Dental implants in patients with head and neck cancer - a systematic review and meta-analysis of the influence of radiotherapy on implant survival.

PURPOSE The purpose of this meta-analysis was to compare implant survival in irradiated and non-irradiated bone and to investigate potential risk factors for implant therapy in oral cancer patients. MATERIAL AND METHODS An extensive search in the electronic databases of the National Library of Medicine was performed. Systematic review and meta-analysis were conducted according to PRISMA statement. The meta-analysis was performed for studies with a mean follow-up of at least three and five years, respectively. RESULTS The systematic review resulted in a mean overall implant survival of 87.8% (34-100%). The meta-analysis revealed a significantly higher rate of implant failure in irradiated bone compared to non-irradiated bone (p<0.00001, OR 1.97, CI [1.63, 2.37]). The studies also showed that implants placed into irradiated grafted bone were more likely to fail than those in irradiated native bone (p<0.0001, OR 2.26, CI [1.50, 3.40]). CONCLUSION Even though overall implant survival was high, radiotherapy proves to be a significant risk factor for implant loss. Augmentation procedures may also increase the risk of an adverse outcome, especially in combination with radiotherapy.