title: Applying modern survival analysis methods to longitudinal dental caries studies.
abstract: Before the 1960s, tooth-specific caries risk was reported to be highest at 2 to 4 years after eruption. We studied the tooth-specific caries risk in three contemporary age cohorts in Finland. All together, 4072 boys and girls were followed annually from age 6 to age 18+ years in three age cohorts born in the 1960s, 1970s, and 1980s. We used a survival model and Bayesian inferential methods in the statistical analyses to establish the secular changes during this period. The analysis was based on the caries risk in individual teeth as a function of tooth age instead of summary measures, such as DMFS values. Our first finding was a marked overall decrease of caries. Moreover, analyses of the 1960 and 1970 cohorts revealed that the risk in molar teeth was highest immediately after eruption; in the youngest cohort, however, the risks of individual teeth were so low that no such dependencies on tooth age could be established.
authors.affiliation: Rolf Nevanlinna Institute, University of Helsinki, Finland. Tommi.Harkanen@RNI.helsinki.fi
authors.forename: T
authors.initials: T
authors.lastname: Härkäne
authors.forename: M A
authors.initials: MA
authors.lastname: Larmas
authors.forename: J I
authors.initials: JI
authors.lastname: Virtanen
authors.forename: E
authors.initials: E
authors.lastname: Arjas
mesh_terms: D000293:Adolescent; D000465:Algorithms; D001499:Bayes Theorem; D002648:Child; D015331:Cohort Studies; D004245:DMF Index; D003731:Dental Caries / Q000209:etiology*; D003733:Dental Caries Susceptibility; D005260:Female; D005387:Finland; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D008297:Male; D008963:Molar / Q000473:pathology; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D014070:Tooth / Q000473:pathology*; D014078:Tooth Eruption