[The incidence of hypodontia with the presence and absence of wisdom teeth]. / Häufigkeit der Zahnunterzahl bei Anlage und Nichtanlage von Weisheitszähnen.

Radiographs of 2550 orthodontic patients were evaluated for tooth agenesia dependent on the presence and the missing of third molars. Tooth agenesia (except third molars) was found in 248 patients (9.7%). The missing of third molars occurs at 427 of 2061 patients (20.7%) aged between 12 and 36 years. At 81.5% of all patients with tooth agenesia at least one of the third molars was missing. The rate of agenesia had an amount of 5.9% (97 of 1634 patients) in the group of patients with presence of all third molars. Whereas the rate of agenesia at patients with missing of one or more third molars was with 27.6% especially great. Moreover it was found out, that the rate of agenesia was the greater the more third molars were missing.

[Revision of the "prognosis of supporting structures in the second dentition" after Trankmann and Raufmann]. / Uberprüfung der "Prognose der Stützzonen im Gebiss der zweiten Dentition."

A prognose of the support zone of the permanent dentition, introduced by Tränkmann and Raufmann in 1983, has been investigated. The results of the investigations confirm fundamentally the correlations set up by the authors. It is pointed at restrictions in connection with the reliability of these method of prognose.