An in vitro comparison of coronal microleakage of three orifice barriers filling materials.
BACKGROUND
A coronal barrier in root-filled teeth is one of the most effective methods for prevention of coronal microleakage. The aim of this study was to compare coronal microleakage of three materials [light-cured glass-ionomer (GI), mineral trioxide aggregate (MTA), and composite resin] as coronal barriers.


METHODS
A total of 188 intact maxillary incisors were used. After instrumentation, all the canals were obturated with gutta-percha and lateral condensation technique using AH26 sealer. Then, the teeth were sectioned just apical to the cemento-enamel junction. The roots were randomly assigned to three experimental groups (n=56) and two negative and positive control groups (n=20). After placing the orifice barrier, the samples were immersed in 2% methylene blue solution for 2 weeks at 37°C. Then the teeth were longitudinally sectioned mesiodistally and dye penetration was measured under a stereomicroscope at ×10 magnification. Data were analyzed with one-way ANOVA and a post-hoc Tukey test.


RESULTS
The positive control group leaked significantly more than all the experimental groups (P=0.001). MTA exhibited less leakage than composite and GI (P=0.002) but no significant differences were found between GI and composite groups.


CONCLUSIONS
Immediate placement of a suitable intra-orifice barrier like MTA, before final restoration, may help minimize recontamination of the remaining apical gutta-percha.
Department of Endodontics, Dental School, Tabriz University of Medical Sciences, Tabriz, Iran ; Dental and Periodontal Research Center, Dental School, Tabriz University of Medical Sciences, Tabriz, Iran.
Hamidreza
H
Yavari
Mohammad
M
Samiei
Mahsa
M
Eskandarinezhad
Shahriar
S
Shahi
Marzieh
M
Aghazadeh
Yones
Y
Pasvey