Slow and rapid maxillary expansion in patients with bilateral complete cleft lip and palate: a cephalometric evaluation

• Ano de defesa: 2016
• Autor(a) principal: Gregorio, Leonardo Vieira Lima
• 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: Cefalometria; Cephalometry; Cleft Lip and Palate; Expansion Technique; Fissura de Lábio e Palato; Técnica da Expansão Palatina
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/61/61132/tde-19102016-151304/

Introduction: The objective of this study was to compare the dentoskeletal effects of the slow (SME) and rapid maxillary expansion (RME) in patients with bilateral complete cleft lip and palate (BCLP). Methods: The sample comprised 46 patients with BCLP (34 male and 12 female) with a mean age of 9,2 years. They were randomly assigned into two groups: Group RME comprised 23 patients with posterior crossbites treated with Hyrax or Haas appliances. Group SME comprised 23 patients with posterior crossbites treated with quad-helix appliance. Both expansion modalities were performed prior to secondary alveolar bone graft procedure. Conebeam computed tomography (CBCT) was performed before expansion (T1) and after appliance removal at the end of a 6-month retention period (T2). Sagittal and vertical changes were evaluated using the cephalometric reformatted images that were obtained from the CBCT. Cephalometric analysis was performed using Dolphin Imaging Software (Chatsworth, CA, USA). Intraclass correlation coefficient (ICC) was used to calculate intraexaminer agreement. Intragroup changes were evaluated using paired t test. Intergroup comparisons were performed using t test (p<0.05). Results: The intraexaminer agreement was excellent (ICC varied from 0.88 to 0.96). RME group showed a significant increase of lower anterior facial height (p=0.042), mandibular length (p= 0.003) and maxillomandibular difference (p=0.006). SLM group demonstrated an increase of mandibular length (p<0.001) and maxillomandibular difference (p<0.001) and a decrease of the ANB angle (p=0.034). No significant differences between RME and SME were found. Conclusions: Rapid and slow maxillary expansion produced similar sagittal and vertical changes in patients with BCLP