Satoda Takahiro, Shimoe Saiji, Makihira Seicho, Tamamoto Mitsuhiro, Murayama Takeshi, Nikawa Hiroki
Department of Oral Health Engineering, School of Oral Health Science, Faculty of Dentistry, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553, Japan.
Kaibogaku Zasshi. 2008 Jun;83(2):51-7.
It is difficult to teach students about the mechanism of swallowing. There are three phases of swallowing; oral phase, pharyngeal phase and esophageal phase. The bolus of food is propelled to back of mouth by the tongue and the swallowing reflex happens. After nasopharynx and mouth closure, the glottal closure occurs, then hyoid and larynx are lifted by the contractions of suprahyoid and thyrohyoid muscles. As for the epiglottis, it is compressed by the tongue and inclines downward. As the larynx is lifted upward and anteriorly, slight vacuum is caused in the lower pharynx and upper esophagus at the same time, and pharyngeal constrictor compress bolus, therefore, the bolus passes the piriform fossa, and is inhaled into the esophagus. This time, we made a model in order to explain this complicated mechanism. The mandible is made of paper clay by using a metallic plate in it. The tongue, the soft palate, and the epiglottis are made by using the EVA (Ethylene Vinyl Acetate) sheet. Styloglossus, suprahyoid, thyrohyoid muscles are made with the wire. Moreover, a movable wooden chip represents the contraction of the pharyngeal constrictor muscles. The spring is put in the trachea in order to lift the larynx. The upper part of esophageal constrictor is made with spring plates.
向学生讲授吞咽机制是很困难的。吞咽有三个阶段：口腔期、咽期和食管期。食物团被舌头推到口腔后部，吞咽反射发生。鼻咽和口腔闭合后，声门关闭，然后舌骨和喉部被舌骨上肌群和甲状舌骨肌的收缩抬起。至于会厌，它被舌头挤压并向下倾斜。当喉部向上向前抬起时，下咽和上食管同时会产生轻微的负压，咽缩肌挤压食物团，因此，食物团通过梨状窝，被吸入食管。这次，我们制作了一个模型来解释这个复杂的机制。下颌骨用含金属板的纸黏土制成。舌头、软腭与会厌用乙烯-醋酸乙烯共聚物（EVA）片材制成。茎突舌肌、舌骨上肌群、甲状舌骨肌用金属丝制成。此外，一个可移动的木片代表咽缩肌的收缩。弹簧置于气管内以抬起喉部。食管括约肌的上部用弹簧板制成。
