Effects of low level laser teraphy on new bone formation and relaps in the rat sagittal suture after expansion

The aim of this experimental study was to evaluate the effects of low level laser teraphy, on bone regeneration and relaps in the rat sagittal suture after expansion, histologically and radiographically Thirtysix 6-8 weeks old male Wistar rats were subjected to expansion, and 100 grams of force was applied to the sagittal sutur with an appliance during 7 days. All rats were separated into three equal groups (Control, Laser + Retansion, Laser). Control and laser + retansion grups were applied retansion appliance for 7 days. Laser + retansion and laser grups were exposed low level laser during retansion period. After retention period, 6 rats from each group were sacrified for histological assesment and 6 rats were remained for observating the relapse period. Computed tomography measurements were taken in the beginning (T0), after expansion period (T1), after retention period (T2), and after relapse period (T3). According to the histological findings , low level laser theraphy stimulated the bone formation. When we compared the relapse ratios of each group, minimum relapse was observed in the laser + retansion group. As a result of our study, applying low level laser therapy with retansion protocol after expansion, the retention period can be shortened and relapse can be reduced. Key words : low level laser therapy, new bone formation, rapid expansion, relapse, sagittal expansion