Aim: This study was to test the effect of a new hydrophilic monomer including two carboxylic acid groups, on shear bond strength of an experimental one-bottle dentine bonding system.
Method & Materials: This study is based on experimental and observation technique. Ninety human sound premolar teeth were divided by six groups. In each group, a flat level of dentine in the buccal surface of teeth is provided and was etched by phosphoric Acid (37%) for 15 seconds. An experimental bonding system based on Aceton/Alcohol solvent was provided as a control group and then different concentration 5%, 10%,15%, and 20% of BTDMA hydrophilic monomer was added. These experimental bonding systems and also a commercial bonding system [single Bond (3m)] as a golden sample was applied by a wet bonding technique on the deminerilized dentine surface of samples, then a composite cylinder of Z100 (3.2x2mm) was bonded to dentin. After one week of storage in distilled water (24C), shear bond strength of the sample was measured by instron machine with chisel blade and with the speed of 0.5 millimeter per minute. The results were analysed by ANOVA and Tukey tests. Meanwhile thePH in the used systems was measured.
Results: Mean and standard deviation shear bond strength (Mpa) and the PH of all used samples were such as below: Base=17.77±4.1, ph=8.4, BTDMA5%=22.78±2.94, ph=5.4, BTDMA10%=27.36±2.41,ph=4.7,BTDMA15%=28.63± 3.69, ph=4.3, BTDMA 20%=25.39±3.52, ph=4.0, Single bond=24.95±3.52, ph=4.6. The results achieved by ANOVA and Tukey tests were analysed. Shear bond strength in the control group was in the least amount and has a significant difference with all examined group (P<0.05). The addition of BTDMA to the bonding system, caused an increase in the bond strength (P<0.05). The BTDMA 15% group with the highest mean of bond strength , showed a significant difference with all groups except the BTDMA 10% group. The addition of BTDMA monomer with 20% weight, caused the fall in the shear bond strength in comparison with BTDMA 15% group (P<0.05).
Conclusion: The addition of a certain pencetage of BTDAM monomer to the base bonding system caused the increase in the shear bond strength to dentine.
J Dent Sch 2004 21(Special Issue): 671