No overall effect was revealed in the meta-analyses , meaning that no influence of the  ER or SE strategy on POS .
SIGNIFICANCE The type of adhesive strategy ( ER or SE ) for posterior resin composite restorations does not influence the risk and intensity of POS .
OBJECTIVES A systematic review and meta- analysis were performed on the risk and intensity of postoperative sensitivity ( POS ) in posterior resin composite restorations bonded with self-etch ( SE ) and etch- and -rinse ( ER ) adhesives .
Effect of acid etching time and technique on interfacial characteristics of the adhesive-dentin bond using differential staining.
Dentin bonding using the total-etch method has been cl aim ed to be technique-sensitive . The aim of this study is to examine the effect of acid-etch variations on the dentin demineralization and interfacial structure of the adhesive-dentin bond using a differential staining technique . Single Bond adhesive with 35 % phosphoric acid gel was used . The occlusal one-third of the crown was removed from 60 extracted , unerupted human third molars . Smear layers were created by abrading the dentin with 600 grit SiC under water for 30 s. The prepared teeth were r and omly assigned to four groups according to etching time ( Group 1 , 10 s ; Group 2 , 15 s ; Group 3 , 30 s ; Group 4 , 60 s ) . In each group , the etching gel was : ( i ) applied and spread to the dentin surface and left to st and undisturbed ; ( ii ) applied and gently agitated during etching ; ( iii ) applied without using dispensing tips for the syringe and left for the same period as above . After rinsing , the etched dentin was then treated with the adhesive per manufacturers ' instructions . 3 - 5 micro m thin sections of the adhesive/dentin ( a/d ) interface were cut with a microtome and stained with Goldner 's trichrome . Stained , thin sections from each prepared tooth were imaged with light microscopy . The depth and extent of dentin demineralization , and the a/d interdiffusion zone were clearly visible by this differential staining microtechnique . The thickness of the interdiffusion zone increased as a function of etching time . However , the etchant gel application methods have a significant influence on dentin demineralization . Although agitating acid gel facilitates the penetration and etching into dentin , it should not be recommended , especially for longer etching time . These results indicated that the etching technique has a large effect on the profile of both dentin demineralization and interfacial structure
No overall effect was revealed in the meta-analyses , meaning that no influence of the  ER or SE strategy on POS .
SIGNIFICANCE The type of adhesive strategy ( ER or SE ) for posterior resin composite restorations does not influence the risk and intensity of POS .
OBJECTIVES A systematic review and meta- analysis were performed on the risk and intensity of postoperative sensitivity ( POS ) in posterior resin composite restorations bonded with self-etch ( SE ) and etch- and -rinse ( ER ) adhesives .