Introduction: A good understanding of the factors influencing craniofacial morphogenesis is essential for improved diagnosis and treatment of orthodontic anomalies. Our aim in this study was to investigate the correlations between muscular function and craniofacial morphology.

Materials and Methods: The study population consisted of a random sample of 102 volunteer young adults. Muscle function as demonstrated by the thickness of the masseter muscles was assessed in these subjects by real time ultrasonography using a linear 8 MHz probe. The craniofacial morphology parameters were calculated from lateral headfilms of each subject.

Results: There was no significant correlation between the variables in the sagittal dimension (SNA, SNB, ANB, AoBo) and the thickness of the masseters. In contrast, in the vertical dimension, the variables (ArGMe, SNPm, HFP) showed a significant correlation with masseter thickness.

Conclusion: The idea that craniofacial morphology can be influenced in part by the masticatory muscles could have useful implications for diagnosis and treatment of orthodontic dysmorphoses.