Dentine permeability increases:
- a- Coronal less than root dentine.
- b- Permeability increase toward DEJ.
- C- Permeability increase toward bcj.
The correct answer is: b- Permeability increases toward DEJ.
Dentine permeability is not uniform throughout the tooth and varies depending on the location:
- Highest permeability:
Dentin closest to the pulp (near the basal cavitas junction (bcj)) has the highest permeability due to the larger diameter of dentinal tubules in this region.
- Lowest permeability:
Dentin near the enamel dentin junction (DEJ) has the lowest permeability because the tubules are narrower and filled with a mineralized material called smear layer.
Therefore, dentine permeability increases as you move away from the DEJ towards the bcj.
Options Summary:
Here's a summary of the options:
a. Coronal less than root dentine:
Not entirely accurate. Permeability can vary within both coronal and root dentine depending on the location relative to DEJ and bcj.
b. Permeability increases toward DEJ:
Incorrect. Permeability actually decreases towards DEJ.
c. Permeability increases toward bcj:
Correct. Permeability is highest near the pulp, close to the bcj.
