880 Macker t -F i sher

Journal of the American Academy of

Dermatology

ard. Mercury in small quantities is found naturally in the human system. And the average mercury level found in the general public is more than 100 times lower than the level at which harmful effects are usually reported.

A r e n ' t some people allergic to mercury? In rare cases, a patient may experience an allergic

reaction to mercury, usually in the form of dermatitis or skin rash. To guard against this very remote possi- bility, the ADA recommends that dentists maintain a complete medical history for each patient. I f the patient is known to have such an allergy, the dentist may choose some other restorative material, something other than dental amalgam.

What other filling materials are available? Gold is often used to fill teeth, either in pure form

or alloyed with some metal or element other than mer-

cury. Some manufacturers are working to produce com- posite resins (plastics), which soon may be available as acceptable alternatives to dental amalgam. To date, however, these materials have not proved durable enough to withstand the great pressure generated by chewing. Dental researchers are constantly seeking safe, new methods for restoring decayed teeth. For most patients, though, dental amalgam remains a safe and effective material for filling cavities.

What is the "life span" of a dental amalgam? On the average, amalgams serve for at least ten

years, and very often they last considerably longer. Conditions in the mouth are constantly changing, and these changes affect dental materials and their function. Your fillings will last longer if you follow proper pro- cedures for home care and receive regular dental checkups.

A B S T R A C T S

Micro-organisms isolated from skin under wedding rings worn by hospital staff

Hoffman PN, Cook EM, McCarville MR, et al: Br Med J 290:206-207, 1985

Twenty of fifty nurses working on medical and surgical wards who permanently wore rings were found to have gram- negative organisms on the skin under the ring. Only one had gram-negative bacilli on a control site. Organisms isolated included Enterobacter (10), Klebsiella (5), A cinetobacter (3), and Pseudornonas (2).

J . G . S .

Safety of the hepatitis B vaccine

Stevens CE, Taylor PE, Rubinstein P, et al: N Engl J Med 312:375-376, 1985

Sera from 212 participants in an efficacy study of hepatitis B vaccine were evaluated for HTLV-III antibody. Seroeon- version rates in men who were antibody-negative on entry were identical in the vaccine placebo groups (33.7% vs 32.7%). There was no evidence from the study that hepatitis

B vaccine induced an antibody response to HTLV-III, pro- tected against HTLV-III infection, or contained transmissible HTLV-III.

J .G .S .

Aspartame-induced granulomatous panniculitis

Novick NL: Ann Intern Med 102:206-207, 1985

Within 2 weeks after beginning ingestion of 1 to 1.3 liters of aspartame-sweetened diet soda per day, a 22-year-old woman noted nontender nodular lesions 0.5 to 5 cm in di- ameter on both thighs and legs. The overlying skin was nor- mal, the nodules were firm, and in some areas they coalesced to form large, deep plaques. Histologically, a septal pannic- u/iris with multinucleated giant cells and lymphohistiocytic infiltrate extending into adjacent fatty lobules were found. It cleared when she stopped drinking aspartame-sweetened bev- erages, flared on challenge with aspartame-sweetened diet drink, and flared again when challenged with pure aspartame, 50 mg four times daily.

J . G . S .