Relationship between eating/swallowing function and respiration mode in children with habit-forming mouth breathing

本研究旨在探讨儿童习惯性口呼吸对咀嚼及姿势的影响。初步研究对象为5名健康成人，模拟鼻塞模拟鼻塞。采用表面电极技术，对咬肌、眼轮匝肌、狭锁乳突肌和喉周围肌进行肌电检测。用机电换能器测得呼吸曲线。肌电与呼吸曲线同步。在休息和咀嚼酸奶或饼干时，检查鼻塞的影响。获得了以下结果。鼻塞下呼吸周期紊乱，吞咽前后呼吸周期延长，吞咽后即刻呼吸曲线波幅降低。与以往的研究结果一样，在鼻塞的情况下咀嚼频率降低。而咬肌肌电的周期、间期、时程则因受试者不同而呈现不同的模式。认为在模拟鼻塞条件下发生了基于获得性自身正常功能的代偿效应，选择有口呼吸的儿童使用CO2传感器试剂盒。受试者在吃饼干时评估呼吸方式，记录嘴唇姿势和咀嚼频率。用带有鼻塞的二氧化碳传感器试剂盒测量PaCO2是一种方便、实用的呼吸模式评估方法。习惯口气组儿童在吃饼干时，口闭率较低，呼吸节律紊乱，PaCO2曲线移动不规律。在休息时张开嘴，但在适应症下可以通过鼻子呼吸的儿童在吃饼干时表现出有规律的呼吸。关于进食/吞咽功能与口腔呼吸的协同作用还需要进一步研究。

The purpose of this study is to investigate how habit-forming mouth breathing in children influences on mastication and posture.The subjects of preliminary study were five healthy adults under the condition of nose obstruction simulated by pinching the nose. Electromyograms (EMG) were obtained from masseter muscle, orbicularis orbis muscle, stenocleidomastoid muscle, and muscles around larynx using a surface electrode technique. Respiratory curves were obtained with amechano-electrical transducer for respiration. The EMGs and respiratory curve were synchronized. The effects of nose obstruction were examined during resting and masticating yogurt or cookie. Following results were obtained. Under the nose obstruction, disorder of respiration cycles, prolonged respiration cycle before and after swallowing, decrease of amplitude of respiration curve just after swallowing. As the results in previous studies, frequency of mastication decreased under the nose obstruction. The other hand, cycle, interval, duration of EMG of the masseter muscle showed various patters depend on the subjects. It was thought that compensatory effects based on acquired own normal function were occurred under the simulated nose obstruction.Children with oral breathing were elected using CO2 sensor kit. The subjects were evaluated respiration mode and recorded posture of lips and frequency of mastication during eating cookie. Measuring PaCO2 by the CO2 sensor kit with nasal adapter was convenient and useful method for evaluating respiration mode. The children classified into habit-forming mouth breather showed quite low rate of mouth closure, disorder of respiration rhythm, and irregular movement of PaCO2 curve during eating cookie. The children who held mouth open at rest but could breathe through the nose under indication showed regular respiration during eating cookie. Further study regarding eating/swallowing function in cooperation with respiration in mouth breathers is needed.