Odontogenic Infections Resistant to Empiric Therapy, Opportunistic Prevotella, and Metronidazole: A Clinical Case Series and Review of the Literature

Background/Objectives: Treating odontogenic infections of the head, neck, and oral cavity requires surgical and pharmacotherapeutic interventions of single and multi-space infections. Prevotella species can become virulent during post-extraction wound healing at an extraction site, under conditions of excessive plaque, nearby gingivitis, or periodontitis, and in immunocompromised patients. The aims of this narrative review are to describe the pathogenesis of Prevotella species, particularly those resistant to surgery and empiric antibiotic therapy, and to emphasize the need for the identification of specific antibiotic-resistant Prevotella species. Methods: Three clinical cases from the lead author’s private practice were described, in which Prevotella species were significant opportunistic pathogens in odontogenic infections. The PubMed database was searched for “Prevotella and Odontogenic Infection and (or Amoxicillin or Clindamycin or Metronidazole or Flagyl®)” from 1996 to 2024. Thirty additional references were used to develop the section on Prevotella pathogenesis. Results: Metronidazole administration was deemed necessary in the cases described here. This intervention mitigated or resolved these odontogenic infections that were refractory to conservative surgical therapy that included source control. Prevotella buccae was found to be prevalent in odontogenic infections and pericoronitis, and to be resistant to commonly used antibiotics. Prevotella species were highly susceptible to Metronidazole (Flagyl®). The antibiotic was effective in mitigating the disease when basic principles of the treatment of odontogenic infections were employed. Conclusions: The clinical cases and the review of the literature indicate that Metronidazole is strongly indicated for the treatment of odontogenic opportunistic infections with Prevotella species.