title: Health gain from restorative dental treatment evaluated by computer simulation.
abstract: OBJECTIVE
  To simulate the influence over time of relevant factors on health gain from restorative dental treatment under varying assumptions and to compare outcomes with those resulting under a 'do nothing' scenario.
  
  
  METHODS
  A decision model was used in a computer simulation of the caries process in posterior approximal tooth surfaces. The effect of superimposing restorative treatment, based on bitewing radiology, was incorporated. Input data came from current observational studies and included caries progression rates, notional survival times of restorations, and sensitivity (Sn) and specificity (Sp) of treatment decision making by a high (A) and a low (B) performing dentist. Utility values, on a scale 0-1, for different tooth health states were obtained from questioning 92 adults of appropriate age.
  
  
  METHODS
  By assumption, the primary dental care sector.
  
  
  METHODS
  A hypothetical population, initially 14-15 years old.
  
  
  METHODS
  Class II amalgam restorations.
  
  
  RESULTS
  Computed in utility based units (UBUs) as sums of the product of numbers of sound, carious and restored surfaces and their utility values. Health gain (in UBUs) was assessed relative to interim end point UBUs pertaining under 'do nothing'.
  
  
  RESULTS
  One thousand approximal surfaces, designated initially as 920 sound, 51 carious and 29 filled were followed in the model over 10 years. The greatest health gain (33.16 UBUs) was from dentist A (Sn = 0.23, Sp = 0.99, 50 per cent restoration survival rate = 10 years, caries rate = 4.4% per annum). The least was from dentist B (Sn = 0.52, Sp = 0.88, 50% survival = 5 years, caries rate = 0.0% per annum) representing a loss of 17.07 UBUs compared with 'do nothing'.
  
  
  CONCLUSIONS
  Results suggest that caution is advisable when making positive decisions to restore on the basis of bitewing radiographs.
authors.affiliation: National Centre for Transcultural Oral Health, Eastman Dental Institute for Oral Health Care Sciences, London, UK.
authors.forename: M C
authors.initials: MC
authors.lastname: Downer
authors.forename: D R
authors.initials: DR
authors.lastname: Moles
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D003198:Computer Simulation; D003657:Decision Making; D003661:Decision Support Techniques; D003723:Dental Amalgam; D003731:Dental Caries / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy; D003793:Dental Restoration, Permanent / Q000145:classification; D018450:Disease Progression; D005069:Evaluation Studies as Topic; D005500:Follow-Up Studies; D006801:Humans; D008954:Models, Biological; D009909:Oral Health; D017063:Outcome Assessment, Health Care; D016300:Radiography, Bitewing; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016019:Survival Analysis
chemical_list: D003723:Dental Amalgam