Dentistry Commons^™

Use Of Cone Beam Computed Tomography In The Determination Of Mental Foramen Location In Relation To Mandibular 1st And 2nd Premolars, Sanjay Bhagchandani

Theses and Dissertations

The purpose of this study was to use existing Cone Beam Computer Tomography images to determine the vertical and horizontal location of the mental foramen in relation to the mandibular first and second premolars, as well as the distance in millimeters from the apex of each. The distance from the inferior border of the foramen to the inferior border of the mandible was also recorded. The average distance from the apices of the mandibular first and second premolars to the mental foramen was 7.43mm (SD= 1.97) and 5.30mm (SD=1.65) respectively. The foramen was located 11.44mm (SD=1.49) from the inferior border …

Endodontic Residents’ Understanding Of Biostatistics: A 2010 Survey Of Endodontic Residents In The United States, Paul Letellier Jr.

Theses and Dissertations

Endodontic residents must keep current with clinical information to practice evidence- based dentistry. To do so, endodontic residents must access research papers and interpret results. This requires a knowledge of biostatistics. However, the biostatistical knowledge of endodontic residents is relatively unknown. The purpose of the study was to assess the biostatistical knowledge of endodontic residents using a survey instrument to prove or reject the hypothesis that there exists a lack of understanding of biostatistic principles among endodontic residents. A survey consisting of 29 questions querying attitudes and biostatistical knowledge was distributed to 230 endodontic residents and returned with a 32% …

Endodontic Education And Educators: Who Is Teaching Our Predoctoral Students And What Methods Are Being Taught?, Ellison Turner

Theses and Dissertations

A survey was conducted to assess the current state of predoctoral endodontic education in the United States. Fifty-one schools received surveys and 73% responded. Seventy-six percent were from public schools with most having a graduate endodontic program (84%). Preclinical training most often began in the spring of second year and clinical training started in the fall of third year (each 54%). All programs that responded stated that endodontists routinely instruct students in the clinic. Sodium hypochlorite 2.5% was the irrigation of choice. Calcium hydroxide was the most common intracanal medicament. Cold lateral condensation with gutta-percha was the most frequently indicated …

Prospects And Pits On The Path Of Biomimetics: The Case Of Tooth Enamel, Vuk Uskoković

Pharmacy Faculty Articles and Research

This review presents a discourse on challenges in understanding and imitating the process of amelogenesis in vitro on the molecular scale. In light of the analysis of imitation of the growth of dental enamel, it also impends on the prospects and potential drawbacks of the biomimetic approach in general. As the formation of enamel proceeds with the protein matrix guiding the crystal growth, while at the same time conducting its own degradation and removal, it is argued that three aspects of amelogenesis need to be induced in parallel: a) crystal growth; b) protein assembly; c) proteolytic degradation. A particular emphasis …

Antibiotic Use By Members Of The American Association Of Endodontics: A National Survey For 2009- A Follow Up From The Report In 1999, Pye Kyu

Theses and Dissertations

The purpose of this study was to determine the changes in prescribing habits of active members of American Association of Endodontics (AAE) with regards to antibiotics in comparison to the findings reported by Yingling et al. in 1999. The invitations to take the online survey were sent via email to 2593 active members. A response rate of 37.75% was obtained. It was determined to be adequate for analysis and for comparison to the results obtained by Yingling et al. Comparisons between the percentages shown in this survey and the previous survey were tested using a z-test. An ANOVA model was …

Frequency And Distribution Of Endodontically Treated Teeth, Hina Ahmed, Durr E. Sadaf, Munawar Rahman

Section of Dental-Oral Maxillofacial Surgery

Objective: To determine the distribution and pattern of carious teeth involvement in permanent teeth requiring endodontic treatment. Study Design: Cross-sectional study. Place and Duration of Study: Dental Section of The Aga Khan University Hospital, Karachi, from September 2004 to March 2005. Methodology: Data was collected from the dental records of patients. Tooth was the unit of evaluation. Variables studied were demographics, tooth type, etiology of endodontic treatment and pattern of caries involvement. Data was analyzed using chi-square test and Fischer’s exact test. Results: The total number of patients was 190; total number of teeth involved were 235. Females had more …

Comparative Analysis Of Torsional Strength Between Profile® Gt® And Gt® Series X(Tm) Nickel Titanium Rotary Instruments, Jake Reynolds

Theses and Dissertations

The purpose of this study was to compare the resistance to fracture by the twisting of two nickel titanium (NiTi) rotary file systems. The Profile® GT® (GT) and the GT® Series X(TM) (GTX) files were tested to analyze the maximum torsional strength and the maximum angular deflection at the time of separation of the files. For each system, ten new files were tested at each of the following eight taper/size designations for a total of 160 files: 20/0.04, 20/0.06, 30/0.04, 30/0.06, 30/0.08, 40/0.04, 40/0.06, and 40/0.08. The American National Standards Institute / American Dental Association Specification No. 28 was implemented …

Comparing Cyclic Fatigue Of The New Gt® Series X(Tm) Files To The Endo Sequence™ Rotary Instruments, Nathan Wayment

Theses and Dissertations

The purpose of this study was to examine the number of rotations to failure of two different rotary file systems, EndoSquence Brassler USA (Savannah, GA) and GT(TM) series X(TM). Files sizes 20,30,40 with 0.04, 0.06 tapers of GT series X and Endo Sequence files size and taper used were 20, 30, 40 with 0.04 and 0.06 taper. Like tip and tapers were compared between systems. All files tested were 25mm in length. Files were allocated into 12 groups of 10 files each, and mounted to a universal testing machine. Each file was rotated at 300 rpms until fractured occurred. The …

Comparing Cyclic Fatigue Of The New Gt® Series Xtm Files To The Original Profile® Gt® Rotary Instruments, Steven Osmond

Theses and Dissertations

The purpose of this study was to test the number of rotations to fracture of the M-Wire GT® Series X(TM) rotary files compared to the original ProFile® GT® rotary files in a simulated curved canal. Eighty GT® Series X(TM) files of 25mm length were divided into eight groups of ten, one for each of the new GT® Series X(TM) files. Eighty original ProFile® GT® files of 25mm length were divided into eight groups of the same tip and taper sizes consistent with the GT® Series X(TM) file groups. Files were rotated at 300 rpm. While the angle may have slightly …

Effect Of Short Exposure Of Naoci/Edta On E. Faecalis In Extracted Human Teeth, Rylan N. Gustafson

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this project was to study the antibacterial effect of the short exposure of 5.25% NaOCl and 17% EDTA on eight strains of Enterococcus faecalis in extracted human teeth. The crowns of 240 single rooted teeth were removed and the canals were instrumented to ISO 0.36. The canals were irrigated with 5.25% NaOCl and 17% EDTA, autoclaved and separated into eight groups of 30 teeth consisting of 20 experimental teeth, 5 positive and 5 negative controls. Each group was inoculated with one of eight different strains of E. faecalis in BHl broth and incubated for four weeks. The …

Effect Of Gutta Percha On The Retention Of A Post Using Different Cements, Saeda H. Basta

Loma Linda University Electronic Theses, Dissertations & Projects

This study evaluated the effect of residual gutta percha on the retention strength of prefabricated post cemented with four different cements. Forty intact mandibular single canal canines or premolars were selected for standardized size and quality, endodontically treated, and decoronated to the cementoenamel junction. A post space was prepared to accommodate Para post XP size 4 (Coltene, Whaledent Inc., Cuy Falls, Ohio) to a depth of 8 mm. The Obtura heated gutta percha system was used to inject a very thin line of gutta percha along one lateral wall to the depth of the future post. Forty obturated teeth were …

Contamination Of Dental Waterlines: Efficacy Of Seven Waterline Treatments And Three In-Office Bacteria Test Kits, Adam Davis

Theses and Dissertations

This study compared seven dental unit water line (DUWL) treatments and three in-office bacteria test kits. Sodium hypochlorite (NaOCl) 1:10 in tap water weekly; 3 drops of NaOCl in 1 liter of water; Dentapure® DP 40; ICX™ tablet; Sterilex® Ultra powder; Lines™; and Selective Micro® Dental-Clean. Traditional culture technique was compared to HPC Dental Sampler; Aquasafe™ Dental Unit Water Line Test Kit; and Bacteria in Water Test Kit. Eight dental units in the Virginia Commonwealth University Graduate Endodontic Clinic were randomly assigned treatment regimens. Samples were taken weekly initially and after flushing for 1 minute. In conclusion NaOCl hypochlorite 1:10 …

Enzymatic Processing Of Amelogenin During Continuous Crystallization Of Apatite, Vuk Uskoković, M.-K. Kim, W. Li, S. Habelitz

Pharmacy Faculty Articles and Research

Dental enamel forms through a protein-controlled mineralization and enzymatic degradation with a nanoscale precision that new engineering technologies may be able to mimic. Recombinant fulllength human amelogenin (rH174) and a matrix-metalloprotease (MMP-20) were employed in a pHstat titration system that enabled a continuous supply of calcium and phosphate ions over several days, mimicking the initial stages of matrix processing and crystallization in enamel in-vitro. Effects on the self-assembly and crystal growth from a saturated aqueous solution containing 0.4 mg/ml rH174 and MMP-20 with the weight ratio of 1:1000 with respect to rH174 were investigated. A transition from nanospheres to fibrous …

Density Of Gutta Percha By Weight In Straight Root Canals And Curved Root Canals After Single Cone, Cold Lateral, And Warm Vertical Condensation, Gerald Clay Sparrow

Theses and Dissertations

The purpose of this study was to compare the density of gutta percha following three different obturation techniques using two split-tooth models. One split-tooth model was constructed with a straight rooted maxillary incisor and the other with the curved palatal root of a maxillary molar. Each tooth was obturated using single cone, cold lateral, and warm vertical obturation techniques without sealer. Each obturation technique was performed 20 times for each of the root systems. The weights of the gutta percha were recorded for each root type and obturation technique by subtracting the post-fill weight from the pre-fill weight of the …

A Comparison Of Five Radiographic Systems To D-Speed Film In The Detection Of Artificial Bone Lesions, David Lloyd Hadley

Theses and Dissertations

The purpose of this study was to compare three direct digital sensors (Kodak 6100, Schick CDR, and Dexis PerfectSize), a phosphor plate system (OpTime), and F-speed film to standard D-speed film in the detection of artificial bone lesions prepared in mandible bone sections. Multiple artificial bone lesions were prepared at varying depths in the cortical bone. Specimens were imaged with six different radiographic systems. Radiographs were randomly presented to nine different observers. A logistic regression analysis indicated that the ability of the different radiographic systems to detect the bone lesions was significantly different at the mean percentage of cortical bone …

The Use Of Implants Vs. Endodontics: Practitioner Attitudes In 2007, Gardiner Mckay Packer

Theses and Dissertations

The purpose of this study was to determine what factors influence dentists when deciding whether to place an implant or perform endodontic retreatment. Null hypothesis: Dentists today are no more likely to place an implant than to perform endodontic retreatment. A twelve-item questionnaire was mailed to 525 general dentists and specialists who are members of the Richmond Dental Society. Response rate was 61.9%. The questionnaire included items on demographics, practice profile and cases of failing endodontic therapy which participants were asked to consider and chose between endodontic retreatment or implant placement. The relationship between the treatment choices and the characteristics …

The Effect Of Mtad On Eight Strains Of E. Faecalis In Contaminated Root Canals, Bradley M. Newberry

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this investigation was to determine the antimicrobial effect of Biopure MTAD (a mixture of a tetracycline isomer, an acid, and a detergent) as a final irrigant on eight strains of Enterococcus faecalis (E. faecalis) in contaminated root canals of extracted human teeth. In addition, the Minimum Inhibitory Concentration (MIC) and Minimum Lethal Concentration (MLC) of MTAD were also measured on the same strains of bacteria. Two-hundred and forty extracted human teeth were instrumented using 1.3% NaOCl followed by 17% EDTA to remove the smear layer. The teeth were randomly contaminated with one of eight strains of E. …

Detoxification Of Lipopolysaccharide By Endodontic Sealers, Dominic Côté

Loma Linda University Electronic Theses, Dissertations & Projects

Bacterial lipopolysaccharide (LPS) has been implicated in the pathogenesis of pulpal and periapical diseases. Several studies have evaluated the ability of various medicaments and irrigants used during root canal therapy to chemically detoxify LPS. The purpose of this study was to evaluate the ability of some endodontic sealers to detoxify LPS. This investigation compared the quantities of TNF-α released by human monocytes exposed to LPS or LPS pre-treated with sealers. The sealers tested were: Pulp Canal Sealer EWT (PCS), AH Plus (AH), and Sealapex (SA). Ca(OH)₂ and water (H2O) were respectively used as the positive and negative control materials. …

A Comparison Of Flexural Fracture Of Three Different Nickel-Titanium Rotary File Systems, Matthew Warren Lloyd

Theses and Dissertations

The purpose of this study was to compare the number of rotations to failure of three different rotary file systems. ProFile, Sequence, and Liberator files in sizes 25 and 40 with 0.04 taper were divided into groups of five and rotated against a grooved metal block mounted to a Universal testing machine at 31 and 34 degrees. Each file was rotated at 300 rpm until fracture occurred. The number of rotations to fracture were calculated. Use of a three-way ANOVA and Tukey's HSD multiple comparison tests revealed significant differences for the angle of deflection, size, and type of file. An …

Sodium Hypochlorite's Effect On Nickel-Titanium Rotary Instruments And Its Effect On Resistance To Fracture, Michael Shane Smith

Theses and Dissertations

The purpose of this study was to examine the effect of partial and total immersion in sodium hypochlorite on nickel-titanium rotary files and to determine whether resistance to fracture was influenced by the immersion time. One hundred K3™ and 100 ProFile® rotary files were either partially or totally immersed in 5.25% sodium hypochlorite for zero, one, five, thirty, or sixty minutes. After immersion, files were subjected to cyclic fatigue testing. Time to fracture was recorded and analyzed by a two-way ANOVA. Tukey's honest significant difference was used to identify any differences in immersion times. Within all ProFile groups and partial …

Immunohistochemical Study Of Phenotypes Of Dendritic Cells In Dental Pulps From Non-Carious And Carious Teeth, Melissa A. Harmon

Theses and Dissertations

Mature dendritic cells (DCs) in inflamed tissues may promote inflammation but the status of DCs in pulpitis is not known. We hypothesized that DC maturation would correlate with carious lesion depth and that CD4+ cells would be found in association with mature DCs. Pulps were collected from teeth exhibiting: (I) no caries (n=9), (II) shallow dentinal caries (n=5), and (III) deep caries (n=9). Pulpal tissues were cryo-sectioned and positive cells were examined with immunohistochemistry, Mature DCs (CD83+) were almost exclusively restricted to pulps from deep caries. Furthermore, CD209+ DCs in deep caries were elevated over other groups and CD209+ cells …

An Invitro Leakage And Viscosity Analysis Of Root End Filling Materials, Paul D. Clark

Theses and Dissertations

The purpose of this study was to determine if the viscosity of MTA Angelus Fluid is lower than that of Pro Root MTA and MTA Angelus; and to compare the viscosity, leakage and particle size of these materials to determine whether a relationship exists between these properties. The viscosity of each material was measured and compared with the Student's t test. MTA Angelus Fluid's viscosity was significantly lower than the other two materials tested. Microleakage of root end fillings was assessed in a passive diffusion model. Leakage groups were compared with a one-way ANOVA (p < 0.05). No significant difference was found. Particle size and shape were evaluated with the SEM. MTA Angelus Fluid has a lower viscosity than the other materials tested. There was no significant difference in the sealing ability of the three materials tested and there was no apparent variation in each material's particle size or shape.

Effects Of Diabetes Mellitus On The Healing Of The Dental Pulp, Stuart Evan Garber

Loma Linda University Electronic Theses, Dissertations & Projects

Diabetes Mellitus (DM) has been implicated as a factor affecting healing. The purpose of this study was to use the healing of experimentally exposed pulps subsequent to pulp capping as a model to determine the effect of DM on healing.

Twenty-two Sprague-Dawley rats were divided into two groups of eleven animals each. In one group, DM was induced by injection of 70 mg/KG of streptozotocin. In the other group, the animals were injected with sterile saline. Under anesthesia with Ketamine and Xylazine, the pulps of the maxillary first molars of all rats were exposed using a 1/16 round bur under …

Treponema Denticola In Disseminating Endodontic Infections, F. Foschi, Jacques Izard, H. Sasaki, V. Sambri, C. Prati, R. Müller, P. Stashenko

Department of Food Science and Technology: Faculty Publications

Treponema denticola is a consensus periodontal pathogen that has recently been associated with endodontic pathology. In this study, the effect of mono-infection of the dental pulp with T. denticola and with polymicrobial “red-complex” organisms (RC) (Porphyromonas gingivalis, Tannerella forsythia, and T. denticola) in inducing disseminating infections in wild-type (WT) and severe-combined-immunodeficiency (SCID) mice was analyzed. After 21 days, a high incidence (5/10) of orofacial abscesses was observed in SCID mice mono-infected with T. denticola, whereas abscesses were rare in SCID mice infected with the red-complex organisms or in wild-type mice. Splenomegaly was …

The Outcome Of Mta As A Root End Filling Material: A Long Term Evaluation, Christopher M. Sechrist

Loma Linda University Electronic Theses, Dissertations & Projects

Periradicular surgery is a viable option to save natural teeth when non-surgical treatment fails or when endodontic retreatment is not feasible or contraindicated. Laboratory and animal studies have demonstrated that MTA is biocompatible, provides an excellent seal against penetrating bacteria, and promotes hard tissue healing. The purpose of this study was to provide long term (>3 years) clinical evidence for its use as a root-end filling material in endodontics. The clinical records of 294 patients who had MTA used during endodontic treatment from 1996 to 2001 were reviewed. From these, 75 patients whose root end cavities had been filled …

Treatment Outcome Of Root Perforations Repaired With Mineral Trioxide Aggregate, Stephen H. Paik

Loma Linda University Electronic Theses, Dissertations & Projects

Root perforations during root canal therapy have a significant negative impact on long-term prognosis of teeth. Proper treatment is critical in managing these accidental procedures. Laboratory and animal studies have demonstrated that Mineral Trioxide Aggregate (MTA) is biocompatible, provides an excellent seal against penetrating bacteria, and promotes hard tissue healing. The purpose of this study was to determine the long term treatment outcome of root perforations repaired with MTA.

Ninety-nine records from the Graduate Endodontic Clinic at Loma Linda University School of Dentistry from 1996 to 2001 were reviewed. Clinical and radiographic evaluations were completed. Three independent examiners evaluated digitized …

Histological Comparison Of White And Gray Mta In Repair Of Furcation Perforations, Miguel Elias Mego

Loma Linda University Electronic Theses, Dissertations & Projects

Mineral trioxide aggregate (MTA) has been shown to promote regeneration of the periodontal apparatus when used as a repair material in furcation perforations. Two variations of MTA (Gray and White) have been introduced to the dental market. The purpose of this study was to histologically compare the in vivo response to immediate furcation perforation repair using gray or white MTA in beagle dogs.

Under general anesthesia, non-surgical root canal therapy and furcal perforations were performed on sixteen mandibular premolars of eight 2-year old beagle dogs. The perforations were immediately repaired with either white (n=8) or gray (n=8) MTA. The animals …

A Quantitative Comparison Of The Fill Density Of Mta Produced By Two Different Placement Techniques., Priscilla Yeung

Theses and Dissertations

The purpose of this study was to quantitatively compare the fill density of MTA produced by hand condensation and hand condensation with indirect ultrasonic activation. Thirty acrylic block with 30 degree curved canals (group C) and 30 with straight canals (group S) were instrumented to a final apical size of 45 of 0.06 taper crown-down technique. After irrigating with water and drying with paper points, each block was weighed to the nearest 0.0001g with a digital electronic balance. In half of the specimens, chosen at random, the canal first filled with MTA using the hand condensation method (H) then weighed. …

The Predictive Ability Of Specific Questions Related To Symptoms In The Diagnosis Of Endodontic Disease, Boyd Aaron Vaughn

Theses and Dissertations

The purpose of this study was to test the predictive ability of specific questions in diagnosis of pulpal and periradicular disease in a dental school population. 210 patients were recruited to fill out a questionnaire, and undergo a clinical examination for pulpal and/or periradicular disease.The Questionnaire asked if the patient had in the last 6 months: 1. a toothache that kept them up at night 2. a toothache that required pain killers 3. facial swelling caused by a tooth 4. injury to any teeth 5. a broken tooth 6. a tooth darker in color than the surrounding teeth 7. a …

Periplasm Organization In Treponema Denticola As Studied By Cryo-Electron Tomography, Jacques Izard, C.-E. Hsieh, C. A. Mannella, Ronald J. Limberger, M. Marko

Department of Food Science and Technology: Faculty Publications

As a spirochete, the genus Treponema is one of the few major bacterial groups whose natural phylogenic relationships are evident at the level of gross phenotypic characteristics such as their morphology. Treponema spp. are highly invasive due to their unique motility in dense media, and their ability to penetrate cell layers. This feature is associated with the helical cell body and the presence of flagellar filaments in the periplasm. Treponema denticola is an oral pathogen involved in endodontic infections and periodontal diseases. The presence and quantity of T. denticola in the subgingival biofilm is correlated with the severity of periodontal …