Estudo do efeito combinado dos lasers Er:YAG e Nd:YAG no preparo ósseo e na modulação do reparo peri- implantar em ratas com osteopenia induzida: estudo pré-clínico randomizado e controlado

Abstract

Osseointegration is a dynamic and multifactorial process that can be compromised under adverse systemic conditions. This study evaluated the effects of the combined use of Er:YAG laser (for osteotomy) and Nd:YAG laser (for photobiomodulation) on the osseointegration of titanium implants placed in the tibiae of ovariectomized Wistar rats with induced osteopenia. A total of 48 animals were divided into three groups: healthy control (C), osteopenic with conventional drilling (OVX), and osteopenic treated with the laser combination (OVX+L). Animals were evaluated at 15 and 45 days after implant placement. Analyses included biomechanical testing (push-in), serum alkaline phosphatase (ALP) quantification, total collagen assessment using Picrosirius Red staining, and histological morphological evaluation with hematoxylin-eosin staining. Results showed a significantly lower collagen deposition in the OVX+L group (p < 0.05) at 15 days, suggesting an early stimulus for bone matrix formation. However, no statistically significant differences were observed in biomechanical performance or ALP activity among the groups. Histological analysis revealed slight morphological improvement in the OVX+L group compared to the OVX group. It is concluded that the combined use of Er:YAG and Nd:YAG lasers promoted early peri-implant tissue responses, without leading to functional benefits in terms of mechanical strength or measurable biochemical activity within the evaluated periods. These findings highlight the need for further studies to clarify the therapeutic potential of this approach under conditions of low bone density.