Medicine and Health Sciences Commons^™

Force Comparison Of Rotational Tooth Movements For Loop-Design And Traditional Aligners, Robert Olsen

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction

This study aimed to evaluate the force (F) and torque (Tq) exerted on a rotated canine and molar tooth by two different aligner systems. An ArchForm loop clear aligner (AFL) was compared to a traditional clear aligner (T) with the force (F) and torque (Tq) compared. A reduction in F and Tq with AFL aligners could possibly decrease the incidence of Orthodontic Root Resorption (ORR), while also creating more effective forces for tooth movement.

Materials and Methods

Two types of T aligners varying by material thickness were compared to two types of AFL aligners varying by loop width. All …

Maxillary Central Incisor Rr In Hispanic And Non-Hispanic White Patients With Rme, Madison Healy

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Apical root resorption is one of the most common adverse effects of orthodontic treatment. Forces used during orthodontic tooth movement can cause permanent loss of apical surfaces of teeth and although most reported cases of root resorption are asymptomatic, the process is irreversible and often unpredictable. Thus, it is of clinical interest to investigate which patients may be at greatest risk.

Purpose: This study utilized Cone Beam Computed Tomography (CBCT) to evaluate whether rapid maxillary expansion (RME) in Hispanic patients increased the severity of orthodontically induced apical root resorption.

Materials and Methods: Pre-treatment (T1) and post-treatment …

Titanium Particles Within Mucosa During Non-Surgical Implant Debridement, Holvin Louie

Loma Linda University Electronic Theses, Dissertations & Projects

Titanium implants affected by peri-implantitis lesions are often treated non-surgically with various instruments, which may produce titanium particles that can become lodged within the peri-implant mucosa. Thus, a foreign body reaction may ensue. The aim is to assess the embedment of titanium particles into soft tissues from titanium implants via a stainless-steel ultrasonic scaler (SSU) versus a titanium hand scaler (TH). Sand-blasted, large grit, acid-etched surface-treated titanium implants were implanted into pig legs after creating peri-implantitis defects. Each implant was subjected to only one instrument type. Sequential strokes were conducted followed by thorough irrigation with sterile water. Soft tissue curettage …

A Study In Fresh Human Cadaver Heads Examining The Incidence Of Maxillary Sinus Membrane Perforation During Crestal Sinus Elevation Comparing Osteotomes To Osseodensification Drills., Thaer Alqadoumi

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Crestal sinus membrane elevation technique is a surgical procedure that helps gain vertical bone volume when there is a pneumatization of the maxillary sinus. Due to some visual limitations inherent to the procedure, the potential for maxillary sinus membrane perforations and subsequent complications exists. A crestal sinus lift using osseodensification drills has been used lately but there are not many studies to support the protocol. The primary aim of the study is to evaluate the incidence of sinus membrane perforation during Osseodensification compared to the incidence of bone added crestal sinus elevation using osteotomes (BAOSFE). The secondary aim …

Effect Of Splinting Implant Scan Bodies Intraorally On The Trueness Of Complete Arch Digital Impressions: A Clinical Study, Kawther Mahmoud Ali

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The purpose of this study was to investigate the effect of splinting scan bodies intraorally on the trueness and scan time of implant digital impressions of the edentulous arch.

Materials and Methods: Nineteen edentulous jaws undergoing fixed complete denture treatment with a minimum of 4 implants were selected for this study. Verified master casts of the patients’ edentulous jaws were scanned with a desktop laboratory scanner and scan bodies to obtain a reference (control) scan for each patient. Intraoral scan bodies were hand tightened on all the implants in the edentulous arch and an intraoral scan was …

Evaluating The Treatment Effectiveness And Efficiency Of The Df2 Protocol Using Invisalign® For Treatment Of Class Ii Malocclusion: A Retrospective Comparison Study, Bryan J. Otis

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: This retrospective study evaluated the treatment effectiveness and efficiency of the DF2 protocol for correction of class II malocclusions in comparison to conventional protocol using Invisalign®.

Materials and Methods: Clinical and cephalometric data of patients that were treated for class II malocclusion between July 30, 2014 and July 22, 2021 were reviewed and selected. The selected patients were matched for age, sex, and treatment complexity and divided into two groups: Group 1 (G1) —DF2 protocol and Group 2 (G2)—conventional class II Invisalign®. Clinical variables to represent the skeletal and dentoalveolar changes during treatment were assessed using pre-treatment (T1) …

A Comparison Of The Area Of The Internal Nasal Valve In Cbct And Mri, Chantelle Ghiam

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: This study compared the agreement between whole head Cone-Beam Computed Tomography (CBCT) and 3T Magnetic Resonance Imaging (MRI) methods to assess the cross-sectional area of the internal nasal valve.

Methods: Thirteen human subjects (mean age 15y11m) were used in this study. All scans were preformed [sic] within two weeks of one another. CBCT images were made with an 18x16 inch field of view, exposure time of 5.4 s, and resolution of 0.3x0.3x0.3 mm. 3T MR images were captured as contiguous sagittal images of the whole head with a T1-weighted 3D imaging sequence (Magnetization Prepared Rapid Acquisition by …

Attitudes And Understanding Of Orthodontic Treatment Using Comic Vs. Text Format, Darron Miya

Loma Linda University Electronic Theses, Dissertations & Projects

Objectives: To examine adolescent patient attitudes and understanding of basic orthodontic treatment information presented in either comic book format or plain text.

Methods: This study involved subjects undergoing orthodontic treatment at the Loma Linda University Graduate Orthodontic Clinic. Subjects were randomly assigned to two groups: Group 1 subjects received an orthodontic comic book to read, while Group 2 subjects received a plain text information sheet containing the same pertinent information as Group 1. All subjects completed an identical survey regarding the material they read. Statistical analysis consisted of a chi-square test at α = 0.05 to determine potential …

Comparison Of Heat Generated During Twist Drilling Protocol By Guided And Non-Guided Implant Surgery, Joshua Lee

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Guided implant surgery is becoming more prevalent among clinicians and is crucial for cases in which there are concerns about the proximity of the implant to vital anatomical structures, esthetic concerns, and the amount/quality of bone available. Surgical guides help with the angulation and positioning of the implant through the use of a CBCT scan and digital intraoral impression. However, there are some drawbacks with guided surgery. Heat that is generated during the osteotomy is one of the issues that has been of concern. The guide acts as a shield against the water irrigation from reaching the osteotomy …

A Comparison Of Heat Generated Between Carbide And Diamond Bur During Implantoplasty, Bryce Chun

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: This study was conducted to evaluate heat generated during the implantoplasty procedure by comparing the heat generated using either a carbide or diamond round bur. Materials and Methods: Bovine ribs were selected as the osseous model for this study. Changes in temperature were measured using a digital thermometer (Extech SDL200 four channel thermometer, Extech instruments, Melrose MA). Ther k-thermocouples were positioned within the implant screw access, apex of the implant, and crestal bone adjacent to the implant and ambient air. 5 bovine rib bone blocks were prepared by place 5 cylindrical titanium grade 5 alloy large grit sand blasted …

Synthesis And Characterization Of Hemocompatible Antibiotic Nanoparticles, Elvin Muhindo Walemba

Loma Linda University Electronic Theses, Dissertations & Projects

Porphyromonas gingivalis is a causative agent of periodontal disease and a risk factor for cardiovascular disease. Novel treatment of periodontal disease using nanomaterials can supplement or replace the use of antibiotics and mechanical debridement. Nanomaterials can be optimized for effectiveness and specificity and minimum toxicity. Synthesized Ag nanoparticles stabilized in Pluronic F127 were used to produce bimetallic core/shell Ag/Au nanoparticles with optimized Ag+ release and reduced toxicity. We tested the F127-stabilized nanoparticles for their antimicrobial activity and hemocompatibility in planktonic bacteria and citrated whole blood, respectively. Both Ag and Ag/Au bimetallic nanoparticles inhibited P. gingivalis W83 growth. We then evaluated …

Ratio Of Rme Appliance Expansion To Increase In Arch Perimeter Using Cbct Imaging, Evan Agnetta

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: This study measured CBCT images to determine if a consistent ratio exists between the quantifiable number of millimeters a cemented rapid palatal expansion appliance is opened and the subsequent increase in the arch perimeter obtained due to lateral expansion of the arch.

Methods: The following measurements: arch perimeter, arch width at first molars, first bicuspids, appliance length, as well as arch depth; were taken from CBCT images of patients who had completed RME therapy. These were obtained both before and after maxillary palatal expansion therapy using a fixed rapid palatal expander. Correlations were calculated for each of …

In-Vitro Comparison Of Retention Among Contemporary And Conventional Post-And- Cores, Hatem Alqarni

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: Computer-aided design/computer-aided manufacturing (CAD/CAM) technology is gaining popularity in dentistry, and more recently, used to fabricate custom post-andcores (PC) for endodontically treated teeth. The purpose of this study was 1) to evaluate the overall retention of conventional cast gold post-and-cores compared to CAD/CAM fabricated printed, milled titanium post-and-core and milled zirconia post-and-cores based on load, time of dislodgement and 2) to evaluate the mode of failure of the post-and-cores.

Materials and Methods: A maxillary central incisor was selected. Root canal treatment was performed, and acrylic resin pattern was used to fabricate post-and-core. A total of 80 post-and-cores (20 …

Measurements Of The Pharyngeal Airway Using Whole Head 3t Mri And Cbct, Victoria Geren

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: This study compared pharyngeal airway measurements (volume, linear, area) made using whole head Cone-Beam Computed Tomography (CBCT) and 3T Magnetic Resonance Imaging (MRI) methods.

Methods: Eleven subjects (mean age 15y11m) received whole head CBCT (NewTom5G, AFP Imaging, USA) and 3T MRI (Siemens Medical Solutions, DE). Each subject received both scans within a one-month period of time. CBCT images were made with an 18x16 inch field of view, exposure time of 5.4s, and resolution of 0.3x0.3x0.3mm. 3T MR images were captured as contiguous sagittal images of the whole head with a T1- weighted 3D imaging sequence (Magnetization Prepared …

Clinical Effects Of Oral Hygiene Instruction Via Texting In Orthodontic Patients, Jessica Liu

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: This randomized controlled study quantitatively investigated whether providing oral hygiene instruction (OHI), through texting images and videos, affected oral hygiene status in orthodontic patients.

Materials and Methods: Sixty patients between 13-21 years of age, with visible plaque and used a smart phone, were recruited from the Graduate Orthodontic Clinic at Loma Linda University. Once recruited (T1), an initial survey was completed, MBI and OPI were recorded, and OHI was given. Subjects were randomly distributed into either a control or experimental group. The experimental group received OHI texts weekly, whereas the control group did not. After 3 months …

Comparison Of Maxillary Sinus Dimensions And Volumes On Cbct And 3t Mr Images, Cara Hodgson

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: This study compared the height, width, length, and volume of the maxillary sinus in Magnetic Resonance Imaging (MRI) and Cone-Beam Computed Tomography (CBCT).

Methods: Eleven human subjects participated in the study (mean age of 14y7m). One CBCT scan and one MRI scan were performed on each patient. CBCT images were captured with an 18 x16 inch field of view that covered the whole head. Contiguous sagittal MR images of the whole head were produced using a 3.0T imaging system with a T1-weighted 3D imaging sequence and isotropic resolution of 1.0 x1.0 x1.0 mm. Images were imported as …

Accuracy Of Surface Area And Volume Measurements Of Teeth Determined From Cbct, Joseph Hourany

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: This study compared surface area and volume measurements made from 3D scans of physical teeth and segmented teeth taken from Cone-Beam Computed Tomography (CBCT) scans of a cadaver. Methods: A cadaver specimen was imaged by CBCT and all the teeth were subsequently extracted and cleaned of any tissue. Of all the extracted teeth, sixteen single-rooted teeth were included in this study. The extracted teeth were scanned with a 3M True Definition 3rd Generation intraoral scanner (3M, ESPE) to generate a stereolithography (STL) file to serve as the control for this study and their surface area and volume measurements as …

Accuracy Of Intraoral Scanners With Different Total Occlusal Convergence Angles: An In-Vitro Study, Brittany M. Pang

Loma Linda University Electronic Theses, Dissertations & Projects

Digital intraoral imaging has become more utilized in contemporary dental practice. This is performed using an intraoral scanner and it can be used as an alternative to making conventional impressions when indicated. This technology has many advantages, such as decreasing the number of appointments by eliminating traditional techniques, along with a reduction of laboratory time and improved patient comfort. The accuracy of intraoral scanners is currently being assessed in various aspects. To our knowledge, no study has yet addressed the accuracy of intraoral scanners in regards to total occlusal convergence (TOC) of complete coverage of anterior and posterior preparations in …

Complications Associated With Mandibular Fixed Complete Arch Prostheses Based On Implant Distribution, Shivani Karre

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The objective of this study is to compare incidence and type of complications associated with mandibular implant supported fixed complete arch prostheses based on implant distribution. Material and Methods: Patient Selection: The retrospective study included data collected from axiUm CE Version 6.05.01.2007 from year July 2007 to July 2018 for all patients treated with mandibular implant supported fixed complete arch prostheses (MISFCPs) at Loma Linda University School of Dentistry (LLUSD). One hundred and twenty seven patient’s charts were reviewed to document implant distribution and incidences of complications associated with each implant distribution groups on MISFCPs. Complications like screw …

Comparison Of Antimicrobial Agents Ozonated Olive Oil And Chlorhexidine Gluconate - An In Vitro Study, Amelia David

Loma Linda University Electronic Theses, Dissertations & Projects

Aim: This study was aimed to compare the antibacterial effect of a commercially available OzOO with CHX 0.12% oral rinse solution against periodontal pathogens F. alocis, Aa, S. mitis, and S. mutans using a disk diffusion method.

Materials and Methods:

The antimicrobial agents OzOO and 0.12% CHX were impregnated onto sterile discs and placed onto bacterial cultures of F.alocis, Aa, S.mutans, and S.mitis to evaluate their antimicrobial activity by the disk diffusion susceptibility method. The bacterial growth inhibition zone surrounding each disc was measured in millimeters of diameter with calipers to assess the antimicrobial activity of each agent. …

Effect Of Centric Interference On Canine Tooth Wear, Andrey Gaiduchik

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The aim of this study was to determine the long term effect of a centric interference on canine tooth wear (CTW) and on centric occlusion (CO) and maximal intercuspation (MIP) variance. Materials and Methods: Thirty subjects, 11 males and 19 females, were selected based on inclusion and exclusion criteria. Changes in enamel volume were studied between the end of orthodontic treatment (T2) and at least seven years post treatment (T4). All models were scanned using a high resolution desktop scanner, (OrthoInsight 3D Scanner™, MotionView LLC). T4 models were articulated using a Panadent® Articulator and evaluated for dental interferences and …

Estimating Root Volumes By Limited Segmentation: A Volumetric Analysis Of Cbct And Micro-Ct Data, Theresa C. Baldwin

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: The increased dimensional accuracy of images provided by cone beam computed tomography (CBCT) scans allows for more in-depth diagnosis and treatment planning. Expedient interpolation of segmented data that provides clinically acceptable results will encourage clinicians to frequently use CBCT images for clinical/radiographic evaluation. Some of these applications include, quantification of root resorption, determination of force required for specific tooth movements, and customized appliances. Purpose: The study had two purposes. The first was to compare the accuracy of digital tooth volumes acquired from CBCT to the gold standard, micro-computed tomography (micro-CT). The second was to determine the effect of axial …

The Wear Of Acrylic Resin And Composite Resin Teeth Against Polished And Glazed Zirconia, Abdulkareem Alshehri

Loma Linda University Electronic Theses, Dissertations & Projects

Background: Excessive wear for the occlusal surfaces of teeth results in decreased masticatory efficiency, poor esthetics and leads to reduced the occlusal vertical dimension which could lead to the development of temporomandibular disorders, consequently, further compromise function. Very few studies have been performed on the wear resistance of zirconia against artificial denture teeth and human enamel. Aim: The purpose of this study was to investigate the influence of polished zirconia (PZ) and glazed zirconia (GZ) on the 2-body wear resistance (vertical substance loss) of seven commercially available denture teeth made of different resins. Material and Method: Eight groups (n=10) of …

In-Vitro Evaluation Of Accuracy Of Conventional And Cad/Cam Removable Partial Denture Frameworks, Pooya Soltanzadeh

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: Computer-aided design/computer-aided manufacturing (CAD/CAM) technology is gaining popularity in dentistry, and more recently, to fabricate removable partial dentures (RPD). The purpose of this study was 1) to evaluate the overall accuracy and fit of conventional versus CAD/CAM fabricated printed RPD frameworks based on STL data analysis, and 2) to evaluate the accuracy and fit of each component of the RPD framework. Materials and Methods: A maxillary metal framework was designed for a Kennedy class III modification I situation. The master model was scanned and used to compare the fit and accuracy of the RPD frameworks. A total of 40 …

Reliability And Accuracy Of A Novel Photogrammetric Orthodontic Monitoring System, Vahe Ohanesian

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: This study quantitatively investigated the reliability and accuracy of Dental Monitoring’sTM proprietary orthodontic tracking system in comparison to an established reference. Materials and Methods: Intraoral scans (True Definition Scanner, 3MTM) and video scans (iPhone 7, AppleTM) were taken of 30 subjects undergoing comprehensive orthodontic treatment at Loma Linda University’s Graduate Orthodontic Clinic at T1 (initial) and T2 (3 months later). At each time point, an intraoral scan was taken by the operator followed by three video scans- two taken by the patient and one by the operator. Three linear and three angular measurements were analyzed using Dental Monitoring’sTM tracking …

Accuracy Of Cephalometric Analyses And Tooth Movements Of Conventional Vs Cbct-Generated Cephalograms, Thanh Khong Ng

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The aim of this study was to compare Ricketts and American Board of Orthodontics (ABO) cephalometric measurements and tooth movements from tracings between conventional lateral cephalograms (Sirona Orthophos XG Plus, Charlotte, NC) and CBCT-generated cephalograms (NewTom 5G; QR srl, Verona, Italy). Materials and Methods: Patients who had bilateral Angle’s class II molar were evaluated. Pre-treatment (T1) and post-treatment (T2) conventional lateral cephalograms (CLCs) and CBCT-generated lateral cephalograms (CBLCs) were traced in Quick Ceph Studio using Ricketts and ABO cephalometric analyses. Linear and angular cephalometric measurements from tracings were compared between the two radiographic modalities using one-sample Wilcoxon signed rank …

A Retrospective Cephalometric Growth Study Of Sagittal Airway In Skeletal Class Ii Patients, Sue V. Kim

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The study retrospectively determined the average sagittal pharyngeal airway widths in Class II males and females between 7 to 16 years of age and changes in sagittal airway with increasing age. Additionally, this study determined whether average airway differs between gender at each age and compared the average airway widths in relation to increasing age between Class I and II patients. Materials and Methods: Longitudinal cephalograms were digitally traced for 38 untreated subjects (23 males, 15 females) from age 7 to 16 with skeletal and dental Class II patterns. These records were previously taken through growth studies conducted between …

Measuring A Sample Of Orthodontic Models/Panographs At Llusd Using The Cr-Eval, Jonathan Michael Drew

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: An index must be used to quantify the improvement in the position of teeth treated by orthodontics. The Cast-Radiograph Evaluation is the index used by the American Board of Orthodontics. The purpose of this study is to use this index to evaluate treatment outcomes in the graduate orthodontic clinic at Loma Linda University from 2012-2016. Materials and Methods: Patients included were comprehensively treated, debonded between 1/1/2012 and 12/31/2016, and under age 30. A total of 80 patients were randomly selected, with 16 coming from each year. The ABO DI was used to score the T1 models, and the CR-Eval …

A Digitized Comparison Using Cone Beam Computed Tomography And Intraoral Scanning, Yvette Carrillo

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The purpose of this study was to evaluate the accuracy of digital workflow by evaluating the absolute technical differences in various scanning methods on jaw models with scanning bodies.

Material and Methods: Twenty identical 3-dimensionally printed mandibular quadrant jaw models with a single implant and scanning body replacing a missing tooth in area #19 were examined. Cone beam computed tomography .STL files were used as the first test group. Intraoral scans were used as the second test group. Desktop scans of each model and the .STL file was used as a control. The .STL files were then …

Comparison Of Antibacterial Activity Of Ozonated Olive Oil And Chlorhexidine Gluconate, Changmin Lee

Loma Linda University Electronic Theses, Dissertations & Projects

Aim: The aim of this in vitro disk diffusion susceptibility test is to compare the antibacterial activity of ozonated olive oil (OzOO) with chlorhexidine gluconate (CHX) against periodontal pathogens, Porphyromonas gingivalis and Aggregatibacter Actinomycetemcomitans. Materials and Methods: The antibacterial activity of two antiseptics, OzOO and CHX, and, two controls, olive oil and normal saline was assessed by disk diffusion susceptibility test. For disk diffusion susceptibility test, two periodontal pathogens, 20 petri dishes for P. gingivalis and 18 petri dishes for A. actinomycetemcomitans, were used. To assess the antibacterial activity, the diameters of the growth inhibition zone were measured with a …