title: Radiographic recognition and distribution of approximal carious lesions in New Zealand undergraduate dental students.
abstract: Bitewing radiographs are widely used to detect caries on the approximal surfaces of teeth. The aim of this study was to determine the prevalence of approximal caries in an educated young adult (New Zealand dental student) population, and to compare the diagnostic decisions of students and university teachers. A total of 123 students aged from 18 to 25 years (mean age 21 years) participated, having given their informed consent. Their bitewings were digitised and assessed for approximal carious lesions from the distal surface of the first premolars to the mesial surface of the second molars on the same computer screen. The following criteria were used: (0) no detectable radiolucency, (R1) lesion confined to the outer half of the enamel, (R2) lesion into the inner half of the enamel, (R3) lesion into the outer half of dentine along the amelodentinal junction, (R4) lesion beyond the outer part of the dentine. The views were assessed by two final-year dental students and two experienced university teachers, and results were compared. A total of 2710 surfaces were examined; restored and missing surfaces (tooth absent, off film or surface unreadable) were excluded. Carious lesions were found in 173 (6.38 percent) of the surfaces. Only 57 subjects presented with carious lesions radiographically, but 16 (13 percent) of subjects had 87 percent of all the lesions. Seventy-nine percent of the lesions were enamel lesions (R1 and R2), with 21 percent of the lesions having dentine involvement (R3 and R4). Inter-examiner agreement was high, Pearson's correlation coefficient r = 0.8237, and Cohen's kappa kappa = 0.76.
authors.affiliation: Department of Oral Rehabilitation, School of Dentistry, University of Otago, Dunedin. nick.chandler@dent.otago.ac.nz
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: Chandler
authors.forename: Betty P
authors.initials: BP
authors.lastname: Ng
authors.forename: Brian D
authors.initials: BD
authors.lastname: Monteith
mesh_terms: D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D003731:Dental Caries / Q000000981:diagnostic imaging / Q000453:epidemiology*; D006801:Humans; D009520:New Zealand / Q000453:epidemiology; D015588:Observer Variation; D015995:Prevalence; D011859:Radiography; D013335:Students, Dental / Q000706:statistics & numerical data*