Comprehensive in Vitro Analysis of Masticatory Muscle Activity During Orthodontic Treatment with Clear Aligners: A Detailed Electromyographic (EMG) Simulation Study

Abstract

Background: Clear aligners are a popular orthodontic treatment option due to their aesthetic appeal and comfort. However, the impact of clear aligners on masticatory muscle activity remains underexplored. Understanding these effects is crucial for optimizing treatment outcomes and ensuring patient comfort.

Objective: This in vitro study aimed to evaluate masticatory muscle activity during orthodontic treatment with clear aligners using advanced electromyographic (EMG) simulation techniques.

Materials and Methods: Thirty artificial mandibular models, produced using 3D printing from biocompatible resin, were used. These models were mounted on a mechanical setup to simulate masticatory functions. Clear aligners were fitted according to standardized protocols. Surface EMG electrodes were placed on the masseter, temporalis, and lateral pterygoid muscles. EMG data were recorded before and after aligner application and after 2 weeks of simulated treatment. Data were analyzed using root mean square (RMS) values and statistical tests, including paired t-tests and ANOVA. Machine learning models, such as Support Vector Machines (SVM) and Convolutional Neural Networks (CNN), were employed for pattern recognition.

Results: Significant increases in muscle activity were observed for the masseter (21.7%), temporalis (22.6%), and lateral pterygoid (16.1%) muscles following aligner application (p < 0.05). Custom aligners showed higher RMS values compared to standard aligners. CNN achieved 95.8% accuracy, and SVM achieved 92.3% accuracy in predicting muscle activity changes. ANOVA confirmed significant effects of aligner types on muscle activity.

Conclusion: The study highlights significant changes in masticatory muscle activity associated with clear aligners. Advanced EMG techniques and machine learning models provided detailed insights, underscoring the need to consider muscle activity in orthodontic treatment planning.