Relationship between the Height of Alveolar Bone Resorption and Sex and Age in Adolescents / 法医学杂志

OBJECTIVES@#To explore the relationship between the height of alveolar bone resorption and sex and age in the adolescent dentition.@*METHODS@#Multi-slice computed tomography (MSCT) was used to measure the height of alveolar bone resorption at labial, lingual, mesial and distal sites of teeth in 149 adolescents aged from 10 to 20 years. SPSS 25.0 software was used to analyze the relationship between the height of alveolar bone resorption and sex and age.@*RESULTS@#There was no significant difference in the height of alveolar bone resorption between sex (P>0.05). The height of alveolar bone resorption was positively correlated with age in all types of teeth. The model constructed by combining the alveolar bone resorption height data of four sites (y=2.569x1+3.106x2+4.108x3+1.451x4-0.082, R2max=0.756)had a better ability to infer age than that of combining two sites (y=5.942x1+4.489x2+0.612, R2max=0.706) and a single site (R2max=0.638).@*CONCLUSIONS@#The height of alveolar bone resorption is positively correlated with the age of adolescents. The combination of four sites has a stronger ability to infer the relationship between the height of alveolar bone resorption and age in adolescents and has higher accuracy in practical application.

A influência da sobre carga vertical em diferentes níveis ósseos em implantes unitários: estudo comparativo de dois sistemas de implantes / The influence of vertical load on different bone levels in single implants: a comparative study of two implant systems

Embora existe um alto índice de sucesso implantes dentários, podem ocorrer perda da osseintegração após instalação das próteses sobre implante e as causas são as periimplantites e sobre cargas oclusais. Diferentes conexõessurgiram para o melhor desempenho estético, biomecânico e para evitar perdas ósseas perimplantares. Para analisar às deformações geradas ao redor dos implantes e suas conexões, as duas metodologias utilizadas neste estudo e que apresentam resultados numéricos,foram a análise de elementos finitos e a extensometria linear.Para o teste do FEA, foi utilizado o software Rhinoceros 4.0 para obter os desenhos em 3D dos dois modelos de implantes,com o mesmo comprimento e largura, um hexágono externo HE (Titaoss® TM cortical Intraoss®, SP, Brasil) com diâmetro de 3,75 mm e comprimento de 13 mm e o segundo sendo um implante conexão interna (CM) (Titaoss® Max Cone Morse, Intraoss®, SP, Brasil). Sobre os implantes foram modelados seus abutments respectivamente, Ucla anti- rotacional com plataforma de 4.1 mm e um Pilar Cone Morse CMN com transmucoso de 0,8 mm. Ambos abutments para próteses parafusadas e foram exportados para o software de análise (ANSYS 17.0, ANSYS Inc., Houston, TX, USA) em formato STEP.Para o teste de extensometria, foram obtidos blocos de poliuretano (Poliuretano F160 ISO Axson, Cercy, França) de forma retangular com dimensões internas de 95 x 45 x 30 mm e intalados implantes Titaoss® Max Cone Morse 3,75 X 13 mm e os implantes Titaoss® TM 3,75 X 13 mm (Intraoss- SP - Brasil), e os abutments e coroas metálicas de cromo-cobalto. Formado 4 grupos: a) CM no; b) HE no, c) CM po e d) He po; em cada grupo foram instalados 4 extensômetros tangenciando cada um dos implantes, segundo mapas colorimétricos da região de maior microdeformação óssea. Na aplicação de carga, foi utilizado o dispositivo de aplicação de carga-DAC(Nishioka - Proc. 08/53071-4), com carga axial de 30 kg aplicadas por um período de 10 segundos (Mericske-Stern et al.) na fosseta central (carga axial).Resultados:1) FEA- a) Tensão de von-Mises gerada no conjunto implante/parafuso mostrou maior concentraçao de tensao no parafuso protético de ambos os grupos independente da perda óssea; b) Tensão de von-Mises gerada na região mais estressada que mostrou a possível falha na região da cabeça do parafuso de ambos os grupos independente da perda óssea; c) Tensão de von-Mises gerada no implante em secçao longitudinal foi maior concentraçao de tensao na plataforma do hexagono externo, mas, com pouca diferença no restante do corpo do implante, e d) microdeformaçao gerada no interior do bloco de poliuretano .Não foi possível notar diferenças significativas entre as diferentes conexões. Para os implantes com perda óssea é possível notar maior deformaçao ápica. 2) Na extensometria foi realizada a média da deformação gerada de cada os quatro grupos, no qual não apresentou diferenças numéricas entre os grupos. Neste estudo podemos concluir que não há diferenças significativas na microdeformação entre o grupo dos implantes CM no e HE no, com uma maior deformação CM e HE quando há presença de perda óssea(AU)

Although there is a high success rate, dental implants may lose osseintegration after implantation of prostheses on implants and the causes are peri-implantitis and occlusal loads.Different connections have emerged for better aesthetic and biomechanical performance to prevent perimplant bone loss.To analyze the deformations generated around the implants and their connections, the two methodologies used in this study and which present numerical results were the analysis of finite elements and linear extensometry.The Rhinoceros 4.0 software was used to obtain the 3D drawings of the two implant models with the same length and width, an external hexagon HE (Titaoss® TM cortical Intraoss®, SP, Brazil) with a diameter of 3.75 mm and a length of 13 mm and the second being an internal connection (CM) implant (Titaoss® Max Cone Morse, Intraoss®, SP, Brazil). The abutments were modeled on the implants, respectively, Ucla anti-rotational with 4.1 mm platform and a Morse Cone Abutment CMN with 0.8 mm transmucous. Both abutments for screwed prostheses and were exported to the analysis software (ANSYS 17.0, ANSYS Inc., Houston, TX, USA) in STEP format.For the extensometry test, rectangular polyurethane blocks (Polyurethane F160 ISO Axson, Cercy, France) with internal dimensions of 95 x 45 x 30 mm and Titaoss® Max Cone Morse 3.75 X 13 mm implants and implants were obtained Titaoss® TM 3.75 X 13 mm (Intraoss-SP - Brazil), and the abutments and metallic crowns of chromium-cobalt. Forming 4 groups: a) CM no; b) HE no; c) CM po and d) He po, each group installed 4 strain gauges tangent to each of the implants, according to colorimetric maps of the region with the greatest bone microdeformation. In the load application, the DAC load application device (Nishioka- Proc. 08 / 53071-4) was used, with an axial load of 30 kg applied for a period of 10 seconds (Mericske-Stern et al.) In the pit central (axial load).Results: 1) FEA- a) von-Mises tension generated in the implant / screw set showed a higher concentration of tension in the prosthetic screw of both groups regardless of bone loss; b) von-Mises tension generated in the most stressed region, showing possible failure in the screw head region of both groups regardless of bone loss; c) VonMises stress generated in the implant in longitudinal section was higher stress concentration in the external hexagon platform but with little difference in the rest of the implant body, and d) microdeformation generated inside the polyurethane block, it was not possible to notice significant differences between the different connections. For implants with bone loss, it is possible to notice greater apical deformation. 2) In the extensometry, the average strain generated for each of the four groups was performed, in which there were no numerical differences between the groups. In this study we can conclude that there was no difference in microdeformation between the group of CM implants and HE no, with a greater CM and HE deformation when there is bone loss(AU)

Osteodistrofia renal y trastornos del metabolismo y la mineralización ósea asociados a enfermedad renal crónica: manifestaciones en radiología / Renal osteodystrophy and disorders of bone metabolism and mineralisation associated with chronic kidney disease: radiological manifestations

Abstract. Chronic kidney disease is a public health problem worldwide, with disorders of bone mineralisation and metabolism being common problems associated with this disease, causing significant morbidity and impaired quality of life. The expression of the findings in the chronic kidney disease can be categorised based on the classification proposed by the international conference Kidney Disease: Improving Global Outcomes, that divides them into metabolic disorders of calcium and phosphorus (without findings in radiology), bone structure and composition disorders, and extra-skeletal calcifications. These conditions give characteristic radiographic patterns, such as bone resorption and sclerosis, brown tumours, osteomalacia-rickets, osteopenia, and extra-skeletal calcifications, in addition to treatment related disorders of chronic kidney failure. In this article, concepts related to metabolism disorders and bone mineralisation associated with chronic renal disease and renal osteodystrophy will be categorised and updated, showing their various manifestations in radiology.

La enfermedad renal crónica es un problema de salud pública a nivel mundial, siendo los trastornos de la mineralización y el metabolismo óseo problemas comunes asociados a esta enfermedad, que causan una importante morbilidad y un deterioro de la calidad de vida. La expresión de los hallazgos en la enfermedad renal crónica puede sistematizarse con base en la clasificación propuesta por la conferencia internacional Kidney Disease: Improving Global Outcomes, que las divide en trastornos del metabolismo del calcio y el fósforo (sin hallazgos en imágenes), alteración de la estructura y la composición del hueso, y calcificaciones extraesqueléticas. Estos trastornos otorgan patrones radiológicos característicos, como son la resorción y esclerosis ósea, tumores pardos, osteomalacia-raquitismo, osteopenia y calcificaciones extraesqueléticas, además de los trastornos asociados al tratamiento de la falla renal crónica. En el presente artículo se sistematizarán y actualizarán los conceptos relacionados con los trastornos del metabolismo y la mineralización ósea, asociados a la enfermedad renal crónica y la osteodistrofia renal, mostrando sus diversas manifestaciones en radiología.

Validação de dois métodos de análise volumétrica e linear óssea em tomografia computadorizada multislice 3D / Validation of two methods of volumetric and linear bone analysis in 3D multislice computed tomography

O objetivo deste trabalho foi avaliar a acurácia e reprodutibilidade de medidas ósseas lineares e volumétricas através do processamento de dados obtidos por tomografia computadorizada multislice por dois softwares Amira6® e CoDiagnostiX®. O material da pesquisa foi composto de uma mandíbula seca. Foi feita uma tomada tomográfica da peça intacta e uma segunda tomada com a mandíbula adicionada de quatro enxertos em bloco de diferentes dimensões, além de quatro desgastes. Os dados obtidos foram então processados através dos dois softwares por 3 examinadores, previamente calibrados, duas vezes cada um. As medidas físicas lineares dos blocos foram obtidas com um paquímetro digital e as de volume dos blocos e desgastes pela técnica do deslocamento em água em um cilíndro milimetrado. O volume dos desgastes foi obtido por preenchimento dos mesmos com resina bisacrílica de uma moldagem feita com a mandíbula intacta sobreposta na mesma com os desgastes, estes dados foram processados apenas pelo software Amira6® que permite a sobreposição de imagens 3D. A acurácia das medidas lineares e de volume foi avaliada pela comparação com o padrão ouro através do teste-T de Student e ANOVA. Os resultados mostraram que não houve diferença estatística significante nas medidas lineares e volumétricas obtidas entre os dois softwares e quando comparados individualmente com o padrão ouro.

The aim of this study was to evaluate the accuracy and reproducibility of linear and volumetric bone measurements through data processing obtained by multislice computed tomography for two softwares: Amira6® and CoDiagnostiX®. The research material was composed of a dry mandible. A first tomography was made and then the jaw was added with four bone block grafts of different sizes and four wears were made in the chin area. The data were then processed twice using the two softwares by 3 examiners previously calibrated. Linear physical measurements of the blocks were obtained with a digital caliper and the volume of the blocks and wears by water displacement in a calibrated cylinder. The volume of each wear was obtained by filling the same with bis-acrylic composite of a matrix made with the jaw intact superimposed on it, these data were processed only by Amira6® software that allows 3D images overlap. The accuracy of linear and volumetric measurements was evaluated by comparison to the gold standard by Student T-test and ANOVA. The results showed no statistically significant difference in linear and volumetric measurements between the two softwares and individually when compared with the gold standard.

Comparação das imagens radiográficas digitais e convencionais em reabsorções ósseas periodontais / Comparison of the conventional and digital radiographic image in periodontal bone resorption

Objetivo: Analisar os defeitos ósseos periodontais, pela comparação das imagens digitais (utilizando as ferramentas do Digora fmx 2.5) com as convencionais na angulação de -10, 0 e +10º, pela análise de três observadores. Métodos: Para obtenção das imagens foi utilizado um aparelho de Raio-X convencional, com padronização da tomada radiográfica, pela utilização do posicionador do tipo Rinn® e moldagem de resina das superfícies oclusais dos dentes a serem radiografados, nas três incidências radiográficas utilizadas. O contraste e a densidade foram padronizados no emprego do sistema digital Digora, com as exposições dos Raio-X adequadas a cada região. As radiografias convencionais foram realizadas com películas do tipo Insight da marca Kodak nº 2. As imagens digitais foram analisadas no monitor do computador por meio do software do Digora 2.5, utilizando a ferramenta para alterações das imagens padrão, 3D e negativa e as convencionais observadas em um negatoscópio apropriado. Resultados: O resultado estatístico demonstrou diferença significativa na análise entre os observadores, quanto às imagens obtidas, as digitais produziram imagens consideradas de qualidade inferior sem alterações das ferramentas em comparação à radiografia convencional e quando a imagem digital era alterada (brilho, contraste, 3D), a qualidade aumentava significativamente, sendo comparável à produzida pela película convencional. Quanto ao ângulo de incidência do feixe dos Raio-X, não foram detectadas diferenças significativas entre os mesmos, ocorrendo o mesmo quanto ao lado radiográfico. Conclusão: Os métodos radiográficos convencionais e digitais (quando da utilização das ferramentas para alteração das imagens) não demonstraram diferenças estatísticas na efetividade da quantificação dos defeitos ósseos periodontais.

Objective: To assess periodontal bone defects, comparing the digital images (using the tools of Digora® fmx 2.5) with the conventional angle of -10, 0 and 10 degrees, through the three evaluators analysis. Methods: To obtain the images we used a conventional X -ray machine with standardized radiography, using the positioner type Rinn and resin molding of the occlusal surfaces of teeth to be X-ray in three radiographic. The contrast and density were standardized in the use of digital Digora with X-ray exposures appropriate to each region. The radiographs were performed with films Kodak Insight brand 2. Digital images were analyzed on the computer monitor through Digora 2.5 software, using the tool to change the default images, 3D and conventional negative and observed in an appropriate light box. Results: The results of statistical analysis showed significant difference between the observers in the images obtained, the digital images produced poor quality images without changing tools in comparison to conventional radiography and when the digital image was changed (brightness, contrast, 3D), the quality increased significantly, as compared to that produced by conventional film. As the angle of incidence of the x-rays beam, there were no significant differences between them, the same happened on the radiographic side. Conclusion: The conventional and digital radiographic methods (when using the tools to change the images), showed no statistical differences in the effectiveness of the quantification of periodontal bone defects.

Evaluation of radiographic predictors to assess the rate of mandibular residual ridge resorption.

Sixty healthy clinical edentulous patients (thirty male and thirty female) were chosen for the study. Panoramic and lateral cephalometric radiographs were taken of each patient. The amount of bone loss was estimated from the panoramic radiographs as per the formula proposed by Wical and Scoop. The rate of mandibular residual resorbed ridge (RRR) expressed as percentage of bone loss per year was then computed. The correlation between the mandibular RRR and gonial cortical thickness and the percentage of cortical bone at the symphysis was tested. These parameters were also compared between the male and female patients. The rate of mandibular RRR, expressed as percentage of bone loss per year, was found to be indirectly correlated with the cortical thickness at gonion as measured from the panaromic and the lateral cephalometric radiographs. The values of students 't' test for mean differences between the female and the male patients with respect to the rate of mandibular RRR and the cortical thickness at the gonion were found to be statistically significant.

Biochemical versus radiological studies for early detection of steroid-induced bone depletion in children

To examine the early effects of the usual dose of prednisone treatment [1-2mg/kg / day] for about one month on bone depletion in different pediatric diseases. Bone mineral density [BMD] was measured using quantitative computed tomography [QCT]. Bone formation was quantified by measurement of serum osteocalcin, alkaline phosphatase, calcium and phosphorus. Bone resorption was measured by urinary excretion of calcium, phosphorus and hydroxyproline. BMD was significantly reduced in the steroid treated group [P < 0.05]. As regards bone formation parameters, only osteocalcin was significantly reduced [P < 0.05] while other parameters were not different. Urinary hydroxyproline and phosphorus as parameters of bone resorption were significantly elevated [P < 0.01 and < 0.05 respectively] with no change in urinary calcium excretion. No correlation has been found between BMD and any of the laboratory markers. One month treatment with prednisone in the usual dose is associated with some degree of bone depletion and although osteocalcin and hydroxyproline values were significantly different in the steroid treated group, yet they are weak substitutes for radiological studies [bone densitometry] in monitoring bone density in these patients