Longitudinal behavior of facial and mandibular growth in patients with isolated Pierre Robin sequence

• Ano de defesa: 2017
• Autor(a) principal: Machado, Gabriela Letícia Clavisio Siqueira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Crescimento; Fotografia; Growth; Photography; Pierre Robin sequence; Sequência de Pierre Robin
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/61/61132/tde-13062017-110006/

The Pierre Robin sequence (PRS) is a congenital anomalie characterized by the occurrence of micrognathia, glossoptosis and cleft palate. Clinically is observed upper airway obstruction with consequent breathing and feeding difficulties. Individuals with PRS usually show retrognathia and a significantly convex facial profile in adulthood. The aim of this study was to assess the longitudinal behavior of facial growth of individuals with isolated PRS using photographs. Photographs of the right facial profile of 100 individuals were used (50 individuals with isolated PRS and 50 individuals without any craniofacial anomaly). The individuals with PRS were evaluated at 3 different times (T1: baby, T2: mixed dentition, T3: permanent dentition) measuring the facial convexity angle (G.Sn.Pog´). A comparison between T3 and control group (C), individuals without craniofacial anomalies and in permanent dentition, were also performed, checking the facial convexity, nasolabial (Ls.Sn.Cm), mentolabial (Li.Si.Pog´), facial inferior third (Sn.Gn´.C) angles and the ratio between medium anterior facial height and lower anterior facial height (MAFH/LAFH). The T3 group showed a facial convexity angle increased in relation to C group as well as the facial inferior third angle and the MAFH/LAFH ratio. In the longitudinal evaluation of individuals with isolated PRS, the significant difference occurred between T1 and T2 groups and T1 and T3 groups showing that facial convexity was higher in the baby phase and didn´t have a significant variation between the phases of mixed and permanent dentition. Individuals with isolated Pierre Robin sequence showed increased facial convexity in all phases evaluated but it decreased with their growth. When compared to individuals without anomalies, the PRS individuals continue with retrognathism in the permanent dentition. The facial inferior third angle and the MAFH/LAFH ratio increased suggest a lack of a chin projection to the maxilla, leading to a considerable number of orthognathic surgeries for the correction of discrepancies.