title: Reliability of the dye penetration studies.
abstract: The purpose of this study was to compare the classical dye-penetration method to a dye-extraction method, with a fluid-filtration method as control. Forty teeth were prepared with a ProFile device and divided into four groups (n = 10 per group) according to the sealer used for the lateral condensation: Pulp Canal Sealer, Sealapex, AH Plus, and Ketac-Endo. The apical seal was evaluated on the same teeth with all three methods, successively: a fluid-filtration method, a dye-penetration method with 2% methylene blue, and a new method where the roots were dissolved in 65% nitric acid to extract the methylene blue before reading the absorbance of the solution. The classical dye penetration did not show any difference among the sealers and showed no correlation with the two other techniques. The fluid filtration (p < 0.01) and the dye extraction (p < 0.01) showed that Sealapex displayed the highest apical leakage. The correlation between the results obtained with these two methods was significant (p = 0.001 and r = 0.7). This study showed the limitation of the classical dye-penetration studies and that the dye-extraction, i.e. dissolution, method gave the same results as fluid filtration but saved much laboratory time.
mesh_terms: D000704:Analysis of Variance; D002126:Calcium Hydroxide / Q000737:chemistry; D003124:Colorimetry; D004396:Coloring Agents; D001840:Dental Bonding; D003763:Dental Leakage / Q000175:diagnosis*; D004853:Epoxy Resins / Q000737:chemistry; D005374:Filtration; D005899:Glass Ionomer Cements / Q000737:chemistry; D006171:Gutta-Percha / Q000737:chemistry; D006801:Humans; D008751:Methylene Blue; D017942:Nitric Acid; D015203:Reproducibility of Results; D012387:Root Canal Filling Materials / Q000737:chemistry*; D012459:Salicylates / Q000737:chemistry; D012997:Solvents; D019227:Tooth Apex / Q000473:pathology; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D004853:Epoxy Resins; D005899:Glass Ionomer Cements; C074934:Ketac Endo; D012387:Root Canal Filling Materials; D012459:Salicylates; D012997:Solvents; D015035:Zinc Oxide-Eugenol Cement; C534916:epoxy resin-based root canal sealer; C055601:Sealapex; D017942:Nitric Acid; C076543:Kerr Pulp Canal Sealer; D006171:Gutta-Percha; D002126:Calcium Hydroxide; D008751:Methylene Blue