Coronal dentinal tubules of non-erupted deciduous incisors

Abstract

The diameter and density of coronal dentinal tubules were assessed in non-erupted human deciduous incisors. Using liquid nitrogen, frozen samples were fractured in longitudinal and oblique directions and observed by means of a Jeol JSM-6100 scanning electron microscope. It was observed that the diameter of dentinal tubules ranged from 0.50 to 1.94 micrometers and increased significantly from the outer to the inner layers. However, comparing the incisal, middle and cervical thirds, no statistically significant differences were observed. The number of tubules per square millimeter varied from 3,281 to 32,313 and also increased from the external dentinal surface to the dentinal surface of the pulp chamber.

Decreased dentin tubules density and reduced thickness of peritubular dentin in hyperbilirubinemia-related green teeth

“…Remarkably, the values found in the present study are similar to those previously described for normal human dentin both in permanent (20-23) and primary (24) anterior teeth; the number of tubules varied from 3.28 to 32.31 per square millimeter in such studies. Another study (25) compared tubule density between primary and permanent molars and suggested that tubule density was greater in primary molars (primary: 124.32/mm2 versus permanent: 45.97/mm2).…”

“…Another study analyzed the diameter of dentin tubules in primary molars and found that tubules’ diameters ranged from 0.96 to 1.29 µm, suggesting that different anatomic groups of teeth may present similar values for the diameter of the tubules (25). The findings of lack of altered diameter of dentin tubules in this study represent an interesting perspective for treatment of patients who developed hyperbilirubinemia in childhood because it is known that the diameter of dentin tubules influence dental adhesion, since they are related to dentinal permeability, and the smaller diameter may account for the lower permeability, that is because the efficacy of most of the current adhesives depends on the infiltration of the resin into the dentin (22,24). …”

“…The studies examining permanent (20-23) and primary (24) teeth observed values ranging from 0.50 to 1.94 µm. It was showed that comparing the incisal, middle and cervical thirds, no statistically significant differences were observed in relation to diameter of coronal dentinal tubules of non-erupted deciduous incisors (24), based on results as showed previous, this study only evaluated dentin tubules of cervical third, which presented dentin-tubules measures similar to findings of Costa et al , 2002 (24). Another study analyzed the diameter of dentin tubules in primary molars and found that tubules’ diameters ranged from 0.96 to 1.29 µm, suggesting that different anatomic groups of teeth may present similar values for the diameter of the tubules (25).…”

ImageJ analysis of dentin tubule distribution in human teeth

“…Detailed knowledge of the distribution and microstructure of dentin is essential for research and development because the efficacy of dental adhesion materials rely on infiltration into teeth; a reflection of dentin permeability (Costa et al, 2002;Lopes et al, 2009;Teixeira et al, 2009). Odontoblastic processes (or Tome's fibers) radiate toward the dentino-enamel junction of the anatomical crown or the cemento-dentinal junction of the anatomical root, together contributing to the cellular component of the dentin structure (Weiss, 1983;Young and Heath, 2000).…”

Structure and microstructure of coronary dentin in non-erupted human deciduous incisor teeth

“…The dentin of deciduous teeth revealed a thicker deciduous peritubular area compared to permanent teeth (3) and the presence of giant tubules, which are uncommon in permanent teeth (2,4,5). Deciduous dentin also had a smaller diameter and tubular density than permanent dentin and, consequently, less permeability (6)(7)(8)(9)(10). It is also reported that these aspects depend on the age of the tooth (11).…”