Effect of Fluoride Varnish Combined with Er:YAG Laser on the Permeability of Eroded Dentin: An In Situ Study

Abstract

This study evaluated the combined effect of fluoride varnish and Er:YAG laser on the permeability of eroded bovine root dentin. After initial erosive challenge followed by a remineralization period, the specimens were divided in two groups according to the treatment - fluoride varnish and non-fluoride varnish - and were subdivided according to the irradiation protocol: Er:YAG laser (100 mJ, 3 Hz, 12.8 J/cm2per pulse, non-contact and defocus mode) and non-irradiated. After a lead-in period, 7 volunteers wore a palatal device containing 4 specimens that were subjected to erosive challenges. At the first experimental phase, 4 volunteers used specimens treated with fluoride varnish and fluoride varnish+Er:YAG laser and 3 volunteers used specimens treated with non-fluoride varnish and non-fluoride varnish+Er:YAG laser. After a washout period, volunteers were crossed to treatments, characterizing a 2x2 crossover experiment. At the end of the experimental phase, the quantitative response variable was obtained by permeability analysis and the qualitative response by scanning electron microscopy (SEM). Two-way ANOVA and Tukey-Kramer's test revealed that specimens treated with fluoride varnish+Er:YAG laser showed the lowest permeability and a significant difference was found between this group and the others. When varnish (fluoride/non-fluoride) was applied in the absence of Er:YAG laser, higher permeability was found when compared to the laser-treated groups. SEM evaluations showed partially or completely obliterated dentinal tubules when specimens were treated with fluoride varnish+Er:YAG laser. It may be concluded that Er:YAG laser was able to control the permeability of eroded root dentin and the combination with fluoride varnish increased laser action.

Comparison of the Effectiveness of Combined Diode Laser and GLUMA Bonding Therapy With Combined Diode Laser and 5% Sodium Fluoride Varnish in Patients With Dentin Hypersensitivity

“…In a study by Nemezio et al, it was found that NaF Varnish and laser GaAIAs are effective in decreasing DH, but the laser is more effective in more severe cases. 15 The use of resins in decreasing hypersensitivity of teeth in some studies has been assessed. First, Brannstrom et al showed the effectiveness of resin in their studies.…”

“…12 As bonding systems continue to evolve with improved physical properties, which more effectively block dentinal tubules, these factors might be an appropriate therapeutic option in the permanent improvement of DH. 13 To date, numerous studies have investigated the effect of simultaneous use of sodium fluoride (NaF) varnish and lasers 14,15 and also the use of resin bands 16,17 to treat hypersensitivity of teeth.…”