According to this review , the 3-step adhesive systems were the best performing and still are the gold st and ard for the cementing of indirect restorations .
In addition , it can be concluded that self-etched adhesive systems reduce the time spent in clinical practice , however at the interface level they behave as permeable membranes more susceptible to degradation
New technologies are changing the therapeutical options to do indirect restorations and new adhesive systems are continuously introduced to be used by clinicians .
Different interactions between restorations , adhesive systems components , enamel and dentin require having criteria based on the selection of the adhesive system , ensuring the longevity of the restorations and the preservation of the biological remnant .
The adhesion force to the dental tissue is one of the indicatives of the behavior of the adhesive systems and influences the behavior of the treatments with direct and indirect restorations .
The objective of this search was to find the adhesive systems with the best results in terms of the adhesion strength of indirect restorations  on the dental tissues .
Effect of selective enamel etching on clinical performance of CAD/CAM partial ceramic crowns luted with a self-adhesive resin cement
Objectives This study was conducted to evaluate a self-adhesive resin luting cement [ RelyX Unicem 3MESPE – RXU ] for  luting partial ceramic crowns ( PCCs )  with and without selective enamel etching in a prospect i ve , r and omized clinical trial . Material s and methods Thirty-four patients had received the intended treatment . Two PCCs ( Vita Mark II ; Cerec 3D ; Sirona ) had been placed in a split-mouth design : one with RXU without enamel etching ( RXU ) , the other with RXU with selective enamel etching ( RXU + E ) . Restorations were evaluated at baseline ( BL ) and after 12 , 24 , and 36 months ( USPHS criteria ) . For statistical analysis , the Chi-square test was applied ( α = 0.05 ) . Clinical survival of all restorations ( n = 68 ) after 3 years was determined using Kaplan – Meier analysis . Results Twenty three patients ( 12 male/11 female ) were available for clinical evaluation after 3 years . 19 RXU-PCCs were placed in molars , four in premolars , 18 RXU + E – PCCs in molars , five in premolars . Concerning clinical changes , no significant differences were found between luting strategies RXU/RXU + E at all recalls . Statistically significant changes over time were observed for marginal adaptation and marginal discoloration between BL and 36 m for RXU and RXU + E. For RXU + E , postoperative hypersensitivities decreased significantly from BL ( n = 6 ) to 36 m ( n = 0 ) . Of the 68 restorations originally included , eight RXU and four RXU + E restorations failed . At 3 years , Kaplan – Meier survival  of RXU was 72.9 % , that of RXU + E 87.6 % . Survival rates were not statistically significant different . Conclusions Although clinical survival of RXU + E is slightly better at 3 years , restorations of both groups perform similar with respect to clinical changes over time as evaluated by modified USPHS criteria . Clinical relevance The self-adhesive resin cement RXU can be used in conjunction with selective enamel etching , because survival rates of PCCs in the RXU + E group were not lower but , as a trend , even better than without enamel etching
According to this review , the 3-step adhesive systems were the best performing and still are the gold st and ard for the cementing of indirect restorations .
In addition , it can be concluded that self-etched adhesive systems reduce the time spent in clinical practice , however at the interface level they behave as permeable membranes more susceptible to degradation
New technologies are changing the therapeutical options to do indirect restorations and new adhesive systems are continuously introduced to be used by clinicians .
Different interactions between restorations , adhesive systems components , enamel and dentin require having criteria based on the selection of the adhesive system , ensuring the longevity of the restorations and the preservation of the biological remnant .
The adhesion force to the dental tissue is one of the indicatives of the behavior of the adhesive systems and influences the behavior of the treatments with direct and indirect restorations .
The objective of this search was to find the adhesive systems with the best results in terms of the adhesion strength of indirect restorations  on the dental tissues .