Life Cycle Of Ameloblast

Describe the life cycle of ameloblasts.
Answer:

Life-cycle of ameloblasts:

1. Morphogenetic stage:

Cells of the dental epithelium are separated from the dental papilla by a basement membrane.
The cells of the inner dental epithelium are cuboidal or low columnar.
The nucleus is large and centrally located.
The Golgi apparatus is poorly developed and present in the proximal portion of the cells.
Mitochondria and other organelles are scattered throughout the cell.
Ameloblasts interact with the adjacent mesenchymal cells, determining the shape of the dentin enamel junction and the crown.
The terminal bars are points of close contact between cells.

2. Organizing stage:

The inner enamel epithelium interacts with the adjacent connective tissue cells, which differentiate into the odontoblast.
The cells elongate and their nuclei shift proximally towards the stratum intermedium.
The Golgi complex increases in volume and migrates distally from its proximal position.
Thus, ameloblast becomes a polarised cell, with the majority of its organelles situated in the cell body distal to the nucleus.
During the terminal phase of this stage, dentin formation by the odontoblasts begins.
After dentin formation, the ameloblasts are cut off from their original sources of nourishment.
They are then supplied by tire capillaries that surround and may even penetrate tire outer enamel epithelium.

3. Formative stage:

The first layer of dentin is formed.
Epithelial cells come into close contact with the connective tissue of the pulp, and dentin formation begins.
Enamel matrix begins to form.
During it, ameloblasts retain the same length and arrangement.
Blunt cell processes develop on the ameloblast surfaces, which penetrate tire basal lamina and enter tire prevention.

4. Maturative stage:

After most of the enamel matrix is formed in the occlusal or incisal area, enamel maturation begins.
But during this, the enamel matrix is still forming at the tire cervical area.
During this stage, ameloblasts reduce in size and are closely attached to the enamel matrix.
They contain microvilli at distal extremities.
The cells of the stratum intermedium assume a spindle shape.

5. Protective stage:

By this stage, the enamel is completely developed and fully calcified.
The cells of stratum intermedium and outer enamel epithelium form reduced enamel epithelium. Functions of reduced enamel epithelium:
Protect the mature enamel.
Separate it from the connective tissue until the tooth erupts.
This prevents the development of anomalies.

6. Desmolytic stage:

The reduced enamel epithelium proliferates and causes atrophy of the connective tissue to separate it from the oral epithelium.
This results in the fusion of reduced enamel epithelium and oral epithelium.
Epithelial cells secrete enzymes that destroy connective tissue fibers by hemolysis.

Reader Interactions