Effect of surface conditioning and restorative material on the shear bond strength and resin-dentin interface of a new one-bottle nanofilled adhesive.
OBJECTIVE
To determine the effect of different combinations of surface conditioning (DeTrey Conditioner 36, NRC, no etching) and restorative materials (Dyract AP, Spectrum TPH) on the shear bond strength of Prime and Bond NT to enamel and dentin, and to characterize the resin-dentin interface produced by these combinations.


METHODS
Shear bond strength was tested on 30 enamel and 30 dentin flat labial surfaces of extracted bovine teeth. The enamel and dentin specimens were randomly assigned to six groups of five teeth each and treated using different combinations of surface conditioners and restorative materials with Prime and Bond NT. Scanning electron microscope (SEM) observation of argon-ion-etched specimens was done to evaluate the resin-dentin interface.


RESULTS
The type of surface conditioning and restorative material had significant effects on dentin bond strengths. Etching the dentin prior to application of Prime and Bond NT significantly increased bond strength and caused formation of a hybrid layer for Spectrum TPH. For Dyract AP, dentin etching generally did not improve bond strength despite the formation of a hybrid layer. On enamel, Prime and Bond NT had consistently high bond strengths on etched specimens.


CONCLUSIONS
The results showed that Dyract AP and Spectrum TPH, when used with Prime and Bond NT have different bonding mechanisms and the effect of surface conditioning on their shear bond strength differs. Clinicians should be aware of these effects in order to optimize bonding.
Department of Operative Dentistry, School of Dentistry at Niigata, The Nippon Dental University, 1-8 Hamauracho, Niigata 951-8580, Japan. mitchsu@edsamail.com.ph
Michelle C
MC
Sunico
Koichi
K
Shinkai
Vicente O
VO
Medina
Manabu
M
Shirono
Norihiro
N
Tanaka
Yoshiroh
Y
Katoh
D000134:Acid Etching, Dental; D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D020770:Compomers; D003188:Composite Resins; D001840:Dental Bonding; D003743:Dental Enamel; D003804:Dentin; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents; D008422:Materials Testing; D008689:Methacrylates; D008855:Microscopy, Electron, Scanning; D011109:Polymethacrylic Acids; D011897:Random Allocation; D019279:Resin Cements; D033081:Shear Strength; D017640:Silicates; D013499:Surface Properties
D020770:Compomers; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C088486:Dyract; D008689:Methacrylates; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D019279:Resin Cements; D017640:Silicates; C420128:Spectrum composite resin; C113300:TPH hybrid