Tooth Movement After Infrared Laser Phototherapy: Clinical Study in Rodents

Abstract

Objectives: The aim of this research was to investigate the influence of low-power laser on tooth movement in rats. Background: Tooth movement is closely related to the process of bone remodeling. The biologic result, with the application of a force to the tooth, is bone absorption on the pressure side and neoformation on the traction side of the alveolar bone. The laser photobiomodulation is capable of providing an increase in cellular metabolism, blood flow, and lymphatic drainage. Methods: Thirty young-adult male Wistar rats weighing between 250 and 300 g were divided into two groups, control and experimental, containing 15 animals each. The animals received orthodontic devices calibrated to release a force of 40 g/F, with the purpose of moving the first upper molar mesially. Low-intensity laser, wavelength 790 nm, was used in the experimental group; the dose was 4.5 J/ cm 2 per point, mesial and distal, on the palatal side, 11 J/cm 2 on the buccal side, and this procedure was repeated every 48 h, totaling nine applications. The active movement was clinically evaluated after 7, 13, and 19 days. Results and conclusion: The results showed no statistically significant difference, p ¼ 0.079 (T0-T7), p ¼ 0.597 (T7-T13), and p ¼ 0.550 (T13-T19) between the laser and control groups on the amount of tooth movement in the different times evaluated. It may be concluded that laser phototherapy, with the parameters in the present study, did not significantly increase the amount of tooth displacement during induced orthodontic movement in rodents.

Photobiostimulation as a modality to accelerate orthodontic tooth movement

“…16 Three other separate studies, using different methodologies (e.g., fewer laser applications, extra-oral application of laser, and higher orthodontic forces) found no significant difference between photobiostimulation and controls in affecting the rate of OTM. [23][24][25] Similar benefits of increased OTM were not seen in beagle dogs at 2 months of LLLT despite histological evidence suggestive of increased osteoclastic activity. 26 With regard to the use of LED, conclusions from the limited number of LED studies suggest that it does not have an effect on tooth movement.…”

Effects of medications and laser on induced tooth movement and associated root resorption: four key points

“…1,3,4,5,[7][8][9][10][11][12][14][15][16][17][18]20,[23][24][25][26] We describe four fundamental points for experimental models to ensure that the evaluation of the effects of medication and phototherapy on induced tooth movement and associated root resorption is free of external influence.…”

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.…”

“…Poucos trabalhos avaliam a movimentação em ratos por um período superior a 14 dias (Yoshida et al, 2009;Gama et al, 2010;Ekizer et al, 2015), sendo necessário trabalhos que investiguem períodos mais tardios da movimentação.…”

“…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). Os achados sobre a quantidade de reabsorção radicular também mostraram resultados conflitantes; alguns autores afirmam que a luz infravermelha diminui a reabsorção radicular (Fonseca et al, 2013;Seifi et al, 2014;Ekizer et al, 2015) enquanto outros autores não encontraram diferença entre os grupos.…”