Laird Harrison

April 17, 2012

April 17, 2012 (Tampa, Florida) — Subjects who used a 0.1% cetylpyridinium chloride (CPC) mouth rinse (Crest Pro-Health Clinical, Proctor & Gamble) accumulated significantly less plaque than those who used routine dental hygiene, researchers announced here at the American Association for Dental Research 2012 Annual Meeting.

Subjects who brushed and used the rinse for 2 months had less than half the overnight accumulation of plaque than subjects who only brushed, researchers reported.

"At all time points, the CPC group showed a significant reduction in mean plaque area coverage, while the control group increased significantly from the baseline," said Mabi Singh, DMD, MS, associate professor of public health research and oral medicine at Tufts University in Boston, Massachusetts.

The maker of Crest Pro-Health Clinical, Procter & Gamble, sponsored the trial.

The researchers randomly assigned 34 subjects (mean age, 42.3 years) to either the rinse or the control group. The rinse group rinsed with 20 mL of the 0.1% CPC rinse for 30 seconds twice a day after brushing, and refrained from flossing. The control group only brushed twice a day. The subjects followed their treatments at home without supervision.

The age, race, and sex of the participants were not statistically different in the 2 groups. Of the 34 participants, 15 in the rinse group and 14 in the control group (n = 29) completed the 2-month study.

The researchers used a novel digital imaging technique to measure plaque reduction. Subjects rinsed for 10 seconds with 25 mL of phosphate buffer, then rinsed for 1 minute with 5 mL of 1230 ppm sodium fluorescein in phosphate buffer as a disclosing dye. They then rinsed again for 10 seconds with 25 mL of phosphate buffer.

After this process, subjects sat on a stool with their chins on a rest and their lips and cheeks retracted with nonreflective plastic retractors. Their anterior teeth were centered facing a high-resolution digital camera with a fixed focal length and an ultraviolet flash.

Pixels in the image were classified as either tooth or plaque, and a computer calculated the percentage of the tooth surface covered by plaque.

At baseline, all subjects had a mean overnight plaque area of 24.3%.

After 1 day, subjects in the control group significantly reduced their mean plaque area to 8.8% (P < .05). After 2 weeks, the plaque area increased to 19.4%, and after 2 months it was 18.8%.

In contrast, the rinse group reduced its plaque area to 5.5% at day 1. After 2 weeks, the plaque area increased to 6.2%, and after 2 months it was 9.1%.

Treatments differed significantly (P < .003) between the 2 groups, beginning at day 1 and continuing throughout the trial.

The researchers noted 4 possible, 1 probable, and 1 doubtful adverse events in the rinse group, including taste loss, pain, and discolored tongue. They recorded 2 doubtful and 1 "not related" adverse events in the control group.

The subjects in the control group probably reduced their plaque on the first day because being in the trial made them pay more attention to brushing, researcher Athena Papas, PhD, DMD, director of the Tufts Oral Medicine Department, told Medscape Medical News.

"What's interesting is that 1 day after you get clean, the plaque starts to form again," she said. "With CPC, it didn't come back after even 2 months."

Asked to comment, session moderator Elliot Hersh, DMD, MS, PhD, told Medscape Medical News that the study was well designed but preliminary. "The data suggest that the drug is active," he said.

Other Procter & Gamble–sponsored studies presented showed that the 0.1% CPC rinse is more effective than Listerine Cool Mint (Johnson & Johnson) for breath malodor and plaque.

Dr. Singh, Dr. Hersh, and Dr. Papas have disclosed no relevant financial relationships.

American Association for Dental Research (AADR) 2012 Annual Meeting: Abstract 119. Presented March 22, 2012.


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