Remineralizing Fluoridated Paste and Argon Laser: Enamel Surface Topography Effects

Objectives: This in vitro study evaluated remineralizing fluoridated paste (RFP) and argon laser treatment (ALT) effects on enamel surfaces using scanning electron microscopy (SEM). Methods: 10 human extracted teeth with caries-free enamel surfaces were divided into 4 portions after fluoride-free prophylaxis. Each tooth portion underwent a different treatment: No Treatment Control (portion 1); RFP (portion 2, MI Paste Plus, GC America, Alsip 60803); ALT (portion 3, LaserMed, West Jordan 84088); RFP after ALT (portion 4). RFP group was treated for 120s, and then rinsed in deionized/distilled water to remove excess RFP. ALT group was treated for 10s at 13.5 Joules/cm² (0.27W, 5mm beam), and then rinsed in deionized/distilled water. RFP after ALT group was treated with argon laser (10s) followed by RFP (120s), and then rinsed in deionized/distilled water. Control group was rinsed with deionized/distilled water. Specimens were examined with SEM. Results: No Treatment Control group had intact enamel surfaces with frequent enamel prism ends. RFP group had relatively smooth, uniform surface coatings masking the majority of the enamel prism ends. ALT group had roughened irregular surfaces with obvious surface porosities and granular precipitates with no enamel prism ends. RFP after ALT group had finely granular to obviously porous surface coatings with no enamel prism ends. With RFP after ALT groups, fractured areas in the surface coatings revealed globular precipitates, morphologically resembling calcium fluoride. Conclusions: RFP created relatively uniform surface coatings, most likely rich in calcium, phosphate and fluoride mineral phases. ALT produced irregular enamel surfaces that most likely would be reactive with saliva, fluoride and remineralizing agents. Combination of ALT with RFP provided surface coatings that had finely granular to globular precipitates which most likely were comprised of calcium-phosphate-fluoride rich mineral phases. Creation of reactive surfaces and surface coatings rich in calcium, phosphate and fluoride may enhance caries resistance.