Effect of different adhesive systems and laser treatment on the shear bond strength of bleached enamel.
OBJECTIVE
This study determined the shear bond strength of a nanohybrid composite resin to bleached enamel immediately or 15 days later using different adhesive systems and laser application.


METHODS
One hundred and forty enamel specimens were prepared from human molar teeth and bleached either with 16% carbamide peroxide (CP) or 30% CP according to the manufacturer's (Vivastyle/Vivadent) recommendations. After bleaching treatments specimens were divided into two groups according to the treatment time of the adhesive procedures: immediately or 15 days after the bleaching treatments. The four groups were then divided into five subgroups due to the surface treatments: using a two-step self-etching adhesive (AdheSe, Ivoclar Vivadent G, Schaan, Liechtenstein) or a two-step etch and rinse adhesive (Excite, Ivoclar Vivadent G, Schaan, Liechtenstein) and application of laser prior to adhesive procedures or not. After adhesive procedures nanohybrid composite resin cylinders of 4 mm x 2 mm (Tetric Evo Ceram/Vivadent) were bonded to the enamel surfaces. All specimens were subjected to shear bond strength test after thermocycling and 24h of storage in water. Data were analyzed statistically.


RESULTS
Mann-Whitney U-test analysis showed no significant difference in the mean bond strength values of enamel bleached with either 16% CP or 30% CP (p>0.05). There was no difference between the groups bonded immediately or 15 days after bleaching (p>0.05). Application of the etch and rinse adhesive after 15 days showed the highest bond strength values, whereas self-etching adhesive and laser application showed the lowest values in both bleaching treatments.


CONCLUSIONS
The results suggested that following the bleaching treatments, the use of etch and rinse adhesive system may provide higher bond strengths than self-etching adhesive and laser application.
Gurgan
Sevil
S
Hacettepe University, School of Dentistry, Department of Restorative Dentistry, Sihhiye 06100, Ankara, Turkey.
Alpaslan
Tugba
T
Kiremitci
Arlin
A
Cakir
Filiz Yalcin
FY
Yazici
Esra
E
Gorucu
Jale
J
D000134:Acid Etching, Dental; D000180:Acrylic Resins / Q000737:chemistry; D000077463:Carbamide Peroxide; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003743:Dental Enamel / Q000187:drug effects / Q000528:radiation effects / Q000648:ultrastructure*; D003764:Dental Materials / Q000737:chemistry; D004338:Drug Combinations; D006801:Humans; D053844:Lasers, Solid-State; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry; D016877:Oxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D010545:Peroxides / Q000008:administration & dosage / Q000627:therapeutic use; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014073:Tooth Bleaching / Q000379:methods*; D014508:Urea / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use; D014867:Water / Q000737:chemistry
D000180:Acrylic Resins; C489662:AdheSE cement; D003188:Composite Resins; D003764:Dental Materials; D004338:Drug Combinations; C420130:Excite cement; D008689:Methacrylates; D016877:Oxidants; D010545:Peroxides; D019279:Resin Cements; C501891:Tetric EvoCeram; D014867:Water; D000077463:Carbamide Peroxide; D014508:Urea