title: Correlation between the lateral pterygoid muscle attachment type and temporomandibular joint disc position in magnetic resonance imaging.
abstract: OBJECTIVE
  The aim of this study was to investigate the correlation between the lateral pterygoid muscle (LPM) attachment type and temporomandibular joint (TMJ) disc position on sagittal and coronal MR scans.
  
  
  METHODS
  191 patients (148 females, 43 males), aged 14-60 years, underwent MR investigations of the TMJs in the intercuspal position (IP) and open-mouth position (OMP). The disc position was evaluated on oblique sagittal and coronal images in the IP and OMP on many MRI sections showing all portions of the joint. Relationships between the LPM attachment patterns and articular disc positions were evaluated by z and χ2tests.
  
  
  RESULTS
  Three types of the LPM attachment were found. There was a statistically significant correlation between the LPM attachment type and the disc position in IP (χ2= 24.29; p < 0.01). The type of muscle attachment did not determine the prevalence of normal, lateral and medial disc positions. There were differences between the muscle attachment types in the anterior, anteromedial and anterolateral disc positions. There was a statistically significant association between TMJ disc position in OMP and particular attachment types in the sagittal plane (χ2= 9.702; p < 0.01).
  
  
  CONCLUSIONS
  Certain types of the LPM insertion are correlated with TMJ disc position.
authors: 1 Department of Functional Masticatory Disorders, Medical University of Lublin, Lublin, Poland.
authors: Monika
authors: M
authors: Litko
authors: 1 Department of Functional Masticatory Disorders, Medical University of Lublin, Lublin, Poland.
authors: Jacek
authors: J
authors: Szkutnik
authors: 1 Department of Functional Masticatory Disorders, Medical University of Lublin, Lublin, Poland.
authors: Marcin
authors: M
authors: Berger
authors: 2 Independent Unit of Propedeutics of Dentomaxillofacial Radiology, Medical University of Lublin, Lublin, Poland.
authors: Ingrid
authors: I
authors: Różyło-Kalinowska
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011626:Pterygoid Muscles / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D019224:Temporomandibular Joint Disc / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D055815:Young Adult
keywords: MRI; pterygoid muscles; temporomandibular joint disc; temporomandibular joint disorders