Dentistry Commons^™

Interobserver Reliability In The Diagnosis Of Pulpal And Periradicular Disease, Todd Peter Mellin

Theses and Dissertations

The purpose of this study was evaluate the interobserver reliability of endodontists in the diagnosis the presence or absence of pulpal and/or periradicular disease. The study used 47 patients presenting to the VCU School of Dentistry for screening appointments as a test population under the rules and regulations of the VCU IRB. The patients were examined separately by two endodontists, using a thorough patient history, clinical exam, and radiographs. The answer to the question was then answered, does the patient have pulpal and/or periradicular disease, and compared. The data was analyzed using Kappa and the standard error was determined to …

Prevalence Of Pulpal And/Or Periradicular Disease In The Vcu School Of Dentistry Screening Patient Population, Ellen Rives Oertel

Theses and Dissertations

The purpose of this study was to determine the prevalence and demographic predictors of pulpal and/or periradicular disease in an urban population. A total of 210 subjects were recruited from a population of patients that were screened for acceptance to the dental school clinics. The diagnosis of pulpal and/or periradicular disease was made using the following data: radiographic interpretation, patient's history of previous pain and chief complaint, and objective pulpal testing. Objective pulpal testing included percussion, palpation, electric pulp test, and cold. The unit of observation was the individual, not the tooth. The overall prevalence of endodontic disease among the …

The Effect Of Naocl, Ca(Oh)2, Mta And Mtad On Root Dentin Fracture Resistance, Sunil Ilapogu

Loma Linda University Electronic Theses, Dissertations & Projects

Various materials are used for the treatment of immature teeth that have been subjected to trauma or decay. It is not well established what effect these materials may have on the immature root dentin. A concern would be the resistance to fracture of the remaining root dentin. The purpose of this study was to compare the resistance of fracture of bovine teeth treated with sodium hypochlorite, calcium hydroxide, gray MTA and gray MTA in conjunction with MTAD after certain periods of time. One hundred and ninety five freshly extracted, intact bovine incisors were prepared using a modified Haapasalo and Orstavik …

Levels Of Intravenous Enterococcus Faecalis That Cause Heart Colonization, Louis Zane Stromberg

Loma Linda University Electronic Theses, Dissertations & Projects

While previous studies have shown that presence of bacteria in systemic circulation can cause infective endocarditis, there is no information on the specific amount of bacteria necessary to cause this condition. The purpose of this study was to establish the minimum level of circulating bacteria that will cause colonization of damaged heart valves in rats. Fifty-two Sprague-Dawley rats were anesthetized and their heart valves were damaged using an established protocol. A clinical isolate of Enterococcus faecalis was transformed with a plasmid bearing the luxF and Chloramphenicol cassettes to label the bacteria with the light-emitting protein. After four weeks, the rats …

Detection Of Bacteria To Dental Tissue By Low-Light Imaging, G-Hong Robert Hsu

Loma Linda University Electronic Theses, Dissertations & Projects

Bacteria have been shown to play an important role in the development of pulp and periradicular disease. The source of the infective bacteria is most often the oral cavity. Previous studies have detected bacteria in teeth that are structurally intact that seemingly have no communication intraorally. Anachoresis has been proposed as a mechanism for localizing circulating bacteria to such teeth. In several previous bacteriologic anachoresis studies, bacteria have been found to localize in inflamed dental tissues. The criticism most commonly associated with these investigations has been the potential contribution of contaminant bacteria resulting in false positive findings.

Low-light image analysis …

Use Of A Portland Cement Accelerator With Mineral Trioxide Aggregate, M. Scott Monts

Theses and Dissertations

The use of Mineral Trioxide Aggregate (MTA) is gaining popularity among clinicians. Despite the many ideal qualities it possesses, it is often difficult to manipulate and often requires a second appointment for placement of a restoration to allow for setting. If the time to set of MTA can be accelerated to a single appointment time frame without significantly altering its properties, then MTA may gain even wider acceptance. The purpose of this study is to identify the percentage of a Portland Cement Accelerator (PCA), that when added to MTA, will decrease the time to set of MTA towards a single …

An In Vitro Evaluation Of The Elements Apex Locator Using The Endo Q System, Steven Andrew Brofsky

Theses and Dissertations

The objective of this study was two-fold: 1) to determine the accuracy of the Elements Apex Locator and 2) to compare the accuracy of the alginate and Endo Q models as in-vitro apex locator testing devices. Twenty teeth were decoronated at the CEJ and triplicate measurements were made using the Elements Apex Locator. All measurements were made to the apex reading of the apex locator. True length was established by visualizing the file tip at the apex with a dental operating microscope. Measurements were then taken with the teeth mounted in an alginate model and then in the Endo Q …

Torsional Testing Of Race, K3 And Profile Nickel Titanium Endodontic Files, Sean D. Fessenden

Theses and Dissertations

Rotary endodontic instruments have different cross sectional designs that may effect their resistance to torsional stress. The purpose of this study is to evaluate the static torsional properties of two nickel titanium files that have recently been introduced for use in endodontics and compare them to the same size Profile instruments. Ten new files of each brand and size were tested. The files tested were: RaCe 25 tip 0.02, 0.04, 0.06 taper, K3 and Profile 25 and 40 tip in 0.02, 0.04 and 0.06 taper. The diameter of each file was measured at 3mm from tip. The last three millimeters …

Physical And Chemical Properties Of A New Mineral Trioxide Aggregate Material, David Lowell Spencer

Theses and Dissertations

The objective of this study was to compare the time to final set and compressive strength of the white mineral trioxide aggregate (MTA) formulation to the original grey MTA. To test compressive strength, each MTA formulation was placed into Teflon split molds for four hours at 37° Celsius (C) and 100% humidity. Compressive strength of both MTA formulations was measured at 24 hours (n=12) and 21 days (n=19) using an Instron Testing Machine. For determination of time to final set, each MTA formulation (n=6) was placed into a metal mold and maintained at 37° C and 100% humidity while setting. …

Effects Of Various Hemostatic Agents On Bone, David Daryl Roland

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies have evaluated the effects of various hemostatic agents on radicular tissues following apical surgery. The purpose of this study was to examine the early osseous responses to seven hemostatic agents under identical conditions in rabbits. Sixteen adult male New Zealand white rabbits were used for this study. Following anesthesia, utilizing a midline submandibular incision, standardized bony defects were prepared on the lateral-superior regions of the mandible. Test materials were placed using standardized volumes and exposure times. Bone wax, Surgicel, Capset, alginate, Cut-Trol, Hemogin-L, and silver nitrate were compared to control sites irrigated with saline. Test materials or controls …

Effects Of Mtad On Some Physical Properties Of Enamel And Dentin, Tanya Kristina Machnick

Loma Linda University Electronic Theses, Dissertations & Projects

Recently, a Mixture of Tetracycline, an Acid, and a Detergent (MTAD) has been advocated to remove smear layer and disinfect canals. The purpose of this study was to evaluate the effect of MTAD the flexural strength and modulus of elasticity of dentin as well as its effect on the bond strength to enamel and dentin. In Part I, dentin bars were randomly assigned to eight groups treated either with various concentrations of NaOCl (5.25%, 2.65%, 1.31%, 0.66%), 17% EDTA, MTAD, saline, or according to a clinical protocol with 1.3% NaOCl and then 5 min of MTAD. …

Effect Of Ca(Oh)2 On Survival Ability Of A Bacterial Mixture: An In Vitro Study, Nishan Antranik Odabashian

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this in vitro investigation was to evaluate the antibacterial effect of calcium hydroxide on a mixture of nine bacteria associated with endodontic infections at different time intervals and to examine the survival of the same bacteria when in mixture. A total of 102 teeth were used in the first part of the experiment. Eighty teeth were used in eight experimental groups of 10 each, 16 teeth were used for positive and negative controls, and six teeth were used for scanning electron microscopy (SEM). Nine species of bacteria were used in both experiments. These consisted of Enterococcus faecalis, …

K3 Endo, Pro Taper, And Pro File Systems: Breakage And Distortion In Severely Curved Roots Of Molars, Matthew Todd Ankrum

Theses and Dissertations

K3 ENDO, PRO TAPER, AND PRO FILE SYSTEMS: BREAKAGE AND DISTORTION IN SEVERELY CURVED ROOTS OF MOLARS.By Matthew T. Ankrum, D.D.S.A Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University.Virginia Commonwealth University, 2003Major Director: Gary R. Hartwell, D.D.S., M.S.Chairman and Professor, Department of EndodonticsIt was the aim of this study to investigate the incidence of file breakage and distortion when the Pro Taper, K3 Endo and ProFile systems were used to instrument canals in the severely curved roots of extracted molars.Forty-five roots of extracted mandibular and maxillary molars with curvatures …

The Effect Of Endodontic Solutions On Resorcinol-Formalin Paste In Teeth, Madelyn Gay Gambrel

Theses and Dissertations

This study determined if any of six endodontic solutions would have a softening effect on resorcinol-formalin paste in extracted teeth, and if there were any differences in the solvent action between these solutions. Forty-nine single-rooted extracted teeth were decoronated two mm coronal to the CEJ, and the roots sectioned apically to a standard length of 15 mm. Canals were prepared to a 12mm WL and a uniform size with a #7 Parapost drill. Teeth were then mounted in a cylinder ring with acrylic. The resorcinol-formalin mixture was placed into the canals and was allowed to set for 60 days in …

The Effect Of Chlorhexidine Gluconate As An Endodontic Irrigant On The Apical Seal: Long-Term Results, David B. Ferguson

Theses and Dissertations

The purpose of this study was to determine whether chlorhexidine gluconate (0.12%), used as an endodontic irrigating solution would affect the apical seal of three root canal cements. One hundred extracted human single-canal teeth were divided into 9 experimental groups of 10 teeth each, in addition to a positive and negative control group of 5 teeth each. The teeth were decoronated at the level of the cementoenamel junction, accessed, instrumented to a Master Apical File #50, irrigated with either sterile saline, 5.25% NaOCl or 0.12% chlorhexidine gluconate, and dried using paper points. Obturation was accomplished using lateral condensation and one …

Identification Of Hard Tissue Using Dentin Sialoprotein (Dsp) As A Marker, Wallis E. Andeline

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to identify the early hard tissue formed in experimental pulp exposures capped with calcium hydroxide, mineral trioxide aggregate (MTA) or bone morphogenetic protein-7 (BMP-7) using dentin sialoprotein (DSP) as a marker. The pulps of eighty-five maxillary first, second and third molar teeth from twenty male rats were experimentally exposed. The exposed pulps were capped with calcium hydroxide followed by restoration with amalgam (n = 20), with MTA alone as a pulp capping agent and final restoration (n = 20) or with BMP-7 followed by restoration with MTA (n = 20). Ten teeth with Class …

Hard Tissue Healing Adjacent To Fresh Or Set Mta As Root-End Filling Material, Erol S. Apaydin

Loma Linda University Electronic Theses, Dissertations & Projects

Mineral trioxide aggregate (MTA) has been shown to promote regeneration of periradicular tissues when used as a root-end filling material. The purpose of this study was to compare the effect of fresh MTA with set MTA on hard tissue healing following periradicular surgery.

Under general anesthesia, the root canals of twenty-four mandibular premolars in four 2-year-old beagle dogs were filled with MTA. Two weeks later the root-ends of half of the samples were surgically exposed and resected to the level of set MTA within the canals. After exposing and resecting the other 12 root-ends, class I cavities were prepared in …

The Effect Of Endodontic Solutions On Resorcinol-Formalin Paste, Ronald Nicholas Vranas

Theses and Dissertations

This study determined if any of four endodontic solutions would have a softening effect on resorcinol-formalin paste and if there were any differences in the solvent action between these solutions. Resorcinol, formalin and zinc oxide were mixed and allowed to set for 30 days. The solutions tested were 0.9% sodium chloride, 5.25% NaOCl, chloroform and Endosolv R. Seven samples per solution were tested and an additional seven samples served as controls. Each sample was saturated with one of the solutions and the depth of penetration was tested at 1 min, 2 min, 5 min, 10 min and 20 min using …

Placement Of Mineral Trioxide Aggregate Using Two Different Techniques, Anita Aminoshariae

Theses and Dissertations

AbstractTHE PLACEMENT OF MINERAL TRIOXIDE AGGREGATE USING TWO DIFFERENT TECHNIQUESBy Anita Aminoshariae, D.D.S.A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth UniversityVirginia Commonwealth University, 2003Major Director: Gary R. Hartwell, D.D.S., M.S.Chairman and Professor, Department of EndodonticsThe purpose of this study was to determine if the adaptation of Mineral Trioxide Aggregate (MTA) to the walls of the samples would differ when placed into simulated root canals of varying length using two different placement and condensation methods. Hand condensation was compared to ultrasonic condensation. Eighty polyethylene tubes were divided into four groups …

Cleaning Efficiency Of Nickel Titanium Gt And .04 Rotary Files When Used In A Torque Controlled Rotary Handpiece, Calvin Buford Suffridge

Theses and Dissertations

This study determined if the cleaning efficiency of NiTi rotary files in an endodontic electric handpiece using a no torque control setting was superior to that obtained when using the torque control feature. Fifty extracted human anterior teeth with straight canals were divided into two groups of 20 and two control groups of 5. Canals were instrumented with GT and .04 Profile NiTi files until a size 35 advanced to working length. Samples were sectioned, the apical 6 mm of the canal was photographed (x20) and projected onto a 3 x 4 foot grid with squares measuring 0.5 inches each. …

Working Length Determination In Palatal Roots Of Maxillary Molars, Melanie A. Kim-Park

Theses and Dissertations

The aim of this study was to determine if a buccal curvature in the palatal roots of maxillary molars affected the clinician’s ability to accurately determine working length. Twenty-seven extracted, human maxillary molars were sorted by palatal root curvatures as J- and C-type and the angle of curvature was determined. Straight-line access was made and a #20 file was placed into the canal until the tip was visible at the apical foramen then withdrawn. The file, tooth and calibration wire were radiographed on one image using the RVG. Actual (file) and radiographic (tooth) lengths were determined using the RVG ruler. …

Hard Tissue Forming Potential Of Mta Compared To Common Root-End Filling Materials, Nooshin Noghreian

Loma Linda University Electronic Theses, Dissertations & Projects

An ideal characteristic of root-end filling materials used in endodontics is the ability to enhance hard tissue formation. Studies have shown that MTA has the potential to enhance hard tissue formation when placed in contact with periradicular tissues. The mechanisms involved in hard tissue formation of MTA and other root-end filling materials have not been completely elucidated. The purpose of this investigation was to study the mechanism of hard tissue formation of commonly used root-end filling materials and MTA by evaluating alkaline phosphatase (ALP) activity and cell layer protein. Extracts of materials tested in this experiment were added to the …

Disinfection Of Dentin By Intracanal Laser Irradiation: An In Vitro Model, Silvia Cristina Mafra Cecchini

Loma Linda University Electronic Theses, Dissertations & Projects

A possible cause for root canal failure is the persistence of bacteria that have colonized dentinal tubules. To reduce this risk and, if possible, to also shorten the time consuming endodontic therapy, new equipment and materials are constantly being introduced. The aim of the present investigation was to study the effect of disinfection of dentinal tubules by intracanal laser irradiation using an in vitro model. The groups irradiated by various lasers were compared with calcium hydroxide, a material frequently used as intracanal medication between appointments. Freshly extracted, intact bovine incisors were used. The root cementum was removed and the teeth …

Anti-Inflammatory Agents And The Modulation Of Replacement Root Resorption, Geoffrey Toshio Okada

Loma Linda University Electronic Theses, Dissertations & Projects

Replacement resorption (RR) occurs following severe injury to the periodontal ligament (PDL). It has been suggested that inflammatory reactions precede RR. The purpose of this study was to examine and compare histologically the effect of topical application of two anti-inflammatory medications and stannous fluoride (SF) on the development of RR. Thirty-four roots of beagle dog mandibular 2nd, 3rd, and 4th premolars received root canal therapy. They were then extracted and left to bench dry for one hour. Following removal of their PDLs, they were soaked for five minutes in either 10 µg/ml ketorolac (n=10), 16 µg/ml of dexamethasone (n=10), or …

Periradicular Response Of Immunodeficient Rats To Mechanical Pulpal Exposure, James E. Stich

Loma Linda University Electronic Theses, Dissertations & Projects

Periradicular lesions develop as a result of the interaction between root canal irritants and the immune system. The purpose of this study was to investigate the periradicular response of immunodeficient rats to their oral flora. Twenty Sprague-Dawley rats received a total body irradiation dose of 750 cGy one week prior to the investigation. The pulps of the mandibular first molars of these animals and six nonirradiated rats were exposed mechanically with a ½ round bur and left open to the oral cavity. Additional irradiation (350 cGy) was administered bi-weekly to maintain immunosuppression. Periradicular specimens were obtained after two and four …

Effect Of Obturation And / Or Coronal Seal On The Success Of Root Canal Therapy : An In Vivo Histologic Investigation, Douglas Snider

Loma Linda University Electronic Theses, Dissertations & Projects

Numerous studies have examined coronal leakage with in vitro protocols. A search of the literature showed the absence of a long term in vivo, histologic study, examining the effect of coronal and/or radicular leakage on periradicular health.

The purpose of this study was to evaluate the effect of obturation and / or coronal seal in preventing the formation of periradicular lesions in dogs over time. The study was conducted on six beagle dogs. Premolars were cleaned and shaped. Sixteen roots in each dog were randomly assigned to one of four treatment groups of equal size. Group one was obturated using …

An Evaluation Of Root End Filling Materials Using Endotoxin, Hong-Ming Tang

Loma Linda University Electronic Theses, Dissertations & Projects

Mineral Trioxide Aggregates (MTA) was recently developed at Loma Linda University. It has been shown to possess good sealing ability when tested with dye, bacteria, and a fluid filtration technique.

Endotoxin is a component of the cell wall of Gram negative bacteria. It has been proposed that it may play a role in the pathogenesis of periradicular lesions. Previous studies have demonstrated that MTA can prevent the leakage of bacteria. However, the bacterial products were not tested during these studies.

This study used endotoxin to compare the sealing ability of SuperEBA, IRM, amalgam, and MTA.

The results showed that MTA …

The Effect Of Systemic Doxycycline On Alveolar Bone Loss Following Periradicular Surgery, G. Reed Cummings

Loma Linda University Electronic Theses, Dissertations & Projects

Studies have shown an average of 0.5 mm to over 1.0 mm of bone loss following full thickness flap reflection. Recent investigations have revealed that the tetracycline family of antibiotics can prevent bone loss. The purpose of this study was to determine the effect of systemic Doxycycline on crestal alveolar bone loss following periradicular surgery in Beagle dogs.

The experiment was divided into two phases. The first phase served as the control (Non-Doxycycline), the second phase as the experiment (Doxycycline). Full thickness flaps were reflected in the mandibular left or right quadrant (control side) of five Beagle dogs. Using a …

The Effect Of Root End Demineralization On Cementogenesis : A Long Term Investigation, Hamid R. Abedi

Loma Linda University Electronic Theses, Dissertations & Projects

Craig and Harrison¹² examined the effect of demineralization of resected root ends on wound healing following periradicular surgery. Based on its microscopic evaluations from 4-45 days, it was proposed that demineralization of resected root ends enhances cementogenesis. The purpose of this study was to investigate the longer term effects of demineralization on cementogenesis using Mineral Trioxide Aggregate (MTA) or amalgam as root end filling materials. After completion of root canal therapy and endodontic surgery on seventy-two roots of mandibular second, third and fourth premolars of six beagle dogs, 32/72 of the root ends at random were etched with 50% …

An Animal Model For Development Of Pulpal Inflammation, John W. Masters

Loma Linda University Electronic Theses, Dissertations & Projects

Several animal models have been proposed to develop pulpal inflammation. Procedures recommended in these models have many variables and have not produced consistent results. The purpose of this study was to create pulpal inflammation using the Nd:YAG laser.

Forty-five cuspids of 12-18 month old beagle dogs were lased at 5, 7.5, and 10 watts (W) for 20 seconds with a 600 micron contact probe. Five cuspids were not lased but were used as controls. Following laser application, the teeth were extracted at intervals of 3, 7, and 30 days. They were then fixed in 10% formalin, decalcified, sectioned, and stained …