Effect of adhesive materials on shear bond strength of a mineral trioxide aggregate.
OBJECTIVE
To compare the shear bond strength (SBS) and fractography between mineral trioxide aggregate (MTA) and glass-ionomer cement (GIC) or resin composite (RC) after varying MTA setting time intervals.


METHODS
MTA was mixed and packed into standardized cavities (4 mm diameter x 3 mm depth) in acrylic blocks. RC with 37% H₃PO₄ and type 2 (etch and rinse) adhesive, or conventional GIC was bonded to the exposed MTA sample surfaces after 10-minute, 24-hour, 72-hour and 30-day MTA setting intervals (n = 10/group, eight groups). Samples were stored (37°C, 24 hours, 100% humidity) before SBS testing and statistical analysis (ANOVA, Tukey LSD, P < 0.05). Fractography was undertaken using stereomicroscopy for all samples and three random samples/group by using SEM.


RESULTS
Significant differences between all groups were found (P= 0.002). SBS of RC:MTA (Max 5.09 ± 1.79 MPa) was higher than the SBS of GIC:MTA (Max 3.74 ± 0.70 MPa) in 24-hour, 72-hour and 30-day groups except in the 10-minute MTA setting time groups, where SBS of GIC:MTA was higher. There was a significant effect of time on SBS of RC: MTA (P = 0.008) and no effect on SBS of GIC:MTA (P = 3.00). Fractography revealed mixed (adhesive/cohesive) failures in all groups; in RC:MTA groups there was a decrease in adhesive failure with time in contrast to the GIC:MTA groups.
Ahmed
A
Ali
Avijit
A
Banerjee
Francesco
F
Mannocci
D000134:Acid Etching, Dental / Q000379:methods; D000268:Adhesiveness; D017607:Aluminum Compounds / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004338:Drug Combinations; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D010756:Phosphoric Acids / Q000737:chemistry; D033081:Shear Strength; D017640:Silicates / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
D017607:Aluminum Compounds; D017610:Calcium Compounds; D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; C439808:Fuji IX GP Fast; D005899:Glass Ionomer Cements; C551012:N'Durance composite resin; D010087:Oxides; D010756:Phosphoric Acids; D017640:Silicates; C532387:XP-Bond; C086631:mineral trioxide aggregate; C030242:phosphoric acid