Bloodflow and Bone Density after Distraction Osteogenesis with Hbo Treatment

Objectives: The purpose of this study is to investigate whether or not hyperbaric oxygen (HBO) treatment facilitates recovery of bloodflow and bone density in the distraction osteogenesis (DOG) region. Methods: Six adult beagle dogs were used in this experiment. The left maxillary incisors were removed to create bone defect (10 mm in length). The osteotomy for DOG was performed at the mesial site of maxillary third premolar, up to the left canine root level, then a bony segment including canine was made. After 3-day latency period, transportation of the segment into the bone defect area was performed by DOG (1mm/day) for 10 days. After the distraction period, three dogs treated by HBO (20days; 2.5ATA, 60mins/day) were used as experimental group. Three dogs that underwent 10 days of distraction without HBO treatment were used as control group. Using laser Doppler flowmetry, pulpal bloodflow of the maxillary canine was recorded for 100 days from the day of osteotomy. After the sacrifice, each palate was dissected and measured by pQCT (peripheral quantitative computed tomography) to investigate bone mineral density (BMD). These data were statistically analyzed using Mann-Whitney nonparametric analysis. Results: Pulpal bloodflow decreased just after osteotomy and recovered in 100 days in control group, and 70 days in experimental group, respectively, the difference in bloodflow recovery percentage on 70th day was significant between both groups. The cortical BMD was significantly higher in experimental group than that in control group. Conclusion: It is revealed that HBO treatment reduced recovery period of bloodflow and facilitated the cortical BMD. This study suggests that HBO treatment is useful as a treatment option to facilitate peripheral tissue reconstruction in the DOG region.