Efficacy of dental floss in the management of gingival health: a randomized controlled clinical trial

Objectives This randomized controlled clinical trial evaluated the efficacy of dental floss as a supplement to toothbrushing in support of gingival health in adults. Materials and methods Seventy-five systemically healthy subjects, non-smokers, without loss of interproximal periodontal attachment and with more than 15% of the interproximal sites presenting with gingival bleeding were randomized into two groups either performing toothbrushing supplemented by dental floss (TB + DF) or toothbrushing (TB) alone. Over a 60-day period, participating subjects weekly received oral hygiene instruction and supervised personal and professional plaque removal by applying the devices assigned for the group. Study subjects were instructed to perform toothbrushing twice daily (group TB + DF and TB) and use dental floss once daily (group TB + DF). Gingival Index (GI) and Plaque Index (PlI) were evaluated at baseline, and at 30 and 60 days. Linear mixed models were used to compare PlI and GI intra- and intergroup means. Results Interproximal gingival inflammation (GI = 2 and mean GI) was significantly reduced in both groups by day 30, reduction in inflammation being significantly greater in the TB + DF compared with the TB alone group. No further significant alterations were observed by day 60. Moreover, reduction in gingival inflammation (GI = 2) was greater in the anterior compared with the posterior dentition. Conclusions Interproximal gingival inflammation may be significantly reduced by toothbrushing alone, the effect being significantly enhanced when toothbrushing is combined with dental floss. Trial registration The protocol registration was filed on May 9, 2018 (# 538,311,716.5.0000.5346) on ClinicalTrials.gov and after complete registration, a NCT number was generated (NCT04909840). Since the date in May 2018 when the protocol preregistration was filed, no change in methodology, primary outcome, and data analysis has occurred. Clinical relevance Optimized personal oral hygiene routines in individuals without loss clinical attachment interproximal should include dental floss as a supplement to toothbrushing in support of gingival health.