Department of Oral and Maxillofacial Surgery and Pathology, University of Mississippi Medical Center, School of Dentistry, Jackson, MS, USA.
J Oral Rehabil. 2011 Jun;38(6):434-9. doi: 10.1111/j.1365-2842.2010.02169.x. Epub 2010 Nov 3.
This study tested the hypothesis that denture instability limits the amount of voluntary muscular effort generated by denture wearers. Seventeen edentulous subjects (seven men, 10 women; mean age 60·3 ± 13·0 years) with newly acquired implant-retained mandibular overdentures and a conventional maxillary denture participated. Maximum bite forces and corresponding electromyographic (EMG) activity from the temporalis and masseter muscles (bilaterally) were recorded under two experimental conditions: (i) Unilateral premolar and molar bites without additional support, and (ii) premolar and molar bites with bite block support on the opposite side. In addition, EMG values alone were recorded during maximum clenching without any transducer between the upper and lower dentures. The level of muscular effort was significantly higher with greater denture support. These results indicate that denture instability probably prevents denture wearers from using the full potential of their jaw muscles, especially during unilateral biting and chewing, even with two implants supporting the mandibular dentures.
本研究旨在验证以下假设，即义齿不稳定限制了义齿佩戴者自愿产生的肌肉力量。17 名无牙颌患者（7 名男性，10 名女性；平均年龄 60.3 ± 13.0 岁）参与了这项研究，他们均佩戴新制作的种植体支持的下颌覆盖义齿和传统的上颌全口义齿。在两种实验条件下记录了最大咬合力和来自颞肌和咀嚼肌（双侧）的相应肌电图（EMG）活动：（i）单侧前磨牙和磨牙咬合，无额外支撑，和（ii）对侧使用咬合块支撑的前磨牙和磨牙咬合。此外，还在上下义齿之间没有传感器的情况下单独记录了最大咬牙时的 EMG 值。更大的义齿支撑会显著提高肌肉用力水平。这些结果表明，义齿不稳定可能会阻止义齿佩戴者充分利用其颌部肌肉的潜力，尤其是在单侧咀嚼和咬合时，即使使用两个种植体来支撑下颌义齿也是如此。
