The Long-Term Host Response to Liquid Silicone Injected during Soft Tissue Augmentation Procedures: A Microscopic Appraisal

BACKGROUND Silicone has a long history of use as a soft tissue filler.
MATERIALS AND METHODS As a contribution to the clarification of the role and fate of this material when used as a filler in soft tissue augmentation techniques, 35 skin biopsies were examined by light microscopy. These biopsies were obtained from target areas where liquid silicone had been injected in 25 patients between 1 and 23 years prior, for the correction of depressed scars on the face.
RESULTS The microscopic study revealed in 100% of the cases the continued presence, in significant amounts, of the silicone previously injected into the target areas, where it failed to elicit any significant adverse reaction.
CONCLUSION Owing to its high permanence and to its inertness, reflected by the lack of any adverse reaction to its presence in the target site, silicone should be regarded as a valuable filler, at least for the correction of small depressed facial scars.     

Re-examining crude coal tar treatment for psoriasis

Two separate, double-blind, randomized, half-and-half body comparisons, each involving 20 in-patients with psoriasis, were conducted to compare the effect of different concentrations of crude coal tar in yellow soft paraffin. The therapeutic effect of 1% crude coal tar used twice daily for 10 days was significantly less than that achieved with an incremental regimen starting at 5% and increasing by 5% every second day to a maximum of 25%. No such difference was seen when a steady concentration of 5% was compared with the same incremental regimen. We conclude that there appears to be no benefit from exceeding a concentration of 5% crude coal tar in yellow soft paraffin in the treatment of patients with psoriasis and that the plateau in the dose-response curve for the action of crude coal tar in psoriasis begins at a point between 1 and 5%.