A COMPARATIVE-STUDY OF TRANSLUCENT APICAL DENTIN IN VITAL AND NONVITAL HUMAN TEETH

Previous studies have shown that dentinal apical translucency increase s with age. Although the mechanism by which apical translucency is pro duced is still uncertain, it has been suggested that it develops at a slower rate in non-vital teeth. In this investigation the amount and d istribution of apical : translucent dentine in a group of age-matched vital and non-vital teeth were compared. Fifty-five non-vital (root-fi lled) teeth and 49 vital teeth were used. Freshly extracted teeth were fixed in 2% glutaraldehyde solution, sectioned longitudinally in the buccolingual plane and ground to a thickness of 150 mu m. Each section was photographed in polarized light at a standard magnification again st a ruled scale background. Black-and-white prints of standard magnif ication were produced and translucent apical dentine was plotted using an Apple II digitizer. Variables measured were length, length as a pe rcentage of root length, area and area as a percentage of root area. D ata were related to age and tooth type and analysed by Mann-Whitney an d regression analysis. Significant differences (p < 0.05) were present when tooth types were pooled. There was more apical translucency pres ent in all types of non-vital teeth when compared with vital teeth at any given age.