Bone regeneration in rabbit nasal bone by laser pulse shape control CO2 laser

This study investigated the relationship between total short-pulse CO 2 laser irradiation intensity and bone regeneration in rabbit nasal bone. Forty-eight rabbits (12- 16 weeks: 2.5-3.0 kg) were used in this study. After the cranial bone was exposed under general anesthesia, CO 2 laser irradiation was applied directly to the nasal bone under various conditions. Laser irradiation pulses with a spike pulse width of 360 ns, a pulse tail length of 92.6 ms, and an irradiation intensity per pulse of 650 mJ/ cm 2 were applied in a multipulse mode at a frequency of 50 Hz. The rabbits were divided into four groups of six, in which a energy density of 88 J/cm 2 (Group A), 220 J/cm 2 (Group B), 441 J/cm 2 (Group C), or 661 J/cm 2 (Group D) was applied. The rabbits were sacrificed 8 and 16 weeks after the procedure, and tissue sections were assessed histologically. Bone regeneration in the maxillary sinus was observed in groups A, B, and C at 8 and 16 weeks, but not in group D. The surface area ratio of new bone was significantly higher in group A. 88 J/cm 2 was the most effective energy density for bone regeneration.