The effects of diode laser (660 nm) on the rate of tooth movements: an animal study

Abstract

Low-level laser has been indicated to have the capability to facilitate the differentiation of the osteoclastic and osteoblastic cells which are responsible for the bone remodeling process. The aim of this study was to evaluate the effects of InGaAlP laser with a wavelength of 660 nm on the rate of tooth movement and histological status. Thirty male Wistar rats of 7 weeks old were selected for this study. The rats were randomly divided into two groups of 15 each to form the experimental (laser-irradiated) and control (non-irradiated) groups. The control group received unilateral orthodontic appliance design (one quadrant), but the laser-irradiated group received split-mouth design, with orthodontic appliance on both sides and laser irradiation on one side only (group b) and on the contralateral side (group c). The orthodontic appliance consisted of a NiTi closed coil spring with a length of 5 mm which was ligated to maxillary molar and incisor. A total of 60 g of force was applied to the rat molar. The diode laser (660 nm) was irradiated with an output power of 25 mW in continuous mode for a total time of 5 min in the laser-irradiated group. After 14 days of orthodontic tooth movement, the amount of tooth movements was measured. In the laser-irradiated group, the amount of tooth movement was significantly greater than that of the non-irradiated group (2.3-fold), but there was no significant difference between the non-irradiated and indirectly irradiated groups. Histopathological studies revealed that the number of osteoclasts in the laser-irradiated group was significantly greater than that of the non-irradiated group (1.5-fold) while this number was almost the same in the non-irradiated and indirectly irradiated groups. The results suggested that low-level laser can accelerate the rate of bone remodeling. However, in order to utilize the low-level laser as an adjunct in orthodontic practice on patients, further research studies are needed for finding the appropriate dosage for the human tissues.

Efficiency of low-level laser therapy for orthodontic tooth movement: a review

“…Moreover, some animal studies have shown that laser diode irradiation can increase the amount of tooth movement (2-to 3-fold) in rats [18,19]. These results are consistent with other animal studies [7].…”

Efeito do LED infravermelho sobre a movimentação dentária induzida em ratos

“…No presente trabalho foi empregada a microtomografia computadorizada in vivo para quantificar o deslocamento dentário, diferente dos estudos de A maioria das pesquisas, clínicas ou em animais experimentais, em ortodontia, que investigam o efeito da luz infravermelha durante a movimentação dentária, relacionam a aplicação do laser durante movimentação ortodôntica (Lim et al, 1995;Kawasaki;Shimizu, 2000;Cruz et al, 2004;Limpanichkul et al, 2006;Turhani et al, 2006;Seifi et al, 2007;Youssef et al, 2008;Fujita et al, 2008;Tortamano et al, 2009;Yoshida et al, 2009;Abi-Ramia et al, 2010;Habib et al, 2010;Gama et al, 2010;Marquezan et al, 2010;Yamaguchi et al, 2010;Sousa et al, 2011;Altan et al, 2012;Duan et al, 2012;Habib et al, 2012;Bicakci et al, 2012;Marquezan et al, 2013;Cossetin et al, 2013;Genc et al, 2013;Velásquez 2013;Kansal et al, 2014;Seifi et al, 2014;Hevari et al, 2014;Shirazi et al, 2015;Domínguez et al, 2015). O LED é pouco investigado como fonte de energia luminosa para verificar sua influência durante o movimento ortodôntico.…”

“…Assim, Shirazi et al(2015), com grupo experimental de 14 dias e coloração H&E, Altan et al(2012) Os efeitos do laser na polpa dentária, foi um aspecto reportado apenas por Abi-Ramia et al (2010); em seu estudo foram realizados cortes histológicos longitudinais e coloração H&E, e concluíram que a movimentação dentária induzida associada ao laser de baixa potência mostrou uma hiperemia reversível como uma resposta tecidual ao estímulo e que o laser permite um reparo mais rápido do tecido pulpar durante a movimentação ortodôntica.…”

“…O efeito do laser na resposta tecidual durante a movimentação dentária induzida apresenta algumas controvérsias: alguns autores afirmam que a quantidade de movimento aumenta (Kawasaki;Shimizu,2000;Fujita et al, 2008;Yoshida et al, 2009;Yamaguchi et al, 2010;Altan et al, 2012;Duan et al, 2012;Shirazi et al, 2015), enquanto outros autores não encontraram nenhuma diferença entre os grupos controle e experimental. (Seifi et al, 2007;Gama et al, 2010;Marquezan et al, 2010;Altan et al, 2012;Seifi et al, 2014).…”

“…Alguns autores afirmam que há um aumento do número de osteoclastos (Kawasaki;Shimizu, 2000;Fujita et al, 2008;Yoshida et al, 2009;Habib et al, 2010;Yamaguchi et al, 2010;Altan et al, 2012;Cossetin et al, 2013;Shirazi et al, 2015) entretanto outros afirmam a diminuição do número de células clásticas (Fonseca et al, 2013).…”