Modeling of the buccal and lingual bone walls of fresh extraction sites following implant installation

Mauricio G. Araújo, Jan L. Wennstro¨m, Jan Lindhe
Clin. Oral Impl. Res. 17, 2006 / 606–614

The objective of this study is to determine whether the reduction of the alveolar ridge that occurs following tooth extraction and implant placement is influenced by the size of the hard tissue walls of the socket. For this study we use the third premolar and first molar in both quadrants of the mandible of six beagle dogs. Mucoperiostal flaps were elevated and the distal roots were removed. After that, implants were installed in the fresh extraction socket in one side of the mandible. The flaps were replaced to allow a semi-submerged healing. The procedure was repeated in the contra later side of the mandible after 2 months. 1 month after the final implant installation, the animals were sacrificed and the mandibles were dissected, so and each implant site was removed and processed for ground sectioning. Our results shows a marked hard tissue alterations that occurred during healing following tooth extraction and implant installation in the socket. The marginal gap that was present between the implant and the walls of the socket at implantation disappeared as a result of bone fill and resorption of the bone crest. The modeling in the marginal defect region was accompanied by marked attenuation of the dimensions of both the delicate buccal and the wider lingual bone wall. Bone loss at molar sites was more pronounced than at the premolar locations. From this study, we was lead to conclude that implant placement failed to preserve the hard tissue dimension of the ridge following tooth extraction. The buccal as well as the lingual bone walls were resorbed. At the buccal aspect, this resulted in some marginal loss of osseointegration.