High-intensity Nd:YAG laser accelerates bone regeneration in calvarial defect models.

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Laser Physics

Background:

• High-power pulsed lasers show potential for bone anabolism.
• In vivo evidence for laser-induced bone repair is limited.
• Neodymium-doped yttrium aluminium garnet (Nd:YAG) lasers offer a potential therapeutic modality.

Purpose of the Study:

• To investigate the efficacy of a Q-switched, pulsed Nd:YAG laser in promoting bone defect repair.
• To evaluate laser-induced bone regeneration in calvarial defect models in rats and rabbits.
• To assess the effect of laser irradiation on bone defects, both empty and filled with collagen sponge.

Main Methods:

• Utilized bilateral calvarial defect models (5mm rat, 8mm rabbit).
• Applied Nd:YAG laser irradiation (1064 nm, 15 pps, 0.75 W, 344 J/cm²) every two days for two weeks.
• Compared outcomes in empty defects and those filled with collagen sponge, with varying output power in rabbits (0.75 W and 3 W).
• Evaluated new bone formation using micro-computed tomography and histological analysis at four weeks post-surgery.

Main Results:

• Laser irradiation significantly increased new bone formation by approximately 45% in both empty and collagen sponge-filled defects compared to controls.
• Both tested output powers (0.75 W and 3 W) in rabbit models enhanced bone regeneration, with no significant difference between them.
• Demonstrated consistent beneficial effects of Nd:YAG laser treatment on bone healing in vivo.

Conclusions:

• Nd:YAG laser irradiation effectively promotes bone regeneration in calvarial defects.
• The laser shows potential as an adjunctive therapy for enhancing local bone healing post-surgery.
• Further research into optimal laser parameters could refine its clinical application in bone repair.