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In the new study, published in the Journal of Periodontology, researchers at Tufts University in Boston looked at the longer-term results of an alternative procedure known as guided tissue regeneration, or GTR.

The study looked at a specific GTR technique, developed at Tufts, that involves drawing blood from the patient to retrieve blood cells known as platelets, which are rich in proteins called growth factors that aid in tissue repair and wound healing.

A membrane made of collagen is soaked in the platelets then sutured over the receding tooth root.

Drs. Terrance J. Griffin and Wai S. Cheung followed six patients who had had the procedure done on a total of 37 teeth. After six months, new tissue was completely covering the roots of two-thirds of the treated teeth. After three years, 57 percent still had complete root coverage.

The long-term results are comparable to what is seen with traditional graft surgery, Griffin told Reuters Health.

"The new treatment reduces pain and discomfort, offers excellent root coverage, and results in increased patient satisfaction with the results," he said. "We now know that it is stable after three years."

The treatment is not yet widely available, according to Griffin, though it is becoming better known.