Clinical examination and treatment
Emdogain® FL, bleeding, Orthodontic floss, Superfloss®
STERILE, BLEEDING, EMD
Periodontal treatment consisted of whole-mouth supragingival debridement applying sonic debridement (Sonicflex® T KaVo, Biberach, Germany) as well as erythritol powder air polishing (AIRFLOW® Prophylaxis Master, E.M.S. Electro Medical Systems S.A, Nyon, Switzerland). Subgingival instrumentation of sites with PPD ≥ 6 mm was conducted with Gracey curettes (At the completion of subgingival instrumentation for participants in test group (EMD +), a 24% EDTA solution (Prefgel®; Institute Straumann AG, Basel, Switzerland) was inserted into the gingival sulcus using prefilled sterile syringes. The sites were then rinsed with saline solution. After irrigation, sterile gauze was used to prevent saliva contamination of the selected sites, followed by gentle air-drying. Orthodontic floss (Superfloss®; Oral B, Ireland) was placed and left in the site for 1 min. Irrigation and floss application were repeated until complete bleeding control. Afterwards, EMD (Emdogain® FL; Institute Straumann AG, Basel, Switzerland) was applied on each site, until overflow of the gel from the marginal gingiva was achieved. In control group patients (EMD-), saline solution was applied after subgingival instrumentation. Clinical procedures were performed without local anesthesia.All patients were instructed to apply chlorhexidine gel (Chlorhexamed 1% Gel, GlaxoSmithKline, Brentfort, UK) at the treated sites for 2 weeks and to refrain from brushing and flossing at the respective areas. At weeks 3 and 4, patients were told to use a soft toothbrush for the treatment sites. Afterwards, oral hygiene was performed as usual. Treatment procedures were performed by two certified examiners with a specialization in periodontology (CW, GD). Re-assessment was performed 6 months post-treatment by a third examiner who was blinded to the treatment method (DT).All three examiners involved in study procedures were calibrated for inter-examiner reliability assessing PPD in 42 randomly chosen sites. Measurements were performed with a calibrated standard probe. Intraclass correlation coefficient (ICC) was 0.979 (95% CI 0.965–0.988; 