Purpose: To verify the occurrence and associate the presence and duration of harmful oral habits with the structures and functions of the stomatognathic system.
Methods: This is a cross-sectional, exploratory study. Participants' participation was formalized by the signing of an Informed Consent Form. The non-probabilistic sample comprised 289 children aged one to 12 years assisted at a Family Health Strategy unit. The data were obtained through a questionnaire to identify harmful oral habits applied to the children's parents and/or guardians. The results were considered at 5% level of significance. The statistical analyses were performed using the SPSS 19.0 software and the chi-squared association test was employed to investigate the categorical variables.
Results: The breastfeeding rate found was 85%; however, only 32.4% of the children were exclusively breastfed until six months of age. The most prevalent habits and those currently maintained were use of conventional bottle (28.62%) and conventional pacifier (23.18%). Significant correlation (p=0.001) was found between keeping the mouth open and oral and oronasal breathing. The presence of habits such as using orthodontic bottle (p=0.016) and orthodontic pacifier (p=0.001) was associated with the breathing mode reported. Habit duration was associated with the perception of changes in speech (p=0.046) and with malocclusion (p=0.014).
Conclusion: The presence and duration of harmful oral habits were associated with the perception of changes in the structures and functions of the stomatognathic system regarding occlusion, breathing, and speech, accounting for a significant portion of the demand for rehabilitation.