Does the natural maxillary dentition influence the survival rate of mandibular metal-resin implant-supported fixed complete dentures? A systematic review and meta-analysis.

Statement Of Problem: Consensus is lacking regarding the influence of the maxillary dentition on the survival rate of a mandibular metal-resin implant-supported fixed complete denture (MRISFCD) with distal cantilevers.

Purpose: The purpose of this systematic review was to identify whether an opposing natural dentition influences the survival rate of mandibular MRISFCDs.

Material And Methods: A literature search was performed up to February 2018 from MEDLINE/PubMed, Scopus, Web of Science, Cochrane Library, BBO/LILACS databases and also in the non-peer-reviewed literature through Open Grey. Clinical studies regarding natural (ND), removable prostheses (RP), and complete fixed maxillary implant dentitions (ID) with at least a year of follow-up were included. The quality of the included studies was analyzed, and the risk of bias was reported. A meta-analysis comparing the survival rate of ND with RP and ND with ID was performed with a confidence interval (CI) of 95%, and heterogeneity was tested by an I index. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach was used to determine the certainty of the evidence.

Results: From a total of 112 ND, 69 ID, and 204 RP in the maxillary dentition, the overall prevalence of failures was 5.4% (6/112; 95% CI [2.3 to 10.76]) for ND, 13.99% (20/69; 95% CI [0.77 to 39.41]) for ID, and 4.9% (10/204; 95% CI [0.69 to 12.18]) for RP. No statistical differences were detected in the success rates between ND and RP (risk difference = 0.00 [-0.06, 0.06]; P=.93; I=27%) or between ND and ID (risk difference=0.00 [-0.06, 0.07]; P=.97; I=0%), both with moderate evidence.

Conclusion: With a moderate certainty of evidence, it is suggested that natural maxillary dentitions do not affect the survival rate of mandibular MRISFCDs differently from other prosthetic designs.