Cuiling Liu, Liyuan Yang, Zheng Zheng, Xu Gao
Dept. of Prosthodontics, Qilu Hospital, Shandong University, Jinan 250012, China.
Dept. of Prosthodontics, School of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Jinan 250012, China.
Hua Xi Kou Qiang Yi Xue Za Zhi. 2016 Oct 1;34(5):493-497. doi: 10.7518/hxkq.2016.05.012.
This study was performed to investigate the electromyographic (EMG) activity of the masseter muscle and the anterior temporalis muscle, as well as the masticatory efficiency after insertion of the dentures in edentulous individuals whose maxillomandibular horizontal relationship records were obtained with three different methods.
Ten edentulous individuals were enrolled in this study. Three types of complete dentures for these 10 edentulous patients were made according to their different maxillomandibular horizontal relationship records. The maxillomandibular horizontal relationship of complete dentures was recorded by three methods. In the first method (A), the maxillomandibular horizontal relationship was determined at the gothic arch tracing apex. In the second method (B), the relationship was 1 mm anterior to the tracing apex with the gothic arch. In the last method (C), the horizontal jaw relation was recorded by natural chewing. The muscular activities of the three complete dentures were examined by EMG. The masticatory efficiency was evaluated based on the absorbance. The differences among the dentures were statistically analyzed with SPSS 17.0.
The muscular activities of dentures B and C were much higher than that of denture A during clenching in the center occlusion and during chewing (P<0.05). The highest asymmetry index was found indenture C, which was significantly higher than those of dentures A and B (P<0.05). A statistically significant increase in the absorbance was observed between dentures B and C (P<0.05); otherwise, no statistically significant differences were observed (P>0.05) between B and C.
Given the limitations of this experimental design, in edentulous individuals the maxillomandibular horizontal relationship recorded at 1 mm anterior to the tracing apex with the gothic arch can improve the function of masticatory muscles and strengthen masticatory performance.
本研究旨在调查无牙颌患者采用三种不同方法记录上下颌水平关系后，义齿戴入后咬肌和颞肌前束的肌电活动以及咀嚼效率。
本研究纳入10名无牙颌患者。根据这10名无牙颌患者不同的上下颌水平关系记录制作三种类型的全口义齿。全口义齿的上下颌水平关系采用三种方法记录。第一种方法（A），在哥特式弓描记尖处确定上下颌水平关系。第二种方法（B），在哥特式弓描记尖前方1mm处确定关系。最后一种方法（C），通过自然咀嚼记录水平颌关系。采用肌电图检查三种全口义齿的肌肉活动。基于吸光度评估咀嚼效率。使用SPSS 17.0对义齿之间的差异进行统计学分析。
在正中咬合紧咬和咀嚼过程中，义齿B和C的肌肉活动明显高于义齿A（P<0.05）。义齿C的不对称指数最高，显著高于义齿A和B（P<0.05）。义齿B和C之间观察到吸光度有统计学意义的增加（P<0.05）；否则，B和C之间未观察到统计学意义的差异（P>0.05）。
鉴于本实验设计的局限性，在无牙颌患者中，在哥特式弓描记尖前方1mm处记录的上下颌水平关系可改善咀嚼肌功能并增强咀嚼性能。
