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Browsing by Author "Stewart, Kelton T."
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Item Association Analysis of Class II Division 2 Malocclusion and Two Genes Linked to Hypodontia (MSX1 and PAX9)(2009) Wall, Matthew D.; Kula, Katherine S.; Hartsfield, James K., Jr.; Shanks, James C.; Baldwin, James J. (James Joseph), 1925-; Stewart, Kelton T.Purpose of the Study: Determine if there is an association of the CII/D2 malocclusion and genes linked to hypodontia, namely PAX9 and MSX1. Methods and Materials: One hundred probands with CII/D2 and one hundred non-CII/D2 with no hypodontia were enrolled in this study. Clinical exam, photographs, models, radiographs, and saliva were gathered. DNA was isolated from the saliva and sent for genetic analysis. Single Nucleotide Polymorphisms (SNPs) from the PAX9 and MSX1 genes were analyzed using the LightCycler® 480 to verify the presence of each with the CII/D2 malocclusion. A Hardy-Weinberg test was used to screen for genotyping errors, then a chi-square test was used to evaluate the association of the SNP genotypes. A p-value of 0.05 was considered significant. Results: The Hardy-Weinberg test showed no significant differences between observed and expected counts thus we used them for association analysis. Chi-square analysis indicated no significant association between CII/D2 and the MSX1 rs3821949 and the PAX9 1955734 genotypes. Although a p-value of 0.06 for the PAX9 rs8004560 suggested association, it was considered a grey area and insufficient to conclude that there was significant association. Since the SNP PAX9 rs8004560 was insufficient, additional statistical analysis was also performed on the PAX9 rs8004560 genotype of the CII/D2 affected subjects reported to have hypodontia of any tooth including third molars and excluding third molars. A chi-square test yielded a p-value of 0.08 on the analysis of CII/D2 with hypodontia for any permanent tooth except third molars, which suggested association, but insufficient to conclude a significant association. All other analyses indicated a lack of association of the PAX9 rs8004560 SNP. Conclusions: There is no significant association of CII/D2 and the SNPs MSX1 rs3821949 and PAX9 rs1955734. There is a suggestion that there is an association of the SNP PAX9 rs8004560 and CII/D2. There is a suggestion that there is an association of SNP PAX9 rs8004560 and CII/D2 subjects with hypodontia of any tooth except third molars.Item Correlation between Advanced Dental Admission Test performance and dental MATCH success(Wiley, 2021-04) Deek, Joseph; Albright, David A.; John, Vanchit; Tang, Qing; Stewart, Kelton T.; Orthodontics and Oral Facial Genetics, School of DentistryPurpose/Objectives The Advanced Dental Admissions Test was developed in 2016 to aid residency programs evaluate qualified applicants. Since its conception, however, there have been no studies seeking to evaluate the usefulness of the exam regarding an applicants’ ability to match with a residency program through the Postdoctoral Dental Matching Program (MATCH). The aim of this study was to evaluate the impact of the Advanced Dental Admission Test performance on student MATCH success into a post-doctoral pediatric residency program. Methods This retrospective study evaluated the academic records of pediatric residency applicants using the ADEA PASS and MATCH program between 2017 and 2019. Five scholastic and 7 demographic variables were extracted from student ADEA PASS applications. Applicant MATCH status and preference was obtained from the Postdoctoral Dental Matching Program. Descriptive statistics for each application cycle was calculated and used to evaluate applicant demographic and scholastic data. Correlation coefficients assessed for associations between scholastic/demographic factors and MATCH status/preference. Logistic regression models estimated the probability of MATCH status/preference. Significance was set at 5%. Results An association was found between ADAT scores and MATCH status, but the influence was minimal (odds ratio: 1.004, 95% confidence interval: 1.001-1.008). Applicant age (P < 0.0216) and dental schools that ranked students (P < 0.0002) were the most significant factors for MATCH status and preference, respectively. Conclusions ADAT scores played a minimal role in applicants matching to pediatric residency programs. Applicant age and schools that provide class ranks were found to be significant predictors when considering MATCH status and preference to pediatric residency programs.Item The effect of pH levels on nonlatex vs latex interarch elastics(Allen Press, 2011) Sauget, Paul S.; Stewart, Kelton T.; Katona, Thomas R.; Orthodontics and Oral Facial Genetics, School of DentistryObjective: To evaluate the force decay characteristics of nonlatex vs latex interarch elastics within the normal range of salivary pH levels. Materials and methods: Two nonlatex groups and one latex quasi-control group were tested. Elastics were stretched to 15 mm and were held for 10 seconds (baseline), 4 hours, 8 hours, and 12 hours in artificial saliva solutions with pH levels of 5.0, 6.0, and 7.5. Force magnitudes were measured at 25 mm of activation. Each specimen was used once. Measurements were assessed using three-way analysis of variance (ANOVA). Results: The three-way interaction between group, pH, and time was not significant (P = .13); the group-by-pH interaction also was not significant (P = .70). However, pH-by-time (P = .0179) and group-by-time (P = .0001) interactions were significant. American Orthodontics nonlatex generated significantly higher loads than Auradonics nonlatex. American Orthodontics nonlatex produced significantly higher forces than American Orthodontics latex at 4, 8, and 12 hours, but not at 10 seconds. American Orthodontics latex was significantly stronger than Auradonics nonlatex at 10 seconds, but not at 4, 8, and 12 hours. Conclusions: No clinically significant correlation between pH and force decay was observed.Item The effects of application time of a self-etching primer and debonding methods on bracket bond strength(Allen Press, 2012) Parrish, Brandon C.; Katona, Thomas R.; Isikbay, Serkis C.; Stewart, Kelton T.; Kula, Katherine S.; Orthodontics and Oral Facial Genetics, School of DentistryObjective: To test the manufacturer's recommendation for the application rubbing time of a self-etching primer (Transbond Plus, 3M Unitek) and to compare the resulting bond strength of a resin composite (Transbond XT, 3M Unitek) in the traditional laboratory tension on all four wings with a simulation of the clinical single-wing lift-off debonding instrument (LODI; 3M Unitek). Materials and methods: Flattened stainless-steel maxillary incisor orthodontic brackets (Victory Series, 3M Unitek) were bonded to 108 flattened bovine incisors. The enamel was rubbed with the self-etching primer for 0, 5 (the manufacturer's recommendation), and 10 seconds during a 10-second application. Traditional four-wing and LODI simulated debonding forces and the adhesive remnant index (ARI) were recorded. Results: One-way analysis of variance testing among rubbing times and debonding methods indicated a significant difference in strength with 0 and 5 seconds of rubbing and between traditional and LODI simulated tension. The bond strengths were higher in the ARI = 1 subset compared to the ARI = 3-5 subsets. Conclusions: The manufacturer's recommendation for primer rubbing time produced the highest bond strength. Less force is required for debonding when tension is applied to one wing (LODI simulation) vs on all four wings.Item EFFECTS OF ORTHODONTIC MINI-IMPLANT DIAMETER ON MICRODAMAGE.(Office of the Vice Chancellor for Research, 2012-04-13) Cruz, Enrique; Liu, Sean; Sun, Jun; Blanchard, Steven B.; Soto, Armando; Stewart, Kelton T.; Allen, Matthew R.; Liu, SeanMicrodamage reduces bone mechanical properties and thus could possi-bly contribute to implant failure. The objective of this study was to investi-gate whether the diameter of mini-implants (MI) affects microdamage gen-eration and whether this differs between the mandible and maxilla due to their contrasting cortical thicknesses. Methods: Maxillary and mandibular quadrants of 5 dogs were randomly assigned to receive, in situ, no interven-tion (control), pilot drilling only, or pilot drilling plus one of three diameters of MI: 1.4 (n=18), 1.6 (n=18), and 2.0 mm (n=18). Microdamage was as-sessed on basic fuchsin stained sections using epifluorescence microscopy. Results: No microdamage was found in the non-drilling controls. Pilot drill-ing produced only minimal microdamage in the maxilla but more microdamage in the mandible. There was significantly higher microdamage generated in the mandible, compared to the maxilla (p<0.05). In the maxil-la, although insertion of all implants produced higher microdamage than the control and pilot drilling, there were no differences between the 3 MI diame-ters. In the mandible, insertion of implants generated significantly higher microdamage than the control, but it did not produce higher microdamage than pilot drilling. Similarly, no differences in microdamage were found be-tween 3 MI diameters. Conclusion: Insertion of MIs in the mandible pro-duced higher microdamage than in the maxilla, which may explain that the higher MI failure rate in the mandible. Implant diameter did not affect over-all microdamage burden in either jaw. Microdamage was mostly generated by pilot drilling through the cortex in the mandible, while microdamage in the maxilla was mainly produced when manual inserting MIs after pilot drill-ing.Item The impact of dental curriculum format on student performance on the national board dental examination(Wiley, 2022-06) Yang, Sireen; Edwards, Paul C.; Zahl, David; John, Vanchit; Bhamidipalli, Surya S.; Eckert, George J.; Stewart, Kelton T.; Orthodontics and Oral Facial Genetics, School of DentistryPURPOSE/OBJECTIVE: The effectiveness of different curriculum types has long been debated by dental educators aiming to provide the best education possible to their students. This study aimed to evaluate the effect of curriculum type (hybrid problem-based learning [PBL] vs. traditional) on National Board Dental Examination (NBDE) part I and II pass rates METHODS: A retrospective cohort study was conducted with a hybrid PBL cohort and traditional cohort. NBDE part I and II pass rates for the two cohorts were acquired, along with demographic and scholastic variables. Pass rates, scholastic variables, and demographic variables were compared using two-sample t-tests and chi-square tests. Associations of the variables with pass rates were analyzed using logistic regression. Significance was set at 5% RESULTS: No significant differences in pass rates for NBDE part I and II were observed between the cohorts. Cumulative dental school grade point average (GPA) was found to be an independent predictor of success for NBDE part I (odds ratio (OR): 1.40, 1.24-1.59 for 0.1 point intervals) and II (OR: 1.34, 1.18-1.52 for 0.1 point intervals), (p < 0.01). DAT biology sub-score was found to be predictive of success for NBDE part I (OR: 1.58, 1.14-2.19), (p = 0.01) CONCLUSIONS: No significant difference in NBDE part I and II pass rates between the cohorts was found. Dental school GPA was the most predictive variable for success on NBDE part I and II. These findings may be helpful considerations as institutions assess the structure of their school curricula.Item The impact of the COVID-19 pandemic on U.S. orthodontic practices in 2020(Elsevier, 2021-10-04) Motevasel, Hengameh; Helms, Lana R.; Eckert, George J.; Stewart, Kelton T.; Albright, David A.; Orthodontics and Oral Facial Genetics, School of DentistryINTRODUCTION: This study aimed to investigate the immediate impact and long-term implications of severe acute respiratory syndrome coronavirus on orthodontic practices in the United States in 2020. METHODS: A 35-item survey was developed and validated to investigate the impact of the coronavirus disease (COVID-19) pandemic on the orthodontic specialty. The survey contained 5 domains, including respondent's demographic information, COVID-19 information acquisition, practice ramifications of the COVID-19 pandemic, financial implications of the COVID-19 pandemic, and patient management strategies during the COVID-19 pandemic. This voluntary survey acquired responses from active orthodontists in the United States. Associations of demographic and practice characteristics with items related to COVID-19 were assessed using chi-square tests, with a 5% significance level. RESULTS: The survey was disseminated to 5,694 orthodontists, and 507 complete surveys were obtained (response rate of 8.9%). Respondents indicated that they obtained the most useful information regarding the COVID-19 pandemic through professional associations and internet or online news resources. However, 30% of the orthodontists believed information regarding personal financial guidelines was lacking. Most respondents identified delayed treatment progress and temporary staff layoffs as the 2 most negative ramifications of mandated office closures. Approximately 93% of practices applied for and used some sort of stimulus funding offered through the Coronavirus Aid, Relief, and Economic Security Act. Respondents indicated that the COVID-19 related office closures resulted in an average of 50% decrease in net revenue. CONCLUSIONS: The survey found that the COVID-19 pandemic had a broad and significant impact on patient care and financial aspects of U.S. orthodontic practices in 2020. Although generally accepting of the federal and state recommendations, respondents appeared to desire more guidance during the early phase of the pandemic.Item Is There a Correlation Between Airway Volume and Maximum Constriction Area Location in Different Dentofacial Deformities?(Elsevier, 2020) dos Santos, Liseane F.; Albright, David A.; Dutra, Vinicius; Bhamidipall, Surya S.; Stewart, Kelton T.; Polido, Waldemar D.; Orthodontics and Oral Facial Genetics, School of DentistryPurpose The purpose of the present study was to correlate the airway volume and maximum constriction area (MCA) with the type of dentofacial deformity in patients who required orthognathic surgery. Materials and Methods The present retrospective cohort study included orthognathic surgery patients selected from the private practice of one of us. The selected cases were stratified into 5 different groups according to the clinical and cephalometric diagnosis of their dentofacial deformity. The preoperative airway volume and anatomic location of the MCA were calculated using the airway tool of the Dolphin Imaging software module (Dolphin Imaging and Management Solutions, Chatsworth, CA) and correlated with the diagnosed dentofacial deformity. Differences in the pretreatment airway volumes and MCA location were compared among the deformities. Results The MCA location was more often the nasopharynx for maxillary deficiency and the oropharynx for mandibular deficiency deformities. The nasopharynx volume was significantly smaller statistically ( P < .005) for maxillary deficiency plus mandibular excess compared with mandibular deficiency. The hypopharynx volume was significantly smaller statistically ( P < .005) for vertical maxillary excess plus mandibular deficiency than for both maxillary deficiency and maxillary deficiency plus mandibular excess. No statistically significant difference was found among the different deformity groups in relation to the mean airway volume ( P > .005). Conclusions The location of the airway MCA seems to have a strong correlation with the horizontal position of the maxilla and mandible. The MCA in maxillary deficiencies (isolated or combined) was in the nasopharynx, and the MCA in mandibular deficiencies (isolated or combined) was in the oropharynx. Clinicians should consider these anatomic findings when planning the location and magnitude of orthognathic surgery movements to optimize the outcomes.Item Microdamage generation by tapered and cylindrical mini-screw implants after pilot drilling(2014-09) Taing-Watson, Emily; Katona, Thomas R.; Stewart, Kelton T.; Ghoneima, Ahmed; Chu, Gabriel T. M.; Kyung, Hee-Moon; Liu, Sean S.; Department of Orthodontics and Oral Facial Genetics, IU School of DentistryObjective: To investigate the relationship between mini-screw implant (MSI) diameter (1.6 vs 2.0 mm) and shape (tapered vs cylindrical) and the amount of microdamage generated during insertion. Materials and Methods: Thirty-six cylindrical and 36 tapered MSIs, 6 mm long, were used in this study. Half of each shape was 1.6 mm in diameter, while the other half was 2.0 mm. After pilot drilling, four and five MSIs were inserted, respectively, into fresh cadaveric maxillae and mandibles of dogs. Bone blocks containing the MSIs were sectioned and ground parallel to the MSI axis. Epifluorescent microscopy was used to measure overall cortical thickness, crack length, and crack number adjacent to the MSI. Crack density and total microdamage burden per surface length were calculated. Three-way analysis of variance (ANOVA) was used to test the effects of jaw, and MSI shape and diameter. Pairwise comparisons were made to control the overall significance level at 5%. Results: The larger (2.0 vs 1.6 mm) cylindrical MSIs increased the numbers, lengths, and densities of microcracks, and the total microdamage burden. The same diameter cylindrical and tapered MSIs generated a similar number of cracks and crack lengths. More total microdamage burden was created by the 2.0-mm cylindrical than the 2.0-mm tapered MSIs. Although higher crack densities were produced by the insertion of 1.6-mm tapered MSIs, there was no difference in total microdamage burden induced by 1.6-mm tapered and 1.6-mm cylindrical MSIs. Conclusions: Pilot drilling is effective in reducing microdamage during insertion of tapered MSIs. To prevent excessive microdamage, large diameter and cylindrical MSIs should be avoided.Item Orthodontic and oral health literacy in adults(Public Library of Science, 2022-08-18) McCarlie, V. Wallace, Jr.; Phillips, Morgan E.; Price, Barry D.; Taylor, Peyton B.; Eckert, George J.; Stewart, Kelton T.; Orthodontics and Oral Facial Genetics, School of DentistryObjective: The primary aim of the study was to determine levels of literacy in both oral health and orthodontics in an adult population. The secondary study aim was to investigate differences in literacy between males and females. Methods: Participants included individuals 18 years or older seeking dental treatment at the East Carolina University (ECU) School of Dental Medicine. To determine levels of oral health literacy (OHL) and orthodontic literacy (OrthoL), validated instruments were administered, including the Rapid Estimate of Adult Literacy in Medicine and Dentistry, the Oral Health Literacy Instrument and its separate scales, and a questionnaire on orthodontic literacy. Summary statistics were computed, and statistical significance was set at 0.05. Results: One hundred seventy-two individuals participated in the study and had a mean age of 55.03 (range:18-88). Greater than 70% of the sampled population exhibited inadequate or marginal oral health knowledge. Additionally, greater than 70% of the sample possessed no more than an 8th grade reading level, with regard to basic medical and dental terms. Higher education was weakly associated with higher OrthoL and OHL. Higher age was also weakly associated with lower OrthoL and OHL. Males on average exhibited significantly higher OHL (p < .05) but there were no OrthoL differences between males and females. Dental visit frequency was not associated with OrthoL or OHL. Conclusion: Low levels of OrthoL and OHL were observed in the study. While males demonstrated a higher level of OHL than females, neither age nor the occurrence of dental appointments significantly influenced levels of literacy.
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