[Correlation between abnormal jaw movement dominated by the lateral pterygoid muscle and symptoms of temporomandibular joint disorder: a retrospective analysis].

Abstract

Objectives: To explore whether the difference in mandibular motor function related to the lateral pterygoid muscle is associated with pain and clicking in the temporomandibular joint based on clinical data.

Methods: Outpatient data from January 2022 to August 2025 were collected, and the basic information, joint symptoms, and diagnostic criteria for temporomandibular joint disorder (DC/TMD) of the patients were statistically analyzed. Patients were grouped according to their chief symptoms, and the chi-square test was used to explore whether the chief symptoms were correlated with age and gender. The Mann-Whitney U test was used to examine whether there were differences in lateral movement ability between different genders, and the Kruskal-Wallis H test was used to examine whether there were differences in lateral movement ability between different age groups. Patients were grouped according to whether they had pain, and the Mann-Whitney U test was used to examine whether pain was correlated with lateral movement ability. Binary logistic regression analysis was used to further explore the degree of correlation between joint pain and lateral movement imbalance. Patients were grouped according to different painful sides and relatively restricted sides, and the chi-square test was used to explore the correlation between the two. Multivariate logistic regression analysis was used to further explore the interaction between painful side and relatively restricted side.

Results: There was no statistically significant difference between the patient's age, gender, and main symptoms or lateral mobility; there was a statistical difference between the difference in lateral mobility and joint pain; there was a statistical difference between gender and mandibular protrusion ability; relative limitation on one side was a significant predictor of unilateral joint pain, but there was no specific side-specific combination association between the two; there was no statistical correlation between age, gender, and relative limitation on one side and bilateral joint pain.

Conclusions: Abnormal lateral movement has clinical significance in the early diagnosis of temporomandibular joint disorder. The gender-specific incidence of temporomandibular joint disorder may be related to the difference in forward movement ability. The bilateral muscle imbalance reflected by lateral movement imbalance should be taken seriously as a risk factor for joint pain.