Effect of HEMA on bonding of Er:YAG laser-irradiated bovine dentine and 4-META/MMA-TBB resin.
The purpose of this study was to evaluate the priming effect of 2-hydroxyethylmetaclirate (HEMA) following acid treatment on resin bonding to prototype Er:YAG laser-irradiated dentine. Extracted bovine dentine following laser irradiation was acid treated by aqueous solution of 10% citric acid (10-0) or 10% citric acid/3% ferric chloride (10-3), and additionally treated with 35% HEMA. Pre-treated dentines were bonded to the polymethyl-methacrylate (PMMA) rod with 4-META/MMA-TBB resin (Super Bond C & B) and miniaturized dumbbell-shaped bonded specimens were prepared. These specimens profiled for tensile bond testing and fractured surfaces were observed by scanning electron microscopy (SEM). Cross-sections of resin-dentine interface were also examined. The HEMA treatment following acid conditioned by 10-3 or 10-0 for both laser-irradiated and non-irradiated dentines was significantly higher than that without HEMA treatment. SEM view of a fractured specimen showed some cohesive failure in cured resin, but almost all of the fractured surface shows boundary failure between the penetrated resin and underlying dentine. A cross-sectional view of the interface showed a very thick hybrid layer between the hybridized dentine and underlying dentine. It was concluded that HEMA treatment following acid conditioning provided a slightly higher bond strength for both the Er:YAG laser-irradiated and non-irradiated dentines. However, the bond strength of Er:YAG laser irradiated dentine was significantly lower than that of the non-irradiated dentine.
Kameyama
A
A
The Third Department of Conservative Dentistry, Tokyo Dental College, Chiba, Japan. kameyama@tdc.ac.jp
Kawada
E
E
Amagai
T
T
Takizawa
M
M
Oda
Y
Y
Hirai
Y
Y
D000818:Animals; D001896:Boron Compounds; D002417:Cattle; D001840:Dental Bonding; D003804:Dentin / Q000528:radiation effects* / Q000648:ultrastructure; D003806:Dentin Permeability / Q000528:radiation effects; D017220:Dentin-Bonding Agents; D007834:Lasers; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D008768:Methylmethacrylates; D008855:Microscopy, Electron, Scanning; D010777:Photochemistry; D019904:Polymethyl Methacrylate; D019279:Resin Cements; D013718:Tensile Strength
D001896:Boron Compounds; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D008768:Methylmethacrylates; D019279:Resin Cements; C005044:hydroxyethyl methacrylate; D019904:Polymethyl Methacrylate; C049495:Super-bond