Tooth brushing and flossing are usually both hallmarks of a good oral hygiene routine to prevent decay, gingivitis, and periodontitis. While brushing removes much of the oral bacteria from the front and backs of the teeth, flossing is believed to be necessary to remove bacteria between the teeth. However, the effectiveness of self-flossing has not been established very well. Flossing effectiveness was evaluated two ways in this study: adults and 12 year old children were instructed on how to floss and bacterial colonies were determined before or after 7 days or pediatric and family dentists were blinded to patient surveys that asked about flossing frequency and evaluated the patient for gingivitis. We found a significant number of children did not floss at all despite brushing daily. However, flossing had no effect on the number of bacteria in their mouths nor did flossing have any correlation with reducing gingivitis development. Taken together, self-flossing did not appear to be an effective strategy for reduction of gingivitis in children or adults but could stem from improper technique or simply a lack of doing it.

The authors have declared no competing interest.

This study did not receive any funding

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ames Iowa Unified School IRB. All patients were enrolled with an informed consent intake form signed by themselves for adults or by their parent/ a minor and their guardians if a minor.

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Yes

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Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

All data produced in the present study are available upon reasonable request to the authors