Articles
ASSOCIATION BETWEEN THYROID HORMONE INTAKE AND TEMPOROMANDIBULAR DISORDER: A CROSSSECTIONAL STUDY
PURPOSE. Temporomandibular disorder (TMD) consists of multifactorial pathologies of the temporomandibular joint and its surrounding structures. Thyroid hormones affect metabolism, growth, contractile function, and regeneration of muscles. The aim of this cross-sectional study was to investigate the association between intake of a thyroid hormone drug (levothyroxine) and TMD in an adult population.
MATERIALS AND METHODS. Adult patients referred to University of Florence for a dental visit were included in the present study. During the first appointment, personal, medical history and clinical data were recorded, and thyroid hormone drug (levothyroxine) regimen noted. Fonseca Anamnestic Index was used to classify patients as with or without TMD, and the resulting data was then subjected to logistic regression analysis.
RESULTS. Of a total of 1212 patients included, 124 (10.2%) were taking levothyroxine and 271 (22.4%) suffering from at least mild TMD. Seventy-eight (6.4% of the total sample) were classified as having severe TMD, while the remaining 941 (77.6%) had no history of TMD. The data collected indicates that TMD is more frequent in young, female, non-smoking patients using levothyroxine (OR = 2.64 95% CI from 1.74 to 4.00; P <0.0001). Severe TMD was more frequent in young female patients, in whom, however, the association with levothyroxine intake was not significant (OR=0.53 95% CI from 0.15 to 1.56 P=0.2531).
CONCLUSIONS. Levothyroxine intake, as well as the age and sex of the patient, is correlated with the presence of TMD.