Department of Social Dentistry, School of Dentistry of Araraquara, Universidade Estadual Paulista, Araraquara, São Paulo, Brazil.
Department of Basic and Oral Biology, School of Dentistry of Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil.
PeerJ. 2024 Apr 19;12:e17188. doi: 10.7717/peerj.17188. eCollection 2024.
This study aimed to assess the effects of different magnification systems on the angular deviations of the neck and trunk and the muscle activities of the upper back and neck during preclinical cavity preparation.
This was an experimental laboratory study, with the angular deviations from the neutral positions of the neck and trunk and the activities of the bilateral upper back (the descending and ascending trapezius) and neck (sternocleidomastoid) muscles as the dependent variables. The independent variables were the different magnification systems used (Simple, Galilean, and Keplerian loupes, with direct vision as the control) and prepared teeth (teeth 16, 26, 36, and 46). A dental mannequin phantom head with artificial resin teeth was used, and Class I cavity preparations for composite resin were performed on teeth 16, 26, 36, and 46 using a 1012 round diamond bur at low speed. To analyze the angular deviations, the postures adopted during the procedure were recorded using a tripod-mounted camera positioned to provide a lateral view of the operator. A trained researcher measured the angular deviations using the software entitled "Software for Postural Assessment"-SAPO (version 0.69). Bilateral muscle activity was assessed using surface electromyography. Descriptive statistical analysis was performed, and after verifying the assumptions of normality and homoscedasticity, two-way analysis of variance and the Tukey and Games-Howell post-hoc tests were used to compare the data (=0.05).
The angular deviation from the neutral position of the neck was found to be significantly higher during cavity preparations performed with the naked eye and the Simple loupe, irrespective of the prepared tooth. With regard to tooth location, the angular deviation of the neck was significantly greater during cavity preparation on teeth 16 and 26, and the angular deviation of the trunk was significantly greater during cavity preparation on tooth 26, regardless of the magnification system used. There were significant differences in right sternocleidomastoid muscle activity between the Simple, Galilean, and Keplerian loupes, with activity being the lowest for the Galilean loupe ( = 0.008). There were no significant differences in left sternocleidomastoid muscle activity between the loupes, regardless of the prepared tooth ( = 0.077). The activities of the bilateral descending trapezius and the right ascending trapezius muscles were significantly lower when the Galilean loupe was used ( < 0.010).
These results suggest that the Galilean loupe resulted in lower muscle activity in the neck and back regions and that the Galilean and Keplerian loupes resulted in less angular deviations of the neck and trunk during cavity preparation.
本研究旨在评估不同放大倍率系统对临床前牙体预备过程中颈部和躯干的角度偏差以及上背部和颈部肌肉活动的影响。
这是一项实验性实验室研究，以颈部和躯干从中立位置的角度偏差以及双侧上背部（下降和上升斜方肌）和颈部（胸锁乳突肌）肌肉的活动为因变量。自变量为使用的不同放大系统（简单、伽利略和开普勒体视显微镜，直接视觉为对照）和预备的牙齿（16、26、36 和 46 牙）。使用带有人造树脂牙齿的牙科仿人头模型，使用 1012 号圆形钻石车针以低速对 16、26、36 和 46 牙进行 I 类复合树脂窝洞预备。为了分析角度偏差，使用三脚架安装的相机记录程序中采用的姿势，该相机的位置提供了操作员的侧视图。一名经过培训的研究人员使用名为“姿势评估软件”-SAPO（版本 0.69）的软件测量角度偏差。使用表面肌电图评估双侧肌肉活动。进行描述性统计分析，在验证正态性和同方差性假设后，使用双向方差分析和 Tukey 和 Games-Howell 事后检验比较数据（=0.05）。
无论预备的牙齿如何，裸眼和简单体视显微镜进行牙体预备时，颈部从中立位置的角度偏差均显著更高。关于牙齿位置，无论使用何种放大系统，16 和 26 牙预备时颈部的角度偏差显著更大，26 牙预备时躯干的角度偏差显著更大。右胸锁乳突肌在简单、伽利略和开普勒体视显微镜之间的活动存在显著差异，伽利略体视显微镜的活动最低（=0.008）。无论预备的牙齿如何，体视显微镜之间的左侧胸锁乳突肌活动均无显著差异（=0.077）。使用伽利略体视显微镜时，双侧下降斜方肌和右侧上升斜方肌的活动显著降低（<0.010）。
这些结果表明，伽利略体视显微镜导致颈部和背部区域的肌肉活动降低，而伽利略和开普勒体视显微镜导致牙体预备过程中颈部和躯干的角度偏差更小。
