[The resistance to abrasion of dental materials]. / Zur Abrasionsfestigkeit zahnärztlicher Materialien.

Using a new method, the authors investigated the abrasion resistance of Kallocryl-A with regard to the kind of stress (abrasive or intermittent), the temperature, the depth of the layer of plastic and the number of abrasive movements. The results were analysed for significance by means of the t-test.

[Biodevelopmental and biostatistical aspects of the concept of normal values in the 1st and 2d dentition]. / Entwicklungsbiologische und biostatistische Aspekte des Normbegriffs bei der ersten und zweiten Dentition.

In conformity with the practice in other biological sciences, it is suggested to adopt in dentition chronology the double of the range around the mean as the range of normal. The great variance especially in the second dentition agrees with the variance of other developmental characteristics and must be considered to be typical of human development. The integration of dentition with the complex of the characteristics of physical and psychical development is advocated.