Dentistry Commons^™

A Cephalometric Study Of The Class Ii Correction Effects Of The Eureka Spring, Ernest L. Stromeyer

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of the Eureka Spring appliance, was investigated on 37 consecutively treated, non compliant, bilateral Class II malocclusions, requiring at least 3 mm or more of additional molar correction. The mean pretreatment age of this sample was 13.9 years. All patients were treated by a single clinician utilizing the Eureka Spring. Lateral cephalographs were taken at start of orthodontic treatment (T1), at insertion of Eureka Springs (T2), and at removal of the Eureka Springs (T3). The average treatment interval between T2 and T3 was 4 months. Class II correction occurred almost entirely by dentoalveolar movement, 33% in the maxilla …

A Pilot Study On The Short Term Effects Of The Herbst Appliance On The Glenoid Fossa, David A. Bennion

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this pilot study was to evaluate the initial effects of the Herbst appliance and determine through the use of common cephalometric radiographs that were optically enhanced and then digitally reproduced, if fossa migration is taking place. Fourteen, (6 male, 8 female), growing patients were treated by the same clinician for the correction of a Class II malocclusion using a modified Herbst appliance. Pretreatment (T₁) standard lateral cephalometric radiographs and post Herbst treatment (T_H) optically enhanced lateral cephalometric radiographs were taken. All radiographs were digitally captured and reproduced so 6 linear and 1 area …

An Investigation Of The Divine Proportion In Varying Facial Types, Gender And Age Groups, Chris A. Coleman

Loma Linda University Electronic Theses, Dissertations & Projects

This retrospective study evaluated the 26 cephalometric measurements which comprise 13 ratios that were purposed by Robert M. Ricketts to be Divine Proportions. The hypothesis that was tested in this study was one that stated that these 13 ratios were not only Divine Proportions, but were constant in all facial types, in both genders and in all stages of growth. In an effort to test this hypothesis, cephalographs were chosen at random from the files of Dr. Ruel Bench, which are currently housed in the Ricketts Research Library at Loma Linda University. Each film tracing was reviewed for accuracy and …

A Study Of Craniofacial Growth In Infant Heart Transplant Recipients Receiving Cyclosporine, David G. Niles

Loma Linda University Electronic Theses, Dissertations & Projects

Cyclosporine is an effective immunosuppressive drug that has found widespread application in organ transplantation. However, a few studies have implicated cyclosporine as adversely affecting craniofacial growth in the pediatric population. The purpose of this study was to evaluate the possible untoward effects of cyclosporine long-term on craniofacial growth in a group of infant heart transplantation recipients. A prospective group (n=28) of eighteen Caucasian children (9 female and 9 male, ages 4-10 years) and ten Hispanic children (3 female and 7 male, ages 4-10 years) were evaluated. None of the subjects had undergone orthodontic therapy. All subjects had heart transplantation before …

A Comparative Study Of The Permanent Deformation Of Aesthetic Polymer Brackets, Samar Bou Assi

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to Investigate and compare the plastic or permanent deformation of different commercially available aesthetic polymer brackets (American, Ormco, GAC and RMO). It also examined the effect of tying the bracket wings with a wire ligature as well as the effect of thermocycling on the permanent deformation of these brackets.

Seven brackets of each type were tested In each of the three following conditions; group 1; tied with a wire ligature and loaded, group 2; thermocycled and loaded, and group 3: loaded only, with a total of 84 brackets tested. Each bracket was bonded to …

The Relationship Of Tooth Size And Arch Form To Arch Depth, Harold C. Avila

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the relationship of arch form and tooth size to arch depth measurements of study models (Casts) and their respective lateral cephalometric radiographs (Radiographs) in a population of patients treated to an acceptable occlusion without extraction. One hundred and twenty casts were divided into three tooth size classes within each of four arch form categories. Results showed there was a statistically significant change in the arch depth measurement when tooth size was varied. There was no statistically significant change in the arch depth measurement when arch form was varied. The results showed greater …

Change In Bracket Bond Strength And Enamel Calcium : Due To Repeated Bonding With Conventional And Resinomer Glass Ionomer Cements, David L. Wilkinson

Loma Linda University Electronic Theses, Dissertations & Projects

Glass ionomers chemically and mechanically bond to enamel. Repeated bonding may deplete calcium in enamel and reduce the bond strength. Seventy-five non-carious molars were randomly divided into three equal groups and metal brackets were bonded with either Ketac-Cem, Photac-Bond, or Fuji Ortho LC. The samples were stored in 100% humidity at 37° C for 7 days then shear/peel tested with an Instron machine. New brackets were repeatedly cemented with the same cement to the same tooth and shear/peel tested a total of five times. After each shear/peel test the tooth with the mean bond strength from each cement was set …

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 …

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 …

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 …

In Vitro Plaque Formation On Orthodontic Resin Sealants, Leland W. Pack

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to examine in vitro plaque formation on sealant coated enamel. The plaque growth on different types of sealants placed on enamel was compared to each other and to an unsealed enamel control. The antimicrobial properties of sealants were also studied.

Sealant coated bovine enamel disks were immersed in a S. mutans culture medium for four days. The amount of bacterial plaque formation was quantified by removing the deposit, suspending it in solution with subsequent serial dilution. Aliquots of the dilutions were then spread on blood agar plates and incubated for 48 hours. The number …

The Effect Of Guidor™ And Hop-1 On Hard Tissue Healing : Following Periradicular Surgery In Cats, Hugh Maguire

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the effects of the resorbable membrane Guidor™ and the osteogenic protein hOP-1 on hard tissue healing following periradicular surgery in cats.

Surgical endodontic therapy was performed on the maxillary canine teeth of twelve cats. After orthograde root canal therapy, flap reflection, osteotomy, resection of the root end, root end cavity preparation and the placement of a root end filling, eight of the surgical sites were treated with Guidor™ and eight with hOP-1. The remaining eight sites received no further treatment and served as controls.

The animals were sacrificed at twelve weeks following …

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 …

Treatment Effects Of The Edgewise Bioprogressive Herbst Appliance, Bernard C. Chang

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of the Edgewise Bioprogressive Herbst appliance, as described by Dr. Terry Dischinger, was investigated on 24 Class II, Division 1 malocclusions. Mean pretreatment age of this sample was 11.2 months. All patients were treated by Dischinger with a Bioprogressive Herbst appliance. Lateral cephalographs taken before, after Herbst appliance therapy, and after edgewise treatment were traced, then digitized into Quick Ceph™. Measurements were computed by the computer software. The following results were found: 1) Average treatment time was 9 months. 2) An overcorrected Class I relationship was achieved. 3) Class II malocclusion was corrected by 4.5 mm skeletal alteration …

The Accuracy Of Computer Video Imaging Prediction : Just Prior To Surgical Mandibular Advancement/Genioplasty Orthognathic Cases, Jason T. Chiakowsky

Loma Linda University Electronic Theses, Dissertations & Projects

The accuracy of the computer video imaging treatment prediction was investigated using Quick Ceph Image.™ Thirty one surgical mandibular advancement/genioplasty orthognathic cases were examined to determine if the soft tissue profile prediction was representative of the actual result. All patients were over the age of 18. Lateral cephalographs and slides were taken immediately pre-surgically, and six months post-surgically. The slides were duplicated into 4X6 photographs. The cephalographs were digitized and the photographs captured by video on the Quick Ceph Image software program. A line drawing and computer video image treatment prediction were generated using the actual surgical change that had …

Mutagenecity Of Formocresol, Glutaraldehyde, Ferric Sulfate And Aluminum Chloride : Materials Used In Therapeutic Pulpotomies, Adolfo Barrera

Loma Linda University Electronic Theses, Dissertations & Projects

Ferric sulfate (Astringedent) and aluminum chloride (Hemodent) have been proposed as possible medicaments for use in primary teeth for therapeutic pulpotomies.

There is little information in the literature about the biologic properties of these medicaments.

The purpose of this study was to evaluate the mutagenic response of the ferric sulfate and aluminum chloride and compare them with glutaraldehyde (1.5%, 1% and 0.5% concentration) and formocresol (2%, 0.75%, 0.01% and 0.005% concentration). TA98 and TA1535 strain were used in the Ames test to assess mutagenecity. Neither ferric sulfate nor aluminum chloride exhibited mutagenic potential, in comparison with glutaraldehyde and formocresol, which …

Current Theories On The Cell Biology Associated With Tooth Movement, Mohamadreza Yazdi

Loma Linda University Electronic Theses, Dissertations & Projects

This article discusses the current information on the mechanism of the biological signaling that takes place to bring about orthodontic tooth movement.

Currently, there are two general theories as to how orthodontic mechanical force is translated to biologically meaningful signals for the cells of the periodontium. These include a cellular-humoral response and a bioelectric response.

There are various mechanisms utilized by the cells of the periodontium to bring about the cellular-humoral response. These include: The activation of the cells of the immune system to synthesize and release specific chemicals (cytokines) which affect cell function, direct effects of mechanical force on …

Mandibular Asymmetry In Unilateral Class Ii Malocclusion : A Cephalometric Study, Raed Z. Moussa

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to evaluate skeletal and dental asymmetry in unilateral class II malocclusion. A study group of 25 unilateral subdivision patients was compared to 25 class I malocclusion patients serving as the control group. Submento-vertical and frontal radiographs were used for the evaluation. Symmetry was evaluated by comparing measurements between right and left sides for both groups and matching the middle points with the midsagittal axis. Statistical paired and simple t-test were used to evaluate the difference between the two sides for both groups. The measurements showed no significant skeletal and dental asymmetries except for three …

An Immediate Implant Stability And Pull-Out Study Comparing Two Different Surgical Techniques : Conventional Drilling Versus Trabecular Compaction : A Pilot Study, Yong Chang Choi

Loma Linda University Electronic Theses, Dissertations & Projects

Poor bone quality at an implant site and the lack of initial implant immobilization are considered the two main factors for first stage implant failure. Modalities are needed to improve the initial stability of implants in poor bone quality situations. The purpose of this study was to compare the immediate implant stability and the pull-out force of implants placed in fresh frozen human alveolar jaw bones by two different surgical techniques: 1) a conventional drilling technique and 2) a trabecular compaction technique. The initial lateral stability (assessed by Periotest values, PTVs), the uniaxial pull-out force (measured by Instron machine) and …

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) …

Space Closure Efficiency With Modified Ceramic Brackets : A Comparative Study, Kirk A. Specht

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine if the rate of extraction site closure was determined by the type of ceramic bracket used. A new ceramic bracket with a metal archwire slot was compared with a conventional ceramic bracket. Twenty patients were randomly assigned the metal slot ceramic bracket and conventional ceramic to one half of their maxillary arch respectively. The distribution was even left and right.

Retraction was started and completed on an 0.016" stainless steel round continuous archwire. One hundred gram sentalloy springs provided a uniform retraction force and were reactivated every four weeks to maintain a …

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 …

The Rotations Of Maxillary Molars, Mandibular Molars, And Maxillary First Premolars In Acceptable Occlusions, G. Kristian Hansen

Loma Linda University Electronic Theses, Dissertations & Projects

The rotation of the maxillary molars is considered important in the orthodontic treatment of malocclusions. In this study a computer analysis program was developed to examine the rotations of maxillary molars, mandibular molars, and maxillary first premolars in casts of permanent dentitions with acceptable occlusions. Ninety three sets of untreated "acceptable occlusion" models from the collection of the Foundation for Orthodontic Research (FOR) were scanned on a flat bed scanner at 600 dots per inch (dpi). The images were analyzed using custom software on a computer. Measurements were made by relating maxillary first permanent molars to the midline, the archform, …

A Comparison Of Retentive Strengths Of Two Types Of Inner Surface Treatments Of Orthodontic Bands, Jean M. Rathbun

Loma Linda University Electronic Theses, Dissertations & Projects

Band failure during orthodontic treatment results in a potential for decalcification and/or caries and may cause a prolonged treatment time. An increase in the bond strength at the cement/band interface would likely decrease clinical band failure. Sand-blasting and photo-etching have been suggested to improve this bond.

This study investigated the retentive strengths of untreated orthodontic bands, sand-blasted bands and photo-etched bands when cemented with glass polyalkenoate cement on extracted human molars. The sand-blasted bands and photo-etched bands were both found to have significantly stronger bond strengths (p

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 Effects Of Rapid Palatal Expansion Therapy On The Periodontal Tissues Of The Central Incisors, Richard Gutierrez

Loma Linda University Electronic Theses, Dissertations & Projects

The periodontal structures around the maxillary central incisors in thirty-nine post-orthodontically treated patients, twenty-five of these patients had experienced Rapid Palatal Expansion (RPE), were examined to determine the periodontal consequences associated with two ways of managing the resultant diastema. In fourteen patients the diastema closure was assisted by elastomeric chain and in eleven patients the diastema closure was not assisted. Fourteen non-RPE orthodontically treated patients served as controls. Height of attached gingiva, gingival sulcus depth, attachment level, and alveolar bone level were recorded. One examiner, using calibrated techniques, performed all the measurements. The RPE groups and the control group all …

Plastic Deformation Of A Polycarbonate Bracket : Utilizing A New Testing Apparatus, Terri L. Alfred

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to investigate the plastic (permanent) deformation of a polycarbonate bracket (Miura, RMO) under the following different conditions: (1) untreated, (2) immersed in 37°C-water for 120 days, and (3) immersed in 60°C-water for 24 hours. Ten brackets for each condition were tested, with a total of 30 brackets tested. Each bracket was bonded to a metal mesh pad which was tack welded to a solid stainless steel ring. The assembly was placed under a loading frame. This loading frame removes variables such as bond adhesive strengths, distortion of a wire used to deform the bracket …

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 …

A Pilot Study Comparing The Forces Applied : Using A Chin Cup And Three Types Of Protraction Headgear, Daniel Miles Beisiegel

Loma Linda University Electronic Theses, Dissertations & Projects

A pilot study comparing force distributions of a chin cup, the Great Lakes reverse pull headgear (RPHG), Ormco's adjustable dynamic RPHG, and Grummons RPHG was done. A skull from a 69 year old female which demonstrated a Class III malocclusion was used to perform the tests of force. Forces applied to and generated on the skull were measured using a water-filled balloon system. This method was tested and found to be reliable and accurate.

Repeated measurements of force were recorded for each of the areas of stress (forehead, cheeks, chin, and condyles, as well as the posterior and superior portions …

Healing Potential Of Osteotomies Of The Nasal Sinus In The Dog, Roderick W. Tataryn

Loma Linda University Electronic Theses, Dissertations & Projects

Maxillary sinus osteotomy is sometimes indicated for transantral surgical approaches to palatal roots of maxillary molars. A search of the literature showed an absence of any report on the healing potential of such defects. The purpose of this study was to determine histologically the reparative process of the nasal sinus of dogs following small and large surgical antral perforations. After anesthetizing six beagle dogs, full thickness periosteal flaps were raised overlying the maxillary buccal cortical plates. A 5x5 mm diameter perforation was created with a trephine bur above the second maxillary premolar on one side of each animal. On the …