The Effect of Temporomandibular Joint Disc Displacement Type on Jaw Function Limitation

Abstract

Aim: Temporomandibular joint disorder (TMD) present symptoms such as pain, swelling, clicking or crepitating sounds, limitations or blockages in jaw movements, and may even affect simple functions such as eating and speaking. This study aims to evaluate the impact of disc displacement type on jaw function in patients with TMD who suffer from disc displacement. Material and Methods: This cohort study was conducted on patients with temporomandibular joint (TMJ) disc displacement. The independent variable was the type of disc displacement. The outcome variable was the scores on the Jaw Functional Limitation Scale-20 (JFLS-20). The covariates included the patient's age and pain score. Data collection methods were carried out using the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) guidelines and the JFLS-20 questionnaire, with pain levels also assessed using a visual analog scale. Data analysis was performed using ANOVA and Pearson Correlation tests, with a significance level set at 0.05. Results: The study groups were formed by including 72 patients with disc displacement, while the control group was formed by including 28 healthy volunteers. The control group had lower JFLS-20 scores than the disc displacement groups(p<0.05). Although there was no statistically significant difference in JLFS-20 scores between the disc displacement groups, disc displacement with reduction group had significantly lower pain scores than both disc displacement without reduction groups(p<0.05). Conclusion: It was observed that individuals with disc displacement experience restricted jaw functions, and this limitation is not affected differently by the various subtypes of disc displacement.