Clinical evaluation of implants following radical oral-cancer-surgery with/without adjuvant radiotherapy

Objectives: The aim of this study was to analyze the long-term implant survival in patients after ablative surgery of oral cancer with and without adjunctive radiotherapy. Methods: Between 1997 and 2006, 51 patients were treated with 188 dental implants. 30 implants were inserted in the upper and 158 implants in the lower jaw. 79 implants were placed in irradiated bone, 126 implants in residual bone, 62 implants in grafted bone and 108 implants in soft tissue transplants. 13 fixed bridges and 38 removable dentures (24 bar attachments, 7 telescopic and 7 ball retained dentures) were inserted. Results: 10 implant losses were encountered in 6 patients (5.3%). All losses occurred in the lower jaw. 5 implants were primary-losses after radiotherapy the other 5 implants were secondary-losses in one patient after 6.7 years (82 months) in grafted bone due to an operation of tumor recurrence. The overall 1-, 5- and 10-year cumulative survival rate of all implants was 97.3%, 97.3% and 80.6%. The survival percentage in irradiated bone was 93.8% (observation period 121 months) and 72.2% (115 months) in non-irradiated bone. The survival rate of implants placed without graft was 98.4% (65 months), when placed into bone as well as soft tissue grafts 70.3% (121 months), and 100% (94 months) when placed into a bone graft. Implants without tissue grafts were associated with a better survival rate 98.8% (94 months) than implants in tissue grafts (jejunual, mucosal flap) 78.5% (121 months). The difference of implant groups with and without tissue grafts was not significant (P=.278). All prosthetic restorations in patients without tumor recurrence could be maintained during the observation time. Conclusion: Implant placement respectively prosthetic loading of osseointegrated dental implants after ablative surgery of oral cancer with and without adjunctive radiotherapy does not seem to be more risk-encumbered than in healthy patients.