Objective The purpose of this study is to investigate the pathogenic role of PPARα in periodontal antigen treated gingival cells in vitro and in experimental periodontitis in vivo . Methodology Gingival fibroblasts, gingival epithelial cells and splenocytes were isolated from C57BL/6J wild type (WT) mice and treated with fixed P. gingivalis at for 48 hours. The mRNA levels of PPARs, TNFα, IL-1β and IL-10 were detected by Real-time quantitative PCR. Silk ligatures after being soaked in the P.gingivalis suspension were tied around both maxillary second molars of WT mice or PPARα knock-out (KO) mice for two weeks. PPARα agonist fenofibrate and vehicle control were injected into the different side of the palatal gingiva on days 3, 6, and 9. At day 14, bone resorption and gingival mRNA expression levels of PPARs, TNFα, IL-1β and IL-10 were measured by micro-computed tomography and RT-qPCR respectively. Results P. gingivalis treatment downregulated the expression of PPARα, but not PPARβ or PPARγ, and increased the expression of TNF-α and IL-1β in Gingival fibroblasts, gingival epithelial cells and splenocytes from WT mice. Gingival mRNA levels of PPARα were significantly decreased in experimental periodontitis in WT mice. The bone loss of PPARα KO mice in experimental periodontitis was significantly higher than WT mice and was not reduced by fenofibrate treatment. Gingival TNFα protein expressions were significantly increased by P. gingivalis associated ligation and decreased by fenofibrate treatment in WT mice but not in PPARα KO mice. Conclusion This study suggests that PPARα plays an essential role in periodontitis.

Purpose/Objectives This study aimed to determine how the COVID‐19 pandemic and extensive use of personal protective equipment (PPE) have affected the perception of the practice of dentistry in an urban dental school in the USA. Methods In 2021, an electronic cross‐sectional questionnaire was sent to school faculty via email, while predoctoral, clinical dental students were invited to participate during clinical group meetings. Data were analyzed using descriptive statistics. Results Sixty‐six faculty and 209 students completed the questionnaire (n = 275, response rate = 39%). The faculty self‐identified into two groups: dentists who only teach (teaching faculty, n = 33) and dentists who teach and also work in outside clinics (practicing faculty, n = 33). Practicing faculty (45.5%) were significantly more pessimistic about the future of dentistry than the other two groups. Students were the least concerned with treating COVID‐19 patients compared to other groups and only 15.8% of students reported a change in enthusiasm toward dentistry. Practicing faculty did not feel that extra PPE presented a physical challenge. Teaching faculty were least alarmed by extra PPE and least concerned about PPE increasing patient stress. More faculty were in favor of vaccination requirements (90.9%) than students (73.7%). Conclusions Neither COVID‐19 nor the use of extensive PPE negatively affected the participants’ perception of the future of dentistry. Most participants felt safe wearing extra PPE during the pandemic but were concerned about the negative environmental effects. Students did not feel strongly that vaccination should be a requirement for clinical dentists and staff.