Impacts of wearing complete dentures on bolus transport during feeding in elderly edentulous.

Prosthetic treatment with dentures is often required for the elderly who have reduced swallowing function. Therefore, it is important to understand the relationship between denture-wearing and feeding function from the perspective of swallowing. To clarify changes in bolus transport during feeding in elderly edentulous patients with or without complete dentures. Subjects were 15 elderly edentulous volunteers who were treated with maxillary and mandibular complete dentures. The test food was 10 g of minced agar jelly containing barium sulphate with a particle diameter of 4·0-5·6 mm. Lateral videofluoroscopy was performed to assess the position of the leading edge of the bolus, the bolus volume in each area at swallow onset, bolus transit time and the mandibular position during pharyngeal swallowing. There were significant changes between the bolus transport with and without dentures. Without dentures, the leading edge of the bolus at swallow onset fell from the valleculae area to the hypopharynx, and the bolus volume in the hypopharynx increased. Bolus transit time increased in the oral cavity, valleculae and hypopharynx. The mandibular position shifted anterosuperior direction. The results arose owing to anatomical changes in the oral and pharyngeal structure and the following functional changes: poor food manipulation, poor bolus formation and delayed swallowing reflex. Removing dentures in elderly edentulous individuals influences bolus transport during feeding, resulting in the exacerbation of the reduced swallowing reserve capacity that accompanies ageing, and may increase the risk of dysphagia.