MICRORADIOGRAPHY AND CONFOCAL LASER-SCANNING MICROSCOPY APPLIED TO ENAMEL LESIONS FORMED IN-VIVO WITH AND WITHOUT FLUORIDE VARNISH TREATMENT

The aim of the present investigation was to combine 2 techniques suita ble for lesion characterization: quantitative microradiography (TMR) a nd confocal laser scanning microscopy (CLSM) on in vivo induced lesion s with and without a fluoride varnish (Duraphat(R)) treatment. Orthodo ntic bands were attached to premolars to be extracted for orthodontic reasons to induce enamel caries on the buccal surfaces. In the caries development part of the study, 1 tooth of each pair received at the st art 1 topical application with the fluoride varnish Duraphat(R), the c ontralateral tooth serving as untreated control. All teeth were extrac ted after 4 weeks. In the caries progression part, the premolars were banded for 4 weeks without any treatment to induce caries. 1 premolar in each pair was then extracted and analyzed, The contralateral tooth received one Duraphat(R) application and was extracted after another 2 weeks. In the caries development part of the study, TMR analysis show ed that the Duraphat(R) treatment on sound enamel reduced lesion depth by 48% compared to the untreated control. In the caries progression p art, no significant difference was found between the untreated teeth e xtracted after 4 weeks and the fluoride treated lesions extracted afte r another 2 weeks, CLSM images agreed well with the TMR measurements. In the fluoride treated lesions, the CLSM images showed more light sca ttering indicating precipitation of material.