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Articles 301 - 330 of 369

Full-Text Articles in Dentistry

Concentration Of Leukotrienes B4 And C4 In Human Periradicular Lesions, Elisabetta Cotti Dec 1990

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 …


The Effect Of An Anti-Osteoclastic Agent And A Collagen Sponge On Root Resorption Following Regenerative Periodontal Surgery In The Dog, Rudolf Hahn Aug 1989

The Effect Of An Anti-Osteoclastic Agent And A Collagen Sponge On Root Resorption Following Regenerative Periodontal Surgery In The Dog, Rudolf Hahn

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies indicate that root resorption is a frequent sequela to significant amounts of periodontal repair following experimental regenerative periodontal surgical procedures in animal models. To study if root resorption can be reduced or prevented, periodontal repair was evaluated in large horizontal circumferential defects in the dog in the absence of influence from the oral environment. Diphosphonate (Cl2 MDP) applied topically to the root surfaces prior to wound closure as well as the use of a collagen sponge membrane (Helistat®) draped over the root surfaces and a control with no additional treatment after defect creation were the modalities employed. …


Immunologic Mechanisms Involved With Human Endodontic Lesions, Sunita V. Prabhu Jun 1988

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 …


Electromagnetic Field Variations In The Activation Of Bone Cell Synthesis, Gary Ketcherside Apr 1988

Electromagnetic Field Variations In The Activation Of Bone Cell Synthesis, Gary Ketcherside

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]


A Non-Human Primate Model For Studying Corticotomy-Facilitated Orthodontic Tooth Movement, R. David Rynearson Jun 1987

A Non-Human Primate Model For Studying Corticotomy-Facilitated Orthodontic Tooth Movement, R. David Rynearson

Loma Linda University Electronic Theses, Dissertations & Projects

This study was undertaken to test the hypothesis that a corticotomised tooth moves as a tooth-bone unit when under orthodontic force. A non-human primate model was designed to test the hypothesis. The non-human primate selected was Macaca fasicularis. Three adult males with erupted third molars were chosen so that extrapolation could be made to the adult human. The methods employed included the following: 1) Each animal had one treatment quadrant and one control quadrant per arch; 2) Pre-op and post-op study models were made; 3) All 2nd premolars, 2nd molars, and 3rd molars were banded; 4) A full-thickness flap …


The Determination Of Antibody Levels In Endodontic Patients Against Eleven Microorganisms Using Ifa And Elisa Techniques, William C. Payne Jun 1987

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 …


Histologic Host Response To Polyoxymethylene Prosthesis As A Temporomandibular Joint Condylar Replacement, Frederick R. Mathews May 1987

Histologic Host Response To Polyoxymethylene Prosthesis As A Temporomandibular Joint Condylar Replacement, Frederick R. Mathews

Loma Linda University Electronic Theses, Dissertations & Projects

Polyoxyinethylene (Delrin) is a polyacetyl homopolymer which has been used successfully in many orthopedic joint replacements. To determine histologic host response to Delrin as a temporomandibular joint condylar replacement condyles were removed from ten fully mature macaca fasicularis monkeys. The condyles were replaced with a total prosthetic Delrin condyle attached to a titanium mesh. Specimens obtained at one, two, and six months indicated total acceptance of the Delrin, remodeling of the glenoid fossa and formation of bone between the middle cranial fossa and the roof of the glenoid fossa. These findings would indicate Delrin is a viable option for condylar …


The Effects Of Certain Oral Bacteria On The In Vitro Growth Of Bacteroides Gingivalis, Steven G. Morrow Sep 1986

The Effects Of Certain Oral Bacteria On The In Vitro Growth Of Bacteroides Gingivalis, Steven G. Morrow

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of nine gram positive and grain negative cocci and bacilli, which are indigenous to the oral cavity, on the in vitro growth of Bacteroides gingivalis was examined in this study. A pure culture of B. gingivalis is was obtained from the American Type Culture Collection. The nine oral test organisms were Streptococcus mitis, Streptococcus mutans, Streptococcus faecalis, Staphylococcus epidermidis, Staphylococcus aureus, Corynebacteriurn hofmanii, Lactobacillus acidophilus, Branhamella catarrhalis, and Escherichia coli. The effect on the growth of B. gingivalis of the nine test organisms was evaluated on a solid medium by use of …


The Use Of Dura Mater As A Meniscus Replacement In Tmj Surgery, Kim J. Dipasquale Aug 1986

The Use Of Dura Mater As A Meniscus Replacement In Tmj Surgery, Kim J. Dipasquale

Loma Linda University Electronic Theses, Dissertations & Projects

Internal derangement of the temporomandibular joint is recognized as a problem of significant magnitude in both medical and dental circles. The last decade has seen a steady progression in the knowledge and sophistication of not only the anatomy and physiology of the temporomandibular joint, but also in the techniques of non-surgical and surgical management of internal derangements. Surgical correction of the unrepairable disc has typically been addressed by performing a menisectomy followed by placement of a non-physiologic implant material.

The animal study reported here was performed in order to evaluate the histologic fate and biological compatibility of freeze-dried dura when …


Effects Of Lateral Mandibular Expansion On Mandibular Morphology In The Growing Rat : A Comparative Study Of Treatment Effects With Orthopaedic And/Or Surgical Procedures, Eric Looi Jun 1986

Effects Of Lateral Mandibular Expansion On Mandibular Morphology In The Growing Rat : A Comparative Study Of Treatment Effects With Orthopaedic And/Or Surgical Procedures, Eric Looi

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to investigate the effects of mandibular expansion by orthopaedic and surgical procedures in the growing rat mandible.

Sixty-four 35 day old Sprague Dawley Harlan rats were divided into four groups of 16 rats each and categorized as the control, orthopaedic expansion, surgery without graft and surgery with graft respectively. Prefabricated appliances were used for orthopaedic expansion of the mandibles and maintaining surgical expansion at the symphysis in the respective groups. Oxytetracycline were given intraperitoneally to mark areas of bone remodeling. Half the number of rats from each group were sacrificed at the end of …


Stability In Mechanical Expansion Of The Maxilla With Surgical/Mechanical Expansion Of The Mandible In An Adult Baboon, Robert D. Mitchell Jun 1985

Stability In Mechanical Expansion Of The Maxilla With Surgical/Mechanical Expansion Of The Mandible In An Adult Baboon, Robert D. Mitchell

Loma Linda University Electronic Theses, Dissertations & Projects

Expansion of the maxilla at the midpalatal suture has had much investigation and is a recognized option in orthodontic therapy. Lateral expansions of the mandible through surgical separation at the symphysis have been done in animal studies. A combination of these procedures has not yet been done together.

The purpose of this study was to expand both the maxilla and the mandible of a baboon simultaneously while maintaining occlusion. The amount of expansion and stability was studied using photographs, models, cephalograms, and tetracycline bone labels using U.V. microscopy.

A young adult baboon with full dentition and normal occlusion was used. …


Observation Of Bone Formation In The Mandibular Symphysis Following Surgical Separation And Slow Mechanical Expansion In A Baboon, Robert J. Homer Jun 1982

Observation Of Bone Formation In The Mandibular Symphysis Following Surgical Separation And Slow Mechanical Expansion In A Baboon, Robert J. Homer

Loma Linda University Electronic Theses, Dissertations & Projects

Mechanical expansion of the maxilla, at the midline suture, is a widely accepted orthodontic procedure used to gain arch width in certain types of maxillary deficient arches.

In animal research on the mandible, techniques using surgical separation at the symphysis with immediate expansion up to 12 mm, fixation with a metal splint, and autogenous bone transplanted into the expanded area, have been reported to be successful.

To date, no experiment utilizing slow mechanical expansion of the mandible at the symphysis has been reported.

In this pilot study, the mandible of a female baboon was surgically separated A-P at the symphysis. …


The Effects Of Orthodontic Repositioning Into A Surgically Expanded Site On Bone Formation And Tooth Mobility In A Baboon, Anthony B. Lier Aug 1981

The Effects Of Orthodontic Repositioning Into A Surgically Expanded Site On Bone Formation And Tooth Mobility In A Baboon, Anthony B. Lier

Loma Linda University Electronic Theses, Dissertations & Projects

For sometime, expansion of the maxillary arch, by means of surgical and mechanical procedures, have been acknowledged with minimal attention directed toward the mandible. In this pilot study a surgical technique was employed in separating the mandible, A-P, at the symphysis. The interosseous void, approximately 10 mm., was then filled with autogenous bone marrow collected from the greater trochanter and the crest of the ilium.

The surgical site was then maintained for a period of eight (8) weeks with the aid of a precast chromium-cobalt splint and titanium mesh placed intradentally and at the symphysis, respectively. Following the stabilization period …


The Effect Of Folic Acid Supplementation On Gingival Healing After Oral Hygiene Therapy, Marilyn J. Wankier Apr 1981

The Effect Of Folic Acid Supplementation On Gingival Healing After Oral Hygiene Therapy, Marilyn J. Wankier

Loma Linda University Electronic Theses, Dissertations & Projects

To determine the effect of folic acid supplementation on gingival healing after oral hygiene therapy, eight teeth (#3, 4, 5, 6, 11, 12, 13, 14) of sixteen human subjects with moderate levels of gingival irritation were studied. Clinical parameters included measurement of gingival fluid, pocket depth, bleeding upon probing, and plaque. Serum and red blood cell folic acid levels were determined using radioimmunoassay (RIA). Based on clinical parameters and serum folate levels, two similarly matched groups were established. The teeth were scaled and polished. Brushing and flossing instructions were given.

After one week of oral hygiene therapy alone, the experimental …


The Effect Of Periapical Inflammation On Cellular Cementum : A Scanning Electron Microscope Study, Gary S. Yonemoto Jun 1980

The Effect Of Periapical Inflammation On Cellular Cementum : A Scanning Electron Microscope Study, Gary S. Yonemoto

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to obtain information on the morphologic changes that occur in cellular cementum exposed to periapical inflammation.

Ten single rooted human teeth were collected. There were five specimens of normal cellular cementum and five specimens of diseased cellular cementum, which had been exposed to periapical inflammation. Each specimen was fractured longitudinally through the apical foramen, leaving the organic component intact. The cross-sectional morphology of cellular cementum was then examined using an ARM Model 1000 scanning electron microscope. Energy dispersive x-ray spectrometry was also conducted on samples representative of the two test groups.

A methodology was …


Orthognathic Surgical Expansion Procedure Of The Mandible Of Female Baboon Papio Sp?, Willis L. Schlenker Jun 1980

Orthognathic Surgical Expansion Procedure Of The Mandible Of Female Baboon Papio Sp?, Willis L. Schlenker

Loma Linda University Electronic Theses, Dissertations & Projects

Expansion of the maxillae is a well recognized procedure in orthodontics. Little is known about Mandibular Expansion. This project is a pure research of the possibility of expanding the mandible laterally at the symphysis on a baboon.

The symphysis was cut A-P and expanded laterally 11 mm, then held and stabilized with a titanium mesh work screwed to the inferior border of the mandible. The defect area was filled with a bone graft of marrow and cancellous bone fragments taken from the greater trochanter and the crest of the ilium. New bone did fill in the defect and the expansion …


An Ultra-Violet Light Microscopic Study Of The Hydroxylapatite Ceramic-Bone Interface Phenomena, Leonard W. Pierce Jun 1980

An Ultra-Violet Light Microscopic Study Of The Hydroxylapatite Ceramic-Bone Interface Phenomena, Leonard W. Pierce

Loma Linda University Electronic Theses, Dissertations & Projects

Preparations used in this study were obtained from an investigation which had undertaken the following:

Durapatite, a hydroxylapatite ceramic was implanted in 24 mature Beagle dogs to study its maintenance effect on the alveolar bone of the mandible.

After dividing the dogs into two groups, a fresh socket and a healed socket group, the posterior teeth were removed and alveolectomies were performed. Eight ceramic implants were then placed in the right mandible of each animal in each group. The healed group received the implants five weeks after tooth removal and the fresh socket group received implants immediately after extraction.

The …


The Effect Of Escherichia Coli Endotoxin On The Cat Periapical Tissues, Thomas G. Dwyer Jun 1979

The Effect Of Escherichia Coli Endotoxin On The Cat Periapical Tissues, Thomas G. Dwyer

Loma Linda University Electronic Theses, Dissertations & Projects

The periapical tissue reaction to three concentrations of endotoxin solutions and to a sterile saline control solution was examined in six adult cats. The maxillary and mandibular cuspids were isolated and the pulps extirpated with barbed broaches. The four solutions (1, 10, 100 μg/ml endotoxin, and saline) were then injected into the four prepared teeth for each cat and the access cavities sealed with IRM.

At two week intervals, two cats were sacrificed and the specimens removed, while the remaining animals were retreated as previously described. The block tissue sections were radiographed, fixed in 10% buffered formalin, and prepared for …


Ultrastructural Study Of Wound Healing On A Root Planed And Citric Acid Treated Root Surface, Craig Martin Ririe Sep 1978

Ultrastructural Study Of Wound Healing On A Root Planed And Citric Acid Treated Root Surface, Craig Martin Ririe

Loma Linda University Electronic Theses, Dissertations & Projects

It has been shown previously that a root surface which has been scaled, root planed and demineralized by topical application of citric acid in vitro, is dominated by exposed collagen fibrils. The purpose of this study was to examine the mechanism of healing and possible reattachment of soft periodontal connective tissue to the root planed and subsequently acid treated root surfaces and to determine whether new collagen fibrils produced in the connective tissue could attach to these exposed fibrils.

Full thickness tissue flaps were raised and the coronal 4-5 mm of the labial alveolar plate removed over the maxillary incisor …


Isolation And Chemico-Physiologic Characterization Of A Parotid Hormone Activity From Porcine Glands, Jean-Marc Tieche Sep 1978

Isolation And Chemico-Physiologic Characterization Of A Parotid Hormone Activity From Porcine Glands, Jean-Marc Tieche

Loma Linda University Electronic Theses, Dissertations & Projects

For the past decade, evidence has accumulated which suggests that the resistance of the teeth to dental decay is in part under systemic control. It was shown that the resistance is accomplished through the optimal operation of a dentinal fluid transport mechanism which is believed to be hormonally controlled by the hypothalamic-parotid gland endocrine axis. Although circumstantial evidence for such an endocrine function was strong, the isolation of a parotid hormone which stimulates the dentinal fluid transport mechanism remained to be accomplished.

Using modern biochemical techniques, a methodology was designed to isolate and purify the hormone from porcine parotid glands. …


Comparison Of Root Surfaces In Endodontic Lesions, Periodontic Lesions And Normal Human Teeth, Robert W. Hanson Jun 1978

Comparison Of Root Surfaces In Endodontic Lesions, Periodontic Lesions And Normal Human Teeth, Robert W. Hanson

Loma Linda University Electronic Theses, Dissertations & Projects

The healing potential of an endodontic lesion is usually greater than a periodontic lesion (Simon et al. 1972; Hiatt 1977). Periodontal regeneration places particular emphasis on the soft tissue-tooth interface (Stahl 1977). This interface was examined in fifteen extracted human teeth.

The teeth were divided into three groups: (1) periapical lesions, (2) periodontal lesions, and (3) healthy periodontal tissue. Criteria were established for each group. Freshly extracted human teeth meeting the criteria were fixed in gluteraldehyde or paraformaldehyde. The teeth were then selected for surface observation or cracked for cross sectional examination. The teeth were post fixed, dehydrated, and coated …


The Effects Of Inducing Functional Class Iii Malocclusion On Actively Growing Rat Mandibles, Aarin Chu Jul 1977

The Effects Of Inducing Functional Class Iii Malocclusion On Actively Growing Rat Mandibles, Aarin Chu

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]


Ultrasonic Versus Hand Filing Of The Human Root Canal System, Howard W. Scholz Jr. Jun 1977

Ultrasonic Versus Hand Filing Of The Human Root Canal System, Howard W. Scholz Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

A comparison was made of ultrasonic filing versus hand filing using three solutions to flood the canals of 24 extracted human maxillary central incisors. A modified PR-30 Cavitron insert was used in a Cavitron 1010 unit for the ultrasonic filing. The clinical crown was removed with a diamond saw and water spray at the cemento-enamel junction. The two major groups were ultrasonic filing versus hand filing; the three subgroups were solution/solvents - 10% EDTA, 2.0% NaOCl, and distilled water.

After filing, the roots were grooved longitudinally with a high speed bur and cracked opened with a mallet and chisel. The …


The Effect Of Endodontic Therapy On The Incidence Of Radiation Caries In Dogs, James A. Abbott Jun 1977

The Effect Of Endodontic Therapy On The Incidence Of Radiation Caries In Dogs, James A. Abbott

Loma Linda University Electronic Theses, Dissertations & Projects

Endodontic therapy was evaluated as a possible control or prevention modality of radiation type dental caries in dogs. Two adult male dogs with permanent dentitions had endodontic therapy performed on alternating teeth in each jaw. The nontreated teeth served as controls.

The dogs were irradiated with 7000 rad Cobalt-60 radiation fractionated over an eight week period. The dogs were killed at 60 and 182 days post-irradiation. The teeth were removed from the jaws and immersed in methylene blue dye, sectioned, and the dye penetration pattern photographed. Diffusion of the dye into the tooth structure was quantified and statistically analyzed.

A …


Apical Closure Induction Using Bone Growth Factors And Mineral Trioxide Aggregate, Kenneth W. Tittle Mar 1977

Apical Closure Induction Using Bone Growth Factors And Mineral Trioxide Aggregate, Kenneth W. Tittle

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared the ability of three different bone growth factor combinations with that of Ca(OH)2 to stimulate apical closure as well as the effectiveness of Mineral Trioxide Aggregate (MTA) as an apical barrier. Fifty-six roots of second and fourth mandibular premolars of seven six- month old beagle dogs were used. Periradicular lesions were created over a four week period. The canals were cleaned and shaped and filled with Ca(OH)2 for one week. They were then irrigated and received one of seven different treatments in a balanced design. Growth factors were placed in a carboxymethylcellulose carrier and delivered …


Histology Of Apical Tissue : A Comparative Study Of Sargenti Formula, Short Vs. Overfill, James G. Schulze May 1976

Histology Of Apical Tissue : A Comparative Study Of Sargenti Formula, Short Vs. Overfill, James G. Schulze

Loma Linda University Electronic Theses, Dissertations & Projects

Four Stump-tail monkeys (Macaca spiciosa) were used for this study to analyze, on a cellular level, the apical tissue of teeth overfilled versus teeth filled short 1-3 mm. of the radiographic apex with the Sargenti formula. In each animal four incisors were filled short and four incisors were overfilled. A final sample size consisted of 28 teeth. The time periods ranged from 48 hours to 120 days. After analysis of the histology it can be stated that the teeth filled short showed no inflammation to moderate inflammation in the periapical tissues. In teeth overfilled there was a range from moderate …


Determination Of Lead Content In Apical Tissue Following Root Canal Obturation With Sargenti's Formula, G. Merle Hickok May 1976

Determination Of Lead Content In Apical Tissue Following Root Canal Obturation With Sargenti's Formula, G. Merle Hickok

Loma Linda University Electronic Theses, Dissertations & Projects

Four Stump-tail monkeys were used to help determine if the lead in Sargenti's formula diffuses out into the apical tissue while confined entirely within the root canal. In each animal two teeth were filled with Sargenti's formula 1-2 millimeters short of the radiographic apex, and two teeth were filled with gutta percha and Proco-Sol sealer for controls, making a total sample size of sixteen. The time ranged from 48 hours to 120 days. Lead analysis using the spectrophotometric method showed a higher lead content in the teeth filled with Sargenti's formula than with the gutta percha controls.


Bone Regeneration Over Submerged Dental Roots In Dogs, Roger Lee Plata Jun 1974

Bone Regeneration Over Submerged Dental Roots In Dogs, Roger Lee Plata

Loma Linda University Electronic Theses, Dissertations & Projects

Nonendodontically treated roots were submerged 1.5 to 2.0 mm. below the alveolar crest in three dogs. Twelve roots were treated in this manner. Regeneration of alveolar bone can be seen in three weeks with complete bone coverage in five weeks. A complete lamina dura can be seen around the amputated roots.

Bone failed to regenerate over two of the twelve roots. In one case there was delayed healing due to the early loss of some sutures. A sinus tract developed connecting the oral environment with the contents of the pulp. This led to bone resorption and a necrotic pulp. In …


Histologic Comparison Of Apical Tissue Response To Endodontic Overfills With Gutta Percha And Grossman's Sealer Vs. Sargenti Method (N₂), Donald L. Brewer May 1974

Histologic Comparison Of Apical Tissue Response To Endodontic Overfills With Gutta Percha And Grossman's Sealer Vs. Sargenti Method (N₂), Donald L. Brewer

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared endodontic overfills of N2 and gutta percha-Grossman's Sealer from a histopathological basis. The study employed four male rhesus monkeys and a sample of 31 teeth.

The most obvious difference between the samples filled with N2 and the gutta percha-Grossman's Sealer samples was the recurring presence of ankylosis in the N2-treated teeth. Results also included bone necrosis, inflammation and root and bone resorption.

The N2 samples were considered to have evidenced greater violence of reaction apically.


A Method Of Analyzing Mandibular Movement, Richard B. Mccoy Jun 1973

A Method Of Analyzing Mandibular Movement, Richard B. Mccoy

Loma Linda University Electronic Theses, Dissertations & Projects

Mandibular movement is considered to be a fundamental factor in the study, analysis, and treatment of occlusion. For many years, dentists have realized that dental health depends upon the compatibility of mandibular movements and occlusion. This realization has led to the development of new methods and techniques for recording accurately and scientifically the movements of the mandible. In order for this data to be of scientific value, it must be stored in a usable form which is easily available for analysis.

The purpose of this research project was to develop a procedure for storing and recalling mandibular-movement information. Before such …