[Changes in the epidemiological profile of dentofacial anomalies and in the status of orthodontic treatment between 1979 and 1989 in the city and district of Leipzig (an ICS-I replication study). International Study of Dental Manpower System].

Ten years after the Leipzig ICS-I-Study a replication study was performed in analogous fashion and in the same territory. Using the COCSTOC methods changes in the prevalence of dental-facial anomalies and the orthodontic state of treatment were determined in a random sample of 13-14-year-old school children. The prevalence of anomalies had decreased within a decade from 43% to 35%. At the same time the percentage of children not under treatment decreased from 14% to 10%. The causes are seen mainly in the area under consideration and the related preservation of the support zone until the physiological replacement of teeth as well as a reduced extraction rate for primary and permanent teeth.