Implant prognosis in irradiated versus non-irradiated nasal, orbital and auricular sites.

The purpose of this systematic review was to evaluate implant survival in irradiated nasal, auricular, orbital sites and to compare them with non-irradiated respective sites. Four electronic databases and seven related journals were searched until December and March 2018, respectively. A total of 7892 articles were identified, 18 of which were included in this review; one non-randomized clinical trial, two prospective cohort, eight retrospective cohort and seven cross-sectional studies. Using the ROBIN-I Cochrane tool for risk assessment, 13 studies were judged at serious, one at moderate and four at critical risk of bias. Thirteen were included in 18 meta-analyses, the results of which showed a significant difference between irradiated and non-irradiated sites, favouring non-irradiated with risk ratio (RR) = 0.93, 95% confidence interval (CI) 0.89-0.97, P=0.001. Comparisons among nasal, auricular and orbital sites revealed no significant differences, whether in irradiated or non-irradiated patients at P<0.05. Hence, it was concluded that, within the limitations of this review, survival of craniofacial implants is negatively affected by radiotherapy, especially in orbital sites. Level of evidence is moderate. Therefore, further prospective cohort studies with calculated sample sizes, restricted or properly managed confounders and no deviations from intended interventions might produce different results.