FABRICATION AND PROPERTIES OF FUNCTIONALLY GRADED DENTAL IMPLANT

Dental implants with functionally graded structures composed of titani um (Ti) and ceramic hydroxyapatite (HAP) were fabricated to satisfy bo th mechanical and biocompatible property requirements. Specimens conta ining up to Ti/50%HAP functionally graded material (FGM) with the dime nsions 6 phi x 15 mm were successfully fabricated by CIP and sintering process. Miniature (2 phi x 10 mm) specimens of Ti, Ti/20%HAP FGM and Ti/30%HAP FGM implants were then made and inserted into femora of ten week-old Wistar strain rats to evaluate their biocompatibility. After 1, 2 and 4 weeks of implantation, the rats were killed and tissue blo cks containing the implant material were embedded in resin. Observatio n of bone formation around the implant was performed by both the conve ntional method by optical microscopy using specimens stained with tolu idine blue and the EPMA mapping method using unstained specimens. The observed area of new bone formation was in good agreement for both the light microscopy and EPMA elemental mapping method. Pure Ti and Ti/HA P FGM specimens showed no inflammation. When pure Ti and Ti/HAP FGM sp ecimens were compared, Ti/HAP FGM showed better biocompatibility. (C) 1997 Elsevier Science Limited. All rights reserved.