Is Cigarette Smoking a Risk Factor for Temporomandibular Joint Dysfunction?

Abstract

Objective: The relationship between cigarette smoking and temporomandibular joint disorders (TMJDs) is not fully
clarified. This study compared TMJD symptoms, mandibular functional impairment, and mouth-opening range
between smokers and non-smokers among university students.
Methods: In this comparative cross-sectional study, 132 university students (66 smokers, 66 non-smokers; ages 18–30)
were assessed. TMJD symptoms were measured with the Fonseca Anamnestic Index, mandibular function with the
Mandibular Function Impairment Questionnaire (MFIQ), and maximum mouth opening with a bicondylar caliper. Data
were analyzed using Mann–Whitney U tests; significance was set at p < 0.05.
Results: Smokers reported higher mean Fonseca scores than non-smokers (p < 0.05) and greater impairment on the
MFIQ functional-capacity (p < 0.05), nutrition (p < 0.05) and total MFIQ (p < 0.05) scores. No significant difference was
observed in maximum mouth opening (p > 0.05). TMJD severity categories showed higher proportions of moderate
and severe TMJD among smokers (p < 0.05).
Conclusions: Cigarette smoking was associated with increased TMJD symptom burden and functional impairment but
not with reduced maximal mouth opening. Clinicians should consider smoking status during TMJD assessment and
management. Longitudinal studies with objective tobacco exposure measures and imaging/functional diagnostics are
needed to establish causality and dose–response effects.