Objective: Clinicians make numerous decisions when 3D printing models for fabrication of thermoformed appliances, including printing solid or hollow models. While hollow models can reduce resin use, models intended for thermoformed appliance fabrication must be printed with sufficient thickness to withstand thermoforming. The aim of the study was to determine for hollow 3D printed orthodontic models if there is an effect of shell thickness on the dimensional accuracy of retainers thermoformed upon them as compared with solid models and, if so, to identify the minimum shell thickness that ensures dimensional accuracy of the thermoformed retainer under the conditions investigated.
View Article and Find Full Text PDFRadiation induces ovarian damage and accelerates reproductive aging. Inbred mouse strains exhibit differential sensitivity to lethality induced by total body irradiation (TBI), with the BALB/cAnNCrl (BALB/c) strain being more sensitive than the 129S2/SvPasCrl (129) strain. However, whether TBI-induced ovarian damage follows a similar pattern of strain sensitivity is unknown.
View Article and Find Full Text PDFAm J Orthod Dentofacial Orthop
August 2019
Introduction: Many variables can affect the accuracy of 3D-printed orthodontic models, and the effects of different printing parameters on the clinical utility of the printed models are just beginning to be understood. The objective of this study was to investigate the effect of print layer height on the assessment of 3D-printed orthodontic models with the use of the American Board of Orthodontics Cast-Radiograph Evaluation grading system.
Methods: Twelve cases were scanned using a desktop model scanner and 3D-printed using a stereolithography-based printer at three different layer heights (25, 50, and 100-μm; n = 12 per group).
Introduction: Emerging workflows in orthodontics enable automated analysis of digital models and production of physical study models from digital files for the evaluation of treatment outcomes. The objective of this study was to compare the automated assessment of digital orthodontic models and the hand grading of 3D-printed models with the use of the American Board of Orthodontics cast-radiograph evaluation (ABO CRE) system.
Methods: Plaster models from 15 cases were scanned with the use of a desktop model scanner to create digital models from which physical models were produced with the use of a stereolithography-based 3D printer.
Purpose: To evaluate if pre-treatment with silver diamine fluoride (SDF) adversely affects the bond strength of orthodontic brackets to enamel.
Methods: 30 extracted non-carious permanent molar teeth were embedded in acrylic resin cylinders with buccal surfaces exposed and randomly divided equally into two groups. The experimental enamel surfaces were treated with 38% SDF applied for 1 minute between phosphoric acid etch and metal orthodontic bracket bonding with Transbond XT Light Cure Adhesive.
Objectives:: To evaluate and compare the dental and skeletal changes with conventional and miniscrew-supported maxillary expansion appliances in adolescents.
Materials And Methods:: Forty patients were divided into two groups, with one group receiving a tooth-borne expander and the other group receiving an expander supported by four miniscrews (bone-borne). Multiplanar coronal and axial slices obtained from cone-beam computed tomography images were used to measure the changes in transverse skeletal widths, buccal bone thickness, tooth inclination, and root length.
In order to effectively treat obesity, it must be better understood at the cellular level with respect to metabolic state and environmental stress. However, current two-dimensional (2D) in vitro cell culture methods do not represent the in vivo adipose tissue appropriately due to the absence of complex architecture and cellular signaling. Conversely, 3D in vitro cultures have been reported to have optimal results mimicking the adipose tissue in vivo.
View Article and Find Full Text PDFNon-alcoholic fatty liver disease (NAFLD) is a family of liver diseases associated with obesity. Initial stage of NAFLD is characterized by a fatty liver, referred to as steatosis, which progresses in some individuals to non-alcoholic steatohepatitis (NASH) and liver failure. In order to study and treat the many liver diseases such as NAFLD, an improved in vitro cellular model is needed.
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