Association Between Tooth Eruption and Parent-Reported Awake Bruxism in Early Childhood

Mandibular instability during primary tooth eruption has been suggested as a factor associated with parent-reported awake bruxism (PRAB) in early childhood, but this relationship remains unclear.

To evaluate the association between PRAB frequency and the number of erupted primary teeth by dental groups, as well as signs and symptoms of tooth eruption, oral habits, and sociodemographic characteristics.

This cross-sectional study included 144 Brazilian children aged 4-36 months. Parents/caregivers completed an interview-based questionnaire covering sociodemographic characteristics, oral habits, signs and symptoms of tooth eruption, and PRAB frequency. A single-trained dentist performed oral examinations to record erupted primary teeth. Descriptive analysis, chi-square, and Kruskal-Wallis tests were conducted (p < 0.05).

The prevalence of PRAB was 16.7%. No significant association was found between PRAB frequency and sex, age, oral habits, or signs and symptoms of tooth eruption. However, more erupted primary molars (p = 0.038) and canines (p = 0.022) were associated with a lower PRAB frequency.

The number of erupted primary molars and canines was associated with the frequency of PRAB in early childhood, supporting the hypothesis that AB during this stage may represent an adaptive behaviour.