Repeated local delivery of hyaluronic acid gel as adjunctive treatment of residual pockets in periodontitis patients undergoing supportive periodontal care. A randomized controlled clinical trial.

"Declarations Ethics approval and consent to participateThe study protocol was approved by the regional ethical review board (Dnr. 2016/468) and all patients were included after providing a signed informed consent. Competing interestsThe authors declare no competing interests. Competing interests The authors declare no competing interests."

"Funding Open access funding provided by Malmö University. The present study was supported by TePe Munhygienprodukter AB (national research grant; Malmö, Sweden) and Sunstar Europe SA (Etoy, Switzerland). Furthermore, Interdental brushes and the hyaluronic acid containing gel (GUM®AftaClear Gel) were provided free of charge from TePe Munhygienprodukter AB and Sunstar Europe SA, respectively."

"The present study was a randomized, double-blinded (patient and observer), placebo-controlled, parallel-group clinical trial with 12 months follow-up and is reported in accordance with the standards of reporting clinical trials (CONSORT Statement; Appendix ) []. The protocol was approved by the regional ethical review board (Dnr. 2016/468) and registered at clinicaltrials.gov (NCT04792541); any changes in the protocol after its publication are listed in Appendix . Patient recruitment was performed between December 2016 and January 2020, i.e., patient recruitment started prior to the World Workshop on the Classification of Periodontal and Peri‐Implant Diseases and Conditions in 2017 [, ]. All periodontitis patients, that had completed the active treatment phase since ≥ 6 months and were enrolled in a regular SPC program (i.e., step 4 of treatment) in a Specialist Clinic for Periodontology (Public Dental Service, Värmland, Sweden), fulfilling the following inclusion criteria were consecutively included: (i) 35 to 75 years old, (ii) diagnosis of chronic periodontitis [], (iii) at least 10 remaining teeth, and (iv) 4 to 8 interproximal sites with PPD of ≥ 5 to < 8 mm and presence of BoP at timepoint of inclusion. Further, the following exclusion criteria were defined: (i) molars with furcation involvement class II or III [], (ii) class II or III tooth mobility, (iii) > 2 mm deeper PPD at another site in the same interproximal space (iv) antibiotic therapy in the preceding 6 months or during study participation, (v) need for antibiotic prophylaxis prior to periodontal examination and/or treatment, (vi) long-term use of anti-inflammatory and immunosuppressive medication, (vii) uncontrolled or newly diagnosed diabetes prior to or during study participation, (viii) pregnancy or lactation, (ix) severe occlusal dysfunction, (x) ongoing orthodontic treatment, and (xi) endodontic lesions. Age, gender, smoking status (i.e., never / former / current smoker) and presence/absence of a well-controlled diabetes mellitus was recorded for each participant."