Association of Temporomandibular disorders with Malocclusion Complexity using Index of Complexity, Outcome and Need (ICON): A Case-Control study

Abstract

Objective: Our study’s objective was to investigate the association between temporomandibular disorders (TMDs) and complexity of the patient’s malocclusion utilizing Index of Complexity, Outcome, and Need (ICON).

Materials and Methods: This case-control observational study was carried out at the Department of Orthodontics, Dental College HITEC-IMS, Taxila from September 2024 till February 2025. A total of 300 participants aged 18-35 years were included in this study. Out of 300, 150 individuals were included into the case group (diagnosed with TMD using the Fonseca questionnaire) while 150 individuals were included in the control group (without TMD). Malocclusion complexity was assessed using ICON. Comparison of TMD and ICON grades were done using chi-square test while logistic regression was used to assess the association of TMD with the complexity of patient’s malocclusion.

Results: The mean age of the patient was 25.14 ± 4.72 years. Out of 300 participants, females constituted 61.3% while males constituted 38.7% of the sample. A significant association was observed between higher ICON grades and TMD (p=0.001). The results of logistic regression indicated that individuals with “difficult” or “very difficult” ICON grades had higher odds of developing TMD (OR=1.206). No significant association was found between TMD and gender (p=0.947).

Conclusion: Malocclusion complexity is significantly associated with TMD, with higher ICON grades correlating with an increased risk of TMD. These findings highlight the importance of evaluating malocclusion in TMD diagnosis and management.