Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-06-28T16:55:44Z No. of bitstreams: 1 JONATHAS_DANIEL_PAGGI_CLAUS_TES.pdf: 15775593 bytes, checksum: 5bac7d16a07d5e8df3ca1f344cccdfff (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-05T11:30:41Z (GMT) No. of bitstreams: 1 JONATHAS_DANIEL_PAGGI_CLAUS_TES.pdf: 15775593 bytes, checksum: 5bac7d16a07d5e8df3ca1f344cccdfff (MD5) / Made available in DSpace on 2018-07-05T11:41:25Z (GMT). No. of bitstreams: 1 JONATHAS_DANIEL_PAGGI_CLAUS_TES.pdf: 15775593 bytes, checksum: 5bac7d16a07d5e8df3ca1f344cccdfff (MD5) Previous issue date: 2018-03-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Purpose: The aim of the present study was to use cone-beam computed tomography (CBCT) regional superimposition to investigate the effect of bimaxillary advancement orthognathic surgery on condylar remodeling of the temporo mandibular joint (TMJ). Materials and Methods: Using a retrospective study design, 56 condyles from 28 healthy patients (age from 16 to 50 years) with mandibular retrognathism treated with bimaxillary advancement had CBCT scans taken pre-operatively and at an average 14 months postoperatively. Pre- and post-surgical scans were superimposed using regional and automated voxel-based registration to assess condylar changes in the follow-up period. The linear alterations were measured in six different areas of each condyle to assess the pattern of condylar remodeling. Results: Although no significant correlation was observed between changes in condylar surfaces, bone resorption occurred predominantly in the posterior and superior region, while bone formation was predominantly in the anterior surface. Medial and lateral surfaces presented fewer bone changes. The overall bone changes were smaller than 1mm in 48 condyles (85,7%) in 21 patients (75%). Conclusions: The results of this study suggest the hypothesis that alterations occurring in TMJ after performing orthognathic surgeries occur similar to an adaptive response, especially in healthy patients, other than a pathological or inflammatory process. Other studies with similar methodologies may clarify the mechanisms involved in cases where the process of condylar remodeling is more present. / Prop?sito: O objetivo do presente estudo foi utilizar a superposi??o regional de tomografia computadorizada do feixe c?nico (TCFC) para investigar o efeito da cirurgia ortogn?tica de avan?o bimaxilar no processo de remodela??o do c?ndilo da articula??o t?mporo mandibular (ATM). Materiais e m?todos: Usando um estudo do tipo retrospectivo, 56 c?ndilos de 28 pacientes saud?veis (idade de 16 a 50 anos) com retrognatismo mandibular tratados com cirurgia de avan?o bimaxilar tiveram exames de TCFC tomados no pr?-operat?rio e em uma m?dia de 14 meses no p?s-operat?rio. Foi utilizada superposi??o regional dos exames pr? e p?s-operat?rios com registro autom?tico por voxels para avaliar as altera??es condilares no per?odo de acompanhamento. As altera??es lineares foram mensuradas em seis diferentes ?reas de cada c?ndilo para avaliar o padr?o do processo de remodela??o condilar. Resultados: Embora n?o tenha sido observado correla??o significante das altera??es condilares entre cada superf?cie investigada, a reabsor??o ?ssea ocorreu mais predominantemente na regi?o superior e posterior, enquanto a aposi??o de osso neoformado foi mais predominante na superf?cie anterior. As superf?cies medial e lateral apresentaram as menores altera??es. As mudan?as no osso condilar em geral foram menores do que 1 mm em 48 c?ndilos (85,7%) em 21 pacientes (75%). Conclus?es: Os resultados deste estudo sugerem a hip?tese de que as altera??es ocorridas na ATM ap?s a realiza??o de cirurgias ortogn?ticas ocorrem com uma resposta adaptativa, especialmente em pacientes saud?veis, diferentes de um processo patol?gico/inflamat?rio. Outros estudos com metodologias semelhantes poder?o esclarecer quais os mecanismos envolvidos nos casos onde o processo de remodela??o condilar est? mais presente.