title: Dental age and dental health determined longitudinally from patient records in three towns in Finland.
abstract: The aims of this study were to test the suitability of normal dental records in determining the eruption times of teeth and to compare the retrospective longitudinal DMF values with the statistical cross-sectional means. Patient records for two cohorts (1970 and 1980) were collected from three Finnish towns. The study population comprised 1910 children. The eruption times of the permanent teeth, DMFT and DMFS curves (excluding F due to fractures and M due to orthodontic reasons) were investigated for the year of examination in different study locations. The cross-sectional DMF values were compared to longitudinally calculated data. Tooth eruption was earlier in girls than in boys. However, girls did not have significantly higher DMF values than boys. In all towns, dental health was significantly better in the 1980 cohort than in the 1970 cohort. Comparison of the cross-sectional DMF values in the municipal health center statistics showed that the mean statistics gave considerably higher values than the measured values did after 15 years of age. The inconsistency between measured longitudinal DMF values and the cross-sectional statistical DMF values indicates the importance of creating computer programs for analyzing data longitudinally from normal dental records.
authors.affiliation: Department of Pedodontics, Cariology and Endodontics, Institute of Dentistry, University of Oulu and Oulu University Hospital, Oulu, Finland. marjut.korhonen@oulu.fi
authors.forename: Marjut
authors.initials: M
authors.lastname: Korhonen
authors.forename: Markku
authors.initials: M
authors.lastname: Larmas
mesh_terms: D000293:Adolescent; D000366:Age Determination by Teeth; D000367:Age Factors; D000704:Analysis of Variance; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004245:DMF Index; D003731:Dental Caries / Q000453:epidemiology*; D003792:Dental Records; D005260:Female; D005387:Finland / Q000453:epidemiology; D005457:Fluoridation / Q000706:statistics & numerical data; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009909:Oral Health; D012189:Retrospective Studies; D012737:Sex Factors; D014078:Tooth Eruption