Apoptosis in pulp elimination during physiological root resorption in human primary teeth.

Area of Science:

• Cell Biology
• Developmental Biology
• Dentistry

Background:

• Physiological root resorption is a natural process in tooth development.
• The precise mechanisms of pulp tissue elimination during root resorption are not fully understood.

Purpose of the Study:

• To investigate the role of apoptosis in pulp tissue elimination during physiological root resorption in human primary teeth.
• To compare the incidence of apoptosis in primary versus permanent teeth undergoing root resorption.

Main Methods:

• Examined pulp samples from 50 healthy human teeth (30 primary, 20 permanent).
• Utilized morphological assessment, TUNEL assay for DNA fragmentation, and electrophoresis for DNA fragmentation patterns.
• Calculated the apoptotic index for both groups.

Main Results:

• Primary teeth showed a significantly higher apoptotic index (51.01%) compared to permanent teeth (25.32%).
• TUNEL assay revealed intense, diffuse labeling in primary teeth pulp, indicating widespread apoptosis.
• Electrophoresis confirmed specific internucleosomal DNA fragmentation, characteristic of apoptosis, in primary teeth but not in permanent teeth.

Conclusions:

• Apoptosis is a significant mechanism involved in pulp elimination during physiological root resorption of human primary teeth.
• The findings highlight distinct cellular processes governing root resorption in primary versus permanent dentition.