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Purpose: The objectives of this investigation were to evaluate the effect of disinfection on surface quality and dimensional stability of more recent, reformulated vinylpolysiloxane (VPS) and polyether (PE) materials., Methods: Using ANSI/American Dental Association (ADA) specification 19 protocols, 50 impressions of stainless steel dies were made with each material. Ten impressions of each material were randomly assigned to a treatment group: (1) no disinfectant; (2) 10-minute dual phenol immersion; (3) 1-hour dual phenol; (4) 10-minute sodium hypochlorite (NaOCl); and (5) 1-hour NaOCl. Impression surface quality immediately after disinfection was categorized as smooth/shiny, matte, or wrinkled/sticky. Dimensional stability was evaluated by measuring dimensional accuracy according to specification 19 after 24-hour, 1-week, and 2-week storage at ambient laboratory conditions., Results: The PE material surface quality was significantly affected (Pearson Chi-square, p

Purpose: The most frequent cause of clinical failure of resin-bonded fixed partial dentures is a debonding at the metal-cement interface. The purpose of this in vitro study was to compare the tensile bond strengths of 3 different alloy-surface treatments when cemented to human enamel with a resin cement., Materials and Methods: Cylinders of a nickel-chromium-beryllium (Ni-Cr-Be) and a gold-palladium (Au-Pd) alloy were fabricated and assigned to different surface treatment groups as follows: Group 1: Ni-Cr-Be, chemically etched; Group 2: Au-Pd, airborne particle-abraded and tin-plated; and Group 3: Au-Pd, airborne particle-abraded and treated with the Alloy Primer (Kuraray Co, LTD, Osaka, Japan). The cylinders were bonded to the enamel surfaces of extracted, human third molars and stored in normal saline at 37 degrees C for 48 hours. The tensile bond strength of 21 specimens from each group was measured on a Universal Testing Machine (Instron, Canton, MA). Three failed specimens of each group were evaluated using scanning electron microscopy and energy dispersive spectroscopy., Results: Statistically significant differences (p <.05) were found between all 3 treatment groups. The mean tensile bond strengths (+/- the standard error of mean) recorded as follows: Group 1: 10.6 MPa (+/-1.3), Group 2: 0.9 MPa (+/-0.2), and Group 3: 13.4 MPa (+/-1.0). Specimens from groups 1 and 3 revealed a trend towards mixture of cohesive, within the resin cement, and adhesive failures at the metal-cement interface. Group 2 specimens exhibited primarily adhesive failures at the metal-cement interface., Conclusions: The tensile bond strength of Au-Pd alloy specimens was significantly increased with the Alloy Primer., (Copyright 2001 by The American College of Prosthodontists.)

The purpose of this study was to examine the interactive effects of alcohol and salience of social cues (personality traits) on allocation of attention in the intoxicated male social drinker. It was expected that inebriated subjects would preferentially attend to high threat relative to low threat information contingent on the information's personal relevance. Seventy-six participants received either alcohol or a placebo, or were in a control condition, and were given the opportunity to attend to personally salient or nonsalient positive, negative, and neutral information. Intoxicated participants viewed negative traits longer than did nonintoxicated subjects and attended to these traits longer in the salient than in the nonsalient condition. Findings are compared to the attention allocation model, and their implications for alcohol-mediated cognitive processes are discussed.