Adjunctive Treatment Effect of Non-Thermal Atmospheric Pressure Plasma in Periodontitis-Induced Rats.

Background/

Objectives

As non-thermal atmospheric pressure plasma (NTP) is known to have advantages in application in the medical field, we consider its applicability to periodontitis, a representative chronic inflammatory disease. The purpose of this study was to evaluate the effect of NTP in inhibiting the progression of periodontitis in a rat model when additionally used in scaling and root planing (SRP).

Methods

To induce experimental periodontitis in 20 rats, ligatures were placed in the maxillary second molar and lipopolysaccharide from Porphyromonas gingivalis was injected around the teeth. Then, NTP treatment was performed for 2 or 5 min, together with scaling and root planing (SRP). To evaluate alveolar bone loss, micro-computed tomography (micro-CT) analysis and hematoxylin-eosin (H-E) staining were performed. Tartrate-resistant acid phosphatase (TRAP) analysis was performed to compare the number of osteoclasts, while immunohistochemistry (IHC) analysis was performed to determine the expression levels of receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG). Enzyme-linked immunosorbent assay (ELISA) analysis was performed for the detection of cytokines (TNF-α, IL-1β, and IL-10) in tissues and sera.

Results

When SRP was combined with NTP, alveolar bone loss was decreased, the number of osteoclasts and RANKL expression were decreased, OPG expression was increased, and pro-inflammatory cytokine (TNF-α and IL-1β) levels were significantly decreased. Compared with the NTP treatment for 2 min, when treated for 5 min, less alveolar bone loss, fewer osteoclasts, a lower RANKL expression level, and a higher OPG expression level were observed.

Conclusions

This study evaluated the adjunctive treatment effect of NTP in periodontitis-induced rats. Based on the results of this study, we suggest that supplemental NTP treatment may be a good option for non-surgical periodontal treatment; however, further studies are needed to elucidate the mechanism through which NTP suppresses periodontal inflammation.