Combating Dental Caries: LASER vs FLUORIDE

Objectives:

1.To study the effect of laser on enamel surface by SEM analysis.

2.To evaluate induced caries-like lesions formed in fluoridated, lased and lased - fluoridated enamel.

Methods:

45 extracted human impacted molars were used for the study.

Five of these teeth were sectioned bucco-lingually and lased with Nd: YAG laser at 25, 50, 75 and 100 mJs and evaluated for surface topography by SEM analysis.

The remaining 40 teeth were sectioned into four quarters each to get 160 specimens. These were divided into four groups: A-control, B-fluoridated (with 1.23% APF gel for 4 minutes), C-lased (with 50mJs Nd:YAG laser) and D-lased-fluoridated (lased with 50mJs Nd:YAG laser followed by 1.23% APF gel application for 4 minutes). All specimens were suspended in an artificial caries attack system at 37° C for five days, after which half of them from each group were taken out for evaluation of caries initiation. Rest half were kept in the solution for five more days to allow caries progression. Each of the specimens was tested with laser fluorescence (DIAGNOdent) for caries, against the Gold standard, histological evaluation, for caries initiation and progression.

Results:

50mJ laser irradiation was found to give the smoothest surface of all laser energy levels.

Laser fluorescence showed dentin demineralization in 100% specimens of Group A against no demineralization in Group D.

In histological sections, there was highly significant difference in caries initiation and progression between Groups A, B, C and D (p>0.05), with least values of both in group D.

Conclusions:

In the present study, the combination of fluoride and laser treatment was found to be the best for combating dental caries.

Diagnosis by laser fluorescence showed results comparable to histological gold standard.