Panasonic Joint Study Shows Water Flosser Use with Toothbrush Reduces Plaque by Approx. 40% for Orthodontic Patients

Panasonic Corporation, in collaboration with Professor Shinichi Negishi of the Department of Orthodontics at Nihon University School of Dentistry at Matsudo, has demonstrated that for oral care during orthodontic treatment, the combined use of a toothbrush and a jet washer effectively reduces plaque adhesion and leads to better oral hygiene.

In recent years, interest in orthodontics has grown due to increased awareness of dental alignment and aesthetics. However, many who undergo treatment face the challenge of difficult tooth brushing. Orthodontic appliances complicate the oral environment, making it easier for plaque to accumulate. This is particularly true for conventional wire braces, where food particles can easily get trapped in the complex apparatus, increasing the risk of inadequate cleaning.

Addressing this issue, Panasonic commissioned a study with Professor Negishi to compare plaque adhesion rates in patients with wire braces, comparing a group using only a toothbrush to a group using both a toothbrush and a jet washer (model EW-DJ55).

**[Verification Results]** After one month, the group that supplemented their regular brushing with a jet washer showed an approximate 40% reduction in plaque adhesion compared to the toothbrush-only group (p<0.01). This indicates that the adjunctive use of a jet washer contributes to maintaining a healthier and cleaner oral environment.

The study methodology was as follows: - Location: Department of Orthodontics, Nihon University School of Dentistry at Matsudo. - Devices: Standard toothbrush and Panasonic Jet Washer EW-DJ55 (used at water pressure level 5 with ultrasonic water flow nozzle). - Evaluation: Assessed using the Plaque Control Record (PCR) after one month of use. - Subjects: Patients with multi-bracket wire braces on upper and lower jaws (Toothbrush group n=7, Jet Washer group n=11).

**[Comment from Professor Shinichi Negishi]** While wire braces are an effective treatment, they present a challenge by making cleaning difficult, which can increase the risk of cavities and other issues. Thorough daily brushing by patients is crucial, but a toothbrush alone has its limits. Auxiliary tools like dental floss exist, but their complex operation can discourage consistent use. In this context, a jet washer, which easily cleans away debris with a high-pressure water stream, is a valuable option for orthodontic patients to maintain oral hygiene.

Panasonic's Jet Washer Doltz utilizes patented 'ultrasonic water flow' technology to gently and effectively clean periodontal pockets, interdental spaces, and the areas around orthodontic appliances. The models with this technology, first launched in 2017, are projected to reach a cumulative domestic shipment of one million units by November 2024, indicating wide consumer adoption.

Panasonic intends to continue proposing its jet washer, developed from years of technology and research, as a product for high-quality self-care that complements professional dental care.