Effect of Er: Cr: YSGG laser on the remineralizing potentialof self-Assembly peptides in incipient carious lesions : (In vitro study).

Abstract

The purpose of this in-vitro study was to compare the remineralizing capacity of self-assembling peptide applied after enamel surface pre-treatment with Er:Cr:YSGG laser, versus the use of laser and self-assembling peptide on their own for the treatment of incipient enamel carious lesion. A total of 32 enamel specimens from human molars were collected and decoronated 2mm below the CEJ. Crowns were embedded in self-cure acrylic resin mold facing upwards. Teeth surfaces were scaled and polished flat to facilitate the micro-hardness test. A 4*4 mm window of exposed enamel was prepared, and the rest was covered with acid-resistant nail varnish. White spot lesions were artificially induced on all enamel samples via immersing the samples individually in a demineralizing solution for 4 days that was daily renewed. After white lesion formation, all samples were rinsed under running water. Enamel samples were then divided into 4 main groups according to the remineralizing regimen; Group I (Artificial saliva) as negative control, Group II (Self-assembly peptide Curodont Repair), Group III (Er:Cr:YSGG laser: pulse duration of 60 microseconds, average power 4W energy, 60% water 40% air, repetition 50 Hz, energy density 15.9 J/cm2, tip in non-contact mode at a distance of 2 mm) and Group IV (Er:Cr:YSGG laser + Self-assembly peptide Curodont Repair) All enamel samples were pH cycled for 14 days, 2 hours in demineralizing solution and 22 hours in remineralizing solution and fresh solution were applied after 4 days. Surface microhardness test was carried out using Vickers testing machine with a 100 g load indenter held for 15 seconds; at baseline, after demineralization and after treatment with pH cycling. Three indentations were made for each reading and their average was taken to represent the specimen’s hardness value. The final results of the study showed that all three treatment modalities promoted remineralization of the demineralized enamel surface lesion. Similar outcomes for groups II and III were obtained, while group IV showed the highest statistical significance.