Browsing Theses and Dissertations by Author "Sedghi, Lea Maryam"
The Effect Of Dietary Texture On The Composition Of The Murine Dental MicrobiomeSedghi, Lea MaryamDental plaque exists as a highly complex biofilm community that is known to lead to various states of dental disease. The pathogenicity of the dental biofilm is directly related to the species residing within the biofilm. While some oral biofilm communities are associated with states of oral health, others are interchangeable with states of dental disease and oral pathology. The microbial community population of the oral cavity is heavily influenced by host diet composition. Diet composition contributes to the establishment of differing microbial communities in terms of relative species abundance and diversity. Some diets are associated with oral bacteria related to a healthy oral environment while others show association with microbes that are related to states of dental disease. Many studies have focused on the significance of dietary carbohydrate content on dental disease. However, the effect of dietary texture on dental disease has been comparatively overlooked. This study utilizes 16S rRNA analysis to better understand the influence of diet texture on oral microbial populations among the dental enamel surface in terms of microbial diversity and abundance. Four diet groups—1) Base (Control), 2) Base+Fiber, 3) Base+Sugar, and 4) Base+Fiber+Sugar—are used to determine if dietary texture as well as carbohydrate content affects changes within the oral microbiome to potentially influence dental disease. This study ultimately seeks to offer insight into whether the loss of dietary texture in the Western diet has acted as a stimulus towards increased incidence of dental disease over time. We found that dietary fiber, and not sugar, had a significant effect on dental microbiome alpha and beta diversity at the genus level. Additionally, beta diversity was significantly affected at the phylum level. Consistent with this finding fiber, and not sugar, also explained significant changes in microbial taxonomic abundance at the genus level. These changes were microbe-specific for each dietary group. A general finding was that fiber had a stronger influence on microbial diversity and abundance than did sugar. The only significant effects sugar demonstrated in this experiment were in its interaction with dietary fiber. Further analysis using metagenomic shotgun sequencing should be utilized to better understand the metabolic impact of the changes observed in this preliminary study.