The Impact of CO2 Laser Treatment and Acidulated Phosphate Fluoride on Enamel Demineralization and Biofilm Formation

Abstract

Introduction: This study evaluated the impact of CO 2 laser treatment and acidulated phosphate fluoride (APF) on enamel demineralization and biofilm formation, using in vitro and in situ designs. Methods: Demineralized enamel slabs were distributed among 8 groups: placebo, placebo + continuous CO 2 laser, placebo + repeated CO 2 laser, placebo + ultrapulsed CO 2 laser, 1.23% APF, APF + continuous CO 2 laser, APF + repeated CO 2 laser and APF + ultrapulsed CO 2 laser. In the in vitro study, 15 enamel slabs from each group were subjected to a pH-cycling regimen for 14 days. In the cross over in situ design, 11 volunteers wore palatal appliances with demineralized enamel slabs for 2 periods of 14 days each. Drops of sucrose solution were dripped onto enamel slabs 8×/day. Biofilms formed on slabs were collected and the colony-forming units (CFU) of Streptococcus mutans and Lactobacillus were determined. Results: For both in vitro and in situ studies, there was no significant difference between treatments (P > 0.05). However, all treatments increased microhardness of demineralized enamel (P < 0.05). After a further in situ cariogenic challenge, with the exception of the placebo, all treatments maintained microhardness values (P < 0.05). Microbiological analysis showed no difference in Streptococcus mutans (P > 0.05) or Lactobacillus (P > 0.05) counts between groups. Conclusion:The results suggest that APF gel combined with the CO 2 laser, regardless of the pulse emission mode used, was effective in controlling enamel demineralization, but none of the tested treatments was able to prevent bacterial colonization.

Effects of Two Remineralizing agents in Combination with Er:YAG and CO2 Laser Irradiation on Microhardness of Demineralized Enamel: A Preliminary In Vitro Study

“…Evidence shows that CO 2 laser irradiation may block the dentinal tubules by dentin melted due to high temperature at the irradiation site. It can remove water, organic compounds, and carbonate ions that have been substituted into the hydroxyapatite structure over time, increasing the mineral composition of enamel [ 7 - 9 , 27 ].…”

“…Calcium phosphate-based remineralizing agents have shown promising results in non-invasive management of incipient carious lesions [ 5 , 6 ]. Different materials and methods have been proposed for this purpose [ 4 , 5 , 7 - 14 ].…”

“…Laser irradiation‎ is another approach proposed as a supplement for prevention of dental caries [ 7 - 9 ]. Some studies investigated the potential preventive effects of laser irradiation on enamel and dentin [ 14 , 16 ].…”

Effect of a Combination of Photodynamic Therapy and Chitosan on Streptococcus mutans (An In Vitro Study)

“…Despite the advances in caries control programs and increased use of fluoride, the prevalence of dental caries is still high worldwide. 1,2 Dental caries can cause pain and affect patients' quality of life. 3,4 Dental caries has a multifactorial origin and is caused by the interaction of some internal factors such as decreased salivary flow, tooth surface morphology, poor nutritional status and hormonal conditions and external factors such as microbial flora, poor oral hygiene and low access to fluoride.…”