Faculty of Mechanical Engineering, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, Gliwice, Poland.
Department of Dental Technicians, Medical College of Silesian Province, Zabrze, Poland.
J Prosthodont. 2019 Jan;28(1):e27-e33. doi: 10.1111/jopr.12719. Epub 2017 Dec 29.
Tongue activity, involving stereognosis of denture position, food bolus distribution, and direct denture pressing, can affect the stability of removable mandibular dentures. Knowledge of details of tongue activity in patients with removable dentures could contribute to the development of training methods to improve bilateral mastication. The hypothesis of this study was that tongue force improves mandibular complete denture stabilization on the atrophied foundation during mastication load transfer with a typical balanced occlusion.
Finite element analysis was used to assess the effect of tongue activity on denture stability, which was evaluated with objective biomechanical criteria. Denture movement (displacement), sliding distance on the mucosal surface, and pressure on the foundation during occlusal load transfer were considered with and without additional tongue forces.
Tongue force in the canine zone of the balancing flange contributed to a slight reduction in the sliding distance. An adverse effect of tongue force on the working side and in the posterior zone of the balancing side was found.
Despite the lack of substantial improvement in stability with the addition of tongue forces, tongue action that contributes to a slight reduction in sliding may help reduce common frictional trauma resulting from cyclic movement during chewing. The beneficial impact of tongue force shown in earlier work under conditions of complete adherence of dentures to the foundation indicates a benefit of using adhesives.
舌体运动,包括义齿位置的实体觉、食物团块分布以及直接义齿压入,会影响可摘下颌义齿的稳定性。了解可摘义齿患者舌体运动的细节有助于开发提高双侧咀嚼的训练方法。本研究的假设是,在典型的平衡咬合中,舌力在咀嚼负荷传递过程中可改善下颌全口义齿在萎缩基托上的稳定性。
使用有限元分析来评估舌体活动对义齿稳定性的影响,用客观的生物力学标准来评估义齿稳定性。在有和没有额外舌力的情况下,考虑了在咬合负荷传递过程中义齿的移动(位移)、黏膜表面的滑动距离以及基托上的压力。
平衡翼的尖牙区的舌力有助于减少滑动距离。发现舌力对工作侧和平衡侧的后区有不利影响。
尽管增加舌力并不能显著提高稳定性,但有助于减少滑动的舌体运动可能有助于减少咀嚼过程中周期性运动导致的常见摩擦性创伤。在义齿完全贴合基托的情况下,早期工作中显示出的舌力的有益影响表明使用黏合剂有益。