Page 129 - Craniomaxillofacial Implant Surgery - Jeroen P.J. Dings

General discussion and future perspectives
Results from our study showed statistically significant higher survival rates for implants placed during ablative surgery compared to implants placed in a secondary procedure. In avoiding additional surgery and allowing uncomplicated osseointegration prior to possible postoperative radiation therapy, we advocate to insert implants immediately following ablative surgery. Furthermore, prosthetic rehabilitation of the CMF defect can be achieved earlier. In contrast, secondary placement implants may be beneficial, with regard to more specific patient assessment and implant placement39. However, a systematic review on the effects of pre- versus post-implantation irradiation therapy on dental implant failure could not establish a significant difference in survival rate40.
No beneficial effect of HBO therapy on osseointegration could be retrieved from our results. The evidence in literature on the use of hyperbaric oxygen therapy to improve osseointegration in irradiated patients remains controversial. A meta-analysis by Chrcanovic et al. (2016) revealed no statistically significant difference on implant survival in irradiated fields, with or without adjunctive HBO therapy33.
Hygiene is of utmost importance in preventing soft tissue infection35. Impaired hygiene may result from monocular vision, prosthetic abutments and bar attachments, or difficult access with regard to the nasal region resulting in impaired implant hygiene33. Chronic inflammation of peri-implant soft tissue inflammation can cause implant failure. Due to the retrospective design of this study and incomplete records no information could be retrieved with regard to the specific role of implant hygiene.
Furthermore, no distinct relation could be retrieved from our results, or is known in 7 literature, between survival rates of implants and variables as sex, age, type of implant
and prosthetic type34,36. Only Toso et al. found a higher survival rate for orbital implants
in female patients37. Furthermore, Toso et al. showed a statistically significant higher
survival rate for Branemark titanium implants (Nobel Biocare AB, Gothenburg, Sweden.) in comparison with Straumann EO implants (Institut Straumann AG, Waldenburg, Switzerland.). This difference is attributed to the smooth-machined titanium surface of the Branemark implants37.
In conclusion, this study showed a higher survival rate of nasal- and orbital implants placed during ablative surgery compared to implants placed in a later stage. It is, therefore, advocated by the authors to insert the CMF implants during the ablative surgical session. However, considering that the reported rates are subject to numerous
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