The Effect of Reading Aloud Exercises for Complete Denture Patients during the Functional Rehabilitation Period

A Systematic Review and Meta-analysis of the Effect of Oral Exercises on Masticatory Function

The aim of the current systematic review was to summarize and to evaluate the available information on the effectiveness of oral exercise in improving the masticatory function of people ≥18 y. Electronic databases (Medline, Embase, CENTRAL) and gray literatures were searched (up to December 2020) for relevant randomized and nonrandomized controlled clinical trials. Two reviewers independently conducted the study selection, data extraction, and quality assessments. Meta-analysis was conducted for the comparison of bite force and masticatory performance using mean difference (MD) and standardized mean difference (SMD), respectively. GRADE (Grading of Recommendations Assessment, Development, and Evaluation) assessment was adopted for collective grading of the overall body of evidence. Of the 1,576 records identified, 18 studies (21 articles) were included in the analysis. Results of meta-analysis indicated that oral exercise could significantly improve the mean bite force of the participants (parallel comparison: MD, 41.2; 95% CI, 11.6-70.7, P = 0.006; longitudinal comparison: MD, 126.5; 95% CI, 105.2-144.9, P < 0.001). However, the improvement in masticatory performance was not significant (parallel comparison: SMD, 0.11; 95% CI, -0.20 to 0.42, P = 0.48; longitudinal comparison: SMD, 0.4; 95% CI, -0.11 to 0.91, P = 0.13). Results of meta-regression showed that greater improvements in bite force can be achieved among younger adults and with more intensive exercise. Chewing exercise is the most effective oral exercise, followed by clenching exercise, while simple oral exercise may not have a significant effect. Based on the results of the meta-analysis and GRADE assessment, a weak recommendation for people with declined masticatory function to practice oral exercise is made.

Relevance of Tongue Force on Mandibular Denture Stabilization during Mastication

PURPOSE

Tongue activity, involving stereognosis of denture position, food bolus distribution, and direct denture pressing, can affect the stability of removable mandibular dentures. Knowledge of details of tongue activity in patients with removable dentures could contribute to the development of training methods to improve bilateral mastication. The hypothesis of this study was that tongue force improves mandibular complete denture stabilization on the atrophied foundation during mastication load transfer with a typical balanced occlusion.

MATERIALS AND METHODS

Finite element analysis was used to assess the effect of tongue activity on denture stability, which was evaluated with objective biomechanical criteria. Denture movement (displacement), sliding distance on the mucosal surface, and pressure on the foundation during occlusal load transfer were considered with and without additional tongue forces.

RESULTS

Tongue force in the canine zone of the balancing flange contributed to a slight reduction in the sliding distance. An adverse effect of tongue force on the working side and in the posterior zone of the balancing side was found.

CONCLUSIONS

Despite the lack of substantial improvement in stability with the addition of tongue forces, tongue action that contributes to a slight reduction in sliding may help reduce common frictional trauma resulting from cyclic movement during chewing. The beneficial impact of tongue force shown in earlier work under conditions of complete adherence of dentures to the foundation indicates a benefit of using adhesives.