Alveolar ridge repair using resorbable membranes and autogenous bone particles with simultaneous placement of implants: An experimental pilot study in dogs

The aim of this experimental study was to evaluate the use of autogenous bo ne harvested during preparation of implant sites in combination with resorb able membranes for vertical ridge augmentation under 2 different defect sit e conditions. Combined vertical/horizontal alveolar bone defects were creat ed by experimentally induced periodontal infections around all premolar tee th in the mandibles of 3 dogs (group 1). In another 3 dogs, fresh surgical defects were created after extraction of all premolar teeth in the mandible s (group 2). In all dogs, 2 implants were placed on each side of the mandib le into the defect areas. One implant on each side of the mandible received augmentation with autogenous bone particles, and both implants on one side of the mandible were covered with polylactic acid membranes. After 5 month s, the material was evaluated histologically. There was a small but signifi cant increase in bone regeneration in the defects augmented with bone parti cles with and without membrane coverage in group 1. In group 2 no significa nt difference was seen between the controls and the augmented sites. The ma jor limiting effect for bone regeneration appeared to be insufficient stabi lity of the bone material to withstand the overlying soft tissue pressure. It was concluded that the placement of autogenous bone particles, either wi th or without membrane coverage, had little effect on the regeneration of p eriimplant bone defects.