Severe secondary hyperparathyroidism and panoramic radiography parameters.

OBJECTIVES: Renal osteodystrophy (RO) are skeletal abnormalities seen in patients with secondary hyperparathyroidism (SHPT). This study aims to evaluate the effects of RO using panoramic radiography parameters. Furthermore, the correlation between these parameters and parathyroid hormone (PTH) levels was tested. MATERIALS AND METHODS: Qualitative (mandibular cortical index/trabecular bone pattern) and quantitative parameters (mental index/calcification and resorption foci) were applied from panoramic radiographs of chronic kidney disease (CKD) patients and controls. Frequency distribution and descriptive analysis were used to compare the results of both groups. Spearman's correlation coefficient evaluated the correlation between serum PTH levels of CKD patients and the radiographic parameters. Intra- and interobserver agreement was tested using the intraclass correlation coefficient and kappa index. RESULTS: Intra- and interobserver agreement was respectively excellent (0.81-1.00) and good (0.61-0.80). Qualitative parameters demonstrate significant difference compared with the control group. Mean mental index was lower in patients with CKD (3.17 ± 1.35 mm), but the difference was not significant. Calcification/resorption foci (3.63 ± 2.07) of CKD patients were significantly more present than in the control group (p = 0.0001). PTH levels were correlated with mental index, mandibular cortical index and trabecular bone pattern (respectively, 0.0034, 0.0315, and 0.0370). CONCLUSIONS: RO presented a number of characteristic bone metabolic effects in the jaws that could be observed on panoramic radiographs. Radiographs of CKD patients demonstrate significantly more calcification and resorption. CLINICAL RELEVANCE: The mental index, mandibular cortical index, and trabecular bone pattern are good parameters for evaluating the effects of RO on severe secondary hyperparathyroidism.

Comparative analysis between three methods of bone estimating age in individuals with down syndrome by mode of the hand and wrist ray.

The wrist and hand region has been the most commonly used for estimating age and osseous development due to the great number of ossification centers. The aim was to determine which method, Tanner & Whitehouse's (TW3), Greulich & Pyle's (GP) or Eklof & Ringertz's, more closely relates to the chronological age in subjects with Down syndrome with chronological ages between 61 and 180 months, using wrist and hand radiographs. The sample consisted of 85 radiographs, 52 of males and 33 of females. Eklof & Ringertz's method was computerized (Radiomemory). Greulich & Pyle's atlas was used and compared with the wrist and hand radiographs. For the TW3 method, 13 ossification centers were evaluated; for each one of them, there are seven or eight development stages to which scores are assigned; these scores are then added and the results are transformed into osseous age values. No statistically significant differences were observed between the male and female genders for methods TW3 and GP, contrasting with the observed differences for the Eklof & Ringertz method. Correlation (r2) between osseous and chronological ages was 0.8262 for TW3 and 0.7965 for GP, while for the method of Eklof & Ringertz, it was 0.7656 for females and 0.8353 for males. The author concluded that the osseous age assessment method that better related to the chronological age was the TW3, followed by Greulich & Pyle's and Eklof & Ringertz's.

Evaluation of simulated external root resorptions with digital radiography and digital subtraction radiography.

INTRODUCTION: Root resorption can cause damage in orthodontic patients. Digital subtraction radiography (DSR) is a useful resource for the detection of mineral losses. The purpose of this study was to compare the efficacy of digital radiography (DR) and DSR in detecting simulated external root resorption. Examiner agreement between the 2 techniques was also evaluated. METHODS: Root resorptions of various sizes were simulated on the apical and lingual aspects of 49 teeth from 9 dry human mandibles. The teeth were radiographed in standardized conditions. The radiographs were registered with Regeemy Image Registration and Mosaicking (version 0.2.43-RCB, DPI-INPE, São José dos Campos, São Paulo, Brazil) and subtracted with Image Tool (University of Texas Health Science Center at San Antonio). The subtracted images and the digital radiographs were evaluated by 3 oral radiologists. RESULTS: No statistically significant differences were found for the methods in the detection of apical root resorptions, independently from lesion size, and of lingual resorptions of 1.2 mm or greater. DSR was significantly better than DR for detection of lingual resorptions up to 1 mm. Resorptions less than 0.5 mm were not precisely detected by either method. DSR provided better intraexaminer and interexaminer agreement than did DR. CONCLUSIONS: Both methods are precise for detection of apical root resorptions as small as 0.5 mm and lingual resorptions of 1 mm or more. However, DSR frequently performed better than did DR.

Effects of different swimming exercise intensities on bone tissue composition in mice: a Raman spectroscopy study.

OBJECTIVE: Raman spectroscopy was employed to evaluate the effect of different swimming intensities on femoral bone composition in an animal model. BACKGROUND DATA: Intense swimming exercise may affect bone mineralization, and Raman technique has been shown to be effective in evaluating tissue composition (phosphate minerals and carbonate apatites - bands at 960 and 1170 cm(-1), as well as collagen matrix - amide I band at 1660 cm(-1)). MATERIALS AND METHODS: Eighteen female Swiss Webster mice were separated into three groups (n = 6 per group) of sedentary (SED), and swimming with an intensity of 40% (PT-40) and 80% (PT-80) of the maximum load, with 6 weeks of training. Near-infrared Raman spectra (830 nm wavelength and 80 mW laser power) were obtained with a dispersive Raman spectrometer using a CCD camera and imaging spectrograph with 30-s integration time. Spectra were collected in the medial and lateral diaphysis of the femur and principal components analysis (PCA) was employed to extract features of the Raman bands of bone and to perform quantitative analysis. RESULTS: PC1 vector resembles Raman spectra and carries information about apatite minerals and some contribution from organic matrix. A statistically significant difference was found in the PC1 scores (ANOVA, p < 0.05), indicating lower mineral concentrations in the femur in both the PT-40 and PT-80 groups compared to the SED group. These results corroborated with the radiographic assessment of bone density. CONCLUSION: Raman technique associated with PCA statistics showed that intense swimming exercise may affect bone mineralization and remodeling in a mouse model of training.

Skeletal age of individuals with Down syndrome.

The aim of this study was to assess the skeletal age of Brazilian individuals with Down syndrome (DS) using the method of Greulich and Pyle. Forty subjects with DS between the ages of 6 and 16 years were studied and compared to a control sample of children without DS. The statistical analysis showed that at the age of 7 years the skeletal age (SA) of the individuals with DS was delayed in relation to their chronological age (CA) (SA < CA). On the other hand, at the age of 15 years, their SA was advanced in relation to their CA (SA > CA). An evaluation of the results suggests that the period of adolescent development for individuals with DS was shorter. These individuals reach the completion of bone maturation earlier compared to individuals without DS.

Importancia y aplicaciones del sistema de Tomografia Computarizada Cone-Beam (CBCT) / Importance and aplications of Cone-Beam Computed Tomography (CBCT)

Actualmente el sistema de tomografia computarizada Cone-beam(CBTM) puede ser empleada en el mundo médico y odontologico. Este sistema tiene como principio un algoritmo que corrige las deformidades e inestabilidades de las imágenes tomográficas computarizadas posibilitando mejor visualización y mayor exactitud en imágenes de tumores o áreas de interés profesional. Desta forma, el profesional consigue localizar fácilmente, con un minino de error, el local de interés para tratamientos quirúrgicos, radioterápicos y otros, permitiendo un mejor planeamento a sus pacientes

The cone-beam computed tomography (CBCT) has been applied to Dentistry and Medicine all over the world. This system is based on an algorithm which corrects the deformities and instabilities of the tomographic images, providing a more precise visualization of tumors and regions of interest. Therefore, the professional will easily localize, with a minimum degree of mistake, the target for surgical and radiotherapic treatments, among others, and achieve a better treatment plan for the patient

Atualmente o sistema de tomografia computadorizada Cone-beam (CBCT) vem sendo empregado em todo o mundo na Medicina e na Odontologia. Este sistema baseia-se em um algoritmo que corrige as deformidades e instabilidades das imagens tomográficas computadorizadas possibilitando assim visualizar com maior precisão as imagens de tumores ou áreas de interesse para o profissional. Desta forma o profissional consegue localizar facilmente, com mínimo de erro, o alvo de interesse para tratamentos cirúrgicos, radioterápicos, entre outros; permitindo um melhor plano de tratamento aos seus pacientes