Implant‐supported cantilevered fixed dental rehabilitations in fully edentulous patients: Systematic review of the literature. Part II

Abstract

The first use of dental implant was documented in restorations of fully edentulous patients. These reconstructions were provided in both jaws and consisted in 4-6 implants supporting a complete fixed prosthesis. Implants were often placed only in intra-foramina area or in the anterior maxilla. The restorations were then mainly delivered with bilateral cantilevers (Adell, Hansson, Brånemark, & Breine, 1970;Brånemark et al., 1969). The use of implant-supported restorations with cantilevers has been documented over time. Studies have analysed this type of restoration and assessing the survival rate of restorations and implants as well as the rate and type of complications. The rational of the use of cantilevers in fully edentulous patients is the possibility of providing full-arch reconstructions by placing implants in more anterior areas, thus avoiding resorbed or low quality bone regions. More evidence has been published (Heydecke, et al., 2012) reporting that the use of only four or six implants could be sufficient to support a full-arch restoration: whether the last implant should be placed underneath the last tooth or not is still in debate. The positioning of an implant in posterior areas may often require more complex procedure, such as bone augmentations procedures, Abstract Aim: To investigate fully edentulous patients rehabilitated with cantilever-fixed implant-supported restorations and to analyse which complications are reported for this type of treatment. MaterialsandMethods: Two operators screened the literature (MEDLINE, EMBASE) and performed a hand search on the main journals dealing with implantology and prosthetics until 31 December 2017. Only articles that considered cantilever implantfixed restorations with at least 10 patients and with a mean follow-up of at least 5 years were selected. The outcome variables were survival of implants and prosthesis, mechanical, technical and biological complications, marginal bone loss. The review was performed according to the PRISMA statements. The risk of bias was evaluated for each article. Failure and complication rates were analysed using random effect Poisson regression models to obtain summary estimate of 5-and 10-year survival and complication rates.Results: Fourteen papers for fully edentulous patients were selected. The estimated 5 to 10 years survival rate was calculated to be 99.00% and 96.7% for the implants and the prosthesis, respectively. A total of 299 complications (technical and biological) were reported with a cumulative 5-10 years complication rate of 44.41% and 39.46% for the patients and for the prosthesis, respectively. Conclusions:There is evidence that cantilever can be successful treatment in fully edentulous patients.

Biomechanical aspects: Summary and consensus statements of group 4. The 5th EAO Consensus Conference 2018

“…High prosthesis survival rates (98%) were reported for multiunit fixed reconstructions exhibiting cantilevers (Storelli, Del Fabbro, Palandrani, & Romeo, 2018). The survival rate of the implants supporting these prostheses amounted to 98%.…”

Occlusal overload with dental implants: a review

“…Another implant prosthetic design that has been assumed to cause occlusal overload is the cantilever prosthesis. However, systematic reviews and meta-analyses as well as long-term follow-up studies of cantilevers in the partially edentulous patients have demonstrated similar marginal bone levels as the fixed dental prostheses without a cantilever [48–53]. This is irrespective of the use of a mesial or distal cantilever [54].…”

Principles of biomechanics in oral implantology

“…This does not mean that cantilevers are not recommended. On the contrary, several studies present their advantages [28][29][30] but restate the importance of understanding and respecting the biomechanical implications. The length of the cantilever and its potential harmful effects is also dependent on the number of implants.…”