OBJECTIVE: Understanding the effects of biological aging on @entity1 tissues has been a topic of extensive research. With the increase in healthy seniors and quality of life that topic is becoming increasingly important. In this investigation the effects of aging on the microstructure, chemical composition and @entity3358 of @entity1 coronal dentin was studied from a comparison of teeth within "young" and "old" age groups. METHODS: The microstructure of dentin within three regions (i.e., inner, middle and outer) was analyzed using electron and optical microscopy. The mineral-to-collagen ratio in these three regions was estimated using Raman spectroscopy and the @entity3358 was evaluated using microindentation. RESULTS: Results showed that there were significant differences in tubule density, tubule diameter and peritubular cuff diameter with depth. Although there was no difference in tubule density and diameter of the tubules between the age groups, there was a significant difference in the occlusion ratio. A significant increase in @entity3358 between young and old @entity1 was found for middle and outer dentin. An increase in mineral-to-collagen ratio from inner to outer dentin was also found for both groups. In old @entity1 , an increase in mineral content was found in outer coronal dentin as a consequence of tubule occlusion. CONCLUSIONS: An increase in occlusion ratio, @entity3358 , and mineral content was found in the dentin of adult @entity1 with age. This increase is most evident in the outer coronal dentin.

Effect of aging on the microstructure, XXXX and chemical composition of dentin.

@entity1 :: ('9606', 'Species') :: ['human', 'patients'] @entity3358 :: ('MESH:D018804', 'Disease') :: ['hardness']
@entity3358 :: (MESH:D018804,Disease) :: ['hardness']
