# Host modulation therapy in periodontitis: from established therapies to emerging technologies

## TL;DR

Periodontitis is a chronic gum disease caused by bacteria and immune response, and new therapies aim to target both bacteria and inflammation to improve treatment.

## Contribution

This review highlights current host modulation therapies for periodontitis and identifies their limitations to guide future improvements.

## Key findings

- Periodontitis is driven by microbial dysbiosis and excessive host inflammation.
- Current host modulation therapies have limitations including adverse effects and disease rebound.
- Emerging strategies aim to target both oral microbiota and immune response for better outcomes.

## Abstract

Periodontitis is a biofilm-induced chronic inflammatory disease, characterized by gingival inflammation and alveolar bone loss. According to a national survey, approximately half of the U.S. adults are affected by periodontal disease. To effectively prevent and treat periodontitis, it is essential to address its underlying causes. The primary etiological factors include polymicrobial synergy and dysbiosis of the oral microbiota, and a dysregulated immune response. The standard therapeutic approach, mechanical removal of biofilm through debridement, sometimes demonstrates limited efficacy, particularly in cases of severe periodontitis, which may require adjunctive or additional therapy. Emerging evidence indicates that periodontal tissue destruction is initiated by biofilm but primarily driven by a sustained, dysregulated host inflammatory response characterized by excessive cytokine production, osteoclast activation, and impaired inflammation resolution. In recent years, research has focused on targeting both the oral microbiota and immune response by utilizing antimicrobial therapeutics to diminish bacterial load and by modulating immune activity. Specifically, host modulation therapies (HMTs), such as the delivery of anti-inflammatory cytokines, nonsteroidal anti-inflammatory drugs (NSAIDs), low-dose doxycycline, and lipid mediators, via various techniques, have been explored. However, challenges associated with its use encompass adverse effects resulting from prolonged administration, and systemic delivery methods are associated with an elevated risk of infection and the potential development of malignancy, as well as the disease rebound after cessation of treatment. This review examines current trends in HMTs for periodontitis and identifies potential limitations of these approaches. The insights gained may contribute to the development of improved strategies to enhance periodontal treatment outcomes.