Other Dentistry Commons^™

Implant Success In Distracted Bone Versus Autogenous Bone-Grafted Sites, Jeffrey Allan Elo

Loma Linda University Electronic Theses, Dissertations & Projects

Endosseous implants are the treatment of choice for restoring function and reconstructing edentulous areas of the maxilla and mandible. Alveolar defects can be reconstructed by either distraction osteogenesis or autogenous bone grafting. After alveolar reconstruction, endosseous implants are used to support and retain the prosthesis for restoration of form and function. We retrospectively analyzed the success rates of endosseous implant placement in distracted versus autogenous bone graft reconstruction sites in our patient population at Loma Linda University Medical Center, Department of Oral and Maxillofacial Surgery. 82 consecutive patients requiring alveolar augmentation prior to implant placement were evaluated. All patients were …

Shear Strengths Of Three "One-Step" Self-Etching Dental Bonding Agents, Jeff G. Alcaide

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: To compare the dentin shear bond strength of three self-etching bonding agents with that of a conventional total-etch bonding system.

Materials & Method: Extracted third molars (120) were fixed in 10% formalin and randomly divided into eight groups of 15 specimens each. The specimens were mounted in acrylic resin and the surface ground to expose superficial dentin. A standardized smear layer was created by polishing the surfaces with wet 600-grit silicon carbide paper. Each adhesive system was placed on the specimen surface according to the manufacturers' instructions. The specimen then was mounted onto a standardized jig and light cured. …

Stability Of The Miniscrew-Bone Interface: Reverse Torque Values In Rabbits, Daniel John Drye

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Miniscrews are used in orthodontics as practical temporary anchorage devices (TAD's). The purpose of this animal study was to measure reverse torque values for Absoanchor 1.2 mm and Micerium 1.5mm miniscrews at 0, 2, and 12 weeks under loaded and unloaded conditions.

Methods: Ninety-six miniscrews were placed in the femora of twelve rabbits and allowed to heal for either two or twelve weeks. Half of the fixtures were loaded immediately with NiTi open coil springs producing a force of 150-200g and the other half served as unloaded controls. For each of the healing times, two and twelve weeks, …

A Comparative Study Of Conventional-Ligating And Self-Ligating Bracket Systems, Gabriela Garcia

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this research was to determine the frictional resistance of four self-ligating brackets and two conventional bracket systems using two different types of orthodontic arch wires in both wet and dry fields. Six different brands of upper right central incisor brackets with 0.018-in slots were evaluated. Group A : self-ligating bracket: Opal (Ultradent), Damon 2 (Ormco), Time (American Orthodontics), In-Ovation (GAC). Group B: conventional-ligating: Virage (American Orthodontics), and Mini-Twin (Unitek) served as the control brackets. Two different orthodontic wires of varying alloys and sections were tested: 0.016-in round stainless steel (Ormco) and 0.016x0.022 inch rectangular nickel-titanium (American Orthodontics). …

Comparison Of Different Methods Of Assessing Ridge Width Prior To Implant Placement, Lung-Cheng Chen

Loma Linda University Electronic Theses, Dissertations & Projects

The aim of this study was to compare the following 3 methods of assessing alveolar ridge dimensions prior to placement of dental implants: 1) ridge mapping measurement before surgical flap reflection using a caliper; 2) direct caliper measurement following surgical exposure of the bone, and 3) measurement using images from cone beam computerized tomography.

Sixteen subjects having 25 sites for planned implant placement or ridge augmentation were recruited. An acrylic stent was fabricated for each patient. The stent provided 3 buccal/lingual pairs of consistent measurement points for each implant site, located 4, 7 and 10 mm from the summit of …

The Effect Of Rapid Maxillary Expansion On Nasal Cavity Volume And Nasal Airway Resistance, Todd Ehrler

Loma Linda University Electronic Theses, Dissertations & Projects

This study examined the effects of Rapid Maxillary Expansion (RME). Using Cone Beam CT scanning technology and Rhinomanometry, the volume and nasal airway resistance (NAR) of the nasal cavity was measured immediately before and after RME.

27 subjects (16 female, and 11 male), ages 9-18 were enrolled in the study. After RME all subjects had a statistically significant increase in nasal cavity volume. The pre expansion group experienced a statistically significant reduction in NAR when compared to the post expansion group. Individuals with a high pre expansion NAR experienced the greatest reduction in NAR. The correlation between change in volume …

Prevalence Of Degenerative Joint Disease In A Pre-Orthodontic Adolescent Sample, Marie Mansour

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this research was to determine a prevalence of degenerative joint disease in our pre-orthodontic adolescent patients age ten through seventeen. The prevalence was assessed according to gender. Severity of DJD was established for each patient and a "red flag" for diagnosis was identified. The purpose was also to establish norms for joint space for patients with and without degenerative joint disease. Correlations to distal condyle position and angle classification were described. 123 consecutive patients, 77 female and 46 male T1 NewTom records were reviewed. Severity of DJD was classified according to none, mild, moderate, and severe. Sagittal …

Bone Formation Using Platelet-Rich Plasma + Allograft: An Experimental Study In Sheep, Edgar Grageda

Loma Linda University Electronic Theses, Dissertations & Projects

Recently Platelet-Rich Plasma has been proven to be an effective regeneration adjunct when combined with autogenous bone in the reconstruction of mandibular defects. However, little is known about the effect of PRP when combined with a bone allograft in the maxillary sinus.

The purpose of this study was to quantitatively evaluate the ability of PRP to enhance bone regeneration in the maxillary sinus of sheep when combined with DFDBA + CCFDBA. Ten sheep were selected for bilateral sinus augmentation DFDBA + CCFDBA + PRP (test) and DFDBA + CCFDBA (control). Five were sacrificed at 3 months and the other five …

Clinical Effectiveness Of A Subperiosteal Anchorage Device, Monica Anne Witte

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this pilot study was to evaluate the clinical efficacy of a subperiosteal anchorage device, the palatal OnPlant™, during orthodontic retraction of protruding anterior teeth in cases requiring maxillary premolar extraction. Seven subjects (5 female, 2 male), ages 13 to 55, were selected for the study. The OnPlant was surgically placed in the mid-palatal region through a well-defined subperiosteal tunnel. Following the manufacturer recommended osseointegration period of four months, the OnPlant was uncovered and attached to the first molars by means of a transpalatal bar. Standard orthodontic treatment then commenced to retract the anterior teeth after the first …

Measured Effects Of Rapid Palatal Expansion On Nasal Cavity Volume Utilizing Cbct, Jon Neal Robinson

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate and predict the expected changes that occur in the nasal cavity volume following rapid palatal expansion. Eighteen subjects (11 female, 7 male), ages 9 to 18, requiring rapid palatal expansion in conjunction with comprehensive orthodontic treatment, were selected for the study. Rapid palatal expansion was accomplished using the standard, banded hyrax appliance. Three-dimensional cone beam computed tomograms using the NewTom 9000™ were acquired before and after expansion. Serial coronal slices of the nasal cavity were made using the QV9000™ software program. The resultant serial images were imported into 3-D Doctor™ for analysis …

Linder-Aronson S Analysis Using Rhinomanometry And Newtom, Noel Moser

Loma Linda University Electronic Theses, Dissertations & Projects

Investigations into the effects of airway patency on craniofacial development are essential to ensure that interceptive orthodontic treatment provides the maximum benefit to the patient. The aims of this study were to (1) compare the size of the nasopharyngeal airway space on lateral cephalometric and 3D volumetric radiographs to determine if volumetric scans can be of greater diagnostic value than a lateral cephalometric film in determining the degree of airway blockage or patency and (2) to examine the correlation between functional airway resistance, as evaluated by rhinomanometry, and radiographic constriction due to nasal turbinate and adenoid size.

Twenty-eight subjects from …

Microleakage Of Various Restorative Materials Used For Preventive Resin Restorations, Jenny Chung Lee

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: This research was designed to compare the microleakage of various restorative materials used for preventive resin restorations and two methods of cavity preparation. The purpose of this study was: (1) to compare microleakage of four different restorative materials using two different type of preparation methods (bur and air particle abrasion) and (2) whether the use of a pit and fissure sealant over the restoration decreases microleakage.

Methods: One hundred and twenty eight, permanent human molars were randomly divided into four groups and restored with four restorative materials. Each group had been randomly divided into two subgroups. The teeth in …

Development Of A Model For Infective Endocarditis Via Intravenous Injection And Tooth Infection Of Rats Using Pathogenic Bacteria, Shahrokh Shabahang

Loma Linda University Electronic Theses, Dissertations & Projects

Historically, focal areas of infection have been linked to a number of systemic ailments. During the early part of the 20th century, patients who were suffering from inexplicable diseases and who were suspected of having infected teeth were referred to the dentist for multiple extraction of their dentition. The discovery of antibiotics provided a false sense of security that the war against microorganisms is no longer a concern for mankind. However, more recently, it has become common belief that increasing numbers of systemic diseases are linked to chronic infections. Recovery of bacteria from representative tissues has led investigators to believe …

A Comparison Of The Semi-Adjustable Articulator And The Virtual Articulator By Centric Relation And Centric Occlusion Contacts, Donald Shane Witherow

Loma Linda University Electronic Theses, Dissertations & Projects

The articulator as we know it has evolved since the late 1700's, however, it has not changed much in function since the 1970's. Our methods of determining contact information i.e., centric stops and pre-maturities also has not changed much beyond that of "carbon paper". With the advent of new computer technologies, dental models are now being placed into the virtual world through variations of image slicing and laser scanning. The purpose of this paper is to determine if the Occlusogram developed by OrthoCad is as accurate as common methods currently used to determine occlusal contacts.

Twenty dental students volunteered to …

Evaluation Of Alveolar And Soft Tissue Changes After Muscular Release Surgery In Patients Undergoing Fixed Orthodontic Therapy, Virginia Bernal

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared pre-treatment to post-treatment changes in patients undergoing fixed orthodontic therapy who have had muscular release surgery. The alveolar and soft tissue changes in the mandible of 128 subjects from a private practice in Northern Italy (74 females and 54 males) were analyzed. In addition, comparisons were made of changes related to age, gender, facial type, and movement of the lower incisor. Lateral cephalograms were analyzed before and after treatment for skeletal, esthetic, and dentoalveolar changes. Photographs were used to assess changes in the soft tissue of the lower anterior region at pretreatment (Tl) versus post-treatment (T2). The …

The Effect Of Thermocycling On Orthodontic Adhesives As Measured By Tensile Bond Strength, James Changwon Choi

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this study was to determine the effect of thermocycling only on the tensile bond strengths of four orthodontic adhesives. With the advent of bonded orthodontic brackets, spontaneous bond failures have been a constant confounding phenomenon. Consequently, numerous studies have been published dealing with the 'bond strength' issue. The focus of these studies is varied, and range from the mode of tooth surface preparation, the type of adhesive, and the type of bracket base design used.

Other studies investigated the effects of different testing methods, such as the traditional shear/peel-type to impact testing. This study was designed to …

Post-Treatment Evaluation Of Isometric Function Of The Elevator Muscles, Margaret Barbara Kowalczyk

Loma Linda University Electronic Theses, Dissertations & Projects

This study mainly examined neuromuscular function, occlusal index, and centric relation-centric occlusion (CR-CO) discrepancy of 23 orthodontically treated patients. Phase I, craniofacial anomalous, and orthognathnic surgery cases were excluded from the study. Record taking was done in 2 sessions: (1) at the time of deband and (2) 3-4 months later. Records taken at each session included facial and intraoral photographs, impressions, CR wax bites, a facebow, and surface EMG (sEMG) recordings.

For the sEMG recordings, electrodes were placed on the upper hyoid, masseter, and anterior temporalis muscles. Subjects were asked to perform numerous tests; these included baseline, clenching to test …

An In Vitro Study Of Plaque Deposition And Its Comparative Effect On Bond Strength, Debra L. Finch Cook

Loma Linda University Electronic Theses, Dissertations & Projects

Treatment with fixed orthodontic appliances can change the environment in the oral cavity by creating stagnant areas that facilitate bacterial colonization and substance retention. The purpose of this study was to examine in vitro plaque formation associated with bonded orthodontic appliances and how this could affect bonding strengths.

Ortho Concise and Transbond XT were the composite resin materials used in this study. Mandibular incisor metal brackets were bonded to bovine mandibular anterior teeth. Each composite resin was studied in two groups: plaque growth and without plaque growth, and their bond strengths were compared at time intervals of 3,45, and 180 …

A New Soft Tissue Analysis : To Establish Facial Esthetic Norms In Young Adult Females, Anne Béress

Loma Linda University Electronic Theses, Dissertations & Projects

Two hundred and fifty-five articles, books, and masters theses were reviewed for the most frequently applied soft tissue measurements in the literature in order to develop a new soft tissue analysis computer program that includes established soft tissue measurements and the newly developed globe analysis. A meta analysis of 20 normal occlusion studies, was performed to obtain mean values and standard deviations to form a large sample size. Inclusion criteria for articles in the meta analysis were normal occlusion, no orthodontic treatment, pleasing faces, statement on age, race, and lip position of the population. For the lateral view, angular and …

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 …

The Experimental Verification Of The Efficacy Of Finite Element Modeling To Dental Implant Systems, Thomas D. Baiamonte

Loma Linda University Electronic Theses, Dissertations & Projects

The finite element method has previously been used to evaluate the stress distribution surrounding the dental implant to bone interface. However, prior finite element analysis models used have not been validated for the bone to implant interface. The objective of this study is to investigate whether the current Ansys finite element analysis model is an accurate biological representation of the observed clinical conditions. This will be accomplished by comparing data obtained experimentally of stress versus strain and the three dimensional computer generated finite element model.

The results indicate finite element method using the Ansys program for modeling is in agreement …

Ability Of Cylindrical Root Form Implants To Withstand Controlled Lateral Forces, Silvio Emanuelli

Loma Linda University Electronic Theses, Dissertations & Projects

The ability of root form implants to withstand lateral forces has been investigated in animal model. Two new techniques for quantification of forces generated by a loading device have been developed and tested. The strain gages bonded to the loading device were calibrated either intraorally by a micro load cell, or in laboratory by Instrom Machine.

Preliminary results indicate that laterally applied continuous forces up to 6,000 grams do not elicit failure of root form implants.

Facial Typing Methods : A Comparative Study, James A. Grabow

Loma Linda University Electronic Theses, Dissertations & Projects

Facial typing methods are used to determine to which of three basic facial pattern categories an individual patient belongs. These three categories are mesofacial, brachyfacial, and dolichofacial. It is important to establish the correct facial type because the reaction to treatment mechanics and the stability of the denture is dependent upon the analysis of the facial patterns. The purpose of this paper was to show a comparative study of facial typing classification methods used on 100 patients (47 boys and 53 girls). The eight different methods used were as follows: Bioprogressive, Ricketts LLU1, LLU2, QuickCeph™, Jarabak, Facial-Mandibular Index, and Steiner. …

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. …

Marginal Periodontium Changes In The Monkey (Macaca Nemestrina) Following Incisor Repositioning From A Mechanically Positioned Labioversion, Gary Engelking

Loma Linda University Electronic Theses, Dissertations & Projects

The anterior teeth of five adult pigtail monkeys were moved lingually to correct a previously induced labioversion. These teeth were retained in their more normal arch positions for five months, after which clinical and histologic measurements were made of the periodontium. The untreated cuspids served as controls. Measurements were made to record changes in the gingival margin, the mucogingival junction, the width of keratinized gingiva and the marginal bone level relative to a fixed point on the tooth crowns. Oxytetracycline was administered three times to label areas of osteogenesis in the periodontium.

The incisors were retracted a mean distance of …

Evaluation Of A Precision Filing Test For Predicting Dental Technic Performance, Douglass Roberts

Loma Linda University Electronic Theses, Dissertations & Projects

A precision filing test involving the reduction of a steel cylinder to a perfect cube with the use of a hand file and bench vise was devised as a diagnostic tool for the early detection of freshman students having technic difficulties. The test was administered to 188 freshman dental students in three classes at Loma Linda University, School of Dentistry. Subjective and objective scores were then statistically compared with subsequent technic and clinic grades of the students. The simple linear correlations between the predictor test variable and criterion grades were statistically significant for one class and for the combined classes …

The Uses Of Pins For Retention In Restorative Dentistry : An Independent Learning Program, Ali M. Asad

Loma Linda University Electronic Theses, Dissertations & Projects

Although pins have been used since the 1800's for retention of dental restorations, their widespread use had been limited because supporting techniques such as impression, die materials, better handpieces and drills have only been perfected in the last two decades.

The pin technique allows for greater retention of restorative materials which otherwise might require considerable reduction of sound tooth substance; this is particularly paramount when insufficient coronal tooth structure is present. Also, the placing of pins in divergent directions gives excellent retention. Pin-retained castings reduce the need for deep cavity preparation in some cases.

Pins are useful in stabilizing hypermobile …

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 …

Pins In A Composite : Their Effects On The Strength Of The Material, Milton Latoni-Camarena

Loma Linda University Electronic Theses, Dissertations & Projects

The influence of pins on the compression and tensile strength of a composite resin was measured.

Compression strength was measured in cylindrical samples 8 mm long and 4 mm in diameter, using different size threaded stainless steel pins. The tensile strength was determined by compression along the diameter of cylindrical samples containing different sizes and orientations of threaded stainless steel pins.

The conventional dumbbell tensile strength was measured by pulling the mounted specimens in the direction of their long axis, using non-threaded pins.

These tests demonstrated that the compressive strength of the composite was increased 10 percent when the large …

Measurement Of The Force Of The External Pterygoid Muscles, Hajime Suya

Loma Linda University Electronic Theses, Dissertations & Projects

Much research has been done to determine closure forces of patients. This study was designed to determine the effect of certain variables on the maximum protrusive force of patients.

Custom mandibular clutches were fabricated out of blue tray resin for each patient. A clutch adaptor was fastened to the clutch to secure the weight testing apparatus. Maximum protrusive forces were recorded for each patient when the force paralleled the Frankfurt line and the angle of the eminence. This testing was accomplished with and without the use of a maxillary clutch, designed to allow the closure muscles to brace the mandibular …