Histomorphometric and microtomographic evaluation of the effects of hyperbaric oxygen and systemic ozone, used alone and in combination, on calvarial defect healing in rats

Purpose The aim of this study was to compare the efficacy of hyperbaric oxygen and systemic ozone, used separately and in combination, on the healing of bone defects. Material and Methods Sixty male Wistar rats were divided into 4 groups (n = 15) according to treatment (control, hyperbaric oxygen [HBO], ozone [O], and HBO plus O [HBO-O]) and divided further into 3 subgroups according to day of sacrifice (postsurgical days 5, 15, and 30). Surgery was performed under general anesthesia to create a critical-size bone defect (5 mm in diameter) in the cranium. After sacrifice, microtomographic images of all samples were recorded, and histomorphometric analysis was performed. Results Histologic and radiologic measurements showed that the values of all experimental groups were higher than those of the control group. Histologic scores for all experimental groups were statistically higher than those for the control group day 30 (O, P =.045; HBO, P =.049; HBO-O, P =.042). Histologic scores also were statistically higher for the HBO group on day 5 (P =.045) and day 15 (P =.009) compared with the control group. Microtomographic scores were higher for the experimental groups than for the control group, with statistically significant differences for group O on day 5 (P =.033) and day 30 (P =.0045) and for group HBO on day 15 (P =.005). Histologic and radiologic analyses showed positive correlations. Conclusion Within the limitations of this study, the use of hyperbaric oxygen and ozone, separately and in combination, were shown to be effective in increasing bone healing. Combined usage was no more effective in stimulating bone healing than separate usage.