Avaliação histomorfológica da movimentação dentária induzida em ratos com diferentes tipos de força sob ação da terapia a laser em baixa intensidade

• Autor(a) principal: Dias, Laércio Santos [UNESP]
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/108925
• topic: Movimentação dentária; Lasers; Rato; Tooth Movement

Orthodontic tooth movement has been defined as the result of a biological response to an externally applied force dependent on remodeling in periodontal ligament and alveolar bone requiring active participation of the cellular levels. Whereas low-level laser therapy (LLLT) includes anti-inflammatory and biostimulatory effect, it is assumed that this therapy promotes significant effects during tooth movement. Thus, the aim of this study was to measure the amount of tooth movement in an experimental rat model and to describe the relevant microscopic aspects resulting from induced tooth movement, with different types of orthodontic forces, associated with LLLT. 108 Wistar rats were divided into two groups according to the application of LLLT. Both groups were subdivided according to the type of force used: continuous (CF), continuous-interrupted (CIF) and intermittent (IF). All subgroups were evaluated in three periods of five, seven and nine days. Each group was then divided into three subgroups to evaluate changes in time intervals of five, seven and nine days. Opened springs NiTi (Sentalloy) were installed, releasing 50cN magnitude of force, being maintained disabled or removed to establish the types of force, CF, CIF e IF. Data were compared by analysis of variance (ANOVA) and t-Student test with a significance level of 5%. The histomorphological analysis showed that both bone and periodontal tissues responded differently considering the type of force used and the LLLT promoted a more tolerable biological response enhancing the rate of tooth movement. It is concluded that LLLT promoted an increase in the amount of movement in all subgroups and the CF associated with LLLT promoted the highest rates of movement; CIF associated with LLLT provided the most tolerable biological response and IF, according to the quantitative and qualitative parameters, was the less effective force, regardless of the LLLT.