Effect of complete denture wearing on tongue motor biomechanics during swallowing in edentulous older adults

Aim: Contact of the tongue against the hard palate plays an important role in swallowing. Therefore, age-related decline in tongue function has received much attention. The purpose of the present study was to investigate the effect of complete denture wearing on tongue motor biomechanics during swallowing in healthy edentulous older adults. Methods: A total of 19 edentulous patients (6 males and 13 females, mean age 76.2 +/- 7.2 years) without any history of neuromuscular disease or dysphagia were selected. All patients were wearing complete dentures in both the upper and lower jaws. Tongue pressure against the hard palate during swallowing saliva was recorded using an original T-shaped sensor sheet with five measuring points. Measurements were carried out both with and without the prostheses. For evaluating swallowing ability, the frequency of swallowing saliva in 30 s was recorded (Repetitive Saliva Swallowing Test). Results: With the prostheses, the maximal magnitude and duration of tongue pressure was larger at Ch. 1 (anterior-median part of the hard palate) and Ch. 2 (mid-median part) right and left circumferential parts than without the prostheses. As for the integral of tongue pressure, that with prostheses was larger at all 5 channels than that without prostheses. There was significant improvement in the Repetitive Saliva Swallowing Test value while wearing prostheses. Conclusions: These results suggested that swallowing function deteriorated as a result of the decline in tongue-palate contact on removing complete dentures in edentulous older adults. Clinical relevance: The present study showed the effect of wearing prostheses on swallowing in edentulous older adults.