Microtensile bond strengths of glass ionomer (polyalkenoate) cements to dentine using four conditioners.
OBJECTIVE
The purpose of this study was to measure the microtensile bond strengths of three glass ionomer cements to dentine (Photac-Fil Quick; Fuji II LC; Fuji IX GP) using four different conditioners (Ketac Conditioner; Dentin Conditioner; Cavity Conditioner; and an experimental conditioner, K-930).


METHODS
Superficial occlusal dentine of extracted human third molars was exposed, finished with wet 600-grit silicon carbide paper, and each of the above glass ionomer cements bonded using the four conditioners according to the manufacturers' instructions. After 24h in tap water at 37 degrees C, the teeth were sectioned to obtain 3-4 bar-shaped specimens. Ten specimens were prepared for each group and shaped to an hour-glass form of (1.2+/-0.02)mm diameter. The specimens were mounted in a jig and stressed in tension at a crosshead speed of 1mm/min until failure. The mean bond strengths were calculated and compared using one-way ANOVA and LSD tests, and the fracture modes were examined by scanning electron microscopy.


RESULTS
Mean microtensile bond strengths for Photac-Fil Quick were not significantly different from Fuji II LC for each of the conditioners used. However, the bond strengths for Photac-Fil Quick were significantly greater than Fuji II LC when no conditioner was applied. Mean microtensile bond strengths of conditioned specimens of Fuji II LC were significantly greater than non-conditioned specimens. Mean microtensile bond strengths of non-conditioned specimens of Fuji IX GP were not significantly different from conditioned specimens. The fracture mode of all specimens demonstrated mostly cohesive failure within the cement.


CONCLUSIONS
The use of surface conditioners resulted in improvement in bond strength of Fuji II LC, while Photac-Fil Quick and Fuji IX GP showed no difference.
Tanumiharja
M
M
School of Dental Science, The University of Melbourne, 711 Elizabeth St, Melbourne, Australia. m.tanumiharja@pgrad.unimelb.edu.au
Burrow
M F
MF
Tyas
M J
MJ
D000180:Acrylic Resins / Q000737:chemistry*; D000704:Analysis of Variance; D017554:Carbon Compounds, Inorganic; D001840:Dental Bonding / Q000379:methods*; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008964:Molar, Third; D012117:Resins, Synthetic / Q000737:chemistry; D017655:Silicon Compounds; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors; D014867:Water
D000180:Acrylic Resins; D017554:Carbon Compounds, Inorganic; D017220:Dentin-Bonding Agents; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; C081144:Photac-Fil; D012117:Resins, Synthetic; D017655:Silicon Compounds; C110713:fuji IX; D014867:Water; C006903:carbopol 940; C022088:silicon carbide