Bjørndal L, Thylstrup A. A comparative histologic study of the pulpdentinal interfxe in undemineralized and demineralized tooth sections. Acta Odontol Scand 1994;52:198-202. Oslo. ISSN 0001-6357This study examines cellular differences between undemineralized and demineralized tooth sections. The material comprised unerupted and partly erupted third molars. After fixation for 24 h, 10to 15-μm ground sections were prepared from half of the tooth, using a cutting-grinding system. The sections were compared with demineralized routine sections from the other half of the tooth. Undemineralized sections showed a better capacity for preserving the tissue integration. Especially between the odontoblast layer and the predentin a low frequency of disjunctions or tears were noted. At this level of examination fixation quality and vacuole frequency (intra-cellular spaces) did not show any differences between the two methods.