Magister Scientiae Dentium - MSc(Dent) / Between September 1992 and August 1995, all patients with haematological malignancies who were treated as in-patients in the Haematology Unit at Groote Schuur Hospital received a twice weekly, oral and perioral examination. Sixty patients were monitored while following the traditional hospital oral care protocol (chlorhexidine, hydrogen peroxide, sodium bicarbonate, thymol glycol, benzocaine mouthrinse and nystatin). The mouth care protocol was then changed (protocol A = chlorhexidine, benzocaine lozenges, amphotericin B lozenges) and patients monitored until the sample size matched that of the hospital mouth care regimen (n = 60). A further 60 patients were then monitored using a third protocol (protocol B = benzydamine hydrochloride, chlorhexidine, benzocaine lozenges, amphotericin B lozenges). A statistically significant reduction in oral complications was found upon introduction and maintenance of protocols A and B. The findings of this study suggest that improved oral care and a structured oral care routine reduces the number of oral complications associated with chemo- and radiotherapy. / Medical Research council

Periodontal inflammation is a hallmark of periodontitis and a primary driver of progressive periodontal tissue destruction. In addition, inflammation is hypothesized as a critical mechanistic intermediate linking periodontal disease to systemic inflammation and extra-oral disease outcomes. However, most of the commonly used measures of periodontitis, for research and/or surveillance purposes, focus on quantifying the periodontal tissue loss (i.e., gingival recession (GR) and clinical attachment loss (CAL)). There are few indices that focus on quantifying periodontal inflammation in the periodontal literature, and there are inherent limitations in the way they are calculated. The Periodontal Inflamed Surface Area (PISA) is a composite measure that incorporates bleeding on probing (BOP) and other measures of periodontal disease to quantify the amount of periodontal inflamed surfaces. This dissertation examined PISA as a useful measure that attempted to quantify periodontal inflammation, and it is divided into three parts. The first paper is a scoping review focused on reviewing the relevant literature around PISA since its introduction to the literature in 2008. The second paper is an empirical paper that examined the psychometric properties of PISA compared to other measures of periodontitis. The third paper is another empirical study that explored how PISA correlated with some biological features of periodontitis, including the subgingival microbial profile, systemic immune response, and selected dysbiosis indices. The empirical papers utilized data from two population-based cohorts: the Oral Infections, Glucose Intolerance, and Insulin Resistance Study (ORIGINS) and the Washington Heights Inwood Community Aging Project's Ancillary Study of Oral Health (WHICAP-OH). The review found that PISA was primarily utilized in studies that looked at oral-systemic health connections, with results that mostly confirmed the associations between periodontal disease and systemic health. However, most evidence suffered from methodological concerns that could limit the validity and generalizability of results. The psychometrics analyses showed that PISA had good sensitivity, specificity, and accuracy in identifying patients with periodontitis. The latent factor analyses suggested a multi-level three-factor model showing PISA to cluster with bleeding on probing in the same factor that indicates an inflammation component of the unobserved periodontal disease status. The third paper showed that PISA was significantly associated with alpha diversity indices (Shannon's, Simpson's, and Faith's phylogenetic diversity) and two of the dysbiosis indices in both cohorts. The strength of associations and amount of variance explained in some of the biological features were higher for PISA than other measures of periodontitis. The evidence from this dissertation suggests that PISA is a valuable index that describes periodontal inflammation and has good psychometric properties. Future research can explore the replication of our methods in other cohorts to expand the validity and utility of PISA in periodontal literature.

Septic pulmonary embolization (SPE) is a rare but serious disorder. It is a well-recognized potential problem in the settings of tricuspid valve endocarditis, septic thrombophlebitis, infected central venous catheters, and postanginal septicemia. Less well documented is the occurrence of SPE in patients with periodontal disease without suppurative thrombophlebitis of the great vessels of the neck. We report a patient with SPE in whom periodontal disease was the only identifiable nidus of infection and review the literature regarding the four other patients reported to have suffered this complication.

Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Nutrition and Food Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Bibliography: leaves 176-193. / by Henry M. Mallek. / Ph.D.

Prevotella intermedia/nigrescens group bacteria are Gram-negative, non-motile, anaerobic rods abundant in the subgingival microbiome of human periodontitis patients, and relatively sparse in persons with periodontal health. P. intermedia/nigrescens may be inadequately suppressed in periodontal pockets with conventional mechanical-surgical forms of periodontal therapy. Therefore, short-term systemic antibiotic therapy is often recommended in the treatment of recalcitrant (refractory) severe periodontitis patients where high numbers of P. intermedia/nigrescens persist in the subgingival microbiota. Limited available data suggests that the antibiotic sensitivity profile of periodontal P. intermedia/nigrescens has changed over time among severe periodontitis patients in the United States, with increasing levels of antibiotic resistance reported. These findings have potentially important clinical implications for dental professionals and their severe periodontitis patients which need further confirmation and clarification. To further expand knowledge on this clinically relevant issue, the purpose of the present study was to determine and compare over a 10-year period (2011 versus 2021) the prevalence of in vitro resistance of periodontal P. intermedia/nigrescens to the antibiotics amoxicillin, metronidazole, clindamycin, and doxycycline. / Oral Biology

No description available.

Frailty is defined as a biological syndrome marked by reduced physiological reserve and heightened vulnerability to stressors, leading to adverse health outcomes like dependency, functional impairment, cognitive decline, and mortality. While various conditions have been associated with frailty, oral health is one of them. However, the precise relationship and the underlying pathways through which oral health conditions may be associated with frailty remain unclear. Limitations such as small sample sizes, inadequate control for confounders, inconsistent results across studies, and variations in frailty assessment methods have contributed to the inconclusiveness of this relationship. Considering these limitations, this dissertation intends to address them by using a rigorous cohort with a robust design, which will allow for a larger sample size, appropriate confounder assessment, and the opportunity to create a practical frailty index (FI) using data from this cohort. This approach enables a comprehensive investigation of the association between clinical, functional, and microbiological oral health and frailty, both cross-sectionally and longitudinally (12 years of follow-up). Furthermore, this study aims to conduct an initial exploration of the mediating effects of inflammatory biomarkers in this relationship.Three specific aims were pursued to achieve this goal. Firstly, a systematic review was conducted to critically summarize the existing evidence on the association between poor oral health and frailty, assessed through any frailty index instrument. Subsequently, two analytical aims were undertaken to delve into the association between oral health and frailty. The initial analytical aim comprised two parts. The first part focused on creating and validating a population frailty index score using data from the Oral Infections and Vascular Disease Epidemiology Study (INVEST). The second part aimed to investigate, cross-sectionally, whether poor oral health independent of factors such as sex, age, occupation, educational level, marital status, and smoking is positively associated with frailty. Additionally, the study aimed to test the robustness and replicability of both the FI and the cross-sectional relationship, utilizing a smaller set of oral data from the Chilean National Health Survey conducted in 2016-2017. The second analytical aim was to explore the prospective association between oral health – assessed clinically, functionally, and microbiologically- and frailty, using the INVEST cohort with its 12 years of follow-up and repeated measures for the exposure, confounders and outcome. As a secondary aim, we explored the mediating effects of select inflammatory biomarkers in this relationship. The systematic review identified 11 studies that investigated the relationship between oral health and frailty, utilizing the FI as an instrument for assessing frailty. All these studies were cross-sectional, and the FI employed in them encompassed a range of deficits, varying from 32 to 76 items. The most frequently incorporated constructs in the frailty index were comorbidities, cognitive impairment, activities of daily living (ADL and/or IADL), functional limitations or abilities, anthropometry, depressive symptoms, and self-reported health status. In terms of the association between oral health and frailty, the review showed that a lower number of teeth, poor self-reported oral health, and experiencing chewing or oral cavity pain were associated with an increased likelihood of frailty, as indicated by any FI. Notably, no studies reported an association between periodontal disease, cavities, use of dental prostheses, and frailty. The second aim showed that within the U.S. population, functional oral health (assessed as the number of teeth and higher number of occlusive tooth pairs) was associated with frailty. Similarly, among the Chilean population aged 55 years and older, frailty was also associated with functional oral health (lower number of additional teeth, wearing dental prostheses, and not having a functional dentition). This study also showed that the inclusion of periodontal microbiota in the regression models improved the model’s fit, suggesting that this microbiota may play a role in the association between oral health and frailty. Finally, the third aim showed that after 12 years of follow-up, a higher incidence of frailty was associated with functional and clinical oral health. In fact, people who exhibited a lower number of additional teeth, had less than 21 teeth, wearing complete dental prostheses, and had periodontal disease had a higher incidence of frailty. Moreover, CRP, IL-6, and TNF- exhibited small, but not statistically significant, effects as potential mediators between oral health and frailty. These findings suggest the potential for further research to explore the action of other inflammatory biomarkers and pathways through which oral health may be associated with frailty.

Thesis (M.D.S.)--University of Hong Kong, 1988. / Also available in print.

published_or_final_version / Dentistry / Master / Master of Dental Surgery

published_or_final_version / Dentistry / Master / Master of Dental Surgery