Oral Biology and Oral Pathology Commons^™

Dental Disparities: An Analysis Of Dental Caries Risk Factors Promoting Disparities Between Rural And Urban Communities In Nebraska, Nick Lounsbery

Honors Program: Senior Projects (Public)

The prevalence of dental caries in the United States remains a public health concern, as it is one of the most common chronic conditions across people of all ages. Research shows that preventative measures including brushing, fluoridated water, and regular checkups are effective strategies to mitigate tooth decay. However, there appears to be a divide between rural and urban populations, as the presence of dental cavities is significantly greater in remote areas in the State of Nebraska. Research methods used in this analysis included analyzing accredited academic literature to illustrate how cavities form from a biochemical perspective. Research methods also …

Education, Beliefs, And Health Literacy Of Care Providers On Mouth Care Of Older Adults, Molly Lakin

Honors Program: Senior Projects (Public)

Oral health is important to one’s overall health and quality of life as it can lead to chronic illnesses such as cardiovascular disease, stroke, and neurodegenerative disorders (Haumschild et al. 2021). In long-term care facilities, it is important that dependent older adults are provided mouth care to maintain their oral health and decrease their chances of developing a chronic illness; however, there are barriers affecting the level, quality, and quantity of mouth care being provided in these facilities. A survey was developed to look at the education, beliefs, and health literacy of care providers on providing mouth care in hopes …

Comparisons Of Oral, Intestinal, And Pancreatic Bacterial Microbiomes In Patients With Pancreatic Cancer And Other Gastrointestinal Diseases, Mei Chung, Naisi Zhao, Richard Meier, Devin C. Koestler, Guojun Wu, Erika De Castillo, Bruce J. Paster, Kevin Charpentier, Jacques Izard, Karl T. Kelsey, Dominique S. Michaud

Department of Food Science and Technology: Faculty Publications

Background: Oral microbiota is believed to play important roles in systemic diseases, including cancer. Methods: We collected oral samples (tongue, buccal, supragingival, and saliva) and pancreatic tissue or intestinal samples from 52 subjects, and characterized 16S rRNA genes using high-throughput DNA sequencing.

Results: Bray–Curtis plot showed clear separations between bacterial communities in the oral cavity and those in intestinal and pancreatic tissue samples. PERMANOVA tests indicated that bacterial communities from buccal samples were similar to supragingival and saliva samples, and pancreatic duct samples were similar to pancreatic tumor samples, but all other samples were significantly different from each …

Correlation Of Periodontal Pathogens In Concurrent Endodontic-Periodontal Diseases, Amela Lačević, Federico Foschi, Lejla Pojskić, Naris Pojskić, Kasim Bajrović, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Objectives: This study investigated the correlation between Tannerella forsythia, Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans at dual sites in concurrent endodonticperiodontal diseases.

Material and methods: Samples were collected from endodontium and periodontium in cases of concurrent endodontic-periodontal diseases from thirty participants. The sensitivity and specificity of SYBR Green real-time PCR was used to identify the targeted species. Absolute number of targeted genome copies in tested samples were extrapolated from respective calibration curve.

Results: No statistical difference was found in the number of detected endodontic-periodontal pathogens between the endodontium and periodontium. The Pearson test …

Microbiota, Oral Microbiome, And Pancreatic Cancer, Dominique S. Michaud, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Only 30% of patients diagnosed with pancreatic cancer survive one year post-diagnosis. Progress in understanding the causes of pancreatic cancer has been made, including solidifying the associations with obesity and diabetes, and a proportion of cases should be preventable through lifestyle modifications. Unfortunately, identifying reliable biomarkers of early pancreatic cancer has been extremely challenging, and no effective screening modality is currently available for this devastating form of cancer. Recent data suggest the microbiota may play a role in the disease process, but many questions remain. Future studies focusing on the human microbiome, both etiologically and as a marker of disease …

A Prospective Study Of Periodontal Disease And Risk Of Gastric And Duodenal Ulcer In Male Health Professionals, Matthew R. Boylan, Hamed Khalili, Edward S. Huang, Dominique S. Michaud, Jacques Izard, Kaumudi J. Joshipura, Andrew T. Chan

Department of Food Science and Technology: Faculty Publications

Periodontal disease is characterized by microbial shifts within the oral cavity and chronic inflammation of the gingival tissue, and can lead to tooth loss. Several studies support an association between periodontal disease and risk of chronic systemic conditions, including vascular disease, chronic obstructive pulmonary disease, diabetes mellitus, and cancer, including gastric adenocarcinoma. These associations may be mediated by systemic inflammation, the immune response to periodontal infection, or direct invasion by pathogens. Previous studies of periodontal disease and risk of peptic ulcer have been limited by cross-sectional design, diagnoses that were not confirmed by medical record review, and a lack of …

Plasma Antibodies To Oral Bacteria And Risk Of Pancreatic Cancer In A Large European Prospective Cohort Study, Dominique S. Michaud, Jacques Izard, Charlotte S. Wilhelm-Benartzi, Doo-Ho You, Verena A. Grote, Anne Tjønneland, Christina C. Dahm, Kim Overvad, Mazda Jenab, Veronika Fedirko, Marie Christine Boutron-Ruault, Françoise Clavel- Chapelon, Antoine Racine, Rudolf Kaaks, Heiner Boeing, Jana Foerster, Antonia Trichopoulou, Pagona Lagiou, Dimitrios Trichopoulos, Carlotta Sacerdote, Sabina Sieri, Domenico Palli, Rosario Tumino, Salvatore Panico, Peter Siersema, Petra Hm Peeters, Eiliv Lund, Aurelio Barricarte, José-María Huerta, Esther Molina-Montes, Miren Dorronsoro, J. Ramón Quirós, Eric J. Duell, Weimin Ye, Malin Sund, Björn Lindkvist, Dorthe Johansen, Kay-Tee Khaw, Nick Wareham, Ruth C. Travis, Paolo Vineis, H. Bas Bueno-De-Mesquita, Elio Riboli

Department of Food Science and Technology: Faculty Publications

Objective: Examine the relationship between antibodies to 25 oral bacteria and pancreatic cancer risk in a prospective cohort study.

Design: We measured antibodies to oral bacteria in prediagnosis blood samples from 405 pancreatic cancer cases and 416 matched controls, nested within the European Prospective Investigation into Cancer and Nutrition study (EPIC). Analyses were conducted using conditional logistic regression and additionally adjusted for smoking status and body mass index.

Results: Individuals with high levels of antibodies against Porphyromonas gingivalis ATTC 53978, a pathogenic periodontal bacteria, had a 2-fold higher risk of pancreatic cancer than individuals lower levels of …

Neisseria Oralis Sp. Nov., Isolated From Healthy Gingival Plaque And Clinical Samples, William J. Wolfgang, Teresa V. Passaretti, Reashma Jose, Jocelyn Cole, An Coorevits, Andrea N. Carpenter, Sherly Jose, Anita Van Landschoot, Jacques Izard, Donna J. Kohlerschmidt, Peter Vandamme, Floyd E. Dewhirst, Mark A. Fisher, Kimberlee A. Musser

Department of Food Science and Technology: Faculty Publications

A polyphasic analysis was undertaken of seven independent isolates of gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida, and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbor, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the …

Etiology Of Noncarious Cervical Lesions, Caren M. Barnes

College of Dentistry: Faculty Publications

As the number of older adults in the United States continues to grow, this change in patient demographics will profoundly affect the practice of dental hygiene. Not only are there more older adults, but they are also retaining more of their natural teeth than ever before. The risk of alveolar bone loss; gingival recession, which can lead to exposed cervical and root areas of the teeth; and tooth wear all increase with age. The confluence of these factors raises the risk of noncarious cervical lesions (NCCLs).

The prevalence of NCCLs is growing, largely due to the rising numbers of older …

Composition Of The Adult Digestive Tract Bacterial Microbiome Based On Seven Mouth Surfaces, Tonsils, Throat And Stool Samples, Nicola Segata, Susan Kinder Haake, Peter Mannon, Katherine P. Lemon, Levi Waldron, Dirk Gevers, Curtis Huttenhower, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Background: To understand the relationship between our bacterial microbiome and health, it is essential to define the microbiome in the absence of disease. The digestive tract includes diverse habitats and hosts the human body’s greatest bacterial density. We describe the bacterial community composition of ten digestive tract sites from more than 200 normal adults enrolled in the Human Microbiome Project, and metagenomically determined metabolic potentials of four representative sites.

Results: The microbiota of these diverse habitats formed four groups based on similar community compositions: buccal mucosa, keratinized gingiva, hard palate; saliva, tongue, tonsils, throat; sub- and supra-gingival plaques; …

Pathogenicity Of Treponema Denticola Wild-Type And Mutant Strain Tested By An Active Mode Of Periodontal Infection Using Microinjection, Jacques Izard, Hajime Sasaki, Ralph Kent

Department of Food Science and Technology: Faculty Publications

The available passive mode of periodontal infections in mice requires high efficiency of bacterial attachment and invasiveness and is not always suitable to test the pathogenicity of genetically engineered mutant strains. We developed an active mode of oral infection, using microinjection in the marginal gingiva of mice, to test the pathogenicity of a genetically engineered Treponema denticola mutant strain deficient in intermediate-like filaments, compared to the wild-type strain. This targeted mode of infection inoculates the bacterial strain to be tested directly at a lesion site (needle entry point) located at the future periodontal lesion site. The efficiency of T. …

The Human Oral Microbiome, Floyd E. Dewhirst, Tuste Chen, Jacques Izard, Bruce J. Paster, Anne C. R. Tanner, Wen-Han Yu, Abirami Lakshmanan, William G. Wade

Department of Food Science and Technology: Faculty Publications

The human oral cavity contains a number of different habitats, including the teeth, gingival sulcus, tongue, cheeks, hard and soft palates, and tonsils, which are colonized by bacteria. The oral microbiome comprises over 600 prevalent taxa at the species level, with distinct subsets predominating at different habitats. The oral microbiome has been extensively characterized by cultivation and culture-independent molecular methods such as 16S rRNA cloning. Unfortunately, the vast majority of unnamed oral taxa are referenced by clone numbers or 16S rRNA GenBank accession numbers, often without taxonomic anchors. The first aim of this research was to collect 16S rRNA gene …

The Human Oral Microbiome Database: A Web-Accessible Resource For Investigating Oral Microbe Taxonomic And Genomic Information, Tsute Chen, Wen-Han Yu, Jacques Izard, Oxana V. Baranova, Abirami Lakshmanan, Floyd E. Dewhirst

Department of Food Science and Technology: Faculty Publications

The human oral microbiome is the most studied human microflora, but 53% of the species have not yet been validly named and 35% remain uncultivated. The uncultivated taxa are known primarily from 16S rRNA sequence information. Sequence information tied solely to obscure isolate or clone numbers, and usually lacking accurate phylogenetic placement, is a major impediment to working with human oral microbiome data. The goal of creating the Human Oral Microbiome Database (HOMD) is to provide the scientific community with a body site-specific comprehensive database for the more than 600 prokaryote species that are present in the human oral cavity …

Building The Genomic Base-Layer Of The Oral “Omic” World, Forsyth Metagenomic Support Consortium, Jacques Izard

Department of Food Science and Technology: Faculty Publications

With the shift of molecular technologies directed toward the understanding of greater biological complexity of the oral cavity, a knowledge gap was created by the lack of genomic data from the diverse oral microorganisms. To facilitate and enable the interpretation of metagenomic, transcriptomic, and proteomic data generated or soon to be generated from oral biofilms, we are providing reference genomic information from phylogenetically diverse oral bacterial isolates. This work, initiated by the National Institute of Dental and Craniofacial Research as an isolated effort, is now part of the Human Microbiome Project. The goal of this effort is the public release …

Killing Of Treponema Denticola By Mouse Peritoneal Macrophages, P. Gaibani, C. Vocale, S. Ambretti, F. Cavrini, Jacques Izard, L. Miragliotta, M. T. Pellegrino, V. Sambri

Department of Food Science and Technology: Faculty Publications

Treponema denticola has been identified as an important cause of periodontal disease and hypothesized to be involved in extra-oral infections. The objective of this study was to investigate the role of T. denticola cell length and motility during mouse peritoneal macrophages in vitro uptake. Macrophages, incubated under aerobic and anaerobic conditions, produced a similar amount of TNF-α when stimulated with Escherichia coli LPS. The uptake of FlgE- and CfpA-deficient mutants of T. denticola was significantly increased compared with the wild-type strain, due to cell size or lack of motility. Opsonization with specific antibodies considerably improved the treponemes’ uptake. …

An Experimental Approach To Modeling The Strength Of Canine Teeth, Patricia W. Freeman, Cliff A. Lemen

School of Natural Resources: Faculty Publications

The strength of canine teeth in several carnivores is found through direct fracture experiments. The average forces required to break the canines of adult animals are coyote 1170 N, red fox 533 N, bobcat 737 N and raccoon 512 N. Stresses created in teeth at the breaking load are predicted by finite-element analysis and beam theory. The ultimate tensile stress sustainable in these teeth is 338 MPa in adult animals. The large pulp cavity in the canines of young animals significantly weakens the bases of their teeth (by about 25%), but as the animal ages the pulp cavity decreases and …

Treponema Denticola In Disseminating Endodontic Infections, F. Foschi, Jacques Izard, H. Sasaki, V. Sambri, C. Prati, R. Müller, P. Stashenko

Department of Food Science and Technology: Faculty Publications

Treponema denticola is a consensus periodontal pathogen that has recently been associated with endodontic pathology. In this study, the effect of mono-infection of the dental pulp with T. denticola and with polymicrobial “red-complex” organisms (RC) (Porphyromonas gingivalis, Tannerella forsythia, and T. denticola) in inducing disseminating infections in wild-type (WT) and severe-combined-immunodeficiency (SCID) mice was analyzed. After 21 days, a high incidence (5/10) of orofacial abscesses was observed in SCID mice mono-infected with T. denticola, whereas abscesses were rare in SCID mice infected with the red-complex organisms or in wild-type mice. Splenomegaly was …

Periplasm Organization In Treponema Denticola As Studied By Cryo-Electron Tomography, Jacques Izard, C.-E. Hsieh, C. A. Mannella, Ronald J. Limberger, M. Marko

Department of Food Science and Technology: Faculty Publications

As a spirochete, the genus Treponema is one of the few major bacterial groups whose natural phylogenic relationships are evident at the level of gross phenotypic characteristics such as their morphology. Treponema spp. are highly invasive due to their unique motility in dense media, and their ability to penetrate cell layers. This feature is associated with the helical cell body and the presence of flagellar filaments in the periplasm. Treponema denticola is an oral pathogen involved in endodontic infections and periodontal diseases. The presence and quantity of T. denticola in the subgingival biofilm is correlated with the severity of periodontal …

Genetic And Structural Analyses Of Cytoplasmic Filaments Of Wild-Type Treponema Phagedenis And A Flagellar Filament-Deficient Mutant, Jacques Izard, William A. Samsonoff, Mary Beth Kinoshita, Ronald J. Limberger

Department of Food Science and Technology: Faculty Publications

Unique cytoplasmic filaments are found in the treponeme genus of spirochete bacteria. Their function is unknown, but their location underneath the periplasmic flagellar filaments (PFF) suggests a role in motility and/or cell structure. To better understand these unique structures, the gene coding for the cytoplasmic filaments, cfpA, was identified in various treponemal species. Treponema phagedenis cfpA was 2,037 nucleotides long, and the encoded polypeptide showed 78 to 100% amino acid sequence identity with the partial sequence of CfpA from T. denticola, T. vincentii, and T. pallidum subsp. pertenue. Wild-type T. phagedenis and a …

Insertional Inactivation Of Treponema Denticola Tap1 Results In A Nonmotile Mutant With Elongated Flagellar Hooks, Ronald J. Limberger, Linda L. Slivienski, Jacques Izard, William A. Samsonoff

Department of Food Science and Technology: Faculty Publications

The treponemal fla operon is comprised of numerous motility-related genes; however, the initial gene of this operon, tap1, has no known function. A recently developed system to generate specific mutants in Treponema denticola was utilized to determine if Tap1 was essential for motility. T. denticola tap1 and flanking DNA were identified, cloned, and sequenced, and a suicide plasmid that contained tap1 interrupted with an erythromycin resistance cassette (ermF and ermAM) was constructed. Because of potential polar effects from this cassette, a second plasmid that contained tap1 interrupted with a modified erythromycin resistance cassette that lacked the putative ermF transcription …

Results Of A Head And Neck Examination: Evaluation Of A Tumor Of The Floor Of The Mouth, Caren M. Barnes, Kenneth W. Nelson, Gary H. Conover

College of Dentistry: Faculty Publications

This article reviews a solitary, well-defined tumor of the floor of the mouth. The tumor presented as a raised, elevated, sessile mass that was freely movable and soft to. the touch. The case illustrates the importance of performing a thorough head and neck examination, and formulating a differential diagnosis if any abnormality is detected. The clinical features, histopathology and responsibility of the dental hygienist in performing a thorough head and neck examination is reviewed.