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Twitter analysis of the orthodontic patient experience with braces versus InvisalignNoll, Daniel A 01 January 2016 (has links)
The purpose of this study was to examine the orthodontic patient experience with braces compared to Invisalign® by means of a large-scale Twitter sentiment analysis. A custom data collection program was created to collect tweets containing the words “braces” or “Invisalign.” A hierarchal Naïve Bayes sentiment classifier was developed to sort the tweets into one of five categories: positive, negative, neutral, advertisement, or not applicable. Among the 419,363 tweets applicable to orthodontics collected, users posted significantly more positive tweets (61%) than negative tweets (39%) (p-value = ® tweets (p-value=0.4189). In conclusion, Twitter users express more positive than negative sentiment about orthodontic treatment with no significant difference in sentiment between braces and Invisalign® tweets.
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Long lower anterior face height: phenotypic diversityFinlen, Kate Elizabeth 01 May 2017 (has links)
Introduction: The hyperdivergent facial form is typically characterized by a long lower anterior facial height (LAFH), steep mandibular plane angle, and skeletal open bite. The purpose of our study was to further explore morphologic variation within long LAFH subjects using geometric morphometric methods. Methods: Cephalograms of 147 individuals (n= 147; 87 female, 60 male; age range: 16-68 years) with LAFH to total anterior facial height (TAFH), ratio (LAFH/TAFH), at or above 57.4% were studied. Cluster analysis and canonical variate analysis captured phenotypic variation and identified homogenous groups. Results: Cluster analysis resulted in three discrete long LAFH phenotypes that varied along vertical and anteroposterior dimensions. Conclusions: We found significant morphologic variation within the sample population of long LAFH individuals. Three phenotypes with varied vertical and anteroposterior discrepancies were revealed through the cluster analysis. Within our sample, we found both convergent and divergent facial patterns with concomitant cranial base rotation and posterior ramal border displacement. Vertical variation was largely independent of anteroposterior discrepancies.
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Remineralization effectiveness of MI Paste Plus - a clinical pilot studyClark, Sarah Elizabeth 01 May 2011 (has links)
Purpose: The purpose of this study is to evaluate the effectiveness of MI Paste Plus™ in increasing remineralization and improving the esthetic appearance of white spot lesions in patients who have been treated with fixed orthodontic appliances. Material and Methods: A total of twelve subject participants aged twelve to twenty years were selected in this pilot study. The six treatment group subjects were treated with MI Paste PlusTM every three weeks in-office (4 applications) and via invisible retainer every night for a total of 12 weeks. The in-office application consisted of a 1 minute 35% phosphoric acid and a 5 minute MI Paste PlusTM contact time. At home, the subjects went about their routine oral hygiene practices, but added MI Paste PlusTM to their invisible retainer before bedtime which was worn throughout the night. Photographs and quantitative light-induced fluorescence (QLF) were used to calculate white spot lesion area and ∆F values respectively. Results: A significant difference was found in the control group for the area of the white spot lesion in antimere teeth #6 and #11. When analyzing the white spot lesion area in the treatment group, significant differences were found in tooth #6, antimere teeth #6 and #11, antimere teeth #8 and #9, as well as all teeth. ∆F values for all teeth in both the control and treatment groups were significant. Conclusion: In-office and at home treatment with MI Paste Plus™ showed a statistically significant reduction in photographic lesion area when compared to controls. Both MI Paste Plus™ and a fluoride toothpaste will provide some remineralization of white spot lesions.
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Passive eruption patterns in first molarsHoelscher, Benjamin Charles 01 May 2011 (has links)
OBJECTIVE: The purpose of this study is to determine the eruption patterns of maxillary and mandibular first molars from the first occlusal contacts to adulthood. Previous studies have failed to obtain measurements into adulthood or have not been longitudinal in design. By using a measurement during the subjects' adulthood, a better estimate of the changes that occur between the tooth and the gingival margin throughout growth and aging can be obtained. METHODS: The material for this research project was obtained from the Meredith Facial Growth Study from the University of Iowa Orthodontics Department. Records from a set of 64 subjects (35 males and 29 females) were used. Each of these patients had intraoral models taken throughout adolescence into adulthood. A final model was available for each subject in their twenties. Twenty-eight subjects had final records available in their forties (14 males and 14 females). Measurements were recorded for the maxillary first molars (Teeth 3 and 14), and the mandibular first molars (Teeth 19 and 30). Measurements were taken at eleven time points for all sixty-four subjects starting at year 8 and yearly until age 18 with a final measurement taken on a model from the patient's twenties. A subset of twenty-eight subjects contained measurements in their forties. Bitewing Radiographs were also used to measure changes in alveolar bone height at 12, 20, and 40. RESULTS AND CONCUSIONS: Alveolar bone heights and their changes over time measured from the CEJ indicate that the sample population had a stable periodontium. Crown heights at age 20 and 40 were significantly greater than age 11. At age 40, crown heights were significantly greater than age 20. Teeth continue to erupt into a patient's forties in the absence of bone loss and attrition.
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Phenotype-genotype correlation between the Hippo pathway and 3D craniofacial phenotypesArbon, Jed 01 May 2016 (has links)
Introduction: The purpose of this study was to examine phenotypic expression of craniofacial form, shape, and size as it relates to the genotype of an individual. Shape analyses were completed on 3-D images of each subject's craniofacial structure by landmarking 45 points of interest on the cranial base, facial bones, and upper and lower jaws. A candidate gene analysis was undertaken focusing on specific genes in the Hippo Signaling Pathway to examine genotype-phenotype correlations that play a role in craniofacial development. This study is a continuation of a larger project aimed at the identification of candidate genes associated with human dento-skeletal bite problems led by Dr. Lina Moreno-Uribe.
Methods: The sample size for our study included 166 individuals who had never been treated orthodontically at the time of records. Each individual was genotyped and a CBCT of the craniofacial complex was captured. Each CBCT image was landmarked by a single observer using 45 points to mark points on the cranial base and facial bones including the maxilla and mandible. General Procrustes superimposition was used to find correlations with phenotype and genotype. Size analysis was completed with average Euclidean Distances and ANOVA analysis.
Results: 2 SNP's from the FOX03 gene had significant associations with size. The AA genotyped individuals appeared larger in overall size than AB genotyped individuals. 3 SNP's had statistically significant associations with facial form. The FOX06 SNPs had significant associations with increased anterior-posterior growth of the maxilla. The AJUBA SNP had significant associations with increased overall craniofacial breadth.
Conclusion: Genes in the Hippo signaling pathway have specific roles in the development of facial form and size.
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Effect of temporary prosthetic mandibular advancement on velopharyngeal closure for speechShin, Kyungsup 01 July 2015 (has links)
Introduction: Velopharyngeal inadequacy (VPI) may result in inappropriate oral/nasal coupling during the production of speech sounds, resulting in unwanted nasal resonance and/or nasal air emission. Orthognathic surgeries such as maxillary and/or mandibular advancements are also known to change skeletal and muscular structures resulting in changes affecting velopharyngeal closure (VPC). Although many studies have reported on the effect of maxillary advancement surgery on VPI for patients with cleft lip and palate, the effect of mandibular advancement on VPI has not been studied at length. The purpose of this study was to elucidate the effect of temporary prosthetic mandibular advancement on velopharyngeal function.
Methods: Fourteen subjects (7 males, 7 females) with no history of craniofacial abnormalities or speech disorders were recruited. The mean age was 35 years (range = 26-60). Acoustic nasalance measurements were obtained during nasal sentences and during sentences without nasal consonants in two conditions; normally, and while wearing an elastic mandibular advancement (EMA) appliance to advance the mandible by 13mm. In addition, subjects were asked to produce five repetitions of the sentence "Ten men came in when Jane left" while recordings were obtained with a videoendoscopy/phototransducer system that sensed the amount of light passing through the velopharyngeal orifice. The endoscope and fiber optic light were inserted through the subject's middle nasal meatus and positioned above the velum. The phototransducer fiber was extended through the velopharyngeal port into the upper oropharynx to detect light passing through the orifice as the velopharyngeal mechanism opened and closed. Individual subject's outcomes with and without the EMA appliance were analyzed statistically using paired t-test for Nasalance test, and one-way ANOVA/independent samples t-test for phototransducer test.
Results: Nasalance did not deteriorate, but significantly decreased for the ‘nasal’ sentences after mandibular advancement, whereas changes in nasalance were not significant for the sentences containing no nasal consonants after mandibular advancement. Mandibular advancement by a 13 mm using an EMA appliance did not significantly affect VPC. Instead, large variability among subjects in response to mandibular advancement. For 7 of the 14 subjects, the extent of VPC decreased significantly (p < .05) under the advanced mandible condition compared to the normal condition (without the EMA appliance). On the other hand, 5 subjects showed significantly (p < .05) increased VPC when their mandibles were advanced. For 2 subjects, VPC was not significantly changed with the advanced mandible.
Conclusions: The outcomes of this study suggested that there was no statistical evidence to support that nasality was deteriorated by a 13mm mandibular advancement, which agreed with recent studies describing velopharyngeal function and nasality after orthognathic surgeries. VPC was not affected by mandibular advancement. Responses of the nasalance and VPC to mandibular advancement were dependent on the individuals. Further investigation such as electromyography method is needed to understand how velopharyngeal function and speech respond to mandibular advancement more definitely.
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Nasal septal deviation in a longitudinal growth sampleSwenson, Karl Edward 01 May 2012 (has links)
Objective: This retrospective longitudinal study attempts to determine the ontogenetic patterning of nasal septal deviation and if there is a relationship between a deviated septum and facial form growth and development. Methods: Nineteen females and twenty males were selected from the Iowa Facial Growth Study. Eighteen lateral cepalometric variables were analyzed and septal deviation was quantified using a percentage of deviation. A generalized Procrustes analysis was used to scale landmarks and generate principal components. Pearson correlation coefficients were used to analyze differences in shape. A Mann Whitney U-Test was used to analyze changes in septal deviation. Results: The first three principal components explained 56.23% of the variance. Only PC1 was significantly correlated with centroid size (r=0.82, P<0.0001). Mean percentage of septal deviation (0.620% ± 0.463%) was present at the youngest age group (3-4.9 years) and increased in each age group until adulthood, defined as over the age of 20 (0.991% ± 0.519). None of the first three principal components were found to be correlated to percentage of septal deviation. Conclusions: Nasal septal deviation has been found to increase in a longitudinal sample of subjects of northern European descent. Nasal septal deviation represents a disjunction in the growth of the nasal septum with the rest of the face. The amount and timing of nasal septal deviation that can cause nasal obstructions leading to vertical growth changes was not analyzed in this study and will require future study.
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Passive eruption patterns in central incisorsGuymon, Russell John 01 May 2010 (has links)
OBJECTIVE: The purpose of this study is to determine the eruption patterns of maxillary and mandibular central incisors from the first occlusal contacts to adulthood while comparing the differences in male and female eruption patterns. Previous studies have failed to obtain measurements into adulthood. We hope by using a final measurement during a subjects' adulthood we can better estimate final eruption times and measurements.
METHODS: The material for this research project was obtained from the Meredith Facial Growth Study from the University of Iowa Orthodontics Department. Records from a set of 64 subjects (35 males and 29 females) were used. Each of these patients had intraoral models taken throughout adolescence into adulthood. A final model was available for each subject in their twenties. Twenty-eight subjects had final records available in their forties (15 males and 13 females). Measurements were recorded for the maxillary central incisors (Teeth 8 and 9), and the mandibular central incisors (Teeth 24 and 25). Measurements points were the incisal edge of the tooth to the most apical (deepest) curvature of the gingival margin. Measurements were taken at eleven time points for all sixty-four subjects starting at year 8 and yearly until age 18 with a final measurement taken on a model from the patient's twenties. A subset of twenty-eight subjects contained measurements in their forties.
RESULTS AND CONCUSIONS: Differences between male and female mean crown heights were only present on maxillary incisors at early ages. Tooth 8 at ages 8 to 12 and for tooth 9 at ages 10 to 11. All other ages and all other teeth showed no gender differences. Eruption rates differ for males and female for tooth 8 only. Teeth 9, 24, 25 all showed no differences in their rate of increasing crown height over time. A significant age effect for teeth 8 and 9 and also teeth 24 and 25 in the subset studies was found. There was no significant factor between age and gender. Teeth heights at age 20 and 40 were significantly greater than age 11. At age 40 heights were significantly greater than age 20. Teeth continue to erupt unto a patient's forties.
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Effect of mandibular advancement on symphyseal formHughes, Justin Marshall 01 May 2016 (has links)
Much research has been done to understand the complex process of facial growth and development for decades. Recently, the form and function of the human mandibular symphysis has been of interest. The human symphysis theoretically experiences three types of strains during function, which may influence symphyseal shape and development. These forces are influenced by the size and position of the mandible relative to the muscles that act upon it. The purpose of this study is to determine whether an increase in mandibular length through surgery leads to increased skeletal indicators of resistance to wishboning forces. We retrospectively collected a sample of 47 subjects who had undergone mandibular advancement surgery and compared their pre- and post-surgical radiographs to examine for any changes. The results of our analysis did not provide any evidence to suggest increased wishboning resistance as a result of surgical lengthening. Perhaps there were truly not changes in the symphysis, or that we were unable to detect them due to limitations of using two-dimensional images on an adult population with a relatively short follow-up. Further research is needed to understand the role of function in the form of the human mandibular symphysis.
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Differential growth of the frontonasal suture in rabbitsVroman, Maura Josephine 01 January 2010 (has links)
The purpose of this study was to substantiate previous claims that differential growth across the frontonasal suture occurs and if this differential growth pattern is caused by an increased mitotic rate of the nasal bone.
Two six week old New Zealand White Rabbits were given calcein 20mg/kg IA, demeclocycline 20mg/kg IA, and BrdU 40mg/kg IA on Days 1, 11, and 14, respectively. The animals were euthanized using Ketamine 31.6mg/kg IM and Pentobarbital 100mg/kg IV. The frontonasal suture was removed from the rabbit and divided into hemisections. The right hemisection was histologically processed using standard calcified methods which were modified and used for smaller bone sections at the Comparative Orthopaedic Research Laboratory, School of Veterinary Medicine, University of Wisconsin. The left hemisection was reserved for BrdU staining at the Central Microscopy Research Facility, University of Iowa. The resultant slides were imaged and photographed using an Olympus BX-40 microscope and measured using ImageJ software (NIH). Means and standard deviations were calculated for interlabel distance and mineral apposition rate (MAR).
All frontonasal suture sites demonstrated double fluorochrome labeling. Samples F2-2 and M2-1 demonstrated the predicted differential growth pattern. Samples F2-1 and M2-2 did not. No suture sites demonstrated positive staining for BrdU. Although the sample size was small (n=2), this may demononstrate a trend toward differential growth of the suture.
Due to the small sample size, the labeling protocol used in this study provided limited quantitative data. Although two sections did not demonstrate more bone deposition or faster mineral apposition rate of the nasal bone, it is important to consider that these sections were of poorer quality when compared to the other sections. Higher quality sections with clear, measurable margins showed a difference between frontal and nasal bone growth in both morphology and mineral apposition rate.
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