Treatment of experimental mandibular osteomyelitis with hyperbaric oxygen and antibiotics

Osteomyelitis was created in surgically fractured rabbit mandibles by the inoculation of Bacteroides melaninogenicus. After the disease was established, the animals were randomly divided into four groups: Group I, 16 animals, received hyperbaric oxygen (HBO) treatment alone (100% oxygen at two atmospheres pressure absolute for 2 hours daily for 40 treatments); Group II, eight animals, were untreated controls; Group III, five animals, received HBO therapy plus antibiotic treatment; and Group IV, five animals, received antibiotic treatment alone. At completion of 40 treatments, end-point assessment of the disease was performed by bacterial cultures, quantitative mobility measurements, subjective scoring, and microscopic examination of tissue to detect signs of oxygen toxicity. Mandibular osteomyelitis was not eliminated in any of the animals in this study, regardless of treatment. There was significantly greater stability in Group I (HBO treatment alone) than in Group II (untreated) animals (p less than 0.01). There was no significant difference, however, between animals in Group III (HBO and antibiotics) and Group IV (antibiotics alone) (p less than 0.05). No detrimental effects of hyperbaric oxygen therapy delivered at two atmospheres pressure for 80 h were observed.