title: [Investigation on the relationship of occlusal force to formation of wedge-shaped defects].
abstract: OBJECTIVE
  To clinically investigate and identify the occlusal force as one of factors relative to formation of wedge-shaped defects.
  
  
  METHODS
  123 subjects, selected from a group of middle-aged and elderly people in an urban area were divided into four groups: control, light, middle and severe group according to the severity of wedge-shaped defects. Cuspid, first and second premolars, and first molar in maxilla were examined for occlusal force by occlusometer, and the peak value of occlusal contact strain on every maxillary tooth was studied by photocclusion.
  
  
  RESULTS
  Significant reduce of occlusive force in the defected teeth was found than that of in the control teeth. The occlusal contact strain of first premolars with defects by photocclusion was statistically increased. The relative occlusal contact strain of first premolars and first molar of defects was higher than that of their proximate teeth.
  
  
  CONCLUSIONS
  Occlusal force could have relation to the formation of wedge-shaped defects.
authors.affiliation: Department of Operative Dentistry and Endodontics, Peking University School of Stamatology, Beijing 100081, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jiade
authors.initials: J
authors.lastname: Wang
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Zeng
authors.forename: Chunlian
authors.initials: C
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D001732:Bite Force; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014072:Tooth Abrasion / Q000209:etiology*