Should silane coupling agents be used when bonding brackets to composite restorations? An in vitro study.
The purpose of this in vitro study was to determine a safe and efficient method for bonding brackets to resin composite (RC), permitting the brackets to tolerate shear forces and allowing removal without causing surface damage to the aesthetic restoration. The shear bond strength (SBS) of 60 brackets bonded to silanated and non-silanated RC surfaces were compared. A Bis-GMA containing orthodontic adhesive system was used to bond stainless steel upper lateral incisor brackets to 60 composite discs, half of which had surface treatment with a silane coupling agent. SBS testing was performed with an Instron universal testing machine. After debond, the bracket base and corresponding RC discs were examined under a stereomicroscope and analyzed using the Adhesive Remnant Index (ARI). Non-parametric tests (Mann-Whitney U) indicated significant differences between the two groups (P < 0.009). Lower bond strengths were found for the silanated group implying that silane agents may be an unnecessary step. However, both groups had a clinically acceptable mean SBS [silanated group = 13.1 megapascals (Mpa), non-silanated group = 19.4 MPa]. Bond failure occurred at the bracket-adhesive interface in both groups. There would appear to be no advantage in using a silane agent when bonding metal orthodontic brackets to filled RCs.
Eslamian
Ladan
L
Department of Orthodontics, Dental Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. l-eslamian@dent.sbmu.ac.ir
Ghassemi
Amir
A
Amini
Fariborz
F
Jafari
Alireza
A
Afrand
Mona
M
D000134:Acid Etching, Dental; D000180:Acrylic Resins / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent; D003799:Dental Stress Analysis / Q000295:instrumentation; D006801:Humans; D008422:Materials Testing; D016910:Orthodontic Brackets; D010756:Phosphoric Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D012821:Silanes / Q000737:chemistry*; D013193:Stainless Steel / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors; D014867:Water / Q000737:chemistry
D000180:Acrylic Resins; D003188:Composite Resins; D003722:Dental Alloys; D003764:Dental Materials; C513708:Heliomolar; D010756:Phosphoric Acids; D011140:Polyurethanes; D019279:Resin Cements; D012821:Silanes; D014867:Water; D013193:Stainless Steel; D017438:Bisphenol A-Glycidyl Methacrylate; C030242:phosphoric acid