OBJECTIVE:To assess the occurrence of bruxism in deciduous dentition and a potential
association between the habit and the presence or absence of posterior crossbite.
METHODS: A total of 940 patient files were assessed. They were gathered from the archives
of University of São Paulo City - UNICID; however, 67 patient files were dismissed
for not meeting the inclusion criteria. Therefore, 873 children, males and
females, comprised the study sample. They were aged between 2-6 years old and came
from six different public primary schools from the east of the city of São Paulo.
Data were collected through questionnaires answered by parents/guardians and by
clinical examinations carried out in the school environment in order to obtain the
occlusal characteristics in the transverse direction. First, a descriptive
statistical analysis of all variables was performed (age, sex, race, posterior
crossbite, bruxism, headache and restless sleep); then, the samples were tested by
means of chi-square test with significance level set at 0.05%. A logistic
regression model was applied to identify the presence of bruxism. RESULTS: The prevalence of this parafunctional habit was of 28.8%, with 84.5% of patients
showing no posterior crossbite. Regarding the association of bruxism with
crossbite, significant results were not found. Children with restless sleep have
2.1 times more chances of developing bruxism, whereas children with headache have
1.5 more chances. CONCLUSION: Transverse plane of occlusion was not associated with the habit of bruxism.