Conclusions .
Airborne-particle abrasion and tribo-chemical silica coating are the pre-treatment methods with more evidence in the literature .
Increased adhesion could be expected after physico-chemical conditioning of zirconia .
Surface contamination has a negative effect on adhesion .
There is no evidence to support a universal adhesion protocol
Background .
Reliable bonding between resin composite cements and high strength ceramics is difficult to achieve because of their chemical inertness and lack of silica content that makes etching impossible .
The purpose of this review is to classify and analyze the existing methods and material s suggested to improve the adhesion of zirconia to dental substrate by using composite resins , in order to explore current trends in surface conditioning methods with predictable results .
Methods .
Fatigue behavior of the resinous cement to zirconia bond.
PURPOSE Resinous cements are widely used for luting zirconia restorations . Adhesive failures have occurred at the cement/zirconia interface , rather than at the cement/dentin interface , suggesting that the cement/zirconia bond may lack durability ; however , few comprehensive , comparative evaluations of fatigue effects have been reported . The rate of fatigue-induced loss of bond strength may be a more important predictor of long-term success than a single snapshot of bond strength after an arbitrary number of thermocycles . Previous studies have failed to identify trends by investigating bond strengths at several different numbers of cycles . This may result in invalid conclusions about which cements have superior bond strengths . The purpose of this study was to investigate the effects of artificial aging by thermocycling and resinous cement type on bond strengths to zirconia . MATERIAL S AND METHODS The effect of the number of thermocycles ( 0 , 1 , 10 , 100 , 1000 , and 10,000 ) on the bond strengths of  five resinous cements  , two of which were used with and without a primer , and an oxygen-inhibiting gel , was studied . Specimens were r and omly assigned to thermocycle number/cement-type test groups . Because zirconia has a very low thermal diffusivity , exceptionally long thermocycle dwell times were used . Cylinders of zirconia were bonded end-to-end . One end of each bonded specimen was insulated , specimens were thermocycled and tested in shear , and bond strengths were calculated and analyzed . RESULTS Two-way ANOVA revealed that the effects of cement type , the number of thermocycles , and their interaction all significantly affected bond strength ( p < 0.0001 ) . By 10,000 cycles , most cements had lost at least half of their initial bond strengths , and two cements effectively recorded zero bond strengths . Failure modes were cement specific , but adhesive modes predominated . Fatigue resistance of two cements was greatly improved by use of a primer and an oxygen-inhibiting gel , as recommended by their respective manufacturers . CONCLUSIONS Both the type of resin cement and the number of thermocycles influenced bond strength . Fatigue through thermocycling affected different cement types in different ways . Some material s displayed more rapid loss of bond strength than others . Cements differed in their failure modes
Conclusions .
Airborne-particle abrasion and tribo-chemical silica coating are the pre-treatment methods with more evidence in the literature .
Increased adhesion could be expected after physico-chemical conditioning of zirconia .
Surface contamination has a negative effect on adhesion .
There is no evidence to support a universal adhesion protocol
Background .
Reliable bonding between resin composite cements and high strength ceramics is difficult to achieve because of their chemical inertness and lack of silica content that makes etching impossible .
The purpose of this review is to classify and analyze the existing methods and material s suggested to improve the adhesion of zirconia to dental substrate by using composite resins , in order to explore current trends in surface conditioning methods with predictable results .
Methods .