N L Maung1, T Wohland, C-Y S Hsu. 1. Department of Preventive Dentistry, Faculty of Dentistry, 5 Lower Kent Ridge Road, National University of Singapore, Singapore 119074, Singapore.
Abstract
UNLABELLED: Several studies have demonstrated the caries protective effect of lasers by strengthening enamel crystalline structure. However, the effect of laser on enamel diffusion (ED) remains unclear. OBJECTIVES: This study aimed to quantify the laser-induced alteration of diffusion coefficients (DC) in enamel using fluorescence recovery after photobleaching (FRAP). METHODS: Eleven caries-free enamel sections were characterized morphologically using stereomicroscopy, polarized light microscopy and scanning electron microscopy, before and after laser treatment with Er:YAG laser 50 mJ x 5 s x 5 Hz. With 20 microM fluorescein, DCs were measured (n=11) by FRAP coupled with confocal microscopy. RESULTS: The DCs measured were 2.89+/-0.61 x 10(-7)cm(2)/s and 4.076+/-0.73 x 10(-7)cm(2)/s, at the lased and unlased areas, respectively (p=0.001). CONCLUSIONS: This study has confirmed the reduction of ED as a potential mechanism involved in laser-induced caries prevention. FRAP was demonstrated to be a promising technique for evaluating diffusion-related phenomenon in enamel.
UNLABELLED: Several studies have demonstrated the caries protective effect of lasers by strengthening enamel crystalline structure. However, the effect of laser on enamel diffusion (ED) remains unclear. OBJECTIVES: This study aimed to quantify the laser-induced alteration of diffusion coefficients (DC) in enamel using fluorescence recovery after photobleaching (FRAP). METHODS: Eleven caries-free enamel sections were characterized morphologically using stereomicroscopy, polarized light microscopy and scanning electron microscopy, before and after laser treatment with Er:YAG laser 50 mJ x 5 s x 5 Hz. With 20 microM fluorescein, DCs were measured (n=11) by FRAP coupled with confocal microscopy. RESULTS: The DCs measured were 2.89+/-0.61 x 10(-7)cm(2)/s and 4.076+/-0.73 x 10(-7)cm(2)/s, at the lased and unlased areas, respectively (p=0.001). CONCLUSIONS: This study has confirmed the reduction of ED as a potential mechanism involved in laser-induced caries prevention. FRAP was demonstrated to be a promising technique for evaluating diffusion-related phenomenon in enamel.
Authors: R S Scatolin; V Colucci; T P Lepri; A K Alexandria; L C Maia; R Galo; M C Borsatto; S A M Corona Journal: Lasers Med Sci Date: 2014-07-02 Impact factor: 3.161