SYNOPSIS
Purpose: The aim of this study was to examine effects of hydroxyapatite fiber (HF) combining with autogenous Bone on vertical bone augmentation.
Materials and methods: Polytetrafluoroethylene chambers were fixed to the parietal bone on the right and left sides in thirty-six Japanese male white rabbits. HF only (30 or 60 mg) and combination of HF with autogenous bone from tibia at different ratios (30 mg bone/HF ratio: 3/1, 3/2, 1/1) were grafted into each chamber. Chambers were left empty in the negative control animals (empty group). Rabbits were sacrificed at 4 and 8 weeks. Then, total bone volume (TBV) of highly calcified bone region in the chamber was quantified with micro-CT analysis. Histomor-phometric analysis was performed to evaluate the area of newly formed bone (BA). Statistical analysis was performed with the Student t-test and Tukey-Kramer's method.
Results: In histology, newly formed bone conducted by HF showed a particular structure, and active bone regeneration was observed in the groups containing more HF at 8 weeks. From 4 weeks to 8 weeks BA was significantly reduced in the control, HF 30 mg and ratio 3/1 groups. At 8 weeks BA of HF 60mg was signifi-cantly higher than the one of HF30mg group.
Conclusions: Combination of HF with autogenous bone was effective in vertical bone augmentation although optimal ratio of the combination needs further study.

Key words: hydroxyapatite fiber, bone augmentation, bone graft, bone substitute, osteoclast