Orthodontic adhesives

A single component light-curable orthodontic adhesive comprising:

• a curable resin monomer component, said curable resin monomer component comprising at least bisphenol A diglycidyl ether dimethacrylate, ethoxylated trimethylopropane triacrylate, ethoxylated bisphenol A dimethacrylate, and triethylene glycol dimethacrylate;
• a quaternary curing initiator system comprising:
• camphorquinone,
• bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide,
• octyldimethylaminobenzoate, and
• 1,1′-azobis(cyanocyclohexane);
• and
• filler,
• wherein the single component light-curable orthodontic adhesive will not harden to a crusty consistency for about 70 seconds to about 100 seconds when exposed to a halogen operatory exam lamp positioned at a distance providing 10,000±50 lux output for an approximately 2 mm×2 mm×20 mm extruded sample of the adhesive on a white background;
• and wherein the single component light-curable orthodontic adhesive is capable of exhibiting a shear bond strength, when applied to an etched and sealed bovine tooth, of greater than 7 MPa within 60 seconds after light curing for a duration of 2 seconds to 5 seconds, as measured using a halogen curing light having an 850 mW/cm2 output in the 400-505 nm range to irradiate the adhesive applied to an etched and sealed bovine tooth.

A single component light-curable orthodontic adhesive comprising:

• a curable resin monomer component including more than one different curable resin monomer;
• a quaternary curing initiator system comprising:
• camphorquinone,
• bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide,
• octyldimethylaminobenzoate, and
• 1,1′-azobis(cyanocyclohexane);
• and
• filler,
• wherein the single paste light-curable orthodontic adhesive has a working time (W) to curing time (C) ratio (W/C) of at least 10 to 30,
• wherein said working time is expressed as a multiple of a five second interval that is visually determined as a point at which an approximately 2 mm×2 mm extruded sample of the single component light-curable orthodontic adhesive sufficiently hardens to a crusty consistency and undergoes a brittle fracture when cut in approximately 2 mm sections under a halogen operatory exam light positioned to provide 10,000±50 lux at the extruded sample on a white background,
• wherein said curing time is a duration of exposing the single component light-curable orthodontic adhesive to a curing light that is necessary to effect a shear bond strength greater than 7 MPa within 60 seconds after the single component light-curable orthodontic adhesive is applied to an etched and sealed bovine tooth,
• wherein said curable monomer component includes at least four of the following:
• bisphenol A diglycidyl ether dimethacrylate, ethoxylated bisphenol A dimethacrylate, ethoxylated trimethylopropane triacrylate, pyromellitic glycol dimethacrylate, triethylene glycol dimethacrylate, glycidyl methacrylate, and glycerol dimethacrylate, and
• wherein the curable resin monomer component comprises at least
• 5 wt % to 20 wt % of bisphenol A diglycidyl ether dimethacrylate,
• 5 wt % to 20 wt % of ethoxylated trimethylopropane triacrylate,
• 15 wt % to 30 wt % of ethoxylated bisphenol A dimethacrylate, and
• 40 wt % to 60 wt % of triethylene glycol dimethacrylate, wherein wt % is based on the total weight of the curable resin monomer component.