In vitro effect of temperature on dentin bond strength of universal adhesive systems

Abstract

The aim of this study was to evaluate the shear bond strength (SBS) of two universal adhesives (Universal Single Bond and All Bond Universal) and a two-step self-etch adhesive system (Clearfil SE Bond) to dentine at various temperatures. Materials and Methods: One hundred and twenty dentin specimens were divided randomly to 12 groups, according to adhesive systems (Universal Single Bond and All Bond Universal, Clearfil SE Bond)  and temperature  ( 4ºC, 20 ºC, 36ºC, 55ºC) used. Dentin specimens were prepared (n :10, adhesives were applied, and composite cylinders were polymerized. Statistical analysis of the SBS data was performed using Two-way analysis of variance (ANOVA) and Tukey’s Honestly Significant Differences post-hoc test. Results: The Clearfil SE Bond was shown to have higher SBS than the universal adhesives at all temperatures; however, there was no statistically significant difference (P>0.05). In both groups, the lowest SBS values were observed in the samples at 4°C while the highest SBS values were observed in the samples at 55°C. In this case, there was a statistically significant difference (P 0.05). En todos los grupos, los valores más bajos de SBS se observaron en las muestras a 4°C, mientras que los valores de SBS más altos fueron obtenidos en las muestras a 55°C (P <0.05). Conclusiones: Los resultados sugieren que la efectividad de un adhesivo puede aumentar si se precalienta a 36°C o superior, antes de usarlo  inmediatamente después de sacarlo del refrigerador o a temperatura ambiente.