title: Effect of Non-Thermal Argon Plasma on Bond Strength of a Self-Etch Adhesive System to NaOCl-Treated Dentin.
abstract: Studies have been showing a decrease of bond strength in dentin treated with sodium hypochlorite (NaOCl). The aim of this study was to evaluate the effect of non-thermal argon plasma on the bond strength of a self-etch adhesive system to dentin exposed to NaOCl. Thirty-two flat dentin surfaces of bovine incisors were immersed in 2.5% NaOCl for 30 min to simulate the irrigation step during endodontic treatment. The specimens were divided into four groups (n=8), according to the surface treatment: Control (without plasma treatment), AR15 (argon plasma for 15 s), AR30 (argon plasma for 30 s) and AR45 (argon plasma for 45 s). For microtensile bond strength test, 5 specimens were used per group. In each group, the specimens were hybridized with a self-etch adhesive system (Clearfil SE Bond) and resin composite buildups were constructed. After 48 h of water storage, specimens were sectioned into sticks (5 per tooth, 25 per group) and subjected to microtensile bond strength test (μTBS) until failure, evaluating failure mode. Three specimens per group were analyzed under FTIR spectroscopy to verify the chemical modifications produced in dentin. μTBS data were analyzed using ANOVA and Tamhane tests (p<0.05). AR30 showed the highest μTBS (20.86±9.0). AR15 (13.81±6.4) and AR45 (11.51±6.8) were statistically similar to control (13.67±8.1). FTIR spectroscopy showed that argon plasma treatment produced chemical modifications in dentin. In conclusion, non-thermal argon plasma treatment for 30 s produced chemical changes in dentin and improved the μTBs of Clearfil SE Bond to NaOCl-treated dentin.
authors.affiliation: Department of Dental Clinic, Dental School, UFRJ - Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: João Luiz Bittencourt de
authors.initials: JL
authors.lastname: Abreu
authors.affiliation: Department of Dental Clinic, Dental School, UFRJ - Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.|Department of Dental Clinic, Dental School, UFRJ - Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Maíra
authors.initials: M
authors.lastname: Prado
authors.affiliation: Laboratory of Polymer and Asphalt Surfaces, School of Metallurgical and Materials Engineering, UFRJ - Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Renata Antoun
authors.initials: RA
authors.lastname: Simão
authors.affiliation: Analytical Laboratory of Restorative Biomaterials, Dental School, UFF - Universidade Federal Fluminense, Niterói, RJ, Brazil.
authors.forename: Eduardo Moreira da
authors.initials: EM
authors.lastname: Silva
authors.affiliation: Department of Dental Clinic, Dental School, UFRJ - Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Katia Regina Hostilio Cervantes
authors.initials: KR
authors.lastname: Dias
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D001128:Argon / Q000737:chemistry*; D003804:Dentin / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D058626:Plasma Gases; D012973:Sodium Hypochlorite / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D058626:Plasma Gases; D001128:Argon; D012973:Sodium Hypochlorite