Dental Materials Commons^™

An Evaluation Of The Cytotoxicity Of Root Canal Filling Materials On Tissue Culture Cells In Vitro: Grossman's Sealer, N2 Permanent, Rickert's Sealer, And Cavit, Donald D. Antrim

Loma Linda University Electronic Theses, Dissertations & Projects

An in vitro study using radioactively-labeled tissue culture cells was conducted over a seven-month period on Grossman's sealer, Rickert's sealer, N₂ Permanent, and Cavit to determine the lasting and relative tissue toxicity of these materials.

From this study it was observed that all materials possess lasting tissue toxicity. When relative toxicity is considered, Grossman's is the most toxic, followed by N₂, Rickert's and Cavit in descending order of toxicity. Both Grossman's and N₂ would be considered highly toxic, with Rickert's displaying moderate toxicity. Cavit would be considered mild to moderate in toxicity.

The use of radioactively-labeled …

Heat Treatment Of Chrome Cobalt Alloy Orthodontic Wire, Galen M. Fillmore

Loma Linda University Electronic Theses, Dissertations & Projects

Chrome cobalt alloy orthodontic wire may be heat treated to increase spring performance and efficiency. This study was designed to quantify the effects that several heat treatment temperatures have upon the ability of .016" x .022" type 1 chrome cobalt wire to resist permanent deformation. In addition, the changes in resistance to permanent deformation due to heat treatment at 900° F were studied in .018" stainless steel wire and chrome cobalt wire of all four tempers.

When compared to untreated wire, .016" x .022" type 1 chrome cobalt wire exhibited a maximum increase of approximately 174 percent in resistance to …

Histological Comparison Of Human Pulpal Tissue Reactions After Vital Partial Pulpectomies Using N-2, Dycal And Zoe Paste, David P. Clark

Loma Linda University Electronic Theses, Dissertations & Projects

A histological comparison of forty-four human teeth in which vital partial pulpectomies were performed, and the pulp stumps covered with dycal, N-2 and ZOE was carried out. The time interval at which the teeth were extracted for study was ten, twelve and fourteen weeks. These teeth were on patients twelve through seventeen years of age and were to he extracted for orthodontic purposes. The teeth were caries free, vital and asymptomatic. The percent retaining vital tissue, time intervals and type of paste were as follows:

• 14 week, dycal 75%
• 14 week, N-2 100%
• 12 week, ZOE 30%
• 12 week, N-2 …

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 …

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.

The Theoretical Distribution Of Forces In The Rigid Component Of The Buccal Arch Positioner, Dennis H. Teruya

Loma Linda University Electronic Theses, Dissertations & Projects

The distribution of an applied force to the rigid component of the Buccal Arch Positioner was determined with a theoretically formulated model. The rigid component was assumed to be a free body without the semi-rigid attachments and was evaluated at four points for the force distribution. The summation of the forces and the moments were equated to zero and were utilized to derive equations to solve for the unknown forces. The unknown forces at each point of the rigid component were solved for in terms of the given force applications.

A laterally directed force application at one of the posterior …

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.

A Study Of The Evaluation Of Various Techniques And Materials In The Obturation Of Lateral And Accessory Canals, Allen E. Flans

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this investigation was to test the effect of different types of condensation, irrigants, filling materials and techniques, and variations in root canal preparation, on the success of sealing lateral and accessory canals, whose presence was determined before hand, and to relate certain inherent anatomic and morphologic characteristics of these canals to the amount of sealing obtained. Seventy-three teeth containing 85 lateral canals were instrumented and irrigated with either NaOCl, NaOCl-RC Prep or saline. The filling materials used were gutta percha, softened and unsoftened and Cavit. Half the teeth were filled using sealer. Final radiographs were studied for …

The Development Of A New Appliance For The Third Stage Of Begg Treatment, Ronald C. Parker

Loma Linda University Electronic Theses, Dissertations & Projects

The third stage of Begg treatment can pose difficulties to the orthodontist. Some of the undesirable developments encountered are anchorage loss, unintentional tooth tipping, extrusion, intrusion, palatal and mandibular rotation, muscular strain and profile deficiency or procumbency. In the interest of eliminating or minimizing these developments a new appliance was developed for use during the third stage of treatment.

Simply described, the appliance consisted of a rigid vestibular arch that provided anchorage for flexible extensions to each tooth. Extraoral force was directed to the maxillary rigid arch to counter anterior root torquing forces.

Anchorage control, maxillary incisor torquing efficiency and …

The Clinical Efficacy Of Cavit, Eric J. Herbranson

Loma Linda University Electronic Theses, Dissertations & Projects

This paper was undertaken to study the use of Cavit an[sic] an endodontic filling material.

Part I examines the physical and biological properties of Cavit. This material has a 14% linear setting expansion, which results in a very tight interphase seal. It is theorized that this type of seal in connection with a three dimensional obturation is necessary to prevent the flow of irritant from the oral environment to the periapical tissue.

The biological properties are tentatively shown to be similar to ZOE.

A description of the use of Cavit in various clinical situations is included.

Part II is a …

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 …

Endodontic Sealing Properties Of Cavit, Chloro-Rosin Gutta Percha, N2, And Silver Cones Using Radioisotopes, Frank H. Beal

Loma Linda University Electronic Theses, Dissertations & Projects

The main purpose of this investigation was to test the endodontic sealing abilities of silver cones, N2, warm gutta percha, chemically softened gutta percha, laterally condensed gutta percha and Cavit under carefully controlled conditions. Evaluations were done by radiographic, macroscopic, microscopic, and autoradiographic examinations.

The four points which must be considered when evaluating the efficacy of sealing root canal systems, in vivo, were presented and discussed.

Cavit as a total endodontic filling material was presented, investigated and discussed.

An improvement of the chloro-rosin - gutta percha diffusion technique was presented.

The concept of surface as well as marginal leakage was …

A Clinical Evaluation Of A Technique Utilizing Plastic Modules For Cuspid And Incisor Retraction, Dwane I. Johnston

Loma Linda University Electronic Theses, Dissertations & Projects

In a clinical study, polyurethane-type plastic modules were evaluated for use in retracting cuspids and incisors in Class I extraction cases.

Seven patients were selected to be treated with a technique utilizing these plastic modules. All cases were in Class I molar relationship and were either bimaxillary, protrusive or had tooth-size, arch-length discrepancies.

Evaluation was based on rate of cuspid and incisor retraction and the control of molar anchorage during the retraction phase.

At four-week intervals data were collected on space closure. At the same time, such subjective data as amount and duration of pain, difficulty of appliance adjustment and …

The Effectiveness Of Camphorated Paramonochlorophenol, Metacresyl Acetate, And Prednisolone In Combination As An Antimicrobial Agent, Maurice Cutler

Loma Linda University Electronic Theses, Dissertations & Projects

Post-treatment discomfort following endodontic procedures can be caused by inflammation due to injudicious use of intracanal medicaments. Camphorated paramonochlorophenol, metacresyl acetate, and prednisolone in combination is advocated to reduce the inflammatory potential of the germicide and thus reduce the occurrence of post-operative pain. It is imperative that a medicament retain antimicrobial activity while reducing inflammatory potential.

This investigation was undertaken toward determining on an in vitro quantitative bactericidal versus bacteriostatic basis by use of the broth dilution test tube method whether camphorated paramonochlorophenol, metacresyl acetate, and prednisolone in combination retains antimicrobial activity comparable to selected other commonly used nonspecific germicides. …

Correlation Of The Actual Position Of The Root Canal Filling In Human Teeth To Its Apparent Location On The Radiograph, Dominic J. Niccoli

Loma Linda University Electronic Theses, Dissertations & Projects

Human teeth mounted in individual plaster blocks were studied to determine the actual location of the root canal filling when it appears to be exactly at the radiographic apex. The original sample consisted of 109 teeth treated during endodontic technique class by junior dental students at Loma Linda University. In the most ideal manner possible, these teeth were radiographed on a flat surface with the x-ray tube perpendicular to the film and blocked tooth.

Five dentists examined the radiographs, and each one independently listed the canals he judged filled exactly to the radiographic apex. The investigator sorted out the choices …

Oral Bandage Tissue Reaction In Dogs, John Rozema

Loma Linda University Electronic Theses, Dissertations & Projects

This experiment was designed to evaluate an oral surgical dressing which may be used as an aid to healing tissue. The parameters of evaluation were directed toward wound healing enhancement, duration, and stability of the bandage. A histological evaluation of the surgical wounds protected with the bandage as compared to the control wounds was made.

The surgeries were performed on eight dogs in a double controlled experiment and were in the form of bilateral maxillary gingivectomies and mandibular molar tooth extractions. The surgery sites on the left were covered with the Orahesive Bandage while the right side remained exposed to …

Accuracy Of The Indirect Method Evaluated By Mercury Micromeasurement, Estol C. Pruett

Loma Linda University Electronic Theses, Dissertations & Projects

Although the indirect method for preparing dental castings has been in use for over forty-five years, very little information has appeared in dental literature relative to its accuracy. The development of a precise and quantitative method for determining the adaptation of wax patterns or castings was necessary before such an evaluation could be considered valid. It was felt the Mercury Micromeasurement test, devised in 1958 by Hollenback, should meet these requirements. A description of the test had been published. However, at the time the project was begun, no data had appeared in the literature.

In order to establish a standard …

An Evaluation Of The Physical Properties Of Cohesive Gold (Mat And Foil), Earl W. Collard

Loma Linda University Electronic Theses, Dissertations & Projects

Methods and instruments were devised particularly for this research project on the physical properties of cohesive gold, whereby the following procedures were accomplished:

1. Cohesive gold can be annealed under controlled conditions.
2. The blow delivered by an automatic spring mallet, pneumatic mallet, and Electro-Mallet can be evaluated and controlled.
3. The condensing point can be stepped in accurate and controlled increments.
4. Increments of laminated gold can be used permitting a known thickness of foil beneath the condensing point at all times.
5. A standard analytical balance can easily be converted for specific gravity tests.
6. Specimens were tested for adaptation by air pressure while …