comparition the effect of type of universal bonding application strategy on marginal adaptation of bulk fill and conventional composite in classII restorations.

Abstract

Abstract Background and aim:The aim of this in vitro study was to compare the effect of typeof universal bonding application strategy (i.e. self etch‚etch&rinse) on marginal adaptation of bulk fill and conventional composite in classII restorations. Methods and materials: 60 sound premolars, extracted for orthodontic reasons, were selected.In this study futurabond U (Voco) as universal bonding agent, X-tra fill (Voco) as bulk fill composite and Grandio (Voco) as conventional composite were used. Samples were allocated to 4 groupsbased onthe type of universal bonding application sterategy (self etch‚etch & rinse) and type of composite (bulk fill‚ conventional). In each group boxes with depth of 4mm on the mesial surfaces were preparedand after matrix placement the teeth were restored in different groups basedon thethetype of the universal bonding application sterategyand type of composites. Finally themarginal adaptation of the samples was evaluated under stereomicroscope at 60×magnification.Inorder tocompare the marginal adaptationbetween two universal bonding applicationstrategies in each type of composite groupIndependent Samples t Test was used. Two-way ANOVA was used to compare the marginal adaptationdata in the study groupsconsidering the type of universal bonding application sterategy and type of composite.Statistical significance was set at P<0.05. Results:Considering the type of universal bonding application strategy, there wasstatistically significant difference in marginal adaptation‚ and the etch& rinse strategy showed better marginal adaptation compared to self etch strategy (P< 0.05). However, there was no statistically significant difference in marginal adaptation between two composites (P>0.05).Furthermore, the interaction between two factors(type of universal bonding application strategy and type of composite) was not statis¬tically significant (P>0.05).In other words the influence of the universal bonding application strategy on the marginal adaptationwas the same for two types of composites. Conclusion: The etch & rinse bonding application sterategyin the both bulkfilland conventional composites showed better marginal adaptationthan self etchbonding application sterategy. However, the marginal adaptation difference between two types of composites(bulk and conventional) was not significant.