gluma and triethylene-glycol-dimethacrylate

Bonding of a tooth fragment to the remaining tooth substance can restore crown fracture of an anterior tooth. In this study, sheep central incisors were used. The crowns were fractured transversely and the crown fragment was bonded to the remaining tooth structure. This technique involves acid etching, use of an experimental adhesive (Gluma+) and a BisGMA/TEGDMA resin. The mean fracture strength of the restored teeth was not significantly different from that of intact teeth when tested at a rather low crosshead speed (0.5 mm/min) but different and about 30% lower when tested at a higher crosshead speed (500 mm/min). In studies aiming to test resistance to forces which might cause trauma, it might be appropriate to use a high crosshead speed.

Topics: Acid Etching, Dental; Adhesives; Analysis of Variance; Animals; Bisphenol A-Glycidyl Methacrylate; Composite Resins; Dental Bonding; Dental Restoration, Permanent; Dental Stress Analysis; Glutaral; Incisor; Polyethylene Glycols; Polymethacrylic Acids; Regression Analysis; Resin Cements; Sheep; Stress, Mechanical; Tooth Crown; Tooth Fractures

The purpose of this study was to investigate on human dentin the relationships between, on the one hand, the wettability of five adhesive compounds, characterized by different solubility parameters delta, and on the other, the thickness of the resin impregnated dentin layer (RIL) and the shear bond strength (SBS). Cut dentin surfaces were treated with conditioners of pH 1.25, 3.6 or 7.4. Shear bond strength was measured on 20 specimens each. RIL was determined by scanning electron microscope on specimens fractured perpendicularly to the bonding interface. When resins with delta 32, 30 or 39 (MJ1/2/m3/2) were used RILs were consistently 4 microns and 1 micron on dentin pretreated with the two acidic conditioners. No clearly measurable RIL was shown after application of the conditioner with pH 7.4, and when resins with delta-values of 20 and 25 were applied. For the same adhesive no difference in SBS was found, when applied on the differently conditioned dentin sites. Resins with delta > 30 produced significantly higher SBS than the two adhesives with smaller delta.

Topics: Analysis of Variance; Bisphenol A-Glycidyl Methacrylate; Composite Resins; Dental Bonding; Dentin; Dentin Permeability; Dentin-Bonding Agents; Glutaral; Humans; Materials Testing; Methacrylates; Microscopy, Electron, Scanning; Polyethylene Glycols; Polymethacrylic Acids; Resin Cements; Surface Properties; Tensile Strength; Wettability

The aim of the present study was to investigate the effect of the solubility parameter of the intermediary resin in the Gluma system on the bonding to dentin. The solubility parameter of the resins was varied between 18.8 x 10(3) and 21.1 x 10(3) J(1/2)/m3/2 by varying the composition of the resin. The efficacy of the bonding system was determined by measurements of marginal gaps formed by polymerization contraction of a restorative resin in dentin cavities treated with the bonding system. The bonding system had maximum efficacy at a solubility parameter of the intermediary resin of delta = 20.0 x 10(3) J(1/2)/m3/2. This finding corroborates a concept of bonding to dentin that involves a mechanical interlocking by interpenetrating resins.

Topics: Analysis of Variance; Bisphenol A-Glycidyl Methacrylate; Composite Resins; Dental Bonding; Dental Cavity Preparation; Dental Cements; Dentin; Glutaral; Humans; Methacrylates; Polyethylene Glycols; Polymethacrylic Acids; Solubility; Surface Properties