[ effect of the light activation mode on incompatibility between one-bottle adhesives and light-cured composites: an in-vitro shear bond strength study]

Adverse surface interactions between one-bottle adhesives and self-cured composites may occur similarly with light-cured composites during the use of different modes of light activation. The study examined the effect of different light activation modes of light-cured composite on the shear bond strength of 2 one-bottle adhesives with different acidity to the dentin. The experimental study was performed on 110 extracted sound molars. Then, the teeth were randomly divided into 10 equal groups [n=11]. One-Step plus [OS] and Prime and Board NT [P and B NT] were [SSI]. Soft- Start II [SSII], Pulse-Delay I [PDI], Pulse- Delay II [PDII]. Then, shear bond strength [SBS] test was performed, using an Instron at 1mm/min. The SBS was recorded in MPa. Statistical analysis included two way ANOVA with a significance level of 0.05. The highest SBS [MPa] was shown in OS conventional group [19.62] and the lowest in P and B NT, PDII [5.43]. In each group of 5 curing mode, mean SBS in P and B NT was significantly lower than that in OS as follows: In conventional; P and B NT [17.27] vs OS [19.82] in SSI; P and B NT [10.89] vs OS [13.09] in SSII; P and B NT [14.48] vs. OS [18.79] in PDI; P and B NT [5.93] vs OS [11.97] and in PDII; P and B NT [11.82] vs OS [16], [p<0.001]. In each of 2 adhesives, ranking of SBS from minimum to maximum was as follows: PDI