Carolina Menezes Maciel1, Marcelo Ferreira da Rosa Rinhel2, Gabriel Flores Abuna3, Rafael Rocha Pacheco4, Laís Regiane da Silva-Concílio1, Kusai Baroudi1, Mário Alexandre Coelho Sinhoreti3, Rafael Pino Vitti5,6. 1. School of Dentistry, University of Taubate, Taubate, SP, Brazil. 2. São Carlos School of Engineering, University of São Paulo, São Carlos, SP, Brazil. 3. Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil. 4. School of Dentistry, University of Detroit Mercy, Detroit, MI, USA. 5. School of Dentistry, University of Taubate, Taubate, SP, Brazil. rafapvitti@gmail.com. 6. School of Dentistry, Herminio Ometto University Center, Av. Dr. Maximiliano Baruto, 500, Araras, SP, CEP: 13607-339, Brazil. rafapvitti@gmail.com.
Abstract
OBJECTIVES: To evaluate the effect of electric current application on the resin composite-tooth bond strength and hybrid layer of three adhesive systems light-cured by two light-curing units (LCUs). MATERIALS AND METHODS: Human molar teeth were distributed into 12 groups (n=6). Three adhesive systems were used: two-step etch-and-rinse (SB2; Adper Single Bond 2, 3M ESPE); two-step self-etch (CSE; Clearfil SE Bond, Kuraray); and one-step self-etch (SBU; Single Bond Universal, 3M ESPE) applied with (50μA) and without (control; conventional application) electric current, and light-cured with different LCUs. Resin composite blocks (Filtek Z350XT, 3M ESPE) were produced and cut into sticks (~1mm2) for microtensile bond strength (μTBS). Fracture patterns were analyzed on stereomicroscope and classified as cohesive-dentin, cohesive-resin, adhesive, or mixed. Specimens were prepared for scanning electron microscope observation. The hybrid layer analysis was carried out using a confocal laser scanning microscopy (n=2). Data were submitted to three-way ANOVA followed by Tukey's post hoc test (α=0.05). RESULTS: The electric current increased the μTBS for all adhesive systems light-cured with single-emission peak and multiple-emission peak LCUs. Both LCUs presented similar μTBS values. CSE applied under electric current showed the highest μTBS mean values. The adhesive failure pattern was more frequently observed in all groups. The electric current formed long resin tags for all adhesive systems. CONCLUSIONS: The adhesive systems applied under electric current increased the bond strength using single-emission peak and multiple-emission peak LCUs. CLINICAL RELEVANCE: Electric current at 50μA applied throughout the dentin is a safe mode and results in better impregnation of the adhesive systems.
OBJECTIVES: To evaluate the effect of electric current application on the resin composite-tooth bond strength and hybrid layer of three adhesive systems light-cured by two light-curing units (LCUs). MATERIALS AND METHODS:Human molar teeth were distributed into 12 groups (n=6). Three adhesive systems were used: two-step etch-and-rinse (SB2; Adper Single Bond 2, 3M ESPE); two-step self-etch (CSE; Clearfil SE Bond, Kuraray); and one-step self-etch (SBU; Single Bond Universal, 3M ESPE) applied with (50μA) and without (control; conventional application) electric current, and light-cured with different LCUs. Resin composite blocks (Filtek Z350XT, 3M ESPE) were produced and cut into sticks (~1mm2) for microtensile bond strength (μTBS). Fracture patterns were analyzed on stereomicroscope and classified as cohesive-dentin, cohesive-resin, adhesive, or mixed. Specimens were prepared for scanning electron microscope observation. The hybrid layer analysis was carried out using a confocal laser scanning microscopy (n=2). Data were submitted to three-way ANOVA followed by Tukey's post hoc test (α=0.05). RESULTS: The electric current increased the μTBS for all adhesive systems light-cured with single-emission peak and multiple-emission peak LCUs. Both LCUs presented similar μTBS values. CSE applied under electric current showed the highest μTBS mean values. The adhesive failure pattern was more frequently observed in all groups. The electric current formed long resin tags for all adhesive systems. CONCLUSIONS: The adhesive systems applied under electric current increased the bond strength using single-emission peak and multiple-emission peak LCUs. CLINICAL RELEVANCE: Electric current at 50μA applied throughout the dentin is a safe mode and results in better impregnation of the adhesive systems.
Entities:
Keywords:
Bond strength; Dentin; Electrical current; Hybrid layer; Resin composite
Authors: Shuichi Ito; Franklin R Tay; Masanori Hashimoto; Masahiro Yoshiyama; Takashi Saito; William W Brackett; Jennifer L Waller; David H Pashley Journal: J Adhes Dent Date: 2005 Impact factor: 2.359