Demineralized Xenogenic Dentin and Autogenous Bone as Onlay Grafts to Rabbit Tibia.

PURPOSE: The present study was undertaken to evaluate the healing pattern of xenogenic demineralized dentin onlay grafts in comparison with autogenous bone grafts to the rabbit tibia.

MATERIAL AND METHODS: Eight 6-month-old New Zealand male rabbits were used in the experiments. Standardized sized dentin blocks from human premolars and similar autogenous bone blocks harvested from tibia were grafted as onlay blocks on each tibia (n = 8 × 2). All animals were killed after a healing period of 12 weeks.

RESULTS: Healing was uneventful for all animals. In general, both the dentin and bone block grafts were fused to the bone, resorbed, and replaced by bone and connective tissue to a varying degree. Both types of grafts were still present after 12 weeks, on an average to approximately one third of the original sizes. Resorption cavities could be seen in the dentin with bone formation. Zones of osseous replacement resorption of the dentin could be noted. In both graft types, higher rate of bone formation was seen at the interface between graft and recipient site.

CONCLUSION: Demineralized xenogenic dentin onlay grafts showed similar resorption characteristics as autogenous bone onlay grafts, being resorbed in a similar rate during 12 weeks. New bone formation occurred mainly in terms of replacement resorption in the interface between dentin/bone graft and native bone.