A comparative study of oral acetylsalicyclic acid and metoprolol for the prophylactic treatment of migraine. A randomized, controlled, double-blind, parallel group phase III study.

This study was a multinational, multicentre, double-blind, active controlled phase III trial designed to investigate efficacy and safety of 300 mg acetylsalicyclic acid (ASA) (n = 135) vs. 200 mg metoprolol (n = 135) in the prophylaxis of migraine. In total 270 (51 male and 219 female) patients, aged 18-65 years, suffering between two and six migraine attacks per month were recruited. The main objective was to show equivalence with respect to efficacy, defined as a 50% reduction in the rate of migraine attacks. A run-in phase was carried out with placebo for 4 weeks, followed by a 16-week drug phase. In both treatment groups the median frequency of migraine attacks improved during the study period, from three to two in the ASA group and from three to one in the metoprolol group; 45.2% of all metoprolol patients were responders compared with 29.6% with ASA. Medication-related adverse events were less frequent in the ASA group (37) than in the metoprolol group (73). The findings from this trial show that metoprolol is superior to ASA for migraine prophylaxis but has more side-effects. Acetylsalicylic acid is better tolerated than metoprolol. Using a strict responder criterion ASA showed a responder rate comparable with the placebo rate in the literature.

Periodic evaluation of the occlusal vertical dimension of maxillary dentures from the wax trial denture through 48 hours after polymerization.

PURPOSE: This study measured the effects of commercial resin type on maxillary complete dentures with monoplane teeth by periodically comparing the occlusal vertical dimension of the polymerized dentures with the baseline, wax trial denture fiducial measurements. MATERIALS AND METHODS: Commercially available compression-molded, injection-molded, and fluid poly(methyl methacrylate) resins, as well as one compression-molded methyl acrylate ester copolymer, were evaluated. Ten dentures were fabricated from each resin using monoplane teeth. The occlusal vertical dimension at the articulator pin was measured at the wax denture stage for each specimen, and changes in occlusal vertical dimension for each denture were evaluated at a simulated laboratory remount, and at 0, 3, 6, 24, and 48 hours after a simulated clinical remount. Repeated measures analysis of variance (alpha = 0.05) and post hoc one-way factorial analysis of variance and Scheffe's F-Tests for each resin group were performed using ranks of raw data. RESULTS: Changes in the maxillary denture mean occlusal vertical dimensions were recognized throughout the evaluation periods compared with the wax-denture baseline, and time was a significant influence on displacement (p = .0001). Only the compression-molded poly(methyl methacrylate) dentures exhibited a mean laboratory remount occlusal vertical dimension that was significantly greater than the mean wax denture measurement, and all resin systems exhibited occlusal error that was significantly less than the laboratory remount measurements at 48 hours. At 48 hours, all resin groups exhibited mean occlusal vertical dimension changes that were less than 1 mm compared with the wax denture. Only compression-molded poly(methyl methacrylate) dentures exhibited a mean 48-hour clinical remount measurement that was statistically similar to the mean wax denture occlusal vertical dimension. CONCLUSIONS: Individual maxillary dentures from all resin types and at all intervals exhibited dimensional change. At the last evaluation period, the compression-molded poly(methyl methacrylate) showed no change in mean occlusal vertical dimension from baseline, whereas remaining groups exhibited occlusal vertical dimensions significantly less than baseline.

Wear of visible light-cured restorative materials and removable partial denture direct retainers.

PURPOSE: This study measured the in vitro wear of visible light-cured restorative materials and removable partial denture direct retainers. MATERIALS AND METHODS: An aluminum test die was produced by replicating the facial contours of an extracted human molar (model). The replica's cervical contour was modified by placement of a restorable Class V cavity preparation. The test die became a fixed component of a testing apparatus. The restorative materials tested were Z100 (fine particle filled resin composite), Silux Plus (microfilled resin composite), and Photac-Fil (hybrid glass ionomer). Cast round, half round, I bar, and wrought-wire retainers were designed to engage a 0.254-mm undercut. Caliper measurements of the wear of restorative materials were made at intervals during testing, and after 7,500 retainer placements and removals. The measurements of material- and retainer-wear were subjected to ANOVA and Tukey tests. RESULTS: Generally, retainers with round profiles caused less wear of the restorative materials than those featuring flat contact surfaces. Wear of the materials ranged from 14 +/- 5.5 microns (Silux Plus by cast round) to 70 +/- 10.0 microns (Photac-Fil by cast half round). Mean wear of retainers, however, ranged only from 2 +/- 4.5 microns for six of 12 possible retainer-material pairings up to 12 +/- 4.5 microns (cast half round by Z100). CONCLUSIONS: Regardless of their design features, the direct retainers of this study exhibited little wear when paired with any of the restorative materials. Overall, material wear appeared to be greater than retainer wear by a factor of five. When paired with practically any retainer type, the hybrid glass ionomer (Photac-Fil) exhibited more wear than either of the two resin composites (Z100 or Silux Plus). Although not established clearly, retainers with round profiles (wrought-wire and cast round) appeared to produce less wear of restorative materials than their I bar and cast half round counterparts.

The light-cured composite restoration: an adjunct to removable partial prosthodontics.

An integral part of fabricating a removable partial denture is preparing the mouth to accommodate the design of the prosthesis and the patient's clinical presentation. When the morphology of the abutment tooth does not correspond to the design requirements, altering its form by either enameloplasty or restorative procedures is indicated. Research and clinical experience have shown that composite restoration is a suitable adjunct to preparing the mouth for removable partial dentures.

Influence of circadian periodicity on reproducibility of centric relation records for edentulous patients.

Complete dentures were made for 30 edentulous patients. The patients were divided into three groups and the dentures were remounted twice on the same day in a Vericheck instrument. The dentures for 10 patients were remounted twice in the morning (AM group), for 10 patients twice in the afternoon (PM group), and for 10 patients once in the morning and again in the afternoon (AM-PM group). Changes in position between the interocclusal records were measured on both the right and left horizontal X and Y axes and the sagittal Y and Z axes. No significant changes were noted when horizontal versus sagittal or right versus left positions were compared, but significant changes were noted between the AM versus AM-PM time groups, and between the PM versus AM-PM time groups.

The relationship between the width of the mouth, interalar width, bizygomatic width, and interpupillary distance in edentulous patients.

The width of the mouth, interalar width, bizygomatic width, and interpupillary distance were measured in edentulous patients. The widths varied widely, even when the population was separated into groups by sex and/or race. When mean values were studied, black men differed significantly from black women, white women, and white men in interalar and bizygomatic widths; white women differed from the other groups in all widths. No correlation was found between the widths for the population as a whole, nor when the population was further divided into race, sex, or group. When artificial teeth were chosen for eight randomly selected patients using a method recommended for each of the widths, the same mold was dictated by two methods for seven patients, and by three methods for five patients.

Three-dimensional stability of new denture base resin systems.

Ten maxillary dentures were constructed on standard-sized casts in each of four acrylic resins. Uniform placement of the artificial teeth and thickness of the base were maintained by use of a silicone rubber mold. Metal shot was luted in preselected positions to the dentures and the land of the cast. Frontal, lateral, and occlusal radiographs were made of the dentures at time intervals of (1) before processing, (2) after processing, (3) immediately after removal from the cast, and (4) 30 days later. Study of the radiographs revealed significant variations in position of the metal shot from the before-processing baseline within each group of dentures and significant differences between groups of dentures.

[Organic nitrates and prostaglandins in the cardiovascular system]. / Organische Nitrate und Prostaglandine im kardiovaskulären System.

The beneficial effect of organic nitrates in acute myocardial ischemia is commonly explained by their hemodynamic actions, especially the dilatation of venous capacitance vessels. Recent studies have shown an inhibition of platelet function by organic nitrates ex vivo but not in vitro. Antiplatelet activities of organic nitrates might represent an additional mechanism, independent of vascular actions which might eventually involve stimulation of prostacyclin formation by the vessel wall. In vitro experiments on isolated coronary artery preparations have demonstrated stimulation of PGI2 as well as inhibition of platelet thromboxane synthesis by a number of organic nitrates. Optimal stimulation requires the presence of a free nitro group in the molecule at a particular steric position and can be suppressed by a number of inhibitors, including corticosteroids, indomethacin and methylene blue. Administration of the organic nitrate teopranitol to healthy volunteers is associated with depressed platelet secretion ex vivo which is not seen with the compound in vitro. It is concluded that further clinical elucidation of the PGI2-related mechanism in the action of organic nitrates in patients appears to be both necessary and useful.

A study of the position of the parotid papilla relative to the occlusal plane.

This study determined that a fairly constant relationship exists between the parotid papilla and the occlusal plane. An additional finding was that this relationship may not be the same on each side of the mouth. Race and sex differences were not significant.

[Inhibition of platelet aggregation and thromboxane formation by the calcium antagonist nisoldipine following a single oral dose of 10 mg. A double-blind study in healthy probands]. / Hemmung der Plättchenaggregation und Thromboxanbildung durch den Calcium-Antagonisten Nisoldipin nach einer oralen Einmaldosis von 10 mg. Eine Doppelblind-Crossover-Studie bei gesunden Probanden.

The influence of the calcium antagonist nisoldipine on collagen-induced platelet aggregation and platelet thromboxane formation was studied ex vivo in healthy male volunteers in a double-blind, placebo-controlled crossover design. Measurements of general haemodynamics, immunoreactive 6-oxo-prostaglandin F1 alpha and thromboxane B2 ex vivo and collagen-induced (0.6 and 2.5 micrograms/ml) platelet aggregation were performed immediately before (time 0), 0.5 h, 1 h and 2 h after ingestion of 10 mg nisoldipine or an identical placebo tablet. Compared with the control response at time 0, administration of nisoldipine resulted in a significant inhibition of both low-collagen-induced platelet aggregation and formation of immunoreactive thromboxane B2 at time 0.5 h. There were no changes in heart rate or systolic blood pressure but a significant decrease in diastolic blood pressure by nisoldipine at 1 h. No such change was obtained with placebo and there were also no alterations with nisoldipine in platelet aggregation and thromboxane formation after stimulation by high-dose collagen at this or any other time of the study. The data demonstrate a platelet-inhibitory potential of nisoldipine in healthy men which is probably related to an increased resistance of the platelet membrane against foreign stimuli.