Evaluation of Ultrastructural Changes under Scanning Electron Microscopy after Silver Damine Fluoride Application in Primary Teeth with Active Carious Lesion: An In vitro Study

Objective: This in vitro study evaluates the changes at ultrastructural level in the mineral content and surface morphology of primary carious teeth following Silver Diamine Fluoride (SDF) application under Scanning Electron Microscopy (SEM).

Methodology: Six primary molars with active dentinal caries, not involving the pulp, indicated for extraction were collected. Coronal portions were sectioned into two longitudinal halves using copper cutting disc and were divided into two Groups A and B. Group A, the study group, had 6 sections with SDF application; Group B, the control group had 6 sections without SDF application.

All 12 sections were treated with 1% acetic acid for 5 seconds. 38% SDF was applied on Group A sections twice in 2 weeks and were stored in artificial saliva. Group B sections were stored in artificial saliva for the entire study period.

After 2 weeks, 3 samples from Group A(1A, 2A, 3A) and subsequent samples from Group B(1B, 2B, 3B) were taken up for elemental analysis where lines with 500µm were selected randomly from centre of the dentinal lesion towards the pulp, and examined under SEM. The other 3 samples from Group A (4A, 5A, 6A) and subsequent samples from Group B (4B, 5B, 6B) were dehydrated with Ethanol solutions (100%, 96%, 70%, 50%) and studied under SEM for surface morphology.

Result: Higher concentration of Calcium and Phosphate was found in sections treated with SDF. The surface morphology of arrested lesions showed smooth dentinal surface.

Conclusion: A dense, highly mineralized dentinal surface was found on sections treated with 38% SDF.