Comparative study of flame spraying apatite coating titanium and titanium dental implants

Histological findings around the implants

Abstract

Thc purpose of this study was to compare the tissue response to titanium implants coated with hydroxylapatite by flame spraying (AFC implants) and conventional titanium (Ti) implants. Eight beagle dogs were studied. Three months after the extraction of their premolars, two AFC implants were inserted in one side of the mouth and two Ti implants were inserted in the other. The animals were sacrificed after 2 weeks and 1, 3 and 6 months. Non-decalcified sections, 15 μm in thickness, were made with a cutting-grinding system and stained with toluidinc blue for histological examination.
The following results were obtained:
1) Direct bone bonding to the AFC surface occurred earlier than direct bone contact to the Ti surface.
2) Comparable bone remodelling occurred around both types of implants at 6 months postoperatively.
3) Non-cellular solubilization of HA granules and phagocytosis of HA granules by mononuclear and multinuclear cells were detected around the bone-free HA surface. At the apex of sonic AFC implants, the coating layer had disappeared at 6 months postoperatively.
4) Mononuclear cells were observed on Ti implants. The number of these cells diminished 3 months after implantation.
5) These results suggested that AFC implants had the advantage of earlier stabilization by bone than Ti implants. However, further studies are warranted on reactions to the HA coating during long-term application.