Caries in Dentin
Caries in Dentin
Generally
Since the critical pH value for dentin is higher than for enamel and it is also much more porous, Caries spreads much faster after reaching the dentin than in the Enamel.
Not to forget : Critical pH for: Enamel: 5.2-5,7 Dentin: 6,2-6,7 ¹
From the Outside to the Inside²’³
1. Zone of Necrosis
Dentin is softened and liquefied (necrotic), vital and dead microorganisms and their enzymes are found.
2. Zone of Penetration
Penetration of mainly gram-positive bacteria (lactobacilli) into the dentin canals - rupturing of the tubules (ampoule-shaped) in the area of the growth lines fissile. If there are several ampoules among themselves, one speaks of rosary figures.
3. Zone of Demineralization
In the light microscopic image unchanged, but with bite wing imaging especially in the approximal area to diagnose. Demineralization can come to a halt by eliminating the carriogenic noxes and can be partially remineralized.
4. Zone of Dead Tracts
because of tooth decay, the odontoblastic processes in the dentin tubules have decreased to the cell body. In severe cases, the cells themselves can die. Zone in which odontoblast processes no longer exist. Higher permeability than in normal dentin.
5. Sclerotic dentin
Sclerotic or transparent dentin contains dentin tubules, which are completely obliterated by deposit of peritubulary dentin. Peritubulary dentin and mineralization of odontoblast processes.
6. Tertiary dentin
Cariogenic stimuli induce the formation of irritant at the pulp-dentin limit.
References
- Marsh PD, Lewis MAO, Rogers H, et al. Oral Microbiology. 6th ed. 2016; Edinburgh: Churchill Livingstone Elsevier.
- Oral Histology Digital Lab: Dentin: Sclerotic Dentin (Image 37). http://www.uky.edu/~brmacp/oralhist/module5/lab/imgshtml/image37.htm; Accessed on Oct 20, 2019
- Schroeder, H.E.: Pathobiology of oral structures.
Karger-Verlag, Basel, 1983; Pages 65-80.