抄録
Mastication, deglutition, and respiratory movements were analyzed before and after application of topical anesthesia to the oral cavity to investigate the how sensation in the oral cavity affects swallowing and influences respiratory movement. Videofluorography was performed on 10 adult subjects using an X-ray TV system. Nasal respiratory dynamics were measured using a differential pressure flowmeter. The subjects were instructed to hold 10 mL of an oral topical anesthetic in their mouths for 5 minutes to paralyze oral sensation. Each subject freely chewed and swallowed 8 g of barium-containing corned beef as a test food. Videofluorographic images and respiratory flow waveforms were simultaneously recorded in a data recorder and analyzed on a computer. Because of the oral hypesthesia, the valleculae aggregation time (VAT) were significantly prolonged. Although VAT was less than one second before anesthesia, the time was prolonged after anesthesia in some subjects. The transport phase from the oral cavity to pharynx, starting from transport movement of the tongue to passage of the bolus tail through the posterior nasal spine, was significantly prolonged. The period from the start of hyoid bone elevation to breath-holding was significantly prolonged, showing that breath-holding for deglutition was delayed. These findings suggest that, in mastication-deglutition, oral sensation influences early movement including the occurrence of deglutition movement and breath-holding.
