[Correlation between the position of the 1st molars and the 3-dimensional trajectory of anterior guidance]. / Etude de la corrélation entre la mise en place des premières molaires et les trajectoires tridimensionnelles du guide antérieur.

This study tries to demonstrate that there is a correlation between the anterior trajectories of the mandible, in the anterior-posterior and lateral directions, and the occlusal morphology of the first permanent molars. The clinical consequences are interesting for prosthetic treatments, in the rehabilitation of anterior and canine guidance, and for orthodontic treatments.

Absorbable Adams-DeWeese caval clip: an experimental study.

Adams-DeWeese caval clips have been shown to be effective in preventing pulmonary embolism. However, the use of Teflon clips constitutes a permanent solution for this transient risk. We tested an absorbable caval clip made of currently available synthetic biodegradable polymers in five female beagle dogs. The polymer used was PLA 96 containing 96% L lactic acid and 4% D lactic acid. After placement through a laparotomy, clips were routinely inspected and samples of the material were collected at regular intervals between 3 and 19 months postoperatively. The characteristics of absorption of PLA 96 in the retroperitoneal space were the same as those previously described in the literature. The clip retained its shape, rigidity, and effectiveness for 7 months. Complete degradation of the clip took between 18 and 19 months. Absorption did not cause a major inflammatory reaction and had no thrombogenic effect. Given the small number of animals studied, these results must be considered preliminary.

Liver transplantation in patients with a surgical portasystemic shunt.

Of 220 patients undergoing liver transplantation between March 1982 and April 1991, eighteen (8.1 percent) already had a surgical portasystemic shunt. Four patients had a distal splenorenal shunt, six a side-to-side portacaval shunt, three an end-to-side portacaval shunt, and five, a mesocaval shunt. The splanchnic venous system was assessed by Doppler ultrasound examination and angiography before liver transplantation. Perioperative mortality rate was higher but not significantly different from that observed in the population of patients without previous portasystemic shunt (33.3 percent versus 21.7 percent). Liver transplantation was particularly difficult in the six patients with a previous side-to-side portacaval shunt, in which the perioperative mortality rate was high (66.6 percent). Liver transplantation is feasible in patients with a previous portasystemic shunt but carries a higher risk. It is easier when no previous dissection of the hepatic pedicle has been done. Suppression of the shunt after revascularization of the graft must be performed in order to provide optimal venous flow to the hepatic graft.

[Nasal polyps and food intolerance: is there any correlation]. / Poliposi nasale e intolleranza alimentare: esiste una qualche correlazione?

Nasal polyposis is a relatively frequent disease of poorly known aetiopathogenesis. In this study the Authors have evaluated the relationship between nasal polyposis and food using elimination diet and the double-blind challenge test. Of twenty-two patients examined, 16 (72.8%) completed the study. Six out of 16 subjects improved when on diet and challenged with specific foods. Two patients were affected by food allergy and 4 by food intolerance. Physical evaluation of nasal polyposis showed an improvement in all 6 patients, while rhinomanometric evaluation showed an improvement in 4 out of 6 patients, after diet. Most patients had an alteration of immunological tests involving IgE or circulating immunocomplexes-mediated mechanism.

The post-auricular response. A single motor unit study.

In order to investigate the functional significance of the 'post-auricular response' (PAR), a study was performed on single motor unit (MU) responses recorded by a microelectrode inserted into the retroauricular muscle body. The great variability of the latency of single MUs and the presence of later responses rule out a direct motoneurone activation. Our findings suggest a synchronizing action of acoustic stimuli on the firing of some MUs already present at rest or activated by the train of clicks, with a latency greater than 70 msec. The amplitude of the PAR recorded by surface electrodes and by averaging techniques is connected to the number of MUs synchronized by acoustic stimulation.