Objectives

The buccinator (BUC) is an important muscle for oral function. Since it lies deep in the facial skin, recording its activity is difficult; thus, studies on its function are limited. We developed a method to access the deep facial muscles from the mucosal side. The aim of this study was to test the reliability of the new recording method for the BUC and to investigate the BUC behavior in typical facial functions.

Methods

To evaluate the new method, BUC activities were recorded simultaneously with a gel-type electrode on the skin and the newly developed surface electrode on the buccal mucosa. Electromyographic (EMG) activities in function, such as chewing and swallowing, along with the activities of the lower orbicularis oris (OO), zygomaticus major, masseter, and digastric muscles, were compared using the two recording methods. EMG activities among various tasks were compared using normalized values based on those obtained during maximum lip closure (MaxLC).

Results

The new surface electrode was made of gold plates on a thin plastic fixed to a stainless-steel wire frame and weighed less than 1 g. The BUC activity recorded from the mucosa was the highest during a corner-pulling task and was low during clenching. The BUC was active during MaxLC, similar to the OO, and the BUC activity pattern among tasks recorded from the mucosa was identical to that reported by previous studies using intramuscular electrodes. The new electrode evaluated the BUC activities quantitatively, and the recordings by the new electrode were free from contamination.

Conclusions

The findings of this study confirmed the reliability of the new BUC recording method. It could be easily placed correctly within seconds, without the need for cleansing or sterilizing the skin. The BUC and OO were active during a MaxLC task, indicating that the BUC assists lip closure by pulling the corners of the mouth. The basic facial functions evaluated, including chewing, were similar to those studied by intramuscular electrodes.

中文翻译：

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从粘膜表面记录琥珀酸化酶功能活性模式的新方法

目标

鼓泡器（BUC）是口腔功能的重要肌肉。由于它位于面部皮肤深处，因此很难记录其活动。因此，对其功能的研究是有限的。我们开发了一种从粘膜侧进入深部面部肌肉的方法。这项研究的目的是测试BUC的新记录方法的可靠性，并研究典型面部功能中BUC的行为。

方法

为了评估该新方法，同时记录了BUC活性，皮肤上的凝胶型电极和颊粘膜上的新开发的表面电极。使用两种记录方法比较了功能性肌电图（EMG）的活动（例如咀嚼和吞咽）以及下轮齿（Obicularis oris）（OO），大zy肌，咬肌和腓肠肌的活动。使用基于最大唇闭合（MaxLC）期间获得的归一化值，比较各个任务之间的EMG活动。

结果

新的表面电极由固定在不锈钢线框上的薄塑料上的金板制成，重量不到1 g。从粘膜记录的BUC活性在拔角任务中最高，而在紧握过程中则低。BUC在MaxLC期间是活动的，类似于OO，并且从粘膜记录的任务中的BUC活性模式与以前使用肌内电极的研究报道的相同。新电极定量评估了BUC活性，新电极的记录无污染。

结论

这项研究的结果证实了新的BUC记录方法的可靠性。它可以轻松地在几秒钟内正确放置，而无需清洁或消毒皮肤。BUC和OO在MaxLC任务期间处于活动状态，表明BUC通过拉动嘴角来辅助唇部闭合。评估的基本面部功能（包括咀嚼）与肌内电极研究的相似。