INITIAL HEALING IN THE DOG OF SUBMERGED VERSUS NON-SUBMERGED POROUS-COATED ENDOSSEOUS DENTAL IMPLANTS

It has previously been reported that porous-coated root form endosseou s dental implants, became well integrated when used in the traditional 2-stage surgical approach. In this study, the placement of the implan t in a 1-stage (non-submerged) technique was to be explored. Implants were placed in the mandibles of dogs, and 2 designs were used differin g only in that one (experimental) had a 3-mm transgingival extension, permitting it to be exposed to the oral cavity from the outset. 12 (3 per animal) non-submerged implants were placed on 1 side of 4 beagle d ogs and 12 control (submerged) implants were placed contralaterally. A ll implants were allowed to heal for 6 weeks, after which histological preparations were made. 2 of 12 non-submerged implants were lost due to post-operative complications; otherwise, all implants healed uneven tfully. Histomorphometric analysis revealed bone-implant contact, as a ssessed by absolute bone contact (ABC) and contact length fraction (CL F), to be greater for the submerged design, suggesting that bone heali ng may be delayed with the non-submerged approach. As well, at this ea rly stage of healing, for both implant designs, ABC and CLF were signi ficantly greater on proximal than on buccal and lingual aspects. (C) M unksgaard, 1996.