Pattern of osteogenesis during onlay bone graft healing.

Objective: The aim of this paper was to analyze how healing occurs between onlay bone graft and the mandible cortex.

Study Design: Autologous and allogeneic corticocancellous bones, harvested from the ilium wing, were grafted at each mandible side of 40 rabbits. One side received platelet-rich plasma (PRP). Killings occurred at 3, 7, 14, 28, and 56 days. Tissues were stained by hematoxylin-eosin and toluidine blue. New bone area was measured at different regions of sections stained with toluidine blue. Wilcoxon test was used to analyze differences among regions and Bonferroni test to analyze the influence of PRP, graft nature, and days.

Results: Osteogenesis was higher at the lateral region (P < .05). PRP tended to improve bone neoformation, which was higher at the allogeneic graft. Statistical significance among the different categories of variables-grafts, use of PRP, and days of observation-did not have a linear behavior. A linear behavior of statistical tests was not detected. Bone new formation increased until the 14th day (P < .05).

Conclusions: Onlay grafts heal due to osteogenesis which occurs at the lateral region and between the cortex and host mandible. Allogeneic grafts and PRP tend to improve bone formation.