Influence of masseter muscle thickness on buccal corridor space and craniofacial morphology: A correlative study

Purpose: The present study was designed to evaluate the influence of masseter muscle thickness on buccal corridor space and underlying craniofacial morphology. Materials and Methods: Forty-six young adults (23 males and 23 females) in the age group of 18–23 years having intact dentitions and Class I molar relationship were included in the study. Masseter muscle thickness was measured using ultrasonography in relaxed, smiling, and contracted states. Posed smile photographs were taken to measure the buccal corridor space. Standardized frontal and lateral cephalograms were taken to determine craniofacial morphology in all three dimensions. Results: The mean masseter muscle thickness was 10.54 (±1.92) mm, 12.00 (±2.06) mm, and 14.04 (±1.99) mm in relaxed, smiling, and contracted states, respectively. Statistically significant correlation also was noted between masseter muscle thickness, during contracted state and buccal corridor width ratio. There was a strong association of masseter muscle thickness on both vertical as well as transverse craniofacial morphologies. Conclusions: Masseter muscle thickness is positively correlated with the buccal corridor width and influences both vertical as well as transverse facial dimensions.