The impact of predatory bacteria on experimental periodontitis

BACKGROUND: This study evaluated the effects of topical administration of Bdellovibrio bacteriovorus HD100 on experimental periodontitis (EP) in rats. METHODS: Thirty-two rats were divided into groups C (control), EP, C-HD100, and EP-HD100. At day 0, animals of groups EP and EP-HD100 received cotton ligatures around mandibular first molars (MFM). In groups C-HD100 and EP-HD100, 1 mL of suspensions containing B. bacteriovorus HD100 was topically administered in the subgingival region of MFMs at days 0, 3, and 7. Animals were euthanized at day 14. Gingival tissue, hemimandibles, and oral biofilm were collected. Data were statistically analyzed. RESULTS: Group EP-HD100 presented greater bone volume and lower connective tissue attachment loss (CTAL) than group EP (P < 0.05). Group EP-HD100 presented greater proportions of Actinomyces and Streptococcus-like species and lower proportions of Prevotella intermedia, Peptostreptococcus micros, Fusobacterium nucleatum, Fusobacterium polymorphum, Eikenella corrodens, Eubacterium nodatum, Campylobacter gracilis, Capnocytophaga sputigena, and Veillonella parvula-like species than group EP. Group EP-HD100 presented greater levels of osteoprotegerin and gene expression of interleukin (IL)-17, IL-10, and forkhead box P3 than group EP (P < 0.05). CONCLUSION: Topical use of B. bacteriovorus HD100 promotes a protective effect against alveolar bone loss and CTAL in rats with EP.