The prevalence of posterior crossbite, deep bite, and sleep or awake bruxism in temporomandibular disorder (TMD) patients compared to a non-TMD population: A retrospective study.

Objective : To assess the prevalence of posterior crossbite and/or deep bite among patients diagnosed with temporomandibular disorders (TMD) compared to a non-TMD population. Methods : Four hundred ninety-four patients were enrolled: 345 with TMD according to the diagnostic criteria for TMD and 149 without TMD (control group). The chi-square test was used for statistical analysis. Results : A statistically significant association was found between sleep and awake bruxism and painful TMDs ( p < .001 for both), but not with disc displacement. There was no association between posterior crossbite and/or deep bite with either painful TMD or disc displacement. Conclusion : Within the study limitations, sleep bruxism and awake bruxism may be related to pain in the TMD, and the severity of a deep overbite and presence of a unilateral or bilateral posterior crossbite should not be considered risk factors or as having any effect on the pain associated with TMD and/or disc displacement.