Root canal and periapical pathosis develops upon introduction of bacteria or bacterial products into the root canal space. Root canal infections are polymicrobial and consist of approximately 90% anaerobic organisms. The root canal space of a necrotic pulp acts as a closed environment as it lacks collateral circulation. The hypothesis of my research is changes in microbial communities in root canals toward a more virulent state occur as a result of specific bacterial interactions and physicochemical changes in that environment.
Specific aims i nclude 1) examining potential interactions between endodontic pathogens and other oral bacteria in the development of mixed microbial communities and 2) determine the effects of physicochemical changes in the microenvironment on the development of microbial communities and expression of virulence determinants. Findings suggest that 1) stimulatory and/or inhibitory factors may be produced by specific bacteria in mixed batch culture affecting the development of a community of organisms, 2) oxygen protective factors of blood are related to the red blood cells and the lysis of the RBC stimulates the growth yield of P. endodontalis in an anaerobic environment, and 3) addition of blood alters the growth and development of microbial communities associated with endodontic pathosis. Future studies are to examine the mechanism of iron acquisition from RBI's and the potential role of hemolysin activity.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Unknown (K16)
Project #
2K16DE000175-12
Application #
6238329
Study Section
Project Start
1997-07-01
Project End
1998-06-30
Budget Start
1996-10-01
Budget End
1997-09-30
Support Year
12
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of Iowa
Department
Type
DUNS #
041294109
City
Iowa City
State
IA
Country
United States
Zip Code
52242
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