EMG correlations of edentulous patients with implant overdentures and fixed dental prostheses compared to conventional complete dentures and dentates: a systematic review and meta-analysis.

OBJECTIVES: The goal of this meta-analysis was to evaluate how muscular activity, measured by electromyography (EMG), differs among edentulous patients treated with a complete denture (CD), removable implant overdentures (IO), implant-retained fixed dental prostheses (IFDP), and dentates. The differences during clenching and chewing were of particular interest.

MATERIALS AND METHODS: An electronic literature review was carried out on MEDLINE (Pubmed) and the Cochrane Library covering the period January 1980 through September 2013. This was accomplished independently by three different reviewers and supplemented by a manual search. The review included randomized controlled trials, controlled clinical trials, and clinical trials which evaluated surface electromyography, bite force, chewing, and implants or complete dentures. In addition, the research was adjusted using MeSH terms.

RESULTS: The search garnered 646 titles and abstracts. Sixteen articles which met the inclusion criteria were analyzed. The effect size for muscular activity after implant support increased after therapy during clenching 2.18 (95% CI: 1.14, 3.23) and during chewing 1.45 (95%CI: 1.21, 1.69). Moreover, the EMG data of IO and IFDP groups (pooled) were lower than that of dentate control subjects during clenching (effect size: -1.01 [95%CI: -1.37, -0.65]). In contrast, the IFDP-wearers showed higher values than dentates during chewing. Among the edentulous control patients, the IO and IFDP groups (pooled) displayed higher values during clenching (effect size: 1.12 [95%CI: 0.7, 1.55]) and chewing (effect size: 1.33 [95%CI: -0.57, 2.10]). Furthermore, the muscular activity during chewing correlated with the hardness of the food.

CONCLUSION: In general, edentulous patients with CDs can achieve a greater degree of muscular activity after rehabilitation with IOs during clenching and chewing. During clenching, patients with IFDPs achieved higher values than those with dentates. The muscular activity increases with the hardness of the food.