Enhancing bone formation using absorbable AZ31B magnesium alloy membranes during distraction osteogenesis: A new material study.

PURPOSE

To investigate whether the use of absorble AZ31B magnesium alloys over distraction gaps improves the quality and quantity of regenerated bone better than the use of Collagen membranes.

METHODS

Fifteen mixed-breed dogs were randomly divided into the experimental (n = 10) and control (n = 5) groups. In the experimental group, two devices were implanted along the mandible; one side with absorble AZ31B and the other side with Collagen. The control animals did not undergo osteotomy or distraction. After a consolidation time of two months, 30 specimens were harvested, and newly created bone was identified using CBCT and micro-CT.

RESULTS

The Collagen membranes were absorbed completely, and the AZ31B membranes became irregular and rough. Mandible length was successfully extended approximately 1 cm. More bone formation was found after using AZ31B than Collagen, and there was a significant difference in width reduction between experimental sites treated with AZ31B (0.11 ± 0.04 cm) and Collagen (0.42 ± 0.06 cm) (p < 0.05). Trabecular thickness was also significantly higher in AZ31B (0.338 ± 0.08 cm) and control (0.417 ± 0.05 cm) than Collagen (0.178 ± 0.04 cm) (p < 0.05).

CONCLUSION

An AZ31B membrane barrier is biocompatible and absorbable which can maintain the distraction gap and provide support to the attached osteoprogenitors by providing space for them to proliferate.