Dental Enamel Irradiated with a Low-Intensity Infrared Laser and Photoabsorbing Cream: A Study of Microhardness, Surface, and Pulp Temperature

Objective: The aim of this study was to assess the effect of low-intensity infrared laser light (λ=810 nm, 100 mW/cm 2 , 90 sec, 4.47 J/cm 2 , 9 J) with or without indocyanine green cream fluorinated or not fluorinated, using Knoop surface microhardness analysis. Background data: Lasers can be used as tools for the prevention of tooth enamel demineralization. Methods: The surface and pulp temperatures of the human deciduous tooth enamel were measured. For the analysis of surface hardness, a total of 48 specimens were prepared and randomly assigned into six groups ( n =8/group): C (+), which received laser light; C(-), which received no treatment; cream (IV); cream and fluoride (IVF); cream and light (IVL); and cream and fluoride and light (IVFL). The specimens were subjected to treatment before demineralizing challenge by pH cycling. To analyze the surface and pulp temperatures, the samples were divided into the following groups ( n =10): C(+), IVL, and IVFL. Results: The hardness analysis indicated that the groups that received irradiation had less hardness reduction following the demineralizing challenge ( p