How Does the Use of an Intraoral Scanner Affect Muscle Fatigue? A Preliminary In Vivo Study

Abstract

The purpose of this study was to evaluate muscle activation and fatigue in the operator during tooth preparation and intraoral scanning by simulating these tasks in two types of dental unit chair systems (UCS). Six participants were recruited, and the above tasks were simulated. Electrodes were placed on the skin over five types of muscles (arm, neck, and shoulder muscles), and the maximal voluntary contraction (MVC) was measured. Electromyography (EMG) was assessed during the simulation, and EMG values were normalized using MVC. The root mean square (RMS) EMG (%MVC) and muscle fatigue (%) were calculated. Owing to a lack of normal distribution of the data, Mann–Whitney U test and Kruskal–Wallis H test were performed for statistical comparison, and Bonferroni adjustment was performed for multiple comparisons (α = 0.05). There was no significant difference in RMS EMG between the two types of dental UCS (intraoral scanning, p = 0.237; tooth preparation, p = 0.543). Moreover, the RMS EMG and muscle fatigue were not significantly different between the two tasks (p > 0.05). There was significant muscle fatigue after the intraoral scanner use was simulated thrice (p < 0.001). It is necessary to refrain from performing continuous intraoral scanning and tooth preparation and to take appropriate rest to reduce the incidence of musculoskeletal disorders in dentists in clinical settings.

Prediction of learning curves of wired and wireless intraoral scanners

“…A previous study reported that repeated use of IOSs could affect muscle fatigue 8 . This is one of the heaviest devices among medical devices used directly in the oral cavity, and the weight of IOSs ranged from 113 to 585 g 8 .…”

“…A previous study reported that repeated use of IOSs could affect muscle fatigue 8 . This is one of the heaviest devices among medical devices used directly in the oral cavity, and the weight of IOSs ranged from 113 to 585 g 8 . In the present study, a survey was conducted after the experiment, and 79% of the participants preferred wired IOSs (Fig.…”

“…Specifically, the chairside dental CAD/CAM process has been established for intraoral scanners (IOSs) 4 – 7 . Moreover, owing to the rapid development of IOSs, it has become possible to manufacture an accurate fixed dental prosthesis that that is at par with the prosthesis manufactured by conventional manufacturing methods 8 – 11 . For the optimal clinical application of IOSs in dentistry, the effects of temperature 9 , ambient light 10 , and narrow and deep area scans on the oral cavity 11 were evaluated.…”

Advances in Biomechanics-Based Motion Analysis

“…He et al [ 15 ] investigated how Schroth exercises, one of the commonly used training methods for patients with adolescent idiopathic scoliosis in clinical settings, activate the paraspinal muscles in concave and convex sides; the findings provide evidence for the effectiveness of this treatment. Son et al [ 16 ] analyzed the sEMG signals of neck, shoulder, and arm muscles during dentists’ daily occupational tasks, and found that the repetition of one task causes muscle fatigue, a finding which supports the importance of rest for reducing occupation-related musculoskeletal disorders. By examining elbow flexor sEMG signals in patients after spinal cord injuries (SCIs) vs. healthy controls, Li et al [ 17 ] found that both the muscle fiber conduction velocity (indicating muscle properties) and the sEMG–force relationship (indicating central neural drive) had been altered after SCI.…”

Quantitative assessment of muscle fatigue during rowing ergometer exercise using wavelet analysis of surface electromyography (sEMG)

“…Electromyography (EMG) is a method of measuring electrical signals generated in skeletal muscles to quantitatively assess muscle fatigue or exertional force ( Hou et al, 2021 ; Son et al, 2022 ). Quantitative assessment of muscle fatigue using surface electromyography (sEMG) has been the subject of numerous studies ( Zhang et al, 2019 ; Yun et al, 2020a ; Yun et al, 2020b ) leading to the need to develop electromyographic models that can correlate changes in sEMG signals with muscle fatigue ( González-Izal et al, 2012 ).…”