ABSTRACT
The objective of this systematic review was to determine the effect on oral health-related outcomes from mandibular implant-retained dentures opposing maxillary complete dentures in edentulous middle-age and older adults, compared with complete removable dentures in both arches. Randomized controlled trials included participants with an average age of 65 years or older. The Cochrane Library, MEDLINE, and Web of Science were searched. A total of 228 abstracts were reviewed for inclusion criteria, with 14 trials included and analyzed for risk of bias. Eleven of these studies were assessed as being at an unclear risk of bias, and 3 were at high risk. Mandibular implant-retained overdenture therapy showed statistically significant improvements in the patients' general satisfaction ( P = .003), oral health-related quality of life ( P < .001), and chewing ability ( P < .001), over the patients with complete dentures. There were no significant differences in the percentage of patients who were satisfied with their overdentures vs complete dentures for comfort, retention, esthetics, or chewing ability; however, only 2 studies reported these outcomes. In terms of nutritional status 1 year after treatment, vitamin B12 blood levels increased significantly in the implant-retained group ( P = .003), but not the other nutritional values. Implant-retained mandibular overdentures are an option for middle-aged and elderly edentulous patients as they significantly improve some of the outcomes; however, the quality of the evidence was moderate/low, due to the small number of studies included and the risk of bias. Future research should include objective outcomes such as masticatory performance, chewing efficacy, and muscular coordination.