Humorist S.J. Perelman once wrote of his joy at going to the dentist, "Every 12 years, I would drop whatever I was doing and allow wild Caucasian ponies to drag me to a reputable orthodontist." Millions of Americans feel the same way, and one of the reasons is periodontitis, a gum infection as common as it is nasty. The symptoms are bleeding, swelling and bad breath; it's the leading cause of tooth loss in adults; 75 percent of Americans over 35 have it; and they spend $350 million a year trying to get rid of it. Until recently the only way to do that was a masochist's delight, oral surgery.

Then about four years ago Dr. Paul Keyes, a former staffer at the National Institute of Dental Research (NIDR), began touting an alternative two-part treatment that is simpler, cheaper, less painful—and very controversial. Part one requires detecting the disease via microscopic analysis. Part two—popularly known as the "salt-and-soda" regimen—involves a special cleaning by a dentist of the teeth and gums, sometimes brief antibiotic therapy, and, at home, massaging the gums and brushing the teeth daily with a paste made from baking soda and an antibacterial agent such as hydrogen peroxide. The last step, Keyes says, can also serve as an effective periodontitis preventative. "Brush with soda every day and you'll never lose teeth," says Keyes.

Perhaps not surprisingly, his claims have led to professional inflammation. Skeptics have called the treatment "the Laetrile of dentistry," and an American Academy of Periodontology position paper states flatly: "When periodontal disease is advanced, surgical treatment has been shown to be more effective than nonsurgical treatment in at least three independent long-term studies. There are no such studies thus far showing that treatment advocated by Dr. Keyes is an effective alternative."

Keyes has noted that, at 66, he doesn't have time to do long-term research. He bases his faith on his own clinical research and two short-term studies. In the first, conducted by him in 1973, 90 patients with serious periodontitis showed radical improvement in a few months, he claims. The second, conducted in 1981 by Congress' Office of Technology Assessment, found gum bleeding reduced by two-thirds and the number of loose teeth by 80 percent in 190 patients tested. Says Dr. Paul Cummings Jr., a Wilmington, N.C. periodontist who three years ago converted to the Keyes approach, "In 25 years of practice, I've never had better results. I can get even the most difficult case under control now for about $800. The same case would have cost $2,500 to $4,000 if it were treated surgically."

Some of Keyes' supporters claim that his detractors have a vested interest in expensive dental surgery. The detractors argue that Keyes, who in 1981 set up a foundation to promote his theory, also stands to profit handsomely. Keyes denies it.

Whatever the merits of his cure, Keyes has made solid contributions in the past. The son of a Long Island magazine publisher, he attended the University of Pennsylvania dental school and began practicing in New York, but soon quit because, he says, "It was depressing. Despite my best efforts, people's dental health deteriorated before my eyes." He turned to research and teaching, and spent eight years on the Harvard faculty before joining the National Institutes of Health, parent of the NIDR, in 1955, where he became nationally known for landmark work on cavities. There he came across a 50-year-old paper by a University of Minnesota dentist claiming that periodontitis could be countered by antibacterial agents.

Keyes, who retired from NIDR in 1981, lives in Bethesda, Md. with his wife, Doris, 60, and spends most of his time shuttling around the country. "The only reason the health field has been able to get away with not finding a cure for periodontitis is because we can get along without teeth," says Keyes. "If a more vital structure were affected, like a hand or an internal organ, we would have had it figured out long ago."