A comparison between the shear bond strength of brackets bonded to glazed and deglazed porcelain surfaces with resin-reinforced glass-ionomer cement and a bis-GMA resin adhesive.
OBJECTIVE
This study compared the shear bond strength of a light-cure resin-reinforced glass-ionomer cement with a bis-GMA light-cure resin system in the bonding of stainless steel brackets to glazed and deglazed porcelain surfaces.


METHODS
Porcelain surfaces were divided into 4 groups: group 1, deglazed porcelain surfaces with Transbond XT, group 2, glazed porcelain surfaces with Transbond XT; group 3, deglazed porcelain surfaces with Fuji Ortho LC; and group 4, porcelain surfaces with Fuji Ortho LC. Microetching with 50-microm aluminum oxide for 2 seconds at a distance of 5 mm deglazed the porcelain surfaces in groups 1 and 3. All brackets were bonded to the porcelain surfaces using the same procedure and light-cured for 40 seconds with a visible light. All samples were thermocycled between 5 degrees C and 55 degrees C for 300 cycles before testing for shear bond strength with a universal testing machine.


RESULTS
The analysis of variance showed no significant difference (P < .05) among the 4 groups; ie, group 1, 10.12 MPa; group 2, 7.00 MPa; group 3, 6.78 MPa; and group 4, 11.15 MPa. The F test also failed to demonstrate any statistical difference among the groups.


CONCLUSIONS
Conditioning the porcelain surfaces with 37% phosphoric acid immediately followed by a nonhydrolyzed silane coupling agent resulted in clinically adequate bond strength when using either a composite resin or a resin-reinforced glass-ionomer cement. Microetching of these porcelain surfaces apparently offers no bonding advantage.
Lifshitz
Abraham B
AB
Department of Orthodontics, College of Dentistry, Intercontinental University, Mexico City, México. braces@prodigy.net.mx
Cárdenas
Marianela
M
D000134:Acid Etching, Dental; D000180:Acrylic Resins; D000537:Aluminum Oxide / Q000737:chemistry; D000538:Aluminum Silicates; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry*; D001840:Dental Bonding; D045662:Dental Etching; D003776:Dental Porcelain / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D016910:Orthodontic Brackets; D010756:Phosphoric Acids / 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; D013696:Temperature
D000180:Acrylic Resins; D000538:Aluminum Silicates; C095451:Fuji Ortho LC; D005899:Glass Ionomer Cements; D010756:Phosphoric Acids; D019279:Resin Cements; D012821:Silanes; C477790:Transbond XT; D003776:Dental Porcelain; D013193:Stainless Steel; D017438:Bisphenol A-Glycidyl Methacrylate; C030242:phosphoric acid; D000537:Aluminum Oxide