title: Retrospective long term monitoring of tooth wear using study models.
abstract: OBJECTIVE
  Tooth wear is recognised as a common feature of European dentitions. However, little is known about its progression in susceptible patients. The aim of this study was to assess the degree and progression of tooth wear in patients by examining study casts taken of their teeth on two separate occasions.
  
  
  METHODS
  Over 500 sets of study casts taken during an 18-year period from patients referred for a variety of restorative procedures, were examined at Guy's Dental Hospital. Of these, 34 cases were found to have consecutive models taken at two time intervals and these were used to assess the progression of tooth wear. Study models from 19 females and 16 males, with an average age of 26 years (range 18-60) at the time of their first presentation and were all examined by a single operator. The Smith and Knight tooth wear index was used to assess the degree of tooth wear at presentation and then at another time which was a median of 26 months (interquartile range 14 - 50 months) later.
  
  
  RESULTS
  The most common initial TWI score per surface was 1, with 54% of surfaces affected at the first assessment and 57% at the second. Score 2 was less common (14% at both assessments) and the scores for 3 and 4 combined were relatively uncommon with 5% of surfaces effected. Minimal progression of tooth wear was observed on study casts with only 7.3% of surfaces involved.
  
  
  CONCLUSIONS
  In this sample, tooth wear was a slow, minimally progressive process.
authors.affiliation: Division of Conservative Dentistry, Guy's, King's and St Thomas' Dental Institute, King's College, London. david.bartlett@kcl.ac.uk
authors.forename: D W
authors.initials: DW
authors.lastname: Bartlett
mesh_terms: D000293:Adolescent; D000328:Adult; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D003765:Models, Dental; D012189:Retrospective Studies; D019217:Tooth Attrition / Q000473:pathology*; D014077:Tooth Erosion / Q000473:pathology*