In this paper, a new method combining imprint lithography and multiimprint was discussed to improve the generic TFT process. In order to apply the multilayer imprint, the alignment machine is essential for the whole process. Although there are many types of equipment available on the market, the cost of those alignment apparatuses is too expensive. In this paper, a simple theorem is employed to complete a low cost alignment machine with alignment accuracy to 5 £gm. Besides, in order to develop new TFT imprint photoresist, three kind of materials, AZ-series photoresist (AZ-650 a positive photoresist), HOSP (Hygrido Organic Siloxane Polymer) and SE-812, are tested for imprint and evaluate the applications of these materials in the future. The AZ-650 suits imprint process in this experiment.

The newly emerging Clarity™ Clear Aligner System from 3M has set out to address one of the biggest pitfalls of thermoplastic aligners: accuracy of orthodontic movements. The 3M Clarity™ Clear Aligner System is unique among clear aligners because it employs a proprietary, sophisticated machine-learning algorithm to design orthodontic movement schematics. The core of the Clarity™ Aligner System is artificial intelligence, meaning that a prospective analysis of preliminary data is essential for the development and improvement of the accuracy of the algorithm. This study investigates movement and accuracy of the Clarity™ Aligner System, from a preliminary data subset from ongoing prospective, randomized clinical trials. Movement from the first trial subset is examined in terms of the following movement factors: secondary premolar-secondary premolar (5+5 in the Palmer system) arch expansion or crowding resolved, absolute rotation, absolute mesial-distal tipping, and absolute torque for both the crown and root. These movements are further examined according to specific tooth types. Both actual observational orthodontic movements and theoretical movements are designed by the Clarity™ System. The accuracy of actual movement in terms of theoretical movements is calculated; however, it is impossible to calculate the significance of these accuracies due to a complete lack of benchmark movement values for the clear aligner market. There are no benchmark values to compare to, so orthodontic movements will be critically examined for performance, and casually compared to alternative aligner systems. Identifying potential weaknesses in the Clarity™ Aligner System is imperative for maximizing its effectiveness.

Introduction: Surgically Facilitated Orthodontic Therapy (SFOT) has been utilized for years to overcome the limitations encountered with traditional orthodontic treatment of dentoalveolar and alveoloskeletal malocclusions. The procedure, which consists of full flap corticotomies and bone grafting, has many proposed benefits including increased speed and range of tooth movement. The purpose of this study is to evaluate arch expansion in patients treated with SFOT and clear aligners. Materials and Methods: A retrospective cohort study design was used to evaluate 51 consecutive adult patients that were treatment planned for significant arch expansion with corticotomies, bone grafting, and clear aligners. 17 of the 51 patients refused the surgical procedure and served as controls. Eight transverse arch width measurements were obtained at three different time points (Initial, ClinCheck, Refinement). Five calculations were performed to determine the magnitude, predictability, and efficiency of arch expansion. Results: The difference in treatment time between the two groups was statistically significant at 5.2 months (P < .0001). On average, corticotomies reduced the length of treatment by 46% and increased the rate of expansion 2.4x. Patients that received SFOT achieved a greater magnitude (+28%) of expansion at a significantly higher rate (P< 0.002) than controls for all eight interarch measurements. The SFOT group displayed higher predictability (% goal achieved) and a smaller difference between predicted and achieved tooth movements for all measures obtained. The mean age for the entire sample was 42.81 (+12.51 years). Conclusion: Arch expansion with corticotomy-assisted clear aligner therapy is significantly more effective, efficient, and predictable than with clear aligners alone. The predictability of expansion with aligners appears to have a higher range than initially thought, even in patients that do not receive corticotomies.

There are about 20,000 genes in the human genome. The lowly nematode worm, C. elegans, has about the same number of genes. How could two organisms that are so different arise from a similar number of genes? The answer is epigenetics, or the factors that help control when and where genes are expressed. There are many layers that comprise the epigenetic control of genes. One of which is the structure or architecture of chromatin. Chromatin is a complex of DNA and proteins. Histone proteins with DNA wrapped around them form the fundamental component of chromatin, the nucleosome. Chromatin exists in two forms, euchromatin and heterochromatin. Euchromatin is made of loosely packed nucleosomes while in heterochromatin nucleosomes are tightly packed. Genome elements are not accessible in heterochromatin but are in euchromatin. In this way chromatin architecture provides a layer of control of genetic expression. Where nucleosome form is a function of several factors including the underlying DNA sequence, and binding competition between histones and other DNA binding proteins. Here we test the ability of various DNA sequences to position and repel histone proteins in C. elegans worms. We find that the 601sequence can position nucleosomes and that the PRS-322 sequence does repel nucleosomes in vivo. Assessing chromatin architecture requires sequences to be aligned to a reference genome, however, there are numerous programs with which to do this. Each program performs this task in a different way. These differences can have a large impact on the downstream analysis of the results. To this end, we have tested various alignment programs to assess how well they align reads to a reference genome. Here we have found that Bowtie2, BWA, and Chromap perform alignments accurately and we suggest using them. As an organism develops its genetic expression changes. This change in expression is often the result of temporally specific genomic elements such as enhancers. Understanding when enhancers are accessible during development can lead to a better understanding of the genetic control needed for development. Here we utilize data gathered at specific developmental stages in C. elegans to elucidate enhancer accessibility. In this work we have furthered the understanding of epigenetic control of expression by quantifying positioning and repelling sequences, testing read mapping programs for accuracy and identifying temporally specific enhancers in developing worms.

No description available.

The relationship between applied force and aligner thickness is poorly understood. Therefore, the aims of the present study were to: 1) Evaluate the effect of initial material thickness on force output of clear aligners; and 2) Recommend a consistent, repeatable method for measuring aligner cross-section and distribution. A total of 40 clear aligners were fabricated over stereolithographic (SLA) models with ideal dentition, using proprietary gRxh material in four different thicknesses: (10) Rx15 [0.015h], (10) Rx20 [0.020h], (10) Rx30 [0.030h], (10) Rx40 [0.040h]. For measuring initial force output when tipping a tooth, a custom-made force measurement apparatus (FMA) was used with the upper right central incisor translated facially 0.25 mm. All six components of force and torque were measured (Fx, Fy, Fz, Tx, Ty, Tz) over a 16 second period of time upon seating each aligner. After gathering FMA data, cross-section and distribution of aligner material thickness was then measured using three methods for comparison: hall effect transduction, computed tomography (CT) scanning, and cross-sectional analysis under a stereomicroscope. All measurements were taken along the mid-sagittal plane of the facial surface of the upper right central incisor. Force output and variability both generally increased with an increase in material thickness. The range of measured forces were 3.5 to 28 times higher than ideal tipping forces reported by Proffit. The results for lingual force correlated well with those of total force (ã(Fx)2 + (Fy)2 + (Fz)2). As for the thickness measurement results, the hall effect transducer (HET) data correlated well with that of the CT scan. The stereomicroscope produced values that were relatively elevated. Mean measurements taken with both HET and CT consistently got smaller when moving from occlusal to middle to gingival points. The same trend was noted with the stereomicroscope, but with less consistency. The thinner Rx15 material appeared best suited for lingual tipping of a maxillary central incisor in vitro. The hall effect transducer produced simple measurements that were extremely similar to those from the CT scan, and appears to be a suitable stand-in for the more expensive and labor intensive CT scanning process. / Oral Biology

The purpose of this study was to investigate differences in case confidence, treatment management, and Invisalign® expertise between orthodontists and general dentists. A survey was mailed to 1,000 randomly selected orthodontists and general dentists, respectively, who are Invisalign® providers, and results were analyzed. The results indicated that orthodontists treated significantly more Invisalign® cases and received more Invisalign® training than general dentists (P

Introduction: Orthodontic and orthopedic expansion is necessary to create space to resolve crowding due to arch deficiency or tooth size discrepancy. The Invisalign First clear aligner appliance as a modality for early interceptive orthodontic treatment has become incorporated into orthodontic practices in very recent years. The present study aims to investigate the magnitude of expansion of the Invisalign First clear aligner appliance compared to a Schwartz removable expander in patients with mixed dentition. Additionally, the study aims to compare the efficacy and predictability of Invisalign First clear aligners in this population. Materials & Methods: In this retrospective study, a sample was collected from a single orthodontist practitioner. The sample consisted of 34 patients, 16 patients treated with Invisalign First clear aligners only (Group1) and 19 patients treated with a Schwartz removable appliance and Invisalign First clear aligners (Group 2). Intraoral scans of four timepoints, initial (T1), post-expansion for Group 2 only (T1Exp), first refinement (T2), and final (T3), and planned Clincheck goal (P) model from Clincheck software were imported to Align Technology’s digital measure program (Quantify©). Arch widths and molar inclinations were measured at each timepoint and the changes between timepoints were calculated. Predictability of arch expansion was calculated as T13 (change between initial and final) divided by the Planned dimension multiplied by one hundred. A two sample t-test was used to assess differences in the changes in arch widths and predictability of expansion between two groups. Results: There were statistically significant differences found in the magnitude of expansion and predictability of arch expansion between two groups. Group 2 showed a greater amount of expansion and predictability. Group 1 showed about 50-60% of the planned expansion at the end of treatment. In regards to magnitude of expansion when comparing the two groups, the efficacy predictability of transverse dimensional changes were significantly greater in the Group 2 compared to Group 1, 83% vs 56% (p = 0.001), respectively. The changes in inclination were similar in both groups, with no statistically significant differences.Conclusions: There is a significantly greater amount of expansion and greater predictability with the Schwartz removable appliance compared to the Invisalign First clear aligner appliance in the mixed dentition. The predictability of Invisalign First was 56% and indicates a significant overcorrection of arch expansion is required at the virtual treatment planning stage in Clincheck in order to obtain the arch expansion that was planned

In this dissertation, new approaches in the design of a voice transformation (VT) system for Turkish are proposed. Objectives in this thesis are two-fold. The first objective is to develop standard speech corpora and segmentation tools for Turkish speech research. The second objective is to consider new approaches for VT. A triphone-balanced set of 2462 Turkish sentences is prepared for analysis. An audio corpus of 100 speakers, each uttering 40 sentences out of the 2462-sentence set, is used to train a speech recognition system designed for English. This system is ported to Turkish to obtain a phonetic aligner and a phoneme recognizer. The triphone-balanced sentence set and the phonetic aligner are used to develop a speech corpus for VT. A new voice transformation approach based on Mixed Excitation Linear Prediction (MELP) speech coding framework is proposed. Multi-stage vector quantization of MELP is used to obtain speaker-specific line-spectral frequency (LSF) codebooks for source and target speakers. Histograms mapping the LSF spaces of source and target speakers are used for transformation in the baseline system. The baseline system is improved by a dynamic programming approach to estimate the target LSFs. As a second approach to the VT problem, quantizing the LSFs using k-means clustering algorithm is applied with dimension reduction of LSFs using principle component analysis. This approach provides speaker-specific codebooks out of the speech corpus instead of using MELP&#039 / s pre-trained LSF codebook. Evaluations show that both dimension reduction and dynamic programming improve the transformation performance.

INTRODUCTION: Les gouttières thermoplastiques orthodontiques doivent souvent être retirées par les patients avant de consommer des aliments ou des liquides autres que l’eau. Cette précaution évite notamment des changements de couleur au niveau du matériau les constituant. Des études antérieures ont concentré leurs recherches sur des changements de coloration chez des marques limitées d’aligneurs thermoplastiques en excluant certaines marques américaines populaires. OBJECTIFS: L’objectif principal de cette étude vise à évaluer la résistance au changement de teinte du polymère formant trois différentes marques d’aligneurs américaines. Un but secondaire est de comparer le pouvoir de retrait de taches de deux produits nettoyants conçus pour ces appareils amovibles. Un but tertiaire est d’évaluer le type de polymère qui constitue les surfaces interne et externe de chaque marque étudiée de gouttières. MATÉRIELS ET MÉTHODES : Les gouttières ont été exposées à l’un des divers liquides colorants de l’alimentation courante (thé, café, vin rouge et cola) ou à une solution de contrôle formée d’un gel de remplacement salivaire Biotène® Oral Balance. Les trois marques évaluées étaient Invisalign®, ClearCorrect® et Minor Tooth Movement®. Après leur immersion de douze heures ou de sept jours, les mêmes gouttières étaient nettoyées pendant quinze minutes avec soit les cristaux Invisalign®, soit le bain Cordless Sonic Cleaner combiné avec un comprimé Retainer Brite®. Les données de colorimétrie étaient obtenues à l’aide d’un numériseur calibré et du logiciel Adobe Photoshop® en utilisant l’espace chromatique CIELAB pour comparer les changements de coloration (E) entre les divers moments à l’étude. Les paramètres L*, a*, b* étaient mesurés au temps initial (T0), après douze heures d’immersion (T1), après sept heures d’exposition (T2) et après nettoyage (T3). Les deltas E étaient ensuite convertis en unités du National Bureau of Standards (NBS) pour faciliter l’interprétation clinique des données. Selon la section, les analyses statistiques employées (test de Levene, ANOVA, méthode de Brunner-Langer, test de Tukey ou test-t) permettaient d’évaluer les interactions entre les trois marques entre elles ou entre les marques et les nettoyeurs. Une valeur de p < 0,05 était considérée statistiquement significative. RÉSULTATS ET DISCUSSION: Les résultats suggèrent qu’une exposition de douze heures au café pour les aligneurs Invisalign® engendre un changement de couleur statistiquement significatif par rapport aux deux autres marques. Il en est de même pour une durée identique d’immersion dans le vin rouge ; les coquilles Invisalign® présentent un changement de teinte statistiquement significatif par rapport à ses compétiteurs. Après sept jours d’exposition au café ou au vin rouge, les coquilles de la marque Invisalign® ont aussi des changements de coloration statistiquement significatifs par rapport aux deux autres marques, mais plus prononcés qu’après douze heures. Le thé noir engendre des changements de couleur importants au niveau clinique chez les trois marques après sept jours d’exposition sous forme de taches extrinsèques. Les deux méthodes de nettoyage étudiées présentent un potentiel clinique de retrait de taches accru pour celles extrinsèques du thé noir par rapport aux taches intrinsèques des autres solutions étudiées. Les résultats par spectrophotométrie à lumière infrarouge démontrent des spectres similaires pour les surfaces interne et externe de chaque marque. Or, ce n’est pas le même polymère qui est employé par chaque compagnie. Des spectres ATR-FTIR d’un matériau à base de polyuréthane sont observés pour les marques Invisalign® et ClearCorrect®. Des spectres ATR-FTIR de matériau à base de polyéthylène téréphtalate glycolisé sont plutôt représentatifs de la marque Minor Tooth Movement®. CONCLUSION: Les aligneurs de la compagnie Invisalign® sont plus susceptibles de souffrir de pigmentation par le café et le vin rouge que les deux autres marques qui ont présenté une stabilité accrue de leur coloration au contact de ces solutions. Le thé a engendré des changements de couleur extrinsèques importants chez les trois marques étudiées. / INTRODUCTION: Manufacturers of orthodontic aligners suggest that users take off removable appliances every time they consume solid foods or any drink (except water). This is to avoid a color change within the clear thermoplastic material of which they are made. Prior studies have focused on a limited set of aligners, excluding some popular American brands on the market. OBJECTIVES: The main objective of this study is to evaluate the stain resistance of the polymer forming three different American aligner brands. A secondary aim is to evaluate the stain-removal potential of two cleaning techniques for these devices. A tertiary goal is to determine the type of polymer forming the internal and external surfaces of the studied brands of aligners. MATERIALS AND METHODS: The removable appliances were exposed to different staining agents common in a regular diet (coffee, red wine, black tea and cola) or to a control solution made of a Biotene® Oral Balance saliva replacement gel. The three brands evaluated were Invisalign®, ClearCorrect® and Minor Tooth Movement®. Following exposure, the same aligners were cleaned during fifteen minutes with either the Invisalign® cleaning crystals or the Cordless Sonic Cleaner combined with a Retainer Brite® tablet. Colorimetry data was acquired via a calibrated scanner and the Adobe Photoshop® software, using a CIELAB color space approach to compare color changes (E) in aligners exposed to various media. The CIE color parameters (L*, a*, b*) of each specimen were measured before immersion (T0), after a twelve-hour exposure (T1), after a seven-day exposure (T2) and after cleaning (T3). Those color differences were then converted into National Bureau of Standards (NBS) units to facilitate the clinical interpretation. Statistics methods (Levene’s test, ANOVA, Brunner-Langer model, Tukey’s range test and t-test) were used to identify interactions between the brands themselves or between the brands and the cleaning methods. A p value < 0.05 was considered statistically significant. RESULTS AND DISCUSSION: This study suggests that an exposure of twelve hours to instant coffee affects significantly the color of the Invisalign® aligners compared to the two other brands. A twelve-hour immersion into red wine also causes a statistically significant color change for the Invisalign® devices compared to their competitors. After seven days of exposure, a more conspicuous intrinsic color change is observed in the Invisalign® aligners exposed to instant coffee and red wine. In both media, the results are statistically significant for the Invisalign® appliances compared to the ClearCorrect® and the Minor Tooth Movement® aligners. The black tea creates an important extrinsic color change in the three brands after seven days. While normal exposure conditions would not typically consist of 12 h to 7 days of continuous exposure, these data indicate that repeated, cumulative exposure may be problematic. The two cleaning methods tend to show a better efficacy in removing extrinsic stains from black tea compared to intrinsic stains of other substrates. The infrared spectrophotometry confirms that the internal and external surfaces of each studied brand of aligners were made of the same polymer. ATR FTIR spectra of polyurethane-based material are observed for the Invisalign® and the ClearCorrect® devices. However, for the Minor Tooth Movement® aligners, the ATR FTIR analysis shows that the appliances are a polyethylene glycol terephthalate polyester. CONCLUSION: The Invisalign® aligners were more prone to pigmentation from coffee and red wine than the ClearCorrect® or the Minor Tooth Movement® devices. Black tea caused important extrinsic stains on the surface of the three tested brands.