Changes in temporomandibular joint disc position and form following Herbst and fixed orthodontic treatment

• Autor(a) principal: Aidar, Luis Antonio de Arruda
• Data de Publicação: 2010
• Outros Autores: Dominguez, Gladys Cristina [UNIFESP], Yamashita, Helio Kiitiro [UNIFESP], Abrahão, Marcio [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• dARK ID: ark:/48912/001300000g787
• DOI: 10.2319/093009-545.1
• Texto Completo: http://dx.doi.org/10.2319/093009-545.1; http://repositorio.unifesp.br/handle/11600/32857
• topic: Temporomandibular joint; Magnetic resonance; Angle Class II malocclusion; Herbst therapy

Objective: To determine the changes in the position and form of the temporomandibular joint articular disc in adolescents with Class II division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliance (phase II).Materials and Methods: Thirty-two consecutive adolescents went through phase I of treatment and 23 completed phase II. the temporomandibular joints were evaluated qualitatively by means of magnetic resonance images at the beginning of treatment (T1), during phase I (T2), at the end of phase I (T3), and at the end of phase II (T4).Results: Significant changes in disc position were not observed with the mouth closed between T1 X T3 (P = .317), T3 X T4 (P = .287), or T1 X T4 (P = .261). At T2, on average, the disc was positioned regressively. With the mouth open, no difference was observed between T1 X T3 (P = .223) or T1 X T4 (P = .082). We did observe a significant difference between T3 X T4 (P < .05). Significant changes in the disc form were found with the mouth closed between T1 X T2 (P < .001) and T2 X T3 (P < .001).Conclusions: At the end of the two-phase treatment, in general terms, the position and form of the initial articular discs were maintained; however, in some temporomandibular joints some seemingly adverse effects were observed at T4. (Angle Orthod. 2010;80:843-852.)