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 .
Effect of Er:YAG laser irradiation on bonding property of zirconia ceramics to resin cement.
OBJECTIVE This study aim ed to investigate whether or not an erbium : yttrium-aluminum-garnet ( Er : YAG ) laser could improve the bonding property of zirconia ceramics to resin cement . BACKGROUND DATA Surface treatments can improve the bonding properties of dental ceramics . However , little is known about the effect of Er : YAG laser irradiated on zirconia ceramics . MATERIAL S AND METHODS Specimens of zirconia ceramic pieces were made , and r and omly divided into 11 groups according to surface treatments , including one  control group ( no treatment )  ,  one air abrasion group  , and  nine Er : YAG laser groups .  The laser groups were subdivided by applying different energy intensities ( 100 , 200 , or 300 mJ ) and irradiation times ( 5 , 10 , or 15 sec ) . After surface treatments , ceramic pieces had their surface morphology observed , and their surface roughness was measured . All specimens were bonded to resin cement . Shear bond strength was measured after the bonded specimens were stored in water for 24 h , and additionally aged by thermocycling . Statistical analyses were performed using one way analysis of variance ( ANOVA ) and Tukey 's test for shear bond strength , and Dunnett 's t test for surface roughness , with α=0.05 . RESULTS Er : YAG laser irradiation changed the morphological characteristics of zirconia ceramics . Higher energy intensities ( 200 , 300 mJ ) could roughen the ceramics , but also caused surface cracks . There were no significant differences in the bond strength between the control group and the laser groups treated with different energy intensities or irradiation times . Air abrasion with alumina particles induced highest surface roughness and shear bond strength .  CONCLUSIONS Er : YAG laser irradiation can not improve the bonding property of zirconia ceramics to resin cement . Enhancing irradiation intensities and extending irradiation time have no benefit on the bond of the ceramics , and might cause material defect
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 .