Last August, the Associated Press reported that the evidence supporting flossing’s effectiveness wasn’t reliable. Yet new research from Julie Marchesan, PhD, of the University of North Carolina, Chapel Hill, has associated flossing with a lower risk of tooth loss over periods of 5 and 10 years, using data from the National Health and Nutrition Examination Survey (NHANES) 2009-14, the Dental Atherosclerosis Risk in Communities (DARIC) study, and Piedmont 65+ Dental Study (PDS).
Standardized examiners in these studies used the extent of interproximal clinical attachment levels (iCAL) equal to or greater than 3 mm and interproximal probing depth (iPD) equal to or greater than 4 mm. Tooth loss data was available via a 10-year follow-up questionnaire in DARIC, and 5-year tooth loss was calculated based on the PDS exam. Demographic data as well as brushing and flossing frequencies were collected via questionnaire. All analysis adjusted for age, race, gender, diabetes, tobacco use, and education.
DARIC flossers had a lower mean extent of sites with iCAL of 3 mm or greater compared to nonflossers, or 22% versus 26.7%, respectively. The NHANES findings were similar, with 20% versus 29.5%. Overall, the DARIC subjects who flossed at least once a week and brushed up to twice a day showed lower levels of clinical measurements than nonflossers.
Plus, the DARIC data showed that nonflossers had a 1.25 excess risk for losing at least 3 teeth in 10 years. Similar data in the PDS showed a 3.23 excess risk of losing at least 3 teeth in 5 years. Based on these results, Marchesan associated flossing with a lesser extent of iCAL and iPD even among subjects who brushed once or twice a day. She also associated flossing with a lower risk of tooth loss within 5 and 10 years.
The study, “Flossing Is Associated with Disease Prevalence and 10-Year Tooth Loss,” was presented at the 95th General Session & Exhibition of the International Association for Dental Research in March in San Francisco.