Two-part self-adhering dental compositions

1. A method for providing a two-part paste/paste dental composition to a tooth surface comprising the steps of:

(I) etching a tooth surface with an etchant and/or priming the tooth surface with a primer/adhesive,

(II) mixing two pastes of a two-part paste/paste composition to form a mixed composition immediately prior to application to the tooth surface,

(III) applying the mixed composition to the tooth surface, and

(IV) hardening the mixed composition,

wherein the two-part paste/paste composition comprises a first paste comprising

(a) at least one polymerizable monomer with a polymerizable group selected from the group consisting of an acrylate, a methacrylate, and a vinyl group;

(b) a substituted thiourea selected from the group consisting of 1-(2-pyridyl)-2-thiourea and 1-(2-tetrahydrofurfuryl)-2-thiourea; and

(c) a finely divided filler having a mean particle size of less than 50 microns; and a second paste comprising

(d) at least one acidic compound containing at least one acidic moiety selected from the group consisting of

where R is an alkyl or aryl group;

(e) at least one polymerizable monomer without any acidic group with a polymerizable group selected from the group consisting of an acrylate, a methacrylate, and a vinyl group;

(f) a hydroperoxide compound with at least one hydroperoxide group attached to a tertiary carbon; and

(g) a finely divided filler having a mean particle size less than 50 microns.

2. The method of claim 1 wherein the two part composition further comprises at least one component selected from the group consisting of a photo-initiator, a stabilizer, a solvent, and combinations thereof.

3. The method of claim 1 wherein the filler is selected from the group consisting of inorganic metal, salt, oxide, nitride, silicate glass, aluminosilicate glass, aluminoborosilicate glass, fluoroaluminosilicate glass, quartz, colloidal silica, precipitated silica, zirconia-silica, polymeric filler, polymerized composite filler with inorganic particles, and combinations thereof.

4. The method of claim 1 wherein the acidic compound is a polymerizable monomer/polymer with at least one ethylenically unsaturated group selected from the group consisting of an acrylate, a methacrylate, and a vinyl group.

5. The method of claim 4 wherein the acidic polymerizable monomer is selected from the group consisting of hydroxyethylmethacrylate phosphate (HEMA-P), glyceryldimethacrylate phosphate (GDM-P), bis(hydroxyethylmethacrylate) phosphate (Bis(HEMA)-P), methacryloyloxydecyl phosphate (MDP), phenyl methacryloxyethyl phosphate (phenyl-P), and dipentaerythritol pentaacrylate phosphate (PENTA-P).

6. The method of claim 1 wherein the hydroperoxide compound is selected from the group consisting of t-butyl hydroperoxide, t-amyl hydroperoxide, p-diisopropylbenzene hydroperoxide, cumene hydroperoxide, pinane hydroperoxide, p-menthane hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, and combinations thereof.

7. The method of claim 1 wherein each part of the two part composition is packaged in a syringe.

8. The method of claim 1 wherein each part of the two part composition is packaged in a syringe in a dual syringe assembly.

9. The method of claim 8 wherein each syringe in the dual syringe assembly has an opening and a static mixer is attached to the openings and provides a homogeneous mixture upon dispensing the mixed composition from an exit opening of the mixer.

10. The method of claim 1 wherein the composition is applied to a tooth surface as at least one of a restorative composition, an orthodontic composition, or an endodontic composition.

11. The method of claim 1 wherein the composition is applied to a tooth surface as at least one of a filling material, a cement, a liner/base, a pit/fissure sealant, or an adhesive composition.