Abstract
This study evaluated the relationship between maxillofacial morphology, volume of masseter muscle and inclination of masseter muscle in mandibular prognathism patients with those having normal occlusion.
The subjects consisted of 10 mandibular prognathism patients (mean: 21.6 years old) and 25 male (mean: 27.5 years old) with normal occlusion. The maxillofacial morphology was observed by lateral cephalograms. The volume and inclination of masseter muscle were determined from MRI images.
There was no significant difference in volume of masseter muscle between mandibular prognathism patients and those with normal occlusion. In mandibular prognathism patients, the volume of masseter muscle was not correlated with any items, but the inclination of masseter muscle was correlated with SNB, ANB, FH-palatal plane, Gonial angle, Ramus inclination, Y axis, and Saddle angle. In patients with normal occlusion, the inclination of masseter muscle was correlated with Ramus inclination, and the volume of masseter muscle was correlated with FMA, MP-palatal plane, SN-GoGn, Gonial angle, and Saddle angle. These results suggest that the inclination of masseter muscle is correlated with mecisodistal development.
