A technique for the bacteriologic investigation of the physiologic gingival crevice

Typewritten.Thesis (M.Sc.D.)--Boston University, March, 1965. Note: Page 111 is missing.Bibliography: p. 99-109

Porphyromonas gingivalis Produce Neutrophil Specific Chemoattractants Including Short Chain Fatty Acids

Neutrophil migration from blood to tissue-residing microbes is governed by a series of chemoattractant gradients of both endogenous and microbial origin. Periodontal disease is characterized by neutrophil accumulation in the gingival pocket, recruited by the subgingival biofilm consisting mainly of gram-negative, anaerobic and proteolytic species such as Porphyromonas gingivalis. The fact that neutrophils are the dominating cell type in the gingival pocket suggests that neutrophil-specific chemoattractants are released by subgingival bacteria, but characterization of chemoattractants released by subgingival biofilm species remains incomplete. In the present study we characterized small (< 3 kDa) soluble chemoattractants released by growing P. gingivalis, and show that these are selective for neutrophils. Most neutrophil chemoattractant receptors are expressed also by mononuclear phagocytes, the free fatty acid receptor 2 (FFAR2) being an exception. In agreement with the selective neutrophil recruitment, the chemotactic activity found in P. gingivalis supernatants was mediated in part by a mixture of short chain fatty acids (SCFAs) that are recognized by FFAR2, and other leukocytes (including monocytes) did not respond to SCFA stimulation. Although SCFAs, produced by bacterial fermentation of dietary fiber in the gut, has previously been shown to utilize FFAR2, our data demonstrate that the pronounced proteolytic metabolism employed by P. gingivalis (and likely also other subgingival biofilm bacteria associated with periodontal diseases) may result in the generation of SCFAs that attract neutrophils to the gingival pocket. This finding highlights the interaction between SCFAs and FFAR2 in the context of P. gingivalis colonization during periodontal disease, but may also have implications for other inflammatory pathologies involving proteolytic bacteria

Microbiome composition comparison in oral and atherosclerotic plaque from patients with and without periodontitis

There is no conclusive evidence regarding a causal relationship between periodontitis and atherosclerosis. In this study, we examined the microbiome in the oral cavity and atheromatous plaques from atherosclerosis patients with or without periodontitis to investigate the role of oral bacteria in the formation of atheromatous plaques. We chose four patients with and without periodontitis, who had undergone carotid endarterectomy. Bacterial samples were extracted from the tongue surface, from periodontal pocket (during the oral examination), and from the atheromatous plaques (APs). We investigated the general and oral conditions from each patient and performed next-generation sequencing (NGS) analysis for all bacterial samples. There were no significant differences between both groups concerning general conditions. However, the microbiome patterns of the gingival pocket showed differences depending on the absence or presence of periodontitis, while those of the tongue surface were relatively similar. The microbiome pattern of the atheromatous plaques was entirely different from that on the tongue surface and gingival pocket, and oral bacteria were seldom detected. However, the microbiome pattern in atheromatous plaques was different in the presence or absence of periodontitis. These results suggested that oral bacteria did not affect the formation of atheromatous plaques directly

Prevalence of halitosis and evaluation of etiological factors in a Turkish subpopulation

Aim: The purpose of this study was to estimate the prevalence of halitosis in an adult Turkish subpopulation and to assess the relationship between halitosis and sociodemographics, self reported halitosis, etiological factors, by employing standardized procedures for measurement of halitosis. Methods: The study included 459 subjects who referred to oral diagnosis clinic of Gazi University Faculty Of Dentistry. The questionnaire including the questions of sociodemographic data, halitosis complaints, oral hygiene practices, extrinsic causes and extra-oral causes. In the clinical examination, dentition and soft tissues were evaluated. Tongue coating status, periodontal index, gingival index and plaque index were recorded. Values for halitosis were assessed by measurement of volatile sulfur compounds (VSC) using portable sulphide monitor. Results: The questionnaire revealed that 46.6% of the subjects suffered from halitosis and females sufferred from halitosis more frequently than males. The prevalence of halitosis was 50.7% . A significant correlation was found between halitosis and tongue coating, periodontitis, gingivitis though PI did not affect halitosis. There were not significant correlations between halitosis and oral hygiene practices, extrinsic causes and extra-oral causes. Conclusion: This study showed that there was a high prevalence of halitosis in the Turkish population and the most important factors that influence halitosis were intra-oral causes

A volumetric analysis of sulcular fluid flow relative to teeth undergoing periodontal prosthesis

Thesis (M.Sc.D.)--Boston University, School of Graduate Dentistry, 1971.Bibliography included.This study was undertaken to determine whether there was any volumetric change in the amount of sulcular fluid flow in the gingival crevice, prior to, and subsequent to the placement of fixed periodontal prostheses. The volume of sulcuf ar fluid was measured and assayed by the use of disposable plastic syringes graded in millimeters: I. Prior to tooth preparation. II. Approximately two to four weeks after temporization of individual and multiple prosthetic abutments. III. Approximately two weeks after final insertion of fixed prosthesis. The study was performed on ten human patients in clinical periodontal health. The results statistically showed that the amount of fluid flow increased after temporization of prosthetic abutments and decreased slightly following insertion of the final fixed prosthesis

Clinical Significance of Gingival Fluid in Periodontal Diseases

Gingival fluid, sulcular fluid, gingival crevicular (crevice) fluid and gingival exdute are the substances which seep out of the gingival sulcus or periodontal pocket. Evidence has been accumulated that the amount and make-up of the fluid changes along the clinical situation. Therefore, the author made an overview of the latest studies relating to gingival fluid and its clinical significance in this paper. The clinical significance of gingival fluid can be summarized as follows. 1. Defense against periodontal tissues 1) Washes bacillus and remaining food material out of the gingival sulcus (flows them out); 2) Possesses antimicrobial properties (leukocytes, gamma globulin, lysozyme, etc.); 3) Improves adhesion of the epithelial attachment to the tooth; 2. Destruction of periodontal tissues 1) Supplies the medium (protein, calcium) which makes bacterial growth possible; 2) Contributes to the formation of dental plaque and calculus; Based on these facts, the measurement and analysis of gingival fluid appears to be useful in early and effective evaluation of the internal condition of tissues in periodontal disease. It would be extremely effective in motivating patients