Differences in Osteoconduction at Porous Hydroxyapatite according to Pore Geometry.
- Author:
Choon Ki LEE
1
;
Bong Soon CHANG
;
Kug Sun HONG
Author Information
1. Department of Orthopedic Surgery, Seoul National University College of Medicine.
- Publication Type:Original Article
- Keywords:
Porous hydroxyapatite;
Pore geometry;
Osteoconduction
- MeSH:
Bone Marrow;
Bone Regeneration*;
Compressive Strength;
Durapatite*;
Haversian System;
Microscopy, Electron, Scanning;
Porifera;
Rabbits;
Tibia
- From:The Journal of the Korean Orthopaedic Association
1999;34(4):643-650
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: To assess the histological response and the reinforcing effects of bone ingrowth within porous hydroxyapatite implants depending on pore geometry. MATERIALS AND METHODS: Three types of porous hydroxyapatite (cylindrical, sponge and cross type) were prepared. Forty-two white rabbits were divided into 3 groups and 5x5x7 mm-sized porous hydroxyapatite block was inserted through the medial cortical window of a proximal tibia. Histomorphological changes were examined using light and scanning electron microscopy. Biomechanical compression test was performed using material test machine. RESULTS: At four weeks after implantation, the implants showed different histological changes depending on pore geometry. In cylindrical type porous hydroxyapatite, new bone was arranged in a concentric pattern around vessel similar to osteon. In sponge and cross type, irregular lamellar bone pattern was found. At 8 weeks, evidence of remodelling of new bone and bone marrow formation within porous hydroxyapatite was found. In biomechanical study, ultimate compressive strength significantly increased in all three implants after 8 weeks of implantation compared to preimplantation. CONCLUSIONS: In cylindrical type porous hydroxyapatite, new bone was arranged in a concentric pattern around vessel, and compressive strength was highest. Sponge type porous hydroxyapatite showed irregular lamellar bone pattern and was rather flexible and ductile. Cross type porous hydroxyapatite showed borderline pattern of both cylindrical and sponge type porous hydroxyapatite.
