3D Analysis of the condyle, glenoid fossa and mandible after maxillary protraction anchored in mini implants

• Autor(a) principal: Muniz, Luciana Trevisan Bittencourt
• Data de Publicação: 2022
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: https://www.teses.usp.br/teses/disponiveis/25/25144/tde-18112022-100525/
• topic: Angle Class III; Classe III de Angle; Expansão palatina; Interceptive; Malocclusion; Maloclusão; Orthodontics; Ortodontia Interceptativa; Palatal expansion technique

Introduction: This study aimed to evaluate the three-dimensional condyle, glenoid fossa and mandibular changes after miniscrew-anchored maxillary protraction (MAMP) therapy. Methods: The sample comprise 16 patients (7 female; 9 male) with Class III malocclusion and a mean initial age of 10.6 years (SD 1.00). The patients were treated with a mini-implant-supported maxillary protraction therapy using the Hybrid Hyrax appliance and two mandibular miniscrews distally to the permanent canines. Class III elastics were used connecting the maxillary molar hooks to the mandibular mini implants. Three-dimensional analysis was performed using the skull base superimposition of the before and after CBCT. The Paired t and One sample t-tests were used for the interphase comparison. A significance level of 5% was regarded for all tests. Results: No intragroup statistical difference was found in the three spatial planes after treatment for glenoid fossa and condyle. An increase in mandibular plane angulation and gonial angle was observed after treatment with MAMP therapy. The mandibular incisors showed a slight labial tip after treatment. Regarding the mandibular landmarks displacements, only the Gnathion showed a backward and downward change with treatment. Conclusion: The right and left condylion, right and left anterior fossa, right and left articular eminence showed similar and slight displacements in all planes of space after MAMP therapy. Slight changes were observed in the mandible after treatment with MAMP therapy. A clockwise rotation of the mandibular plane was observed. A slight posterior and inferior displacement of the anterior region of mandibular symphysis was observed after MAMP.