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Platinum films electrodeposited from 10 mM H2PtCl6 have been probed using scanning electron microscopy (SEM) and ex situ scanning tunneling microscopy (STM) to examine morphological changes produced when Pb(II) is added to the deposition solution. Deposition was carried out potentiostatically at −250 and −1000 mV (vs Ag/AgCl) from solutions containing three different Pb(II) concentrations:  0, 0.05, and 0.4 mM. The presence of Pb(II) produced an extremely rough, spiky morphology on the nanometer scale and suppressed dendritic aggregation on the micrometer scale. These observations are interpreted in terms of Pb(II) counteracting enhanced surface diffusion of Pt atoms resulting from interaction between them and chloride ions at the solution/electrode interface.

Background: Topical corticosteroids are often used in the treatment of psoriasis, but long-term use may be associated with serious adverse events such as tachyphylaxis or atrophy of the skin. Tazarotene, a new topical retinoid, has demonstrated significant clinical benefits but can cause mild to moderate local irritation. Objective: We evaluate whether a combination treatment of topical tazarotene and a topical corticosteroid would increase efficacy while reducing the incidence of local adverse events associated with a topical retinoid. Methods: Three hundred patients enrolled in an investigator-masked study were randomly assigned to 1 of 4 treatment groups: tazarotene 0.1% gel in combination with placebo cream, or with a low-, mid-, or high-potency corticosteroid cream, for 12 weeks of treatment and a posttreatment follow-up at week 16. Results: Tazarotene 0.1% gel in combination with a mid- or high-potency corticosteroid, when compared with tazarotene plus placebo cream, achieved significantly greater reductions in scaling, erythema, and overall lesional severity, and a decreased incidence of adverse events. Conclusion: All tazarotene combinations (including tazarotene plus placebo) were highly effective in rapidly reducing the severity of psoriasis. Combining tazarotene with a topical corticosteroid increased efficacy while reducing the incidence of local adverse events. (J Am Acad Dermatol 1998;39:590-6.)

A recently released dentine adhesion promoter, based on a HEMA/maleic acid primer, was found to bond exceptionally well to dentine (14.1 MPa) if the adhesion promoter layer was applied thickly enough. Air inhibition of the promoter layer during its initial cure was seen to reduce the bond strength by a half if the promoter layer was air-thinned prior to curing. The adhesion promoter was found to greatly enhance the bond strength of composite to glass ionomer, removing the necessity to acid etch the glass ionomer prior to applying the composite. The failure of the composite/glass ionomer bond was always within the glass-ionomer cement itself, with the higher bond strengths resulting in a greater incidence of oblique cracks at 45 degrees to the bond surface than had been previously observed

Background: A new class of topical receptor-selective acetylenic retinoids, the first of which is tazarotene, has been developed. Objective: Our purpose was to compare the safety, efficacy, and duration of therapeutic effect of 12 weeks of once-daily tazarotene 0.1% and 0.05% gel with that of twice-daily fluocinonide 0.05% cream in the treatment of patients with plaque psoriasis. Methods: Three hundred forty-eight patients with plaque psoriasis were enrolled and 275 patients completed a multicenter, investigator-masked, randomized, parallel-group clinical trial. Results: Both tazarotene gels were as effective as fluocinonide in reducing plaque elevation after 1 week of treatment, and tazarotene 0.1% gel was similar to fluocinonide in reducing scaling of trunk/limb lesions at all study weeks except week 4. Tazarotene 0.1% gel was similar to fluocinonide in reducing scaling of knee/elbow lesions at weeks 8 and 12. Fluocinonide had a significantly greater effect on erythema than tazarotene at weeks 2 through 8. However, treatments were not significantly different at week 12, and tazarotene demonstrated significantly better maintenance of therapeutic effect after cessation of therapy. Conclusion: Tazarotene 0.1% and 0.05% gels were safe and effective in the treatment of mild-to-moderate plaque psoriasis.(J Am Acad Dermatol 1998;38:705-11.)