Custom-made root analogue titanium implants placed into extraction sockets. An experimental study in monkeys

The aim of this investigation was to evaluate clinically and histologically a new custom-made, root analogue titanium implant placed into extraction sockets in monkeys (Macaca fascicularis). Three adult monkeys were used in this investigation. After raising full thickness flaps on the buccal and lingual side, the upper central and lateral incisors were extracted. Each tooth root was machine copied to 1 titanium analogue using a new CAD/CAM-system. The implants were installed in the respective extraction sockets and the flaps sutured back. After 6 months of healing biopsies were taken and processed according to the cutting-grinding technique. The percentage of mineralized bone-to-implant contact was measured as a fraction of the rough implant surface using computer-assisted analysis. The main clinical problem that occurred during implant placement was the fracture of the buccal alveolar wall. The histometric evaluation showed a mean mineralized bone-to-implant contact of 41.2 +/- 20.6%. In this investigation it could be shown that implants fabricated by laser copying will osseointegrate. The presented data encourage the performance of clinical and experimental trials evaluating the new system utilizing improved second generation CAD/CAM equipment. Such studies are currently underway.