huge range of possibilities for 3D\u0026nbsp;\u003c/p\u003e\n\u003cp\u003etechnology in the medical field\u0026nbsp;\u003csup\u003e[1\u003c/sup\u003e\u003csup\u003e4,15]\u0026nbsp;\u003c/sup\u003e. Although in Otolaryngology there is a tendency \u0026nbsp;to experiment with printing with biological materials, in our study we decided to \u0026nbsp;experiment with the design and 3D printing of implants that can be easily manufactured \u0026nbsp; at a lower cost, with biocompatible materials, easily accessible, with the aim that these \u0026nbsp;same designs can in the future be shared by the medical community. We agree with \u0026nbsp;Mcmillan et al. that although the literature reports successes in the fabrication of cartilage and bone structures for head and neck applications, the full potential of this \u0026nbsp;technology has yet to be realized\u0026nbsp;\u003csup\u003e[1\u003c/sup\u003e\u003csup\u003e6]\u0026nbsp;\u003c/sup\u003e. Thinking for the first time that there is not yet a \u0026nbsp;practical solution having similarities\u0026nbsp;to\u0026nbsp;what was presented by Zhang et al. where they \u0026nbsp;designed a new artificial airway device, based on many years of research experience \u0026nbsp;in respiratory support therapy\u0026nbsp;\u003csup\u003e[1\u003c/sup\u003e\u003csup\u003e7]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn our study we used an implant that at first was not stable and had low rigidity, making it collapsible, but when modified it managed to fulfill the desired functions. However, \u0026nbsp; they are not as simple to perform as one would believe as well as Omari et al. tell us \u0026nbsp;where the process of 3D printing patient-specific models is complex and includes \u0026nbsp;several steps: preprocessing (e.g., capturing and editing image data for printing), \u0026nbsp; processing, and postprocessing (removal of excess impression material, sterilization,\u0026nbsp;etc.)\u0026nbsp;\u003csup\u003e[1\u003c/sup\u003e\u003csup\u003e8]\u003c/sup\u003e. In addition, the choice of the most appropriate printing technology and \u0026nbsp; materials also substantially affects the manufacturing steps\u0026nbsp;\u003csup\u003e[1\u003c/sup\u003e\u003csup\u003e9]\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eIn an experimental study by Ensari et al. they applied a polylactic acid (PLA) film to \u0026nbsp;the middle ear of guinea pigs. They found that it produced no detrimental effects on \u0026nbsp;hearing or middle ear mucosa compared to the non-intervened side\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e20]\u0026nbsp;\u003c/sup\u003e. However, the \u0026nbsp; lack of measurement of DPOAES in their study was a limitation in knowing the effects \u0026nbsp;of PLA on the inner ear. In our experiment we observed an association between PLA \u0026nbsp;degradation and mild middle ear and moderate inner ear damage at different \u0026nbsp;histological levels (RR 5, 95% CI 0.866-28,861 p= 0.010), impacting the production of \u0026nbsp;DPOAEs. Therefore, the association between PLA and histological damage of the \u0026nbsp;inner ear is confirmed by not observing histological damage in the non-intervened \u0026nbsp;ears, although we do not know if the damage is transient due to the short follow-up. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRegarding the creation of such a small model, we observed that traditional PLA 3D \u0026nbsp;printers have difficulty in reproducing models smaller than 5 mm. Therefore, we \u0026nbsp;propose that another type of material and 3D printer could be used for this type of \u0026nbsp; implant. In this regard, Hirsch et al. reproduced an ossicular chain implant adapted to \u0026nbsp;the anatomical circumstances of the defect\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e20]\u0026nbsp;\u003c/sup\u003e. In a cadaveric model they carried out\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ethe replacement of the incus (3x2 mm) with a 3D printed model, using a resin printer \u0026nbsp;(precision of 25 \u0026mu;m), commonly used for dental stereolithographic models. However, \u0026nbsp;being a cadaveric model, it was not possible to know the effects of the resin on the \u0026nbsp; inner ear. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn our study we found the following post-implant changes in the middle ear: minimal to \u0026nbsp;mild damage was observed in the epithelial layer of the tympanic membrane, as well \u0026nbsp;as inflammatory damage in the middle ear in 80% of Group 1, in contrast to 0% of \u0026nbsp; Group 2 in the inner ear: 100% of Group 1 specimens, presented damage in the inner \u0026nbsp;ear, which ranged from minimal to moderate, among these: epithelial damage of the \u0026nbsp;organ of Corti; lesion of the lamina propria and/or bony labyrinth; edema, hemorrhage, \u0026nbsp; inflammation and fibrosis. Costa observed the temporal findings of 21 users where a \u0026nbsp;chronic inflammatory process in the electrodes caused fibrosis and new bone \u0026nbsp;formation; the inflammatory response was less intense around the electrodes closer \u0026nbsp;to the most apical region of the cochlea\u0026nbsp;\u003csup\u003e[\u003c/sup\u003e\u003csup\u003e21]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eComplications associated in our study at the first evaluation, at 3 months, remnants of \u0026nbsp;PLA were observed in one ear, in the rest there was no evidence of PLA with \u0026nbsp;completely repaired TM. During the observation period, no adverse events such as \u0026nbsp; otorrhea, otorrhagia, granulomas or other lesions occurred, with all specimens \u0026nbsp;surviving. These are not the only changes that can occur, since complications due to \u0026nbsp;surgery at the time of implantation must also be considered. Lau presented the \u0026nbsp; following complications of surgery in his study, which included blockage of the \u0026nbsp;drainage with acute otitis media that required reoperation within six months in 3/54 \u0026nbsp;children who had the drainage placed\u0026nbsp;\u003csup\u003e[2\u003c/sup\u003e\u003csup\u003e2]\u0026nbsp;\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA prevalence of\u0026nbsp;pre-intervention\u0026nbsp;middle ear pathology was found in 80% of the \u0026nbsp;specimens, of the atical retraction and glue ear type in 30% and 50% respectively. The remaining 20% were clinically unaltered. Preintervention DPOAEs were performed \u0026nbsp;and found to be present in 100% of Group 1 and 0% of Group 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEars with absent emissions correspond to ears with adhesive tympanic\u0026nbsp;membranes. \u0026nbsp;At the postoperative evaluation, otoacoustic emissions were absent in all the ears \u0026nbsp;explored (100%).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe recognize as limitations of our study the small sample of specimens, as well as \u0026nbsp;the high prevalence of pre-existing middle ear pathology, which prevented us from \u0026nbsp;knowing the cochlear health of our control group. Although our results cannot be \u0026nbsp; conclusive, we consider it important to continue experimenting with 3D printing for\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eimplants by modifying variables such as biopolymer, quality and resolution of the 3D \u0026nbsp;printer, in order to improve the design and safety of the implant, while identifying \u0026nbsp;materials that are well tolerated at the otologic level. \u0026nbsp;\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn our study, the design and 3D printing of implants achieved the desired functions. Among the complications, an association was found between PLA degradation and mild damage in the middle ear and moderate damage in the inner ear. In the evaluation corresponding to the observation period, there were no adverse \u0026nbsp;events related to the implantation of the 3D model\u0026nbsp;and all specimens were found to be surviving.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAccording to our results, since it showed small short-term improvements, we consider that it is necessary to deepen the research related to 3D printed models. They offer the benefit of greater accessibility, as well as the possibility of implant customization according to the anatomical characteristics of the patient.\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003eConflicts of interest.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no conflicts of interest. \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFunding.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable in this study.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eData Availability Statement.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are available upon reasonable request from the corresponding author.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eS.A.C.C. : design of the work, analysis, wrote the main manuscript textI.Y.C.L. : design of the work, wrote the main manuscript textL.H.G.C. : design of the work, A.G.O. : analysis, interpretation of dataG.C.G. : analysisE.C.P. : analysisS.R.O. : analysisS.J.V.S. : design of the work, analysis, interpretation of data, wrote the main manuscript textG.D.H. : design of the work, analysis, wrote the main manuscript textJ.A.T.O. : interpretation of dataS. E. G. M. : interpretation of dataC. F. O. : design of the work, analysis, interpretation of dataAll authors reviewed the manuscript\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eVenekamp RP, Mick P, Schilder AG, Nunez DA. Grommets (ventilation tubes) for recurrent acute otitis media in children. Cochrane Database Syst Rev. 2018 May 9;5(5):CD012017. doi: 10.1002/14651858.CD012017.pub2. PMID: 29741289; PMCID: PMC6494623. \u003c/li\u003e\n\u003cli\u003eShaffer AD, Ford MD, Choi SS, Jabbour N. The Impact of Tympanostomy Tubes on Speech and Language Development in Children with Cleft Palate. Otolaryngol Head Neck Surg. 2017 Sep;157(3):504-514. doi: 10.1177/0194599817703926. Epub 2017 May 2. PMID: 28462671. \u003c/li\u003e\n\u003cli\u003eGaddey HL, Wright MT, Nelson TN. Otitis Media: Rapid Evidence Review. \u003cem\u003eAm Fam Physician\u003c/em\u003e. 2019;100(6):350-356.\u003c/li\u003e\n\u003cli\u003eVanneste P, Page C. Otitis media with effusion in children: pathophysiology, diagnosis, and treatment. A review. J Otol. 2019 Jun;14(2):33-39. doi: 10.1016/j.joto.2019.01.005. Epub 2019 Jan 31. PMID: 31223299; PMCID: PMC6570640. \u003c/li\u003e\n\u003cli\u003eIsaacson G. Tympanostomy Tubes-A Visual Guide for the Young Otolaryngologist. \u003cem\u003eEar Nose Throat J\u003c/em\u003e. 2020;99(1_suppl):8S-14S. doi:10.1177/0145561320929885\u003c/li\u003e\n\u003cli\u003eZhong N, Zhao X. 3D printing for clinical application in otorhinolaryngology. Eur Arch Otorhinolaryngol. 2017 Dec;274(12):4079-4089. doi: 10.1007/s00405- 017-4743-0. Epub 2017 Sep 19. PMID: 28929219.\u003c/li\u003e\n\u003cli\u003eZoccali F, Colizza A, Cialente F, Di Stadio A, La Mantia I, Hanna C, Minni A, Ralli M, Greco A, de Vincentiis M. 3D Printing in Otolaryngology Surgery: Descriptive Review of Literature to Define the State of the Art. Healthcare (Basel). 2022 Dec 29;11(1):108. doi: 10.3390/healthcare11010108. PMID: 36611568; PMCID: PMC9819565. \u003c/li\u003e\n\u003cli\u003eHong CJ, Giannopoulos AA, Hong BY, Witterick IJ, Irish JC, Lee J, Vescan A, Mitsouras D, Dang W, Campisi P, de Almeida JR, Monteiro E. Clinical applications of three-dimensional printing in otolaryngology-head and neck surgery: A systematic review. Laryngoscope. 2019 Sep;129(9):2045-2052. doi: 10.1002/lary.27831. Epub 2019 Jan 30. PMID: 30698840. \u003c/li\u003e\n\u003cli\u003eMurphy SV, De Coppi P, Atala A. Opportunities and challenges of translational 3D bioprinting. Nat Biomed Eng. 2020 Apr;4(4):370-380. doi: 10.1038/s41551- 019-0471-7. Epub 2019 Nov 6. PMID: 31695178. \u003c/li\u003e\n\u003cli\u003eLawrence R, McGowan P, Daniel M. An all-in-one tympanostomy tube insertion device: results of usability testing in fourteen cadaveric and twelve plastic model ears. Clin Otolaryngol. 2017 Jun;42(3):765-768. doi: 10.1111/coa.12689. Epub 2016 Jun 30. PMID: 27273159. \u003c/li\u003e\n\u003cli\u003eWhelan RL, Maguire RC. Tympanostomy Tube Innovation: Advances in Device Material, Design, and Office-Based Technology. Ear Nose Throat J. 2020 Nov;99(1_suppl):48S-50S. doi: 10.1177/0145561320924910. Epub 2020 Jun 2. PMID: 32484409. \u003c/li\u003e\n\u003cli\u003eAuthors; Jones S, Walter M. Shortages of Care and Medical Devices Affecting the Pediatric Patient Population: CADTH Horizon Scan [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2023 Aug. Report No.: EH0116. PMID: 37934838. \u003c/li\u003e\n\u003cli\u003eYou P, Bartellas M. Three-dimensional Printing in Pediatric Otolaryngology. Otolaryngol Clin North Am. 2022 Dec;55(6):1243-1251. doi: 10.1016/j.otc.2022.07.013. PMID: 36371138. \u003c/li\u003e\n\u003cli\u003eZhong N, Zhao X. 3D printing for clinical application in otorhinolaryngology. Eur Arch Oto-Rhino-Laryngology. 2017;274(12):4079-89. \u003c/li\u003e\n\u003cli\u003eCanzi P, Magnetto M, Marconi S, Morbini P, Mauramati S, Aprile F, et al. New frontiers and emerging applications of 3D printing in ENT surgery: A systematic review of the literature. Acta Otorhinolaryngol Ital. 2018;38(4):286-303. \u003c/li\u003e\n\u003cli\u003eMcMillan A, McMillan N, Gupta N, Kanotra SP, Salem AK. 3D Bioprinting in Otolaryngology: A Review. Adv Healthc Mater. 2023 Jul;12(19):e2203268. doi: 10.1002/adhm.202203268. Epub 2023 Mar 31. PMID: 36921327; PMCID: PMC10502192. \u003c/li\u003e\n\u003cli\u003eZhang J, Li H. [A new type of artificial airway sealer used between artificial airway and ventilator pipeline]. Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2023 Sep;35(9):991-994. Chinese. doi: 10.3760/cma.j.cn121430-20230310-00168. PMID: 37803961. \u003c/li\u003e\n\u003cli\u003eOmari A, Frend\u0026oslash; M, S\u0026oslash;rensen MS, Andersen SAW, Frithioff A. The cutting edge of customized surgery: 3D-printed models for patient-specific interventions in otology and auricular management-a systematic review. Eur Arch Otorhinolaryngol. 2022 Jul;279(7):3269-3288. doi: 10.1007/s00405-022- 07291-0. Epub 2022 Feb 15. PMID: 35166908. \u003c/li\u003e\n\u003cli\u003eEnsari N, Tutar H, Ekinci O, Ugur MB, Bayazıt YA, Gokdogan C, et al. Effects of polylactic acid film on middle ear mucosa and cochlear function in Guinea pigs. Eur Arch Oto-Rhino-Laryngology. 2015;272(5):1091-7. \u003c/li\u003e\n\u003cli\u003eHirsch JD, Vincent RL, Eisenman DJ. Surgical reconstruction of the ossicular chain with custom 3D printed ossicular prosthesis. 3D Print Med. 2017;3(1):4- 11. \u003c/li\u003e\n\u003cli\u003eCosta LBAD, Vicente LC, Silva LTDN, Alvarenga KF, Salgado MH, Costa OA, Brito R. Analysis of aided thresholds in children who have undergone cochlear reimplantation: a ten-year follow-up. Codas. 2023 Oct 30;35(6):e20210293. Portuguese, English. doi: 10.1590/2317-1782/2023202021293pt. PMID: 37909539. \u003c/li\u003e\n\u003cli\u003eLau L, Mick P, Nunez DA. WITHDRAWN: Grommets (ventilation tubes) for recurrent acute otitis media in children. Cochrane Database Syst Rev. 2018 Apr 6;4(4):CD004741. doi: 10.1002/14651858.CD004741.pub3. PMID: 29624209; PMCID: PMC6494442.\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":"3d-printing-in-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tdpm","sideBox":"Learn more about [3D Printing in Medicine](https://threedmedprint.biomedcentral.com/)","snPcode":"41205","submissionUrl":"https://submission.nature.com/new-submission/41205/3","title":"3D Printing in Medicine","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Implants, 3D Printing, Ventilation Tubes, Acute Otitis Media","lastPublishedDoi":"10.21203/rs.3.rs-4138741/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4138741/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eIntroduction: \u003c/strong\u003eAcute otitis media (AOM) causes inflammation and hearing loss. Ventilation tubes are key in treatment. 3D printing improves prostheses in otorhinolaryngology, offering precision and greater adaptability.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterial and Methods: \u003c/strong\u003eAn experimental study was conducted with Wistar rats from July to December 2020. 3D tympanostomy tube models were designed, with technical specifications and tests performed on inexpensive 3D printers. And the tympanostomy tube was inserted endoscopically. \u003cstrong\u003eResults: \u003c/strong\u003eProcedures were performed on five rats with implants in both ears. Pre-intervention pathologies, such as atical retraction and glue ear, were found. The PLA-printed tympanostomy tube showed improvement after adjustments. Histopathological results revealed significant middle and inner ear damage.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eIn our study, the design and 3D printing of implants fulfilled the desired functions when modified, with a height of 5 mm. Complications included PLA degradation and ear damage. There were no adverse events during observation, highlighting the need for further research on 3D printed implants.\u0026nbsp;\u003c/p\u003e","manuscriptTitle":"3D Printed Ventilation Tubes and their Effect on Biological Models","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-26 06:26:16","doi":"10.21203/rs.3.rs-4138741/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-05-16T22:05:24+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-05-16T22:02:16+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-05-11T13:24:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"279237181902820598193135583257078395335","date":"2024-05-02T18:50:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"314502394136963048628102858721750785830","date":"2024-05-02T11:50:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"0887ae04-3089-4956-a492-dae84d45aeaa","date":"2024-03-25T17:20:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-03-25T17:18:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-03-22T02:24:28+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-03-22T02:24:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"3D Printing in Medicine","date":"2024-03-20T17:13:40+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"3d-printing-in-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tdpm","sideBox":"Learn more about [3D Printing in Medicine](https://threedmedprint.biomedcentral.com/)","snPcode":"41205","submissionUrl":"https://submission.nature.com/new-submission/41205/3","title":"3D Printing in Medicine","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c7d50079-e450-433a-ab78-c20dfa15f602","owner":[],"postedDate":"March 26th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-06-20T20:38:12+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-26 06:26:16","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4138741","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4138741","identity":"rs-4138741","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}