An in vitro study on restoring bond strength of a GIC to saliva contaminated enamel under unrinse condition.
OBJECTIVE
This study attempted to find a method of restoring the tensile bond strength of glass ionomer cement (GIC) to saliva contaminated enamel under unrinse condition.


METHODS
One hundred and thirty human non-carious permanent teeth were divided into two major groups. Either treatment with air drying, acetone, polyacrylic acid, maleic acid, tartaric acid, Scotchbond primer or no treatment at all was applied to both clean and saliva contaminated enamel surfaces prior to GIC placement. Samples were debonded in tension after 7 days of storage in water using a universal testing machine. Statistical analysis was performed using one-way ANOVA, Tukey's studentized range test and Wilcoxon's rank sums test to determine the significance of the difference of tensile bond strengths within and between the two major groups.


RESULTS
Bond strength of GIC to clean enamel was 2.46+/-0.79 MPa while the bond strength of GIC to wet contaminated enamel was significantly reduced to 1.28+/-0.32 MPa (p<0.01). However, the bond strengths were restored when the contaminated enamel surfaces were air-dried (2.19+/-0.38 MPa) or applied with either maleic acid (2.80+/-0.63 MPa) or Scotchbond primer (2.13+/-0.65 MPa) before placing GIC over the enamels.


CONCLUSIONS
Air drying, or application of maleic acid or Scotchbond primer to the contaminated enamel without rinsing prior to GIC placement can restore the tensile bond strength to a level similar to that of non-contaminated control.
Chen
C N
CN
Graduate Institute of Clinical Dentistry, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC.
Huang
G F
GF
Guo
M K
MK
Lin
C P
CP
D000096:Acetone / Q000737:chemistry; D000134:Acid Etching, Dental; D000180:Acrylic Resins / Q000737:chemistry; D000268:Adhesiveness; D000388:Air; D000704:Analysis of Variance; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure*; D003799:Dental Stress Analysis / Q000295:instrumentation; D017220:Dentin-Bonding Agents / Q000737:chemistry; D003890:Desiccation; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008298:Maleates / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010895:Pit and Fissure Sealants / Q000737:chemistry*; D019279:Resin Cements / Q000737:chemistry; D012463:Saliva / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D013499:Surface Properties; D013644:Tartrates / Q000737:chemistry; D013718:Tensile Strength; D014867:Water / Q000737:chemistry
D000180:Acrylic Resins; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D008298:Maleates; D010895:Pit and Fissure Sealants; D019279:Resin Cements; D012997:Solvents; D013644:Tartrates; D014867:Water; D000096:Acetone; C006903:carbopol 940; C041330:Scotchbond; C030272:maleic acid; C029768:tartaric acid