Rotational oscillation action more effective according to independent study

Jan. 14, 2003
The reviewers analyzed studies of five types of powered toothbrushes in addition to those with rotational oscillation action.

Powered toothbrushes with rotational oscillation action are more effective in removing plaque and reducing gingivitis than are manual toothbrushes or other types of powered brushes, an independent, international research team reported recently.

The finding was announced by The Cochrane Collaboration, an independent, international, nonprofit organization, at a conference sponsored by the Forsyth Center for Evidence-Based Dentistry (EBD) in Boston.

"Rotational oscillation toothbrushes removed up to 11 percent more plaque and reduced gingival bleeding by up to 17 percent more than did manual or other power toothbrushes," said William Shaw, PhD, MScD, joint co-coordinating editor of the Cochrane Oral Health Group, which analyzed data from clinical trials conducted over 37 years. The Cochrane Oral Health Group is one of 50 review groups of The Cochrane Collaboration, which provides and disseminates systematic reviews of health research findings.

Richard Niederman, DMD, Director of the Forsyth Center for Evidence-Based Dentistry called the study: "one of the most comprehensive independent reviews of powered toothbrushes ever conducted." The EBD Center, originally established at the Harvard School of Dental Medicine, moved to The Forsyth Institute in 2001. Forsyth is an independent, nonprofit research institute focused on oral, craniofacial and related biomedical science.

In the Cochrane study, six reviewers independently extracted data from reports on twenty-nine clinical trials involving a total of 2547 participants in North America, Europe and Israel. The clinical trials, conducted between 1964 and 2001, compared the effectiveness of all forms of manual and six types of power toothbrushes with mechanically moving heads when used short-term (one month) and long-term (up to three months).

The reviewers analyzed studies of five types of powered toothbrushes in addition to those with rotational oscillation action. The five others included brushes with side-to-side action, counter-oscillational action, circular action, sonic and ultrasonic action, and unknown action. The short-term comparison between sonic and manual brushes reached borderline statistical significance for plaque removal, but data on long-term results were limited because only one trial was available for analysis.

Only the rotational oscillation toothbrushes proved more effective than manual toothbrushes in reducing plaque and gingivitis.

Shaw emphasized that the review results do not indicate that toothbrushing is only worthwhile with a powered toothbrush. "There is overwhelming evidence that toothbrushing reduces gingivitis," he said. "Brushing may prevent periodontitis, and brushing certainly prevents tooth decay if used with fluoride toothpaste. These benefits occur whether the brush is manual or powered."

Powered toothbrushes included in the study were: Braun Oral B Plaque Remover (rotational oscillation); Philips Sonicare (sonic side-to-side action); Interplak (counter oscillation); Teledyne Aqua Tech (circular action); Ultrasonex brush (ultrasonic side-to-side action); and Rowenta Dentiphant, Rowenta, and Plaque Dentacontrol Plus (unknown actions).

Toothbrushes subjected to trials briefer than one month and those brought to market after 2001 were not included in the review.

Because the trials examined were of limited duration and did not test brushes for durability, the research did not lead to recommendations for any particular toothbrush type or brand.

Powered brushes were first introduced commercially in the early 1960s and have become an established alternative to manual methods of toothbrushing. In the United States, the volume of power toothbrush sales tripled from approximately three percent of all toothbrush sales in 1999 to more than nine percent in 2001, according to the Journal of Contemporary Dental Practice. In the United Kingdom, the volume of sales of powered toothbrushes nearly doubled each year between 1999 and 2001, increasing from two percent of total sales of all toothbrushes in 1999 to seven percent in 2001, the report states.

The review is to be published in the January edition of The Cochrane Library, a regularly updated collection of high quality information on health care.