Effectiveness of dental floss in the management of gingival health: A 6-month follow-up of a randomized controlled clinical trial

Objectives To evaluate, (i) if subjects submitted to a structured oral hygiene training program (OHt) maintain adopted habits over 180 days without professional guidance; and (ii) in perspective whether flossing provides additional benefits to toothbrushing on gingival health. Materials and methods Seventy-five adult subjects showing approximately 40% proximal gingival bleeding were randomized to receive OHt (1 session weekly over 8 weeks) using toothbrush and dental floss or toothbrush alone. The subjects were then followed over 180 days without professional guidance. Primary outcomes were mean interproximal Gingival Index (GI) and GI = 2 (gingival bleeding). Mixed linear models were used for the comparison between groups (p < 0.05). Results68 subjects received OHt, 48 subjects completed the 180-day follow-up. Subjects maintained adequate oral hygiene routines. Besides a reduction in gingival inflammation, no alterations in gingival status were observed among groups, subjects additionally instructed to use dental floss showing a mean interproximal GI = 2 of 12.8 +/- 2.5 compared with 19.8 +/- 2.2 for subjects limited to tooth brushing alone. Conclusions OHt intensive training promotes gingival health and maintenance lasting at least 6 months without professional supervision reinforcing important principles: (i) dental health professionals should dedicate time training and motivating their patients to reach adequate self-performed plaque control; and (ii) the adjunctive use of dental floss appears essential to reduce interproximal gingival inflammation in subjects with intact interdental papillae. Clinical relevance Dentists need to invest time in training/motivating/engage their patients to achieve adequate OH; adjunct flossing in subjects with papilla filling the interdental space appears essential to reach and maintain gingival health. Clinicaltrials.Gov(53831716.5.0000.5346). Trial registration The protocol registration was filed May 9, 2018 (# 538,311,716.5.0000.5346) on ClinicalTrials.gov. An NCT number (NCT04909840) was generated upon completed registration.