Benchmark dose calculations of methylmercury-associated neurobehavioural deficits

Prenatal methylmercury exposure is associated with neuropsychological deficits in Faroese children at age 7 years. Lower confidence bounds of benchmark doses (BMDLs) have now been calculated. With the cord-blood mercury concentration as the dose parameter, a logarithmic dose-response model tended to show a better fit than a linear dose model for the attention, language and verbal memory tests. The lowest BMDLs averaged approximately 5 microgram/l cord blood, which corresponds to a maternal hair concentration of approximately 1 microgram/g. However, most BMDLs for hair mercury concentrations were higher. Thus, the results of the benchmark calculations depend on the assumed dose-response model.

Alternate framework designs for removable partial dentures

STATEMENT OF PROBLEM

The removable partial denture is usually less appreciated than the fixed partial denture by both patients and prosthodontists. This negative attitude could be due to problems associated with the wearing of a removable partial denture and concern essentially with comfort, esthetics, masticatory function, occlusal stability, and maintenance of oral hygiene. Such problems could be limited if treatment planning is made carefully, according to simplified and logical principles for framework design, and if oral hygiene and the fit of the dentures are regularly controlled.

PURPOSE

This article reviews the factors associated with the prognosis of treatment with removable partial dentures. Furthermore, the article describes framework design applied in different clinical situations and compares them with more conventional designs. It seems important to consider a framework design that privileges comfort, esthetics, and oral hygiene rather than to follow mechanical rules that are entirely theoretical and have not been confirmed scientifically or clinically.

[Antifungal varnish in the treatment of denture stomatitis]

The efficacy of a single-dose application of miconazole varnish in the treatment of denture stomatitis was compared with miconazole gel applied three times/day for 15 days. Among 288 wearers of complete dentures 50 patients severely affected by denture stomatitis and heavily colonized by Candida, were selected. The patients were assigned randomly to two groups: a miconazole varnish group and a gel group. All patients were examined 7 times: before starting the treatment (day 0); during treatment (day 3, 7 and 14); after treatment (day 21, 28 and 35). At each examination a photograph of the palatal mucosa was obtained and quantitative cultures of Candida from the lesions and the fitting denture surface were performed. At day 14 the inflammation was reduced to the same degree in the two groups of patients. A comparison of the antifungal effect, i.e. reduction of the yeast score, showed no significant difference between the two groups. Maximum reduction of the number of yeasts was obtained at day 14. From that moment, recolonization started; thus, about 60% of the treated patients whether it was with the gel or the varnish was positive of Candida by day 35. In conclusion, the present study showed no difference in the clinical and antifungal effect of a single-dose application of miconazole varnish compared with miconazole gel. The varnish seemed to be better with respect to the posology as the total dose of miconazole is minimal and only one application is necessary. Treatment with the miconazole varnish seems particularly indicated in debilitated and non-cooperative patients suffering from Candida-associated denture stomatitis.

[Lichen planus. Clinical diagnosis, epidemiology and pathogenesis]

Lichen planus is a common mucocutaneous disease of unknown etiology which was initially described a century ago. The specific etiology remains unclear. A number of relationships between lichen planus and other conditions have been noted. The lesions occur most commonly on the buccal mucosa. Gingival involvement occurs in approximately 10% of reported cases. The appearance of lichen planus is extremely variable which leads to confusion with other clinically similar disease entities.

Inhibition of leukocyte migration by the agarose plate technique. Application to antigen from Candida albicans and Fusobacterium nucleatum

Leukocyte migration inhibition by antigen from Candida albicans and Fusobacterium nucleatum was studied in man by means of the direct leukocyte migration agarose technique (LMAT). Antigens were prepared by prolonged ultrasonication and were added to the leukocyte cultures in the original as well as in the concentrated solutions. Significant inhibition of migration with a 10-fold concentrated solution of candida antigen was demonstrated in subjects showing apositive intracutaneous reaction to candida. With the fusobacterial antigen, inhibition of migration or stimulation of migration were demonstrated in subjects with slight peridontal inflammation. A 5-fold increase in the concentration of fusobacterial antigen resulted in increased stimulation of migration or inhibition of migration. Preincubation of the leukocytes with puromycin abolished both inhibition and stimulation of migration by candidal or fusobacterial antigen. The study confirms that it is important to study dose-related effects when applying the LMAT to test cell-mediated immunity. The study is in support of stimulation of migration being an immunologic reaction.