Orthodontic treatment of a nine-year-old patient with hypophosphatemic rickets diagnosed since the age of two: A case report

Hypophosphatemic rickets (HR) is a genetic disorder with various types of inheritance. It results mainly from defects in factors that control mineral ion homeostasis such as 1,25(OH)2D (Calcitriol) and FGF23 (Fibroblast Growth Factor 23). The existing bibliography regarding orthodontic treatment in patients with hypophosphatemic rickets is extremely limited. The aim of this case report is to describe the orthodontic treatment of a 9-year old Caucasian female patient suffering from HR. The patient presented a healthy late mixed dentition and periodontium. She suffered from a mild Class III maxillary skeletal pattern. There was a bilateral posterior crossbite, short lingual frenulum, a right maxillary mesioposition with a Class II subdivision on this side and a moderate space deficiency in the dental arches. The disorder was controlled by medication. In specific, patient was taking 1.5 mL of phosphate four times per day, 0.3 mL of calcitriol twice per day and 50,000 IU of Vitamin D3 on a weekly basis. Given the Class III skeletal pattern, the medical condition and the absence of relevant bibliography, it was decided to perform maxillary expansion, facemask traction and orthodontic treatment with fixed appliances. By the end of treatment, Class I canine and molar relationships were achieved, overjet and overbite were corrected and space deficiency was addressed in both arches. PAR index was 27 at the beginning of treatment and became 2 by the end of treatment (92.5% correction). The aesthetic component of IOTN was 4 and changed to 1, while the dental component used to be 5i and became 2g. With regards to retention, upper and lower fixed retainers from canine to canine and upper and lower vacuum formed appliances were used. In conclusion, a patient with controlled HR was orthodontically treated in a successful way. Orthodontic therapy was performed in a minimally invasive manner. Thus, HR does not constitute a contraindication for orthodontic treatment, when the disorder is kept under control. © 2020 CE

Anterior teeth root inclination prediction derived from digital models: A comparative study of plaster study casts and CBCT images

Background: To assess the accuracy of digital models generated using commercially available software to predict anterior teeth root inclination characteristics and compare the results to relevant data obtained from CBCT images. Material and Methods: Following sample size calculation and after application of inclusion and exclusion criteria, pre-treatment maxillary and mandibular plaster models and the corresponding CBCT scans of 31 patients attending a private orthodontic clinic were selected. The subjects were 10 males and 21 females with age range 12 to 40 years. Plaster models were scanned using the high resolution mode of an Ortho Insight 3D scanner and CBCT scans were taken using a Kodak 9500 Cone Beam 3D System machine. The teeth on the digital scans were segmented and virtual roots were predicted and constructed by the Ortho Insight 3D software. The long axes of the predicted roots and the actual roots, as segmented from the CBCT images, were computed using best-fit lines. The inter-axis angle was used to assess error in root inclination prediction by the software. Mann-Whitney and Kruskal-Wallis tests were used. Intra-examiner error was evaluated using the Bland-Altman method. Results: The maximum disparity in angle between images derived from digital models and CBCT data was almost 40 degrees (upper left canine). The upper and lower canines produced the worst results, followed by the lower lateral incisors. The upper central incisors showed the best results, although the maximum angle of difference exceeded 20 degrees (with the median around 8 degrees). Conclusions: Root morphology imaging prediction is not a primary function of this software and this study confirmed its limitation as a sole tool in routine clinical applications. At present these predictions cannot be considered accurate or reliable unless correlated clinically with a radiographic image. © Medicina Oral S. L. C.I.F

Electrostatic precipitation in a small scale wood combustion furnace

Wood combustion generates a high concentration of particulate matter emission, but most of the particulates in the exhaust gas can be filtered through an electrostatic precipitator. The objective of this paper is to model the trajectory of particulates in the exhaust chimney of a small scale wood combustion furnace with an electrostatic precipitator. The precipitator consists of a central electrode subjected to a maximum high voltage of 50 kV and an outer electrode of 180 mm diameter, ground potential. The parameters including particle size, ambient temperature, pressure, gas flow rate and the applied voltage have been varied while computing the trajectories of the particles in the chimney. The trajectories of particulates have been analyzed for different sizes of a typical wood combusting stove by taking different forces into account on particulates. The critical conditions give the trajectory of particles as a function of particulate size and applied voltage together with the function of efficiency. (C) 2011 Elsevier B.V. All rights reserved

CFD modelling of flue gas particulates in a biomass fired stove with electrostatic precipitation

The biomass fired stoves have been used in medium and large scales applications from several years and are utilizing electrostatic precipitator technology. Biomass based technologies are considered as renewable energy source and less harmful to the environment. The combustion of biomass generates a high concentration of flue gas particulates. The most of the flue gas particulates in the exhaust gas can be filtered through an electrostatic precipitator. In this work, a computational fluid dynamic (CFD) model has been developed for analysing the trajectory of particulates in a small scale domestic stove using biomass material. It is considered that electrostatic precipitator is based on an approach where both charging and precipitation of particulates takes place within the same set of electrodes. The precipitator is mounted in a vertical chimney of diameter 180 mm containing a central high voltage corona source. The model is based on biomass combustion models utilising a Eulerian-Lagrangian reference. The developed CFD model demonstrates the efficiency of the removal of charged particulates of the flue gases and also the interaction of the electric field in a semi turbulent flow together with the combination of the ion wind. Also it includes the effects of space charge within the system. In the modelling, modifications have been made to the grounded cylindrical collector of electrostatic precipitation through a re-design to include a series of inclined baffle plates for improving the particulates' collection efficiency

Thermochemical Studies of Epoxides and Related Compounds

Gas-phase heats of formation for the four butene oxide isomers are reported. They were obtained by measuring the condensed-phase heat of reduction to the corresponding alcohol using reaction calorimetry. Heats of vaporization were determined and allow gas-phase heats of formation to be obtained. The experimental measurements are compared to calculations obtained using a variety of computational methods. Overall, the G3 and CBS-APNO methods agree quite well with the experimental data. The influence of alkyl substituents on epoxide stability is discussed. Comparisons to alkenes, cyclopropanes, aziridines, thiiranes, and phosphiranes are also made. Isodesmic-type reactions were used to determine strain energies of the epoxides and related compounds with various substituents