[DMF study on extracted deciduous teeth].

The aim of the present investigation was to study the number of the carious surfaces of extracted primary teeth in order to determine component m in the dmf-s index. Altogether 903 deciduous teeth were examined under artificial light with a dental probe. The surfaces were evaluated separately. The examined teeth were divided into two groups according to the amount of root resorption. On the basis of the present study the following conclusion can be drawn: 1. The average of df surfaces of molars was 2.34, whereas it was 0.74 at the front teeth. The df number shows practically only caries, because filled surfaces were found in only 1.99% of the cases. 2. In any type of the teeth df lesions were the rarest on the vestibular and oral surfaces. 3. Caries (filling) was found most frequently on the occlusal surfaces of the upper and lower 1st molars. Caries (filling was the rarest on the vestibular surfaces of the upper 1st and 2nd molars. 4. The amount of root resorption did not show much influence on the df score. 5. During the calculation of the dmf-s average of the primary teeth the m value can be substituted for 2.0.