Evaluation of canonical correlations between masticatory muscle orientation and craniodentofacial morphology in 10-17 year-olds

  • Vahid Zand Endodondist, Dental and Periodontal Research Center, Dental School, Tabriz University of Medical Sciences, Tabriz-Iran.
  • Morteza Oshagh Orthodontist, Private Practice
  • Nariman Iraji Nasrabadi Dentist, Tehran, Iran.
  • Parvin Kharazi Orthodontist, Private Practice
  • Fatemeh Bahramnia
Keywords: correlations, craniodentofacial, morphology, masticatory muscles


Objectives Different theories have been suggested to define factors involved in skeletal and craniofacial morphology. Many of these
theories explain that the bone morphology is the result of the bone tissue capability to adapt in response to biomechanical forces exerted
during growth. Also, it seems logical to hypothesize that there is a relationship between biomechanical connections of muscles to bones
with the morphology of musculodentoskeletofacial complex. A few studies have evaluated muscle orientation in different skeletal
occlusions (class I, II and III). The aim of this study was to evaluate correlations between masticatory muscle orientation and craniodentofacial
morphology in different skeletal malocclusions.
Materials and Methods A total of 160 lateral cephalograms of patients between 10–17 years in a dental clinic were evaluated for the
orientation of masticatory muscles and craniofacial morphology. All cephalograms were traced and confirmed by an orthodontist. Thirtyseven
parameters (skeletal, dental, muscular) were measured. For statistical analysis, canonical correlation, variation and linear regression
analysis were performed.
Results Increase of the masseter muscle angulation was accompanied by a more superior position of the muscle in female subjects with
Class II malocclusion. Increase of temporalis muscle angulation was seen in long face males. Increase of the masseter muscle angulation
and its higher position were seen in short face males.