On the basis of available evidence , MTA presented good marginal adaptation to dentine walls .
This systematic review analysed the literature comparing marginal adaptation of mineral trioxide aggregate ( MTA ) with other filling material s in root-end cavities .
The effect of smear layer on the push-out bond strength of root canal calcium silicate cements.
INTRODUCTION The aim of this study was to evaluate the effect of smear layer removal on the push-out bond strength between radicular dentin and three calcium silicate cements ( CSC ) in comparison with gutta percha and sealer . METHODS Eighty human anterior extracted teeth were decoronated , cleaned and shaped to size 50/0.05 apically and r and omly divided into 2 major groups : ( A ) smear layer preserved , and ( B ) smear layer removed using irrigation with 17 % EDTA . Roots within each major group were further divided into 4 subgroups according to the obturation material used : ( 1 ) ProRoot MTA , ( 2 ) Biodentine , ( 3 ) Harvard MTA , ( 4 ) Gutta percha and AH-plus sealer . Obturated roots were stored in synthetic tissue fluid for 7 days to allow maximum setting of the root filling material s. Three 2-mm-thick slices were obtained from each root at different section levels ( coronal , middle , apical ) . The canal diameters and slice thickness were measured , and the adhesion surface area for each slice was calculated . Push-out bond strength test was carried out using a universal testing machine . The bond failure mode was assessed under an optical microscope at 40 × . RESULTS The mean push-out bond strength in groups 1A , 2A and 3A were 7.54 ( ±1.11 ) , 7.64 ( ±1.08 ) and 8.79 (±1.55)MPa respectively , while those for groups 1B , 2B and 3B were 6.58 ( ±1.13 ) , 6.47 ( ±1.08 ) , 7.71 (±1.81)MPa , respectively . In the gutta percha and sealer groups the push-out bond strength means were : 1.98 ( ±0.48 ) and 2.09 (±0.51)MPa in the preserved and removed smear layer groups respectively . The push-out strength values were significantly reduced when the smear layer was removed in the CSC groups ( P<0.05 ) while no significant difference was detected in the gutta percha and sealer groups . CONCLUSIONS Based on the conditions of this ex vivo study , it can be concluded that smear layer removal is detrimental to the bond strength between calcium silicate cements and dentin
On the basis of available evidence , MTA presented good marginal adaptation to dentine walls .
This systematic review analysed the literature comparing marginal adaptation of mineral trioxide aggregate ( MTA ) with other filling material s in root-end cavities .