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Item Antigen binding properties of IgG and IgM antibody to bovine serum albumin(1971) Coligan, John E.Item Item Comparison of Tensile Bond Strengths of Glass Ionomer Cements Using Hydroxyapatite Coated and Uncoated Orthodontic Brackets(1993) Ng, Richard I. Cheng Hin; Hohlt, William F.; Moore, B. Keith; Oshida, Yoshiki; Garetto, Lawrence P.; Roberts, W. Eugene; Shanks, James C.The use of glass ionomer cements (GIC) in orthodontics as a bonding agent has been receiving considerable attention due to its favorable properties, ie., physico-chemical adhesion to enamel, fluoride leaching capabilities and less traumatic bonding procedure to tooth structure. GIC ability to bond to the hydroxyapatite (HA) in the tooth enamel was tested utilizing an HA coated bracket developed by American Orthodontics. This study compared in vitro tensile bond strengths of four dental adhesives: Ketac-cem™ (KC), Vitrebond™ (VB), Transbond™ (TB) or Unite™ (UN), when used to bond to HA coated brackets and non-HA coated brackets. Bovine incisors were divided into eight groups of 20 specimens each. Each group included either an HA coated or non-HA coated bracket and one of the four adhesives. The brackets are manufactured with a Tricalcium Phosphate (TPC) coating, which is converted to an HA coating by the addition of -OH during autoclaving. The coated and non-coated brackets were bonded to the bovine teeth, which were embedded in epoxy resin blocks to fabricate the testing specimen. All of the specimens were stored in distilled water at room temperature for two weeks. This was followed by thermocycling after which the specimens were returned to water storage for an additional two weeks. The specimens were tested in tension on an lnstron Testing Machine until bond failure occurred. Mode of bond failure was determined visually by light microscope. The mean tensile bond strengths for KC and VB were each significantly less (p< 0.05) than the other three materials, while UN and TB were not significantly different. KC was the weakest at 0.68± 0.31 MPa, while UN was the strongest, 4.38±0.84 MPa. When comparing the GIG alone, there was a significant difference (p<0.0001) between the VB and the KC. The resins were not significantly different from each other. Differences between coated and non-coated were significant at p<0.05 with the noncoated brackets having the higher strength. Adhesive failure at the bracket interface for the two bracket types showed no difference for KC. TB and UN showed this type of failure significantly more with the coated brackets (p<0.05), and VB showed the opposite and more failure with non-coated brackets (p<0.01). The tensile bond strength of GIG continues to be significantly less than those of existing resins. The bond failure also revealed a high degree of within group variability. Trends relating failure mode to tensile bond strength could not be established. Greater bond strengths with the coated brackets and the GIG were not shown; however in the case of VB, the tendency for the coated brackets to fail less frequently at the bracket adhesive interface shows some promise. Further studies of these coated brackets are still warranted.Item The effect of full-contour Y-TZP ceramic surface roughness on the wear of bovine enamel and synthetic hydroxyapatite : an in-vitro study(2011) Sabrah, Alaá Hussein Aref, 1984-; Bottino, Marco C.; Lund, Melvin R., 1922-; Cochran, Michael A. (Michael Alan), 1944-; Hara, Anderson T.; Cook, Norman Blaine, 1954-THE EFFECT OF FULL-CONTOUR Y-TZP CERAMIC SURFACE ROUGHNESS ON THE WEAR OF BOVINE ENAMEL AND SYNTHETIC HYDROXYAPATITE: AN IN-VITRO STUDY by Alaa Hussein Aref Sabrah Indiana University School of Dentistry Indianapolis, Indiana Full-contour yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) restorations have been advocated recently in clinical situations where occlusal/palatal space is limited, or to withstand parafunctional activities. The objectives of this in-vitro study were to investigate the effects of different polishing techniques on the surface roughness of Y-TZP (Ardent Dental, Inc.) and to investigate the effects of different polishing techniques on the wear behavior of synthetic hydroxyapatite (HA) and bovine enamel. An in-vitro study was conducted by fabrication of 48 Y-TZP sliders (diameter = 2 mm × 1.5 mm in height) using CAD/CAM technique; then the samples were embedded in acrylic resin using brass holders. Samples were then randomly allocated into four groups according to the finishing/polishing procedure: G1-as-machined (n = 8), G2- glazed (n = 16), G3-diamond bur-finishing (Brasseler, USA) (n = 8) and G4- G3+OptraFine polishing kit (Ivoclar-Vivadent) (n = 16). Thirty-two sintered HA disks (diameter = 11 mm × 2.9 mm in height) and 16 bovine enamel samples with a minimum surface area of 64 mm2 were mounted in brass holders. Baseline surface roughness (Ra and Rq, in μm) were recorded using a non-contact profilometer (Proscan 2000) for all the samples. A two-body pin-on-disk wear test was performed for 25,000 cycles at 1.2 Hz in which the four zirconia groups were tested against HA, and only G2-glazed and G4- G3+OptraFine polishing kit (Ivoclar-Vivadent) were tested against bovine enamel. Vertical substance loss (μm) and volume loss (mm3) of HA were measured (Proscan). Zirconia height loss was measured using a digital micrometer. One-way ANOVA was used for statistical analysis. The results indicated that surface roughness measurements showed significant differences among the surface treatments with G1 (Ra = 0.84, Rq = 1.13 μm) and G3 (Ra = 0.89, Rq = 1.2 μm) being the roughest, and G2 (Ra = 0.42, Rq = 0.63 μm) the smoothest. The glazed group showed the highest vertical loss (35.39 μm) suggesting wear of the glaze layer, while the polished group showed the least vertical loss (6.61 μm). HA antagonist volume loss and vertical height loss for groups (G1, G2 and G3) were similar, while polished group (1.3 mm3, 14.7 μm) showed significant lower (p = 0.0001) values. Antagonist height loss and antagonist volume loss were significantly higher for bovine antagonist than for HA antagonist (197.6 μm/116.2 μm, and 28.5 mm3/17.7 mm3 for bovine against glazed/polished zirconia sliders, respectively) (p < 0.0001). From the results it can be concluded that glazed zirconia provided an initially smooth surface, but a significant increased antagonist wear compared with the polished surface was seen. Bovine enamel showed higher wear compared with HA, which suggested that more studies should be performed to validate the use of bovine enamel as a substitute for human enamel in wear studies.Item Evaluation of Tensile Bond Strength of a Fluoride-Releasing Resin Adhesive with Ceramic Brackets(1991) Lehman, David Alan; Roberts, W. Eugene; Moore, B. Keith; Shanks, James C.; Arbuckle, Gordon R.; Miller, James R.The increased attention to the esthetics of orthodontic appliances has led to the popularity of ceramic brackets in the last decade. Although the bonding of ceramic brackets has become predictably successful, the extreme brittleness of ceramics coupled with higher bond strengths has caused significant clinical problems in debonding and risk of enamel damage. This study evaluated an experimental bonding resin with different levels of fluoride concentration, linking the therapeutic property of long-term fluoride release to the benefit of decreased bond strength to ceramic brackets. Four groups of 40 Transcend™ ceramic brackets each were bonded to bovine teeth, using 0, 3, 6, and 12 percent fluoride concentrations. At two weeks, one-half of each group was tested for tensile bond strength in an lnstron machine. The remaining half were tested at six months. In the groups broken at two weeks, the bond strength peaked around 6 percent fluoride, but the three top groups were not significantly different. In the groups tested at six months, peak strength was observed at 3 percent fluoride and was significantly greater than the others. The overall mean at six months than at two weeks. The study found bond strength values in the range of 25-50 kg/cm2. Although minimum values have not been established, the low values reported in this study are likely to be within acceptable clinical limits. Following debonding, the mode of bond failure was determined by viewing enamel specimens and bracket bases under a light microscope. In all but one group, 95 percent of the bond failure occurred at the bracket base/adhesive interface. No bracket failure occurred and no enamel damage could be observed under the light microscope. In a parallel study of physical properties, Knoop hardness was measured at one hour, 24 hours, and six months, and compressive strength was tested at one week and six months. While physical properties generally decreased over the period of study, bond strength was significantly greater in the six-month group. The results of this study regarding the correlation of these properties to bond strength is inconclusive. In addition, results of fluoride-release data by SISCO Inc. indicate that the 12 percent group was shown to release greater than 10 μg/g/day at six months. This was comparable to amounts known to have the clinical benefit of reducing demineralization, and equaled or exceeded other commercially available fluoride-releasing adhesives. The results of this study indicate that a fluoride-releasing resin can release clinically significant amounts of fluoride ions, and still have adequate bond strength.Item Indiana State Board of Health Monthly Bulletin, 1909 Vol. 12 No. 11(1909) Barnard, H. E.