Prasanthi G S, Sajjan M C Suresh, Manikyamba Yenumula J B, Chandrasekhar P V B, Kotemsetty Sri Lakshmi
Department of Prosthodontics, Sibar Dental College, Guntur, Andhra Pradesh, India.
Department of Prosthodontics, Vishnu Dental College, Bhimavaram, Andhra Pradesh, India.
J Indian Prosthodont Soc. 2024 Oct 1;24(4):341-350. doi: 10.4103/jips.jips_51_24. Epub 2024 Oct 15.
This study aims to evaluate the changes in occlusal contacts resulting from variations in head postures (supine[S], semi-supine [SS], upright with head rest support [HR], and without head rest support [WHR]) after occlusal adjustment of conventional fixed dental prostheses using Tekscan III.
A cross-sectional study on 15 patients with missing single molars and undergone replacement with a fixed dental prosthesis.
Fifteen patients with a three-unit tooth-supported fixed dental prosthesis replacing a missing single posterior tooth were included. Tekscan III was used to analyze occlusion time (OT), disclusion time (DT), initial tooth contact, and relative bite force in different head postures by adjusting the backrest position before and after equilibration. Occlusal adjustments were performed to achieve the balance between the right and left halves.
The data were statistically analyzed using ANOVA and paired t-test.
Posterior shift of initial tooth contact was observed from SS to supine and upright positions, whereas an anterior shift occurred from SS to WHR support posture. High-intensity forces were observed before the occlusal adjustment in various head positions, and these forces changed after adjustments in SS position. However, medium-intensity force occlusal prematurities persisted in other head postures even after corrections in SS position. There was a significant difference in OT but not in DT in all head postures after equilibration. When OT was compared from SS to remaining posture after equilibration, the major difference was found from SS to head rest (HR) and supine to HR posture which infers the need for selective grinding in these postures.
Considering the various changes while changing the head position from the SS position to the other functional position, it can be inferred that there is a need to consider recalibration of occlusal contacts in all the functional postures.
本研究旨在评估使用Tekscan III对传统固定义齿进行咬合调整后，头部姿势（仰卧位[S]、半仰卧位[SS]、有头枕支撑的直立位[HR]和无头枕支撑的直立位[WHR]）变化导致的咬合接触变化。
对15例单颗磨牙缺失并接受固定义齿修复的患者进行横断面研究。
纳入15例用三单位牙支持式固定义齿修复单颗后牙缺失的患者。通过在调平衡前后调整靠背位置，使用Tekscan III分析不同头部姿势下的咬合时间（OT）、脱离接触时间（DT）、初始牙齿接触和相对咬合力。进行咬合调整以实现左右半侧之间的平衡。
数据采用方差分析和配对t检验进行统计学分析。
从SS位到仰卧位和直立位观察到初始牙齿接触向后移位，而从SS位到WHR支撑姿势则出现向前移位。在各种头部位置进行咬合调整前观察到高强度力，这些力在SS位调整后发生了变化。然而，即使在SS位进行校正后，中等强度力的咬合早接触在其他头部姿势中仍然存在。调平衡后所有头部姿势下OT有显著差异，但DT无显著差异。当比较调平衡后从SS位到其他姿势的OT时，主要差异存在于从SS位到有头枕（HR）位以及从仰卧位到HR位的姿势，这表明在这些姿势下需要进行选择性调磨。
考虑到从SS位改变至其他功能位时的各种变化，可以推断在所有功能位都需要考虑重新校准咬合接触。
