Effect of enamel surface treatment via Er, Cr: YSGG laser and nano-hydroxyapatite toothpaste on mineral content of primary teeth via x-ray diffractometer: an in-vitro study

PURPOSE: This study evaluated the effect of Er,Cr:YSGG laser treatment, with or without nano-hydroxyapatite (nHAP) toothpaste, on the mineral content of primary enamel specimens, with emphasis on their remineralization potential in pediatric dentistry. MATERIALS AND METHODS: This in vitro study included 33 sound primary anterior teeth, from which enamel slabs were prepared and subjected to demineralization for 96 hours. Specimens were randomly assigned to three groups (n = 11): Group A (nHAP toothpaste), Group B (Er,Cr:YSGG laser, 2780 nm), and Group C (combined laser and nHAP toothpaste). Mineral phase composition was assessed using X-ray diffraction (XRD). RESULTS: Quantitative phase analysis revealed an increase in apatite crystal content in all groups following treatment. Group C showed the highest increase (7.4%) and exhibited a complete transformation into apatite structures. Groups A and B demonstrated comparable increases (5.1% and 4.8%, respectively), with no statistically significant difference between them. CONCLUSIONS: Both Er,Cr:YSGG laser irradiation and nHAP toothpaste enhanced apatite formation in demineralized primary enamel; however, their combined application produced the most pronounced remineralization effect.