Permucosal implantation pilot study with HA-coated dental implant in dogs

The histological response of transmucosal one-stage titanium dental implants coated with hydroxyapatite is described. The gingival adhesion to the implant was examined with regard to coated, partially coated or non-coated surfaces in the cervical region. From each coating type, 9 implants were inserted into dogs. Six months after the insertion, 19 implants could be evaluated, but 8 implants were lost. From these 19 implants, 6 implants showed severe pockets with inflammation up to the bony tissue. The 13 successful implants showed direct bone bonding with the hydroxyapatite coating and adhesion of submucosal connective tissue to the implant surface, with inflammation. The marginal gingiva showed slight inflammation. A totally coated implant will probably introduce inflammation by debris formation against the rough implant surface more easily. The hydroxyapatite coating often disappeared in the soft tissue or in the oral cavity. Bone which directly adapted to the coating seemed to prevent it from resorption.