مرکز منطقه ای اطلاع رساني علوم و فناوري - The effect of dentin desensitizing agents on the shear bond strength of a one step self-etch adhesive to dentin

Abstract :

Objectives: The objective of this study was to evaluate the effect of 12 different dentin desensitizing agents (DDAs) on the shear bond strength of a one step self- etch adhesive to dentin. Materials and Methods: To that end, one hundred ninety-five intact human mandibular third molar teeth were used in this study. The buccal cervical enamel tissues of teeth were removed to expose cervical dentin. The teeth were randomly divided into 13 treatment groups (n=15). Twelve different DDAs (Smart Protect, Systemp Desensitizer, Seal Protect, Aqua-Prep F, Isodan, Gluma, BisBlock, UltraEZ, D/Sense Crystal, Colgate Sensitive Pro- Relief, Topex ve Clinpro White Varnish) were applied to dentin surfaces according to manufacturers’instructions. No desensitizing treatment was applied to group 13. After desensitizing treatment, all specimens were kept in artificial saliva for 14 days at 37 °C. At the end of this soaking period, all specimen were taken out of the saliva, rinsed with water and dentin surfaces were brushed 8-10 times in circular motion. Clearfil Tri-S Bond (Kuraray Medical Inc, Japan) was applied to dentin surfaces according to manifacturers’ instructions. A microhybride composite resin (Filtek Z 250, 3M ESPE, St Paul, MN, USA) was applied to dentin surfaces according to manifacturers’ instructions by means of cylindrical tubes. Prepared specimens were stored in distilled water and kept in the etuve at 37°C for 24 hours. Shear bond strength test were performed by using Universal Tension/Compression Testing Machine (Instron 3382, USA). The occlusive effect of DHGA on dentin tubuls were examined with SEM by preparing three specimens for each group. The significance of the differences between groups within shearbond strength was investigated with One-Way Analysis of Variance (One-Way ANOVA) and post hoc Tukey test. The mean difference is significant at the 0.05 level. Results: The shear bond strength values of D/Sense Crystal, Topex ve Clinpro White Varnish groups were found statistically lower than the control group (p 0.05). There was no statistically significant difference between the control group and the other groups (Smart Protect, Systemp Desensitizer, Seal Protect, Aqua-Prep F, Isodan, Gluma, BisBlock, UltraEZ, Colgate Sensitive Pro- Relief) Conclusions: In this in vitro study, the application of DDAs which contain fluoride and potassium oxalate reduced the resin-dentin shear bond strength of a one step self-etch adhesive. The possible reason of this situation could be that the penetration of the self-etch adhesive resin that had weak acidity to dentin tubules was prevented by dentin plugs that were produced by these agents as viewed on SEM investigations.