The fibrillar structure of the cemento-dentinal junction in different kinds of human teeth

The cemento-dentinal junction was examined in human maxillary incisors, can ines and premolars by scanning electron microscopy combined with NaOH macer ation. The NaOH maceration was used to remove interfibrillar substances and to observe details of the fibrillar architecture. The teeth were half-sect ioned longitudinally, demineralized and macerated for 3-4 days or for 10-14 days. In the 3-4 day-macerated specimens, longitudinal sections of the cem ento-dentinal junction were examined. In the 10-14 day-macerated specimens, the cementum was detached and the inner cementum surface facing the cement o-dentinal junction was examined. Observations suggested that cemental fibr ils intermingle with dentinal fibrils only in places at the cemento-dentina l junction in both acellular and cellular cementum. These structural featur es were consistent in all kinds of teeth investigated here. Using human mol ars, we have previously proposed that the adhesion of proteoglycans is a ma in factor for the cemento-dentinal attachment and that the fibril interming ling between dentin and cementum is an accessory or secondary factor. The p resent study suggests that this applies to other kinds of human teeth.