Histological investigation of improvement of jaw-bone structure for application of hydroxyapatite dental implant

Abstract

The purpose of this study was to investigate the possibility of applying the hydroxyapatite dental implant to the jaw-bone with atrophic structure. The lower P3, P4 and the mesial root of M1 of 6 mongrel dogs were extracted. At 4 months, the trabeculae were taken out and porous hydroxyapatite granules were filled in the vacant spongiosa. At 8 months, hydroxyapatite dental implants were placed into this area. After 1 week and after 2 months, specimens were taken out and fixed by 10% formalin alcohol. They were embedded in polyester resin and undecalcified thin sections were prepared. The sections were stained with toluidine blue and observed under light microscopy. Results: 1) A larger amount of bone compared with that of the peripheral spongiosa was observed among the granules. 2) One week after implantation, differentiation around the implant was rather slow in the area of the granules. But in the area of the granules next to the spongiosa, differentiation was normal. 3) Two months after implantation, a new bone was observed, which filled the implantation space and united the implant to the bone among the granules. But on some implant surface, a fibrous connective tissue was seen. These results suggest that this method is able to improve the jaw-bone structure sufficiently to apply the hydroxyapatite dental implant.