[Experimental investigation on application of hydroxyapatite implant to alveolar ridge augmented by porous hydroxyapatite granules--histological observation on implant and implant covered with autogenous iliac bone].
UNLABELLED: The purpose of this study was to investigate the possibility of applying the hydroxyapatite implant and the hydroxyapatite implant covered with autogenous iliac bone to the augmented mandible. Three months after the extractions of the lower P3, P4, and M1 of mongrel dogs, alveolar ridge augmentations were performed widely with porous hydroxyapatite granules. After one month, the hydroxyapatite implants were inserted in the iliac bone of the same dog. Four months after the augmentation, the hydroxyapatite implant and the hydroxyapatite implant covered with autogenous iliac bone were implanted only in the augmented area with the granules of the mandible. Two months later, specimens were taken out and fixed by 10% formalin alcohol. They were embedded in polyester resin and undecalcified sections were prepared. The sections were stained with toluidine blue and observed under light microscope. RESULTS: 1) Bone ingrowth was seen in most parts of the intergranular spaces and in some spaces fibrous connective tissues were observed. 2) The hydroxyapatite implant was partly attached to the bone. But a large surface of the implant was connected to the fibrous tissues among the granules. 3) The hydroxyapatite implant covered with the iliac bone was combined with the bone of the intergranular spaces.