Effects of hyperbaric oxygen therapy on an accelerated rate of mandibular distraction osteogenesis.

Background: Distraction osteogenesis has become a standard therapy for lengthening of the human craniofacial skeleton. Because the technique is used predominately in a paediatric population, limiting the treatment protocol is beneficial.

Methods: Twenty-four animals were divided into four groups with distraction rates of 1mm and 2mm/day with and without hyperbaric oxygen (HBO) therapy. Following a 5-day latency period, mandibular lengthening of 15mm was performed with a uniaxial distractor along the body of the mandible. Consolidation period was 4 weeks in all groups. HBO therapy was administered to one of the 1 and 2mm/day groups 1 day preoperatively, throughout the latency and distraction phases and 2 weeks into the consolidation period. Animals were euthanised after consolidation and the mandibles harvested for bone mineral densitometry evaluation.

Results: The mean bone mineral density (BMD) (g/cm(2)) was 0.208+/-0.04 in Group 1 (1mm/day distraction, no HBO therapy), 0.228+/-0.09 in Group 2 (1mm/day distraction, + HBO therapy), 0.180+/-0.1 in Group 3 (2mm/day distraction, no HBO therapy), and 0.269+/-0.05 in Group 4 (2mm/day distraction, + HBO therapy). Using the Student's t-test for equality of means and the one-way analysis of variance (ANOVA), we found that the mean BMD was significantly higher in the groups that were administered HBO (Groups 2 and 4) than not (P=< 0.05). For the groups that had distraction of 1mm/day and 2mm/day, those that underwent HBO therapy had significantly higher BMD than those without HBO therapy (P=< 0.05).

Conclusion: We have found that HBO therapy may serve to augment the healing process in distraction osteogenesis, allowing for more rapid distraction in order to decrease the overall treatment time.