Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-03-19T17:16:06Z No. of bitstreams: 1 FERNANDO_DE_OLIVEIRA_ANDRIOLA_DIS.pdf: 1889802 bytes, checksum: 4fbb8e2e462022c1c29eeda8628a848b (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-04-03T16:47:33Z (GMT) No. of bitstreams: 1 FERNANDO_DE_OLIVEIRA_ANDRIOLA_DIS.pdf: 1889802 bytes, checksum: 4fbb8e2e462022c1c29eeda8628a848b (MD5) / Made available in DSpace on 2018-04-03T16:52:03Z (GMT). No. of bitstreams: 1 FERNANDO_DE_OLIVEIRA_ANDRIOLA_DIS.pdf: 1889802 bytes, checksum: 4fbb8e2e462022c1c29eeda8628a848b (MD5) Previous issue date: 2018-01-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The purpose of this study was to evaluate cervical lordosis and head posture changes using lateral cephalographs after bimaxillary orthognathic surgery for mandibular prognatism by null hypothesis. Twenty-five patients with skeletal class III dentofacial deformities (10 men, 15 women; mean age, 29.28 ? 8.22 years; range 18-48 years) were included in this prospective clinical study. Lateral cephalographs were taken in natural head position (NHP) 2 weeks before and 6 months after orthognathic surgery. The reproducibility of the radiographer?s technique of taking radiographs in NHP was investigated using a photographic method and found to be acceptable. All measurements for cervical lordosis (CV1/CV2; CV3/CV7; CV1/CV7), head posture (NSL/OPT; NSL/VER) and other cephalometric values (NSL/Go-Gn; NSL/Ocl; Overjet) were repeated three times by the same investigator at 2- week intervals and the average values of the three measurements were calculated to use in statistical analysis. Intraclass correlation coefficients (ICC) ranged between 0.996 to 1.000, demonstrating a high reliability of the measures. Statistically significant differences were found for CV3/CV7 (P=0.006) and CV1/CV7 (P=0.005) and no significant differences were identified in head posture for both cranio-cervical and cranio-vertical angles. The null hypothesis was rejected. Orthognathic surgery resulted in significant cervical lordosis extension, and a tendency for head extension could also be observed. / O objetivo deste estudo foi avaliar, por hip?tese nula, a lordose cervical e as altera??es da postura da cabe?a usando telerradiografias de perfil ap?s cirurgia ortogn?tica bimaxilar para corre??o de prognatismo mandibular. Vinte e cinco pacientes com deformidades dentofaciais esquel?ticas classe III (10 homens, 15 mulheres, idade m?dia entre 29,28 ? 8,22 anos, intervalo de 18-48 anos) foram inclu?dos neste estudo cl?nico prospectivo. As radiografias laterais dos pacientes foram obtidas na posi??o natural de cabe?a (PNC) 2 semanas antes e 6 meses ap?s a cirurgia ortogn?tica. A reprodutibilidade da t?cnica do radiologista para realizar as tomadas radiogr?ficas na PNC foi investigada usando um m?todo fotogr?fico e considerada aceit?vel. As medidas para lordose cervical (CV1/CV2; CV3/CV7; CV1/CV7), postura da cabe?a (NSL/OPT; NSL/VER) e outros valores cefalom?tricos (NSL/Go-Gn; NSL/Ocl; Overjet) foram repetidas tr?s vezes pelo mesmo investigador em intervalos de 2 semanas e os valores m?dios das tr?s medidas foram calculados para serem usados na an?lise estat?stica. Os coeficientes de correla??o intraclasse (ICC) variaram entre 0,996 e 1,000, demonstrando uma alta confiabilidade das medidas. Foram encontradas diferen?as estatisticamente significativas para CV3/CV7 (P=0,006) e CV1/CV7 (P=0,005). N?o foram identificadas diferen?as significativas na postura da cabe?a para os ?ngulos cr?nio-cervical e cr?niovertical. A hip?tese nula foi rejeitada. A cirurgia ortogn?tica resultou em aumento significativo da lordose cervical (extens?o) e tamb?m em uma tend?ncia ? extens?o da postura da cabe?a.