Most implant studies deal only with local risk factors, although the existence of systemic risk factors plays a significant role to the implant survival. We use the NobelActive dental implant in this study in order to investigate if this promising implant with the special design could achieve better survival rates in difficult situations with several risk factors. The present study revealed no statistically significant difference in the survival rate of implants between patients with systemic RFs and healthy controls. The only statistically significant difference concerned implants of patients with both systemic and local RFs (p = 0.006).

Despite the heterogeneity of the studies, it appears that diabetes (both types) [22, 23] is related to delayed wound healing [24], alterations in early bone healing due to poor glycemic control [25], and marginal bone loss [26, 27]. Moreover, greater failure rates were found in patients who had diabetes for longer time periods [28]. Other studies, however, did not find a difference in survival rates between diabetics and healthy patients [29, 30].

Our study included a patient after resection of an Ewing sarcoma in the left maxilla who was treated with dental implants 2 years after the hemimaxillectomy and 1 year after the completion of the combined radiochemotherapy in order to achieve an oral rehabilitation. 3 months after the insertion of six implants; four of them should be removed because of lack of osseointegration. At the moment of the implant placement as well as at the moment of the implant removals, there was no recurrence of the sarcoma. Studies comparing patients that had undergone radiation treatments and non-irradiated controls have found similarly ambiguous results [31]. Ihde et al. [32] exhibited a two to three times greater failure rate in irradiated bone compared to non-irradiated. Curi et al. showed that mode of radiation therapy delivery (p = 0.005) had a statistically significant influence on implant survival [33].