Periodontics and Periodontology Commons^™

Periodontal Repair In Dogs : Effect Of Recombinant Human Transforming Growth Factor Beta-1 On Guided Tissue Regeneration, Saghi Shayan Razi

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this study was to evaluate bone and cementum regeneration in the critical size, supraalveolar, periodontal defect model following surgical implantation of recombinant human transforming growth factor beta-1 (rhTGFß-1) in conjunction with guided tissue regeneration (GTR). Five male beagle dogs were used in a split-mouth design. Alternate jaw quadrants in consecutive animals received GTR with rhTGFß-1 in a resorbable calcium carbonate carrier. Contralateral jaw quadrants received GTR with carrier only (control). The healing interval was 4 weeks. Clinical healing was generally uneventful, however, minor membrane exposures were observed for both treatments with limited gingival inflammation. All defects with …

Bone Morphogenetic Proteins And Periodontal Repair, Michael B. Lee

Loma Linda University Electronic Theses, Dissertations & Projects

For over thirty years now, research has been carried out to isolate and purify bone morphogenetic protein (BMP), a substance which has been shown to induce heterotopic bone formation in various animal species. Recent advances in the fields of developmental biology, molecular biology and genetics, have shown that the BMPs not only are responsible for postfetal bone induction (including normal bone remodeling, healing and repair), but are also critical during embryogenesis - not only in regards to the skeletal system, but quite possibly in the morphogenesis and pattern formation of other tissues and organs as well.

Due to their bone …

Alveolar Bone And Cementum Regeneration Following Periodontal Reconstructive Therapy : A Review Of Histologic Observations In Man And Experimental Animals, Karen E. Rodden

Loma Linda University Electronic Theses, Dissertations & Projects

Periodontal regeneration includes the formation of both alveolar bone and cementum. Studies reporting histologic evidence of healing following periodontal reconstructive therapy were reviewed to determine whether regeneration of these structures improves with increasing healing interval, and whether they regenerate independently or whether regeneration of one structure is dependent upon regeneration of the other. Additionally, the review addresses whether specific reconstructive modalities predictably yield increased amounts of regeneration. Differences in regenerative potential between humans, nonhuman primates, and canines were also examined. Results of over a decade of studies of periodontal reconstructive therapy were tabulated by family (human, nonhuman primate, and canine) …

Periodontal Repair In Dogs : Evaluation Of Rhbmp-2 Carriers, Lauralee Nygaard

Loma Linda University Electronic Theses, Dissertations & Projects

This study evaluated candidate carriers for recombinant human bone morphogenic protein-2 (rhBMP-2) in periodontal reconstructive surgery.

Canine demineralized bone matrix (DBM), bovine inorganic crystallene bone matrix (Bio-Oss), bovine derived microfibrillar collagen matrix (Helistat), poly (D,L-lactide-coglycolide) micropaiticles (PLGA), and polylactic acid granules (Drilac) were used with rhBMP-2 (20 (µg/100 µl implant volume) in routine critical size canine supraalveolar periodontal defects. Contralateral defects in six beagle dogs were randomly assigned to receive: DBM/rhBMP-2, DBM-control, Bio-Oss/rhBMP-2, Helistat/rhBMP-2, PLGA/rhBMP-2, or Drilac/rhBMP-2, all with autologous blood except for Helistat and PLGA. Animals were sacrificed eight weeks post-surgery and block sections of the defects were processed …

Experimental Peri-Implant Tissue Breakdown In Rhesus Monkeys, Oliver Hanisch

Loma Linda University Electronic Theses, Dissertations & Projects

The aim of this investigation was to characterize peri-implant tissue breakdown following ligature-induced plaque accumulation around osseointegrated implants in the rhesus monkey. Two hydroxyapatite-coated cylindrical implants were inserted bilaterally in the second premolar and first molar region of both mandible and maxilla in four non-human primates (Macaca mulatto). The implants were left submerged to osseointegrate for one year. Eight weeks after healing abutment connection, a two-month plaque control program was initiated. At the end of this period, clinical and radiographic recordings were carried out, and peri-implant subgingival microbial samples were obtained (baseline). Subsequently, cotton ligatures were placed around …

Periodontal Repair In Dogs : Part I : Evaluation Of The Natural Disease Model ; Part Ii : Eptfe Barrier Membranes Support Wound Stabilization And Enhance Bone Regeneration, James Marc Haney

Loma Linda University Electronic Theses, Dissertations & Projects

Animal models are frequently consulted for histometric analysis of reconstructive periodontal therapy. Statistical analysis of induced lesion defects and surgically created defects from our laboratory suggest defect size homogeneity is critical for the model to discriminate treatment effects. This study characterizes natural disease defects in beagle dogs. Buccal-lingual histologic sections from the 2nd, 3rd, and 4th mandibular premolar teeth (P2, P3, P4) from 6 aged beagle dogs with natural disease defects were evaluated for variation in defect height between pair matched tooth types, and jaw quadrants, as well as estimated confidence intervals for treatment differences between left and right pair …

Transforming Growth Factor-Beta 1 Expression In Developing Ovine Teeth As Visualized By In Situ Hybridization, Søren Jepsen

Loma Linda University Electronic Theses, Dissertations & Projects

Recently we demonstrated that human dentin contained relatively high amounts of transforming growth factor beta (TGF-ß) and proposed that dentin TGF-ß originated from odontoblasts. Because of the suggested role of TGF-ß in mediating cellular interactions in dental cell development by paracrine mechanisms, we studied the expression of TGF-ß message in developing teeth by in situ hybridization. 5 µm serial sections of neonatal sheep mandibular third molars that had been fixed in glutaraldehyde and paraffin-embedded were used for in situ analysis. An [³⁵S]-labeled cRNA probe, complementary to TGF-ß1 mRNA, was constructed from human TGF-ß1 cDNA. Northern analysis of total …

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. …

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 …

The Effect Of Post-Operative Use Of Chlorhexidine On Periodontal Regeneration In Monkeys With Chronic Bifurcation Defects, J. Pat Bishop

Loma Linda University Electronic Theses, Dissertations & Projects

Periodontal regeneration and inflammation was evaluated histometrically in 36 paired teeth in six macque(sic) monkeys with chronic bifurcation defects. Daily topical TL Chlorhexidine was applied to one-half of the teeth, saline to the other half for six weeks after the bifurcation defects were surgically debrided. Measurements were made from a section taken from the mid-bifurcation for each tooth. The results demonstrated no significant difference in the area of inflammatory response or the degree of regenerative capacity of post-operative healing between Chlorhexidine treated and paired nontreated control teeth.

Effect Of Post-Operative Use Of Chlorhexidine On Regeneration Of Bifurcation Defects In Dogs, Gary Bogle

Loma Linda University Electronic Theses, Dissertations & Projects

The daily post-operative use of topical chlorhexidine application has been compared to daily toothbrushing. Periodontal defects were experimentally created in the bifurcations of lower premolars in dogs. The defects were treated by surgical debridement. Chlorhexidine application and toothbrushing were performed post-operatively for six weeks on contralateral pairs of teeth. The amounts of connective tissue and bone regeneration were evaluated from microscopic sections of the bifurcation areas. No difference between chlorhexidine and tooth brushing was found for the connective tissue attachment. However, significantly more bone had regenerated in the chlorhexidine treated areas than the tooth brushed area.

Microscopic Evaluation Of Topically Applied Chlorhexidine Gluconate On Gingival Wound Healing In Dogs, Robert C. Hirst

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate microscopically the effect of topically applied 2% chlorhexidine gluconate on the healing of gingival wounds in dogs.

One week after the teeth were scaled and polished, seven experimental wound sites were prepared in the facial gingiva adjacent to the four premolars on each side of the maxillary arch in six young Labrador dogs. From this point the dogs were fed a soft plaque-inducing diet. Chlorhexidine solution was applied daily to either the right or left maxillary premolars while on the opposite side of the arch in three dogs the first and second …

Marrow Isografts In The Oral Cavity Of Mice, Robert L. Merin

Loma Linda University Electronic Theses, Dissertations & Projects

The objectives of this study were to develop an animal model for testing oral bone and marrow transplantation that is adaptable to immunological studies; to determine the effect of an isogeneic graft of cancellous bone and marrow on the healing of surgically created defects; and to determine the fate of grafted isogeneic cancellous bone and marrow transplanted into defects. Fourteen CBA/H mice served as experimental animals and bilateral intraoral defects were prepared. The experimental side received isogeneic graft material while the other side served as a control. Osseous healing was found to be accelerated in the defects receiving graft material …

The Effect Of Oral Allografts Of Cancellous Bone And Marrow In Mice, George E. Deeb

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was: to develop a model for testing oral bone transplantation; to study the healing of a surgically produced defect with and without the transplantation of strongly allogeneic cancellous bones and marrow; and to determine the fate of the allogenic grafts. Twenty-eight CBA/H mice served as experimental animals. Intra-oral defects were made and in 14 of the animals strongly allogenic cancellous bone and marrow were transplanted. The 14 remaining animals served as controls. It was observed that the healing was delayed in the experimental animals as compared to the controls and that the grafted material was …

Root Exposure And Its Effect On The Fluid Movement Within The Tooth, William J. Busch

Loma Linda University Electronic Theses, Dissertations & Projects

This study examined the fluid movement in dentin associated with the exposure of the root surface for varying periods of time ranging from 75 minutes to 30 days. Eight kittens received experimental defects on the roots of the canines. Just prior to sacrifice a fluorescing dye was injected intraperitoneally to make the fluid within the dentin visible under ultraviolet light. Frozen ground sections were prepared and examined. The results showed that the exposed side of the root had a reduced amount of fluid fluorescence when compared to the opposite side of the tooth which had an intact root surface. The …

The Effect Of Elevated Glucose On Neutrophilic Phagocytosis In Genetically Diabetic Mice, Larry B. Thompson

Loma Linda University Electronic Theses, Dissertations & Projects

Infiltration to an injury site or area of bacterial contamination by polymorphonuclear leucocytes (or neutrophils) is an early and essential phase of the early inflammatory reaction. Their action on foreign matter is the most critical step taken by body defense mechanisms in the first 24 hours. Anything which interferes with that action, phagocytosis, greatly hampers early inflammation. This study was designed to see the effect of elevated glucose levels on neutrophil phagocytosis in a unique strain of genetically diabetic mice.

Twenty-two diabetic and twenty-four control female mice were used. Blood glucose determinations and total white counts were made on each …

Histopathological Variations Of Periapical Granulomas And Radicular Cysts, Thanapen Kanchanasut

Loma Linda University Electronic Theses, Dissertations & Projects

The periapical dental granuloma and cyst is the most frequent sequela of pulpitis. These lesions are always intraosseous and often become quiescent after the acute phases are over, forming a space which primarily consists of chronic inflammatory tissue. This chronic inflammatory tissue usually appears as a one-centimeter area of punched out bone on the x-ray film and is referred to as a dental granuloma. Should epithelium choose to proliferate in this inflammatory area, it may undergo subsequent cystic degeneration forming the typical periapical cyst. While much has been written with regard to the etiology and treatment of the apical cyst …

The Response Of Gingival Tissues To Alterations In Ph, Robert C. Jann

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the histopathological and clinical changes that occurred when a continuous supply of exogenous acid or base, at varying pH, was delivered adjacent to the gingival crest of the monkey. A related goal was to develop a monkey model system which would deliver test solutions continuously and atraumatically, to the experimental gingival sites.

Two young adult female monkeys had a perfusion apparatus attached to certain maxillary teeth so that test solutions were deposited atraumatically to the marginal gingival tissues. During the experimental periods the animals were kept in primate restraining chairs and fed …

An In Vivo Perfusion Apparatus For Studies On Gingival Disease In The Albino Rat : Assessment By A Perfusion Of The Enzymes Collagenase And Hyaluronidase, James A. Smith

Loma Linda University Electronic Theses, Dissertations & Projects

This thesis describes an in vivo perfusion apparatus which can continuously deliver controlled quantities of solutions to localized, contralateral intraoral areas in albino rats. Three animals were per fused on the experimental area (the mesial sulcular area of the maxillary first molar) on one side with tap water and Trypan blue. Localization of the solution delivered and minimal histological changes due to the presence of the apparatus was demonstrated on these animals. Solutions of .5%, 1%, and 2% hyaluronidase and collagenase were perfused on the experimental areas of nine animals. When both enzymes were used, hyaluronidase always preceded collagenase in …

A Study Of Alveolar Bone Loss And Two-Hour Postprandial Blood Sugar Levels, R. Leslie Arnett

Loma Linda University Electronic Theses, Dissertations & Projects

Two-hour postprandial blood sugar determinations were carried out on 500 patients referred for periodontal care. The mean percentage of alveolar bone loss around the mandibular bicuspid teeth was established for each individual. The subjects were then grouped according to blood sugar levels and the mean alveolar bone loss was calculated. The group was separated into male and female sub-groups and data was computed for these segments as well as the total sample. The data was evaluated in a similar manner for those subjects between 40 and 49 years of age.

No Chi-square determinations were statistically significant but significance in differences …

The Effect Of Glucose On Neutrophilic Phagocytosis, Donald F. Adams

Loma Linda University Electronic Theses, Dissertations & Projects

Samples of blood were obtained from thirty healthy young adult males (Loma Linda University School of Dentistry), and contaminated with bacteria. Varying concentrations of pure glucose were added to this mixture to observe the effect of the glucose on in vitro neutrophilic phagocytosis. As the glucose levels increased a statistically significant suppression was noted in the ability of the neutrophilic leukocytes to engulf Staphylococcus epidermidis.

It was not possible, however, to predict the degree of suppression for any particular level of glucose added nor is it possible to state that suppression will occur in any one individual.

Two methods of …