Bacteria Commons^™

Development Of Periapical Lesions In Immunosuppressed Rats, Phillip A. Waterman Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The pathogenesis of periapical lesions is the interaction of the oral flora with the existing host defenses. The role of bacteria has been established in endodontic disease but the contribution of the host defenses in periapical lesion formation is less clear. The purpose of this study was to compare periapical lesion development in immunosuppressed rats with that in normal rats. Thirty-five, eight-week old Sprague-Dawley rats were equally divided into seven groups. Groups 1, 2, and 3 were given weekly injections of Cytoxan, an immunosuppressive agent. Groups 4, 5, and 6 received no immunosuppressive therapy. Group 7 served as a control, …

Concentration Of Leukotrienes B4 And C4 In Human Periradicular Lesions, Elisabetta Cotti

Loma Linda University Electronic Theses, Dissertations & Projects

The 5-lipoxygenase metabolites of arachidonic acid such as leukotrienes (LT) B₄ and C₄, are potent mediators of inflammation. The purpose of this investigation was to determine the concentrations of LTB₄ and LTC₄ in human periradicular lesions. Specimens from asymptomatic and symptomatic patients were obtained and immediately frozen in liquid nitrogen. Periradicular tissues from unerupted third molars as well as chronically inflamed gingival tissues were also obtained, frozen and were used as negative and positive controls respectively. The concentrations of LTB₄ and LTC₄ were determined by the reverse phase high pressure liquid chromatography. Representative …

Immunologic Mechanisms Involved With Human Endodontic Lesions, Sunita V. Prabhu

Loma Linda University Electronic Theses, Dissertations & Projects

Endodontic or root canal infection results in immunologic changes in periapical region, which causes the destruction of pulpal and periapical tissue. No definitive study has identified a specific organism or a group of organisms as a etiological agents. Past studies have indicated that immunoglobulin E play a significant role in the pathogenesis of periapical lesions. The presence of this factor suggests that some of the endodontic flare-ups may be IgE-mediated hypersensitivity reactions. Antibody levels of IgA have been quantitatively measured by ELISA and IgE by modified RAST assay, against eleven oral bacteria which are routinely isolated from such lesions. The …

Effects Of Oral Hygiene Measures On Clinical And Microbiological Parameters Of Periodontal Disease, Bruno Loos

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of a 12-week period of oral hygiene alone on gingival conditions and subgingival microflora in 15 patients with severe periodontitis were investigated. In addition, subgingival microsamples were compared during this oral hygiene phase with those obtained 1 week after debridement. Clinical measurements and subgingival samples from selected sites were taken at week 0 (baseline), week 6, and week 12. Microbial samples were also taken at week 13, that is, one week following debridement. At week 0 the patients were instructed in supragingival plaque control and at week 6 the hygiene regimen was supplemented with the subgingival use of …

The Determination Of Antibody Levels In Endodontic Patients Against Eleven Microorganisms Using Ifa And Elisa Techniques, William C. Payne

Loma Linda University Electronic Theses, Dissertations & Projects

Endodontic (root canal) infections are generally considered to be caused by the invasion of microorganisms which destroy pulp tissue and extend to the periapical region. No definitive study has identified a specific bacterium or group of bacteria as etiological agents. We quantitively measured antibodies present in the serum of 30 normal individuals and patients with either chronic (n = 30) or acute (n = 30) periapical lesions with the indirect fluorescent antibody (IFA) and enzyme-linked immunosorbent assay (ELISA) for IgG and IgM against 11 oral microorganisms routinely isolated from such lesions. The results were analyzed statistically. Analysis of variance of …

Gingival Condition In Areas Of Minimal And Appreciable Widths Of Keratinized Gingiva, Myles C. Miyasato

Loma Linda University Electronic Theses, Dissertations & Projects

This investigation evaluated the gingival condition of areas with minimal (less than or equal to 1.0 millimeter) and appreciable (greater than or equal to 2.0 millimeters) widths of keratinized gingiva.

Sixteen dental, dental hygiene, and dental assisting students and dental faculty who had contralateral or unilateral areas of minimal and appreciable widths of keratinized gingiva on the mid-buccal surface of mandibular bicuspids were examined. Gingival exudate, plaque, gingival inflammation based on color change and/or swelling and bleeding on probing were evaluated. The results showed that all areas examined were plaque free. Three of 32 areas showed clinical gingival inflammation and …

The Lasting Antimicrobial Qualities Of Three Root Canal Sealing Materials : Grossman's Sealer, Rickert's Sealer, And N2 Permanent, Lee R. Ingersoll

Loma Linda University Electronic Theses, Dissertations & Projects

An in vitro study using polyethylene tubes filled with Grossman's sealer, Rickert's sealer, and N2 permanent was conducted over a six month period in an effort to determine their lasting antimicrobial properties against eight different microorganisms.

From the study it was observed that N2 permanent possesses a long-lasting antimicrobial effect, but this effect appears to diminish greatly with time. Further investigation is needed to determine whether or not the effect is actually permanent in nature. The N2 permanent was also shown to have broader antimicrobial effectiveness against the eight microorganisms tested. N2 permanent produced zones of inhibition against five of …