The association between parafunctional oral habits and temporomandibular disorders development in childhood and adolescence: A systematic review and meta-analysis.

BACKGROUND

Temporomandibular disorders (TMDs) encompass conditions affecting the temporomandibular joints or masticatory muscles, impairing oral health-related quality of life. Parafunctional oral habits have been suggested to be associated with TMDs in children and adolescents.

TYPES OF STUDIES REVIEWED: Nine electronic databases were searched for observational studies evaluating parafunctional oral habits and TMDs in children and adolescents. Two reviewers independently selected studies, extracted data, and assessed risk of bias using Joanna Briggs Institute tools. Random-effects meta-analysis estimated odds ratios with 95% CIs, and certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

Thirty-five cross-sectional studies were included. Biting habits were associated with 45% higher odds of developing TMDs (odds ratio [OR], 1.45; 95% CI, 0.74 to 2.85; I2 = 95.9%), sucking habits with 33% (OR, 1.33; 95% CI, 0.84 to 2.09; I2 = 60.2%), and chewing habits with 84% (OR, 1.84; 95% CI, 1.09 to 3.11). Children with any parafunctional oral habit had a 2.16-fold higher odds of developing TMDs (OR, 2.16; 95% CI, 1.10 to 4.24; I2 = 70.0%). Results of the sensitivity analysis, after removing studies that used invalid diagnostic tools for TMD, showed that the data were not robust to changes in the effect estimates. Sixteen studies were analyzed narratively. The certainty of evidence was very low for all estimates.

CONCLUSIONS AND PRACTICAL IMPLICATIONS: The evidence does not support an association between parafunctional oral habits and TMDs in youth. Given the cross-sectional design of the included studies, no causal inferences can be established. The very low certainty indicates that the findings are uncertain. There is a need for high-quality longitudinal studies and validated assessment tools. This systematic review was preregistered in the International Prospective Register of Systematic Reviews (CRD42022385606).