The plane of fracture and shear bond strength of three composite inlay systems.

Composite inlays have been introduced to overcome some of the problems encountered with direct placement techniques. However, some doubt has been expressed about the strength of the bond between the inlay surface and the composite luting cement due to the decreased number of C = C bonds remaining following supercuring of the inlay. This study investigated the bond strength of three composite inlay systems to etched bovine enamel and recorded the plane of fracture of the samples.

Prognostic importance of social and economic resources among medically treated patients with angiographically documented coronary artery disease.

Objective: To evaluate the hypothesis that diminished social and economic resources impact adversely on cardiovascular mortality in patients with coronary artery disease.

Design: Inception cohort study of patients undergoing cardiac catheterization from 1974 through 1980 and followed up through 1989.

Setting: Tertiary care university medical center.

Ultraviolet radiation, solar dermatosis, and cutaneous neoplasia in beagle dogs.

Beagle dogs that were part of a life span study of the effects of low-level ionizing radiation during development were evaluated for the incidence of skin neoplasia and solar dermatosis. A total of 991 dogs up to 14 years of age were examined. The dogs were housed in gravel-based, outdoor pens with doghouses in a high-altitude, high-sunshine level environment.

Effect of noncutting tipped instruments on the quality of root canal preparation using a modified double-flared technique.

Fifty-one extracted human first molar teeth with intact crowns and mature root apices were divided into three groups. Root curvature was determined. One of the root canals in the mesial root of lower molars, or the mesiobuccal root in maxillary molars, was prepared in one of three ways.

RU486 in depression.

RU486 is a synthetic glucocorticoid antagonist. The authors used RU486 to examine the hypothesis that the elevated plasma cortisol and ACTH in patients is due to suprahypophyseal stimulation of the anterior pituitary. Seven patients and matched controls were studied before and after the administration of RU486.

Radiation carcinogenesis in dogs irradiated during prenatal and postnatal development.

To evaluate the lifetime hazards of ionizing radiation exposure, 1680 beagles received whole-body, 60-Cobalt gamma exposures or sham-exposures during development. Eight groups of 120 dogs each received mean doses of 16 or 83 cGy at 8 (preimplantation), 28 (embryonic), or 55 (late fetal) days postcoitus (dpc), or 2 (neonatal) days postpartum (dpp). One group of 120 dogs received 83 cGy at 70 dpp (juvenile), and one group of 240 dogs received 83 cGy at 365 dpp (young adult).

Shear bond strength of Mirage Bond to enamel and dentin.

This study determined the shear bond strength of resin composite to bovine enamel etched with Mirage Bond primer containing 2.5% nitric acid. These results were compared with 37% orthophosphoric acid gel.

Compartmentalization within the nucleus: discovery of a novel subnuclear region.

Antibodies to a set of structurally related autoantigens (p23-25) bind to a previously uncharacterized, large structural domain in the nucleus of a variety of human cell types. This subnuclear domain is visible by phase contrast alone as a region of decreased density after several different fixation protocols. The morphology of this region changes dramatically during the cell cycle and we have given it the name PIKA (for polymorphic interphase karyosomal association) based on preliminary evidence that the PIKA proteins may be associated with chromatin.

Effect of impression tray design and impression technique upon the accuracy of stone casts produced from a putty-wash polyvinyl siloxane impression material.

This study examined the accuracy of stone casts produced from impressions taken in stock polycarbonate trays, some of which had been strengthened with autopolymerizing polymethyl methacrylate resin. Three techniques were used to make the impression of an acrylic master model of the mandibular arch on which two extracoronal preparations for bridgework and one intracoronal inlay preparation had been carried out. Each preparation had been indented with a reference point for later measurement.

Effect of Mirage Bond primer on microleakage of resin composite restorations.

This in vitro study assessed the microleakage of Class V restorations using Mirage Bond (NPG-PMDM) with a hybrid light polymerized resin composite. Restorations were inserted in cavities prepared in extracted human premolars using either bulk or incremental packing and with or without an intermediary unfilled resin. The enamel margin of each tooth was etched only with the primer.

Working group recommendations: methods for geriatric evaluation and management research.

Methodological issues relating to multi-site studies of inpatient geriatric evaluation and management units were the focus of this working group's deliberations. The group favored a randomized clinical trial in which the inpatient geriatric evaluation and management unit was coupled with outpatient geriatric care. Inclusion of a broad spectrum of patients stratified according to risk for poor hospital outcomes was proposed in order to obtain information on the types of patients that would be most likely to benefit.

The effects on the dental pulp of a composite resin and two dentine bonding agents and associated bacterial microleakage.

The pulpal reaction associated with a composite resin alone and composite resin used in conjunction with two dentine bonding agents was studied. Class V cavities were prepared on the labial surfaces of the canine teeth of 18 male ferrets. After acid etching of the enamel margins, the cavities were restored with either a composite resin alone or in combination with one of two dentine bonding agents, Scotchbond and Gluma.

The effect of bonding agent and fissure sealant on microleakage of composite resin restorations.

The purpose of this study was to assess, in vitro, the microleakage of Class V composite resin restorations following sealing of the margins with a fissure sealant or the resin component of a dentinal bonding agent, and to compare it to the microleakage of an unsealed control group. All groups of teeth showed some degree of leakage at the gingival margin. Statistical analysis showed that there was significantly less leakage when the fissure sealant (P less than .

The effect of post space preparation on the apical seal of root fillings using chemically adhesive materials.

The effect on the apical seal of root filling teeth with two sealer cements that reacted chemically with tooth structure was studied in vitro. In addition, apical leakage of teeth obturated with these materials and subsequently prepared to accept a post was tested. Ninety single-rooted teeth with mature apices were prepared chemomechanically by the stepback technique using files and copious irrigation with 2.

Fast feedback regulation of ACTH by cortisol.

1. Fast feedback regulation of ACTH by cortisol has not been well studied in humans. The authors studied the existence and characteristics of fast feedback regulation in normal humans.

Role of serotonin in hypothalamo pituitary adrenal axis escape from dexamethasone suppression.

1. The authors investigated the role of serotonin in the hypothalamo pituitary adrenal escape from depression. 2.

In vitro assessment of the microleakage around preventive resin (laminate) restorations.

The purpose of this study was to evaluate in vitro, the microleakage of laminate restorations using two resin systems and the influence of etching and curing regimen on the leakage. A total of 135 extracted, human third molars with similar occlusal dimensions were chosen. Cavities were prepared and the teeth were then separated into nine groups of fifteen teeth each.

Cardiovascular response to unilateral electroconvulsive therapy.

Few studies have examined the cardiovascular response to pulse unilateral electroconvulsive therapy (ECT) performed using modern techniques. In this study of 30 patients (mean age 62 years) with major depression, we determined the effects of pulse unilateral ECT on cardiac work load using the rate-pressure product (RPP), a product of pulse and systolic blood pressure. The mean RPP across all ECT treatments increased by an average of 96% from pre-ECT baseline, with the maximal RPP occurring typically during the seizure.

The effects of dentine bonding agents on marginal leakage of composite restorations.

The aim of this study was to compare the effects upon marginal leakage of a number of dentine bonding agents: Gluma, Scotchbond, Topaz and an experimental material when used with a posterior composite resin, Occlusin. The results were also compared with composite used without a dentine bonding agent and with a glass ionomer, Chemfil II. Class V cavities with or without a bevelled cavo-surface margin were prepared in the buccal surfaces of extracted premolar teeth.

Effect of water temperature on the accuracy of stone casts recovered from addition-reaction elastomeric impression materials.

This study investigated the accuracy of casts produced by mixing dental stone with water at different temperatures. Consecutive impressions of an acrylic resin model of the mandibular arch, on which the occlusal surfaces of three teeth had been indented with reference points, were made in two poly(vinyl siloxane) impression materials using a one-stage technique. After 1 hour these were cast in one of two stones using water at temperatures of 18 degrees C, 20 degrees C, or 24 degrees C.

Isolation of a human epidermal cDNA corresponding to the 180-kD autoantigen recognized by bullous pemphigoid and herpes gestationis sera. Immunolocalization of this protein to the hemidesmosome.

Autoantibodies present in the sera of patients with bullous pemphigoid (BP) bind to the basement membrane zone of normal human skin and commonly recognize two epidermal proteins, the BP240 and BP180 antigens. Two BP antigen cDNA clones from a lambda gt11 human keratinocyte library have been identified on the basis of reactivity with a BP serum. The fusion protein (FP) produced by one clone immunoadsorbed autoantibodies, which specifically recognized the BP180 by antigen, showing no cross-reactivity with BP240 by immunoblot analysis.

Investigation into the apical leakage of root-filled teeth prepared for a post crown.

The effect of post canal preparation on the apical seal of endodontically treated teeth was studied in vitro. Single-rooted teeth with mature apices were prepared chemomechanically and obturated with gutta-percha and sealer using one of four techniques: cold lateral condensation, thermo-mechanical compaction, thermomechanical compaction as an adjunct to lateral condensation (hybrid technique), or lateral condensation using an electrically heated spreader, the Endotec. Forty-eight hours after obturation each group of 15 teeth was prepared to accept a post crown.