Abstract Objective To evaluate the effects of surface moisture (wet or dry) and storage (24 h or 3 months) on the microtensile bond strength (BS) of resin/dentin bonds mediated by two water/ethanol ...based adhesives Single Bond, 3M-ESPE, (SB) and Opti Bond Solo Plus, Kerr, (OB), and two acetone-based adhesives, One Step, Bisco, (OS) and Prime&Bond NT, Caulk/Dentsply, (PB). Materials and methods Flat dentin surfaces were polished with 600-grit SiC paper, etched with 35% phosphoric acid for 15 s and rinsed for 20 s. Half the surface was maintained moist and the other half was air-dried for 30 s. Each adhesive was applied simultaneously to both halves, left undisturbed for 30 s and light-cured. Four-mm resin build-ups were constructed incrementally. After storage in water at 37 °C for 24 h, slabs were produced by transversal sectioning and trimmed to an hourglass shape (0.8 mm2 ). Half of the specimens were tested in tension at 0.6 mm/min immediately after trimming and the other half after 3 months of water storage. Data were analyzed by two-way ANOVA and SNK for each material. Results Both moisture and storage affected BS to dentin, and was material-dependent. Dry bonding affected mostly the acetone-based adhesives. Larger reductions in bond strength were associated with dry bonding after 3 months of water storage. Significance Wet bonding resulted in more stable bonds over 3 months of water storage for most of the materials tested.
Abstract Objectives The application of an electric field has been shown to positively influence the bonding of dentin bonding systems (DBS) by improving adhesive impregnation into dentin. However, ...the mechanism responsible for this phenomenon has not been completely elucidated. The aim of this study was to clarify the effects of pH, matrix ionic strength, and applied voltage on the migration of commonly used DBS monomers in a model matrix (agarose gel). Methods Some common monomers examined were bis-GMA (2,2-bis4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl propane); HEMA (2-hydroxyethyl methacrylate); 2-MP (bis2-(methacryloyloxy) ethyl phosphate); TCDM di(hydroxyethyl methacrylate) ester of 5-(2,5,-dioxo tetrahydrofurfuryl)-3-methyl-3-cyclohexenyl-1,2-dicarboxylic acid; and TEGDMA (triethylene glycol dimethacrylate). Agarose gels poured into a horizontal 10-well electrophoretic cell were used to mimic the collagen fibrils of the dentin organic matrix. The role of pH, matrix ionic strength, and voltage on monomer migration was assayed by modifying the experimental conditions. Results Results of experiments performed at pH 3.1, 6.3, 8.5, and 12.3; at low, medium, and high ionic strength; and at 50 and 100 V clearly showed that DBA monomer migration toward both the anode and the cathode can be affected by each of these parameters. Significance Migration of acrylic monomers toward the anode or cathode can be achieved as desired by selective choice of pH, ionic strength, and applied voltage. Additional studies are needed to evaluate the synergistic effects of DBS monomer blends on migration in an electric field.
Part I was an overview of the role and function of proteoglycans and glycoproteins in the pulpo–dentin complex; part II will focus on enzymes, serum proteins, and growth factors. This review will ...discuss current knowledge regarding matrix metalloproteinases (MMPs), cathepsins, serum proteins, and growth factors in dentin and the related dentin–pulp complex in an attempt to better understand their nature, role, and function in the dentin extracellular matrix (ECM) environment. Dentin formation in physiological and pathological conditions has been widely studied. However, the regulation and involvement of non‐collageneous enzymes, serum proteins, and growth factors are still not completely elucidated. MMPs, a family of 23 endopeptidases in humans, are collectively capable of degrading virtually all ECM components, and their specific tissue inhibitors (TIMPs: tissue inhibitors of matrix metalloproteinases) participate in organo‐ and morphogenesis, physiological tissue turnover, and pathological tissue destruction. Similarly, the lysosomal cysteine proteinases (cathepsins) are capable of degrading ECM proteins such as collagen, laminin, fibronectin, and proteoglycans. These enzymes are implicated in a variety of pathological conditions, especially in diseases involving tissue re‐modeling states. Dentin also contains serum‐derived proteins (such as albumin, immunoglobulins, and transferrin), and a variety of growth factors in the mineralized ECM are available for release during demineralization or other injury. A detailed description of the components of the above‐mentioned dentin non‐collageneous proteins will be summarized in this literature review.
