Th17 cells and IL-17 receptor signaling are essential for mucosal host defense against oral candidiasis

The commensal fungus Candida albicans causes oropharyngeal candidiasis (OPC; thrush) in settings of immunodeficiency. Although disseminated, vaginal, and oral candidiasis are all caused by C. albicans species, host defense against C. albicans varies by anatomical location. T helper 1 (Th1) cells have long been implicated in defense against candidiasis, whereas the role of Th17 cells remains controversial. IL-17 mediates inflammatory pathology in a gastric model of mucosal candidiasis, but is host protective in disseminated disease. Here, we directly compared Th1 and Th17 function in a model of OPC. Th17-deficient (IL-23p19−/−) and IL-17R–deficient (IL-17RA−/−) mice experienced severe OPC, whereas Th1-deficient (IL-12p35−/−) mice showed low fungal burdens and no overt disease. Neutrophil recruitment was impaired in IL-23p19−/− and IL-17RA−/−, but not IL-12−/−, mice, and TCR-αβ cells were more important than TCR-γδ cells. Surprisingly, mice deficient in the Th17 cytokine IL-22 were only mildly susceptible to OPC, indicating that IL-17 rather than IL-22 is vital in defense against oral candidiasis. Gene profiling of oral mucosal tissue showed strong induction of Th17 signature genes, including CXC chemokines and β defensin-3. Saliva from Th17-deficient, but not Th1-deficient, mice exhibited reduced candidacidal activity. Thus, the Th17 lineage, acting largely through IL-17, confers the dominant response to oral candidiasis through neutrophils and antimicrobial factors

Antibiotic Prescribing Practices in Periodontal Surgeries with and without Bone Grafting

Background: The prevention of post-operative infection following periodontal surgery is often the basis for antibiotic prescription. The inherent risks of unwarranted antibiotic use and lack of guidelines for procedures involving bone grafts create additional difficulties in decision making for practitioners. This study aims to evaluate practitioners' self-reported practices in antibiotic prescribing for periodontal surgeries with and without bone grafting.Methods: A 15-question anonymous survey using Qualtrics software was distributed to California periodontists via email. The survey included questions about prescribing practices for specific periodontal procedures, rationale questions for choosing to prescribe or not to prescribe antibiotics, demographic and dental practice information. Results were analyzed using McNemar tests and logistic regression.Results: 100 practitioners responded to the survey. Practitioners were significantly less likely to report prescribing antibiotics for traditional periodontal surgeries involving no bone grafting compared to socket preservation, guided tissue regeneration (GTR), guided bone regeneration (GBR) and sinus augmentation (p<0.0001). Practitioners were significantly more likely to report prescribing antibiotics with more complex procedures involving bone grafting, such as GBR and sinus augmentation, when compared to socket preservation (p<0.0001). Seventy-five percent of practitioners responded that they would follow guidelines for antibiotic prescription with boneivgrafting procedures if they were developed and endorsed by the American Academy of Periodontology.Conclusions: Practitioners are more likely to prescribe antibiotics when a bone graft is used and as the complexity of the bone-graft procedure increases. Based on these results and the willingness of practitioners to adopt evidence-based guidelines, the establishment of guidelines for practitioners on the appropriate use of antibiotics would be of benefit to the periodontal practicing community