title: Iatrogenic damage to approximal surfaces in contact with Class II restorations.
abstract: OBJECTIVE
  This study investigated the frequency of iatrogenic damage to approximal surfaces in contact with Class II restorations.
  
  
  METHODS
  Patients (n = 28) with a Class II restoration in contact with an unrestored surface had elastic separators fitted interproximally. Contralateral (unrestored) control surfaces were also separated. Impressions (light body polyvinylsiloxane) of the separated surfaces were taken 3-6 days later. Interproximal impressions (28 paired, seven unpaired) were examined by binocular microscope and scanning electron microscope (SEM) for iatrogenic damage, attrition and cavitation due to caries.
  
  
  RESULTS
  49-60% of surfaces adjacent to Class II restorations had been iatrogenically damaged. The most frequent types of damage were vertical grooves (26%), extensive damage (17%), indentations (6%) and scratches (6%). Damage was more frequent in maxillary teeth (61%) than mandibular teeth (25%), in permanent teeth (60%) more than deciduous teeth (20%). Qualified dentists produced more iatrogenic damage (64%) than undergraduate students (23%).
  
  
  CONCLUSIONS
  The frequency of iatrogenic damage to approximal surfaces following Class II preparations was 49%, and possibly as much as 60% when questionably damaged surfaces were included. Protection of the adjacent enamel is of paramount importance during Class II cavity preparation.
authors.affiliation: Department of Paediatric Dentistry, Eastman Dental Institute and Hospital, London, UK. veruska@england.com
authors.forename: V A
authors.initials: VA
authors.lastname: Medeiros
authors.forename: R P
authors.initials: RP
authors.lastname: Seddon
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003761:Dental Impression Technique; D003793:Dental Restoration, Permanent / Q000009:adverse effects* / Q000145:classification; D005260:Female; D006801:Humans; D007049:Iatrogenic Disease / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D012189:Retrospective Studies; D013499:Surface Properties; D018677:Tooth Injuries / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*