Treatment outcome of immediately loaded implants installed in edentulous jaws following computer-assisted virtual treatment planning and flapless surgery

Objectives: The objective was to evaluate the outcome of immediately loaded implants installed in edentulous jaws following computer-assisted virtual treatment planning combined with flapless surgery. Material and methods: Twenty-nine edentulous patients (9 females, 20 males, mean age of 71.5 years) were treated using the Nobel Guide (TM) protocol for surgical planning, fixture installation and immediate functioning of a prefabricated fixed implant prosthesis. One hundred and seventy-six fixtures were installed to support 21 maxillary and 10 mandibular reconstructions. Patients were followed for up to 44 months. Results: Nineteen out of 176 fixtures were lost between 2 and 18 months after installation. Fixture survival rate was 89% (92% maxilla, 83% mandible). Implant-supported suprastructures remained stable during the follow-up period in 26 out of 31 jaws (90% maxilla, 70% mandible). Surgical or technical complications occurred in 42% of treated cases. Misfit of abutment-bridge appeared in five cases, resulting in disconnection of the bridge in two patients where fixtures were left for unloaded healing. Fixture losses resulted in the removal of the suprastructure in three patients, who returned to removable dentures. Extensive adjustments of occlusion were made in 10% of the immediately connected bridges. Radiographic bone defects developed in three patients after drilling, which appeared in two cases after anchor-pin drilling in the maxilla and another in a severely resorbed mandible. Conclusion: The patient's post-operative discomfort such as swelling and pain was almost negligible. However, compared to conventional protocols, the occurrences of surgical and technical complications were higher, and thus this method must still be regarded to be in an exploratory phase.