Avaliação da fidelidade da referência externa em tecidos moles na cirurgia ortognática da maxila

• Autor(a) principal: Souza, Ramiro Beato
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/14114
• topic: Orthognathic surgery; Maxillary repositioning; Le Fort I maxillary osteotomy; External reference points; Cirurgia ortognática; Posicionamento maxilar; Osteotomia maxilar tipo Le Fort I; Referência externa.; Boca - Cirurgia; Osteotomia de Le Fort; CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA::CIRURGIA BUCO-MAXILO-FACIAL

The aim of this study was to analyze the accuracy of external reference placed in soft tissue nasion for vertical maxillary repositioning. Forty patients with dentofacial deformities who were to undergo Le Fort I maxillary osteotomy were separated into two groups to evaluate two different external reference measurement techniques: soft tissue nasion (study group) and Kirschner pins (control group). Data were collected in two phases. Initially the vertical position of the maxilla was assessed during surgery before Le Fort I osteotomy and after maxillary fixation, in relation to the external reference point, evaluating the intra-operative vertical alteration of each case. In the second phase, maxillary vertical measurements were done using the pre and pos-operative cephalometric radiographs to assess their radiographic vertical alteration. Differences among radiographic and intra-operative vertical variations of the maxilla were calculated to acquire values corresponding to discrepancies in maxillary positioning in relation to upper central incisor. Results were statistically compared and analyzed. The average of accuracy of vertical maxillary positioning was 0.525 mm for the control group and 0.650 mm for the study group. Student t test indicated no significant difference between both methods (P=0.429). In conclusion it was noted that both techniques were efficient for vertical maxillary repositioning and soft tissue nasion method showed a similar accuracy of that obtained with Kirschner pins.