Leucite content of selected dental porcelains.

Leucite is a major crystalline component of dental porcelains. The presence of tetragonal leucite in dental porcelains increases their coefficients of thermal expansion due to its high coefficient of thermal expansion (20-25 x 10(-6)/degrees C). This is particularly useful for those porcelains designed for bonding to precious metals and nickel alloys. The purpose of this study was to determine the leucite content of selected commercial dental porcelains in relation to their coefficient of thermal expansion values. The weight fraction of leucite was determined with quantitative x-ray diffraction using copper as an internal standard. Coefficient of thermal expansion values were determined using a thermal dilatometric analyzer. Five commercial body porcelains were studied. Leucite was not detected in samples of Vitadur N and Duceram LFC. An ANOVA showed that there was a significant difference in the weight fraction of leucite for Silhouette, Ceramco II, and Optec HSP porcelains. Linear regression revealed a correlation (R = 0.91) between weight fraction of leucite and the coefficient of thermal expansion for those samples containing leucite. Duceram LFC, which is recommended by the manufacturer for use with metals and leucite-containing porcelains, had no detectable leucite although the coefficient of thermal expansion was found to be 13.2 +/- 0.4 x 10(-6)/degrees C at 25-472 degrees C. A low glass transition temperature contributed to the high average coefficient of thermal expansion value.

Clinical experience with biliopancreatic bypass and gastrectomy or selective vagotomy for morbid obesity.

In 1980 Scopinaro described biliopancreatic bypass for the treatment of obesity. This procedure was aimed at selective malabsorption. The authors used Scopinaro's procedure in 33 patients, but in 17 they modified it by doing selective vagotomy with closure of the duodenum in continuity instead of a subtotal gastrectomy. Eighteen months after the operation, 88% of the patients had what the authors considered was a good to excellent result, that is a loss of more than 25% of the patient's initial weight. Morbidity of many kinds was encountered but most was self-limiting or easily corrected by medical means. From their experience the authors conclude that biliopancreatic bypass as a procedure for the treatment of morbid obesity should continue to be performed and evaluated.

Long-term results of hyperselective vagotomy for duodenal ulcer.

Although considered by many as the operation of choice in the treatment of duodenal ulcer, hyperselective vagotomy without drainage is not unanimously accepted because little is known about its long-term efficiency in preventing ulcer recurrence. The long-term results of 203 patients with duodenal ulcer, treated by hyperselective vagotomy between 1974 and 1983 at the Hôpital Laval, are reported. Patients were followed at yearly intervals and questionnaires were used to determine whatever benefits they perceived. The procedure was found to be a safe one with an uncomplicated postoperative course. The overall recurrence rate was 12% over a mean follow-up of 64 months. Recurrences may occur 5 or more years after surgery. The operative technique is important in preventing recurrence. Dissection of the last 6 cm of esophagus lowered the recurrence rate at 5 years from 21% to 9%. Only four patients required reoperation. The majority of recurrences consisted of a single episode, the ulcer being easily controlled by short-course medical treatment. The authors found that 94% of patients were satisfied with the results of the operation.

Short-term antibiotherapy for peritonitis: prospective, randomized trial comparing cefotaxime-metronidazole and clindamycin-tobramycin.

The combination of cefotaxime and metronidazole has been suggested for the treatment of peritonitis. We compared their effectiveness with that of tobramycin and clindamycin. Since antibiotics have most of their beneficial effect within a few days a four day course was used and a randomized trial was undertaken. The effectiveness of the 4-day course was 86% and no difference was seen between the two groups of the study.

[Pleural effusion indicator of pancreatitis]. / Epanchement pleural révélateur de pancréatite.

The presence of a pleural effusion in patients with pancreatitis is a common marginal occurrence. On rare occasions the pleural effusion not only is abundant, recurrent, hemorrhagic and contains a high concentration of amylase, but presents as the only manifestation of an otherwise undiagnosed or obscure pancreatitis. Thus it presents a difficult diagnostic and therapeutic problem. The authors report such a case and review the literature in which 49 cases have been reported in the past 10 years. Pancreatomediastinopleural fistula is usually visualized and seems to be the basic fault in most cases. Thoracic drainage will relieve the patient and dry up the effusion in one third of cases. Otherwise pancreatic resection is usually required. Internal or external drainage of the mediastinopleural component by laparotomy is not difficult. Pleural sequelae are minimal in most cases.

Experience with hyperselective vagotomy in patients with duodenal ulcer.

Hyperselective vagotomy is a relatively recent surgical procedure used for the treatment of duodenal ulcer. We report excellent results in 98 consecutive patients during the last four years. After a mean follow-up period of 2.2 years, the results, according to the classification of Visick, are excellent in a large number of patients. There was a significant gain in body weight in a majority of the patients. The recurrence rate for an ulcer is only 4.5 per cent. There is a significant reduction of basal acid output of 63 per cent, maximal acid output of 46.8 per cent and postinsulin acid output of 73.7 per cent.