Introduction: Topical hyaluronic acid (HA) has been considered as an adjuvant agent for periodontitis (PD). Objectives: This study aimed to assess the clinical effects of subgingival application of 0.2% HA gel, following scaling and root planning (SRP) in PD patients. Material and methods: In this randomized split-mouth study, 733 periodontal pockets of 28 patients with PD were investigated. They were divided into control and experimental groups. The experimental group received subgingival administration of 1 ml 0.2% HA gel into each pocket immediately after SRP, and then after 1 week, 2 weeks, and 3 weeks. Clinical parameters and subgingival plaque were assessed at baseline and 6 weeks after SRP. Quantitative real-time polymerase chain reaction for Porphyromonas gingivalis (Pg), Treponema denticola (Td), Fusobacterium nucleatum (Fn), and Tannerella forsythia (Tf) were also performed. Results: After 6 weeks, there were significant decreases in clinical parameters, and the number of Fn in the experimental group compared to the control group (p < 0.05). The number of Pg, Td, and Tf decreased significantly in both groups, with no significant difference between the 2 cohorts (p > 0.05). Conclusions:The topical application of HA gel in periodontal pockets after SRP may have a beneficial effect in PD patients. This additional treatment appears to help reducing 2 types of bacteria (Tf and Fn) better than non-surgical treatment only. Trial registration: Identifier NCT04675385 in ClinicalTrials.gov.

Mini-abstract In this retrospective study, we evaluated changes in measures of surgeon clinical combat readiness within the military health system during the COVID-19 pandemic. We found a 36% reduction in surgical knowledge and skills as compared to pre-COVID. Sizable reductions were encountered for surgery for colectomy (−50%) and aneurysm repair (−61%).