Superimposition of 3D maxillary digital models using open-source software

Abstract Historically, whether for research purposes or clinical monitoring, orthodontic evaluation of dental movements has been done using plaster study models and two dimensional (2D) radiographs. However, new frontiers for the diagnosis, planning and outcome assessment of orthodontic treatments have arisen, due to the revolutionary digital tools which enable a three dimensional (3D) computerized analysis of dental movements by means of digital models. However, the software for 3D analysis are often costly, resulting in limited access to orthodontists. The present study aims to describe, through a clinical case presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics, a method for the superimposition of maxillary digital models using an open-source software to evaluate dental movements.

Resumo Historicamente, a avaliação ortodôntica da movimentação dentária, seja com finalidade de pesquisa, seja para monitoramento clínico, tem sido feita por meio de modelos de estudo em gesso e radiografias em duas dimensões (2D). Entretanto, com o desenvolvimento da Ortodontia digital, novas fronteiras para o diagnóstico, planejamento e avaliação dos resultados dos tratamentos ortodônticos têm surgido. Os modelos digitais possibilitam uma análise computadorizada da movimentação dentária nas três dimensões (3D); porém, os softwares usados para as análises 3D geralmente são onerosos e de limitado acesso aos clínicos. O presente artigo visa descrever um método de sobreposição de modelos 3D da arcada dentária superior utilizando um software de livre acesso para avaliar a movimentação dentária, ilustrado por um caso clínico apresentado ao Board Brasileiro de Ortodontia e Ortopedia Facial.

Síndrome de solapamiento: polimiositis-esclerodermia. Presentación de un caso / Polymyosis-Sclerosis Overlap Syndrome. Case report and review of literature

Introducción: en el síndrome de solapamiento o superposición existen simultáneamente manifestaciones clínicas o serológicas de dos o más enfermedades autoinmunes sistémicas. Afectan al 5 por ciento de la población con predominio en mujeres. Presentación del Caso: hombre de 48 años, sin antecedentes patológicos personales. Acude con dolor en ambas manos, inflamación en las articulaciones metacarpo e interfalángicas proximales, bilateral y simétrica, acompañada de rigidez matinal que duraba casi todo el día desde hace 4 meses. Se le diagnostica artritis reumatoidea y se inicia tratamiento que abandonó. Luego aparece un cuadro que es interpretado como un solapamiento por lo que es ingresado con un cuadro clínico florido. En los exámenes de laboratorio: las transaminasas, la creatín fosfoquinasa, el lactato deshidrogenasa, se encontraban elevadas. Por la clínica y los complementarios se diagnosticó Síndrome de Solapamiento de polimiosistis-esclerodermia. Se comenzó tratamiento con inmunosupesores. El paciente evolucionó desfavorablemente y falleció. Discusión: el diagnóstico de este caso se realizó por las manifestaciones clínicas como fascie esclerodérmica, signo de sal y pimienta, fibrosis de predominio distal en ambas manos, telangiectasias peribucales. Los diagnósticos diferenciales son las enfermedades autoinmunes sistémicas cuando se presentan como cuadros únicos. El tratamiento de primera línea y el pronóstico dependen de las enfermedades que se solapen(AU)

Introduction: In the syndrome of overlap or overlap there are simultaneously clinical or serological manifestations of two or more systemic autoimmune diseases. They affect 5 percent of the population with predominance in women. Case Presentation: A 48-year-old man with no personal pathological history. He came with pain in both hands, inflammation in the metacarpal and interphalangeal proximal joints, bilateral and symmetrical, accompanied by morning stiffness that lasted almost all day for 4 months. He was diagnosed with rheumatoid arthritis and started treatment that he abandoned. Then a picture appears that is interpreted as an overlap so it is entered with a florid clinical picture. In laboratory tests: transaminases, creatine phosphokinase, lactate dehydrogenase, were elevated. Clinical and complementary diagnosis of Polymyosis-Sclerosis Overlap Syndrome was diagnosed. Treatment with immunosupers was started. The patient evolved unfavorably and died. Discussion: The diagnosis of this case was made by clinical manifestations such as sclerodermic fascia, salt and pepper sign, predominantly distal fibrosis in both hands, perioral telangiectasias. Differential diagnoses are systemic autoimmune diseases when presented as single frames. First-line treatment and prognosis depend on overlapping diseases(AU)

Application of superposition theorem in teaching transistor amplifier circuit / 中华医学教育探索杂志

Transistor amplifier is the key and difficult points in the teaching of medical electronics,however,most of the teaching materials on this content is insufficient.Meanwhile,medical students have little knowledge of engineering,so it is difficult for them to grasp the related knowledge.We introduced ‘ superposition theorem’ into the relevant teaching.Teaching practice proved that this reform made it easier for medical students to have an in-depth understanding of the content and better teaching effect was achieved.

Study and Analysis of Method for Extracting SEP / 中国医学物理学杂志

Objective: To study the method of extracting somatosensory evoked potential better. Methods: This article com-pares an auto-reference, auto-correlative and adaptive interference cancellation theories and techniques (AAA-ICT) used to the single trial of somatosensory evoked potential (SEP) with the traditional superposition averaging. Results: By the intensive study and analysis of the somatosensory evoked potentials from the 80 human subjects whose nervous systems are normal, We can find that the traditional superposition averaging method has its reasonable connotation on the extraction of SEP except the inevitable defects. Conclusions: Meanwhile the AAA-ICT avoids its defects. R implements another jump for the SEP extrac-tion method and has a good clinical application value.

Commissionning of Dynamic Wedge Field Using Conventional Dosimetric Tools / 대한치료방사선과학회지

PURPOSE: To collect beam data for dynamic wedge fields using conventional measurement tools without the multi-detector system, such as the linear diode detectors or ionization chambers. MATERIALS AND METHODS: The accelerator CL 2100 C/D has two photon energies of 6MV and 15MV with dynamic wedge angles of 15o, 30o, 45o and 60o. Wedge transmission factors, percentage depth doses(PDD's) and dose profiles were measured. The measurements for wedge transmission factors are performed for field sizes ranging from 4x4cm2 to 20x20cm2 in 1-2cm steps. Various rectangular field sizes are also measured for each photon energy of 6MV and 15MV, with the combination of each dynamic wedge angle of 15o, 30o, 45o and 60o. These factors are compared to the calculated wedge factors using STT(Segmented Treatment Table) value. PDD's are measured with the film and the chamber in water phantom for fixed square field. Converting parameters for film data to chamber data could be obtained from this procedure. The PDD's for dynamic wedged fields could be obtained from film dosimetry by using the converting parameters without using ionization chamber. Dose profiles are obtained from interpolation and STT weighted superposition of data through selected asymmetric static field measurement using ionization chamber. RESULTS: The measured values of wedge transmission factors show good agreement to the calculated values. The wedge factors of rectangular fields for constant Y-field were equal to those of square fields. The differences between open fields' PDDs and those from dynamic fields are insignificant. Dose profiles from superposition method showed acceptable range of accuracy(maximum 2% error) when we compare to those from film dosimetry. CONCLUSION: The results from this superposition method showed that commissionning of dynamic wedge could be done with conventional dosimetric tools such as point detector system and film dosimetry winthin maximum 2% error range of accuracy.

Modeling and dynamic analysis of stretcher bed on ambulance based on virtual prototyping technology / 医疗卫生装备

Objective To obtain the dynamic characteristics of the stretcher bed without absorber, and to optimize the absorber. Methods Pro/E and ADAMS were used to build the dynamic model of the stretcher bed on ambulance. The principle of random sine wave superposition and Visual Basic language were used to produce time-domain pavement roughness which could stimulate the model. The system was analyzed. Results The curve of vertical acceleration in time and frequency domain and the RMS of vertical acceleration without absorber were obtained by simulation., and a reasonably suited pair of stiffness and damping coefficient was found to reduce the vibration intensity. Conclusion The inherent frequency of the stretcher bed is 2.7Hz, which is out of the sympathetic vibration area of decubital body. Through adjusting and optimizing the stiffness and damping of vibration reduction equipment, the stretcher bed is more comfortable.