title: Jaw muscles in older overdenture patients.
abstract: OBJECTIVE
  To determine, using computer tomography (CT), whether the retention of a small number of teeth in the older adult used to support overdentures could affect the cross-sectional area (CSA) and X-ray density of two jaw closing muscles.
  
  
  METHODS
  Cross-sectional study of a group of older patients subdivided into dentate, edentulous and those wearing overdentures supported by two to five teeth.
  
  
  METHODS
  The sample consisted of 24 subjects aged 55-68 years.
  
  
  METHODS
  CSA and X-ray density of two jaw closing muscles, masseter and medial pterygoid were measured and evaluated using CT.
  
  
  RESULTS
  There were no significant differences between left and right jaw muscles, but the CSA of the masseter muscles were significantly larger than the medial pterygoid muscles. The CSA of the masseter and medial pterygoid muscles was significantly smaller in edentulous subjects compared with dentate subjects but no significant difference was observed between subjects wearing overdentures and those with a natural dentition. No significant differences were observed with the X-ray density between different muscles or dental states.
  
  
  CONCLUSIONS
  The retention of a small number of teeth in the older adult used to support overdentures appears to sustain the CSA of two jaw closing muscles and therefore could enhance these patients' masticatory ability compared with those who were edentulous.
authors.affiliation: Oral Physiology Research Group, The Dental School, University of Dundee, Dundee, UK. j.p.newton@dundee.ac.uk
authors.forename: James P
authors.initials: JP
authors.lastname: Newton
authors.forename: Frank C
authors.initials: FC
authors.lastname: McManus
authors.forename: Stephen
authors.initials: S
authors.lastname: Menhenick
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D019412:Anatomy, Cross-Sectional; D002508:Cephalometry; D003430:Cross-Sectional Studies; D003817:Dentition; D003828:Denture, Overlay; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000000981:diagnostic imaging; D008297:Male; D008406:Masseter Muscle / Q000000981:diagnostic imaging*; D016555:Matched-Pair Analysis; D008875:Middle Aged; D009066:Mouth, Edentulous / Q000000981:diagnostic imaging; D011626:Pterygoid Muscles / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed