Avaliação da densidade óssea mandibular por meio de tomografias computadorizadas: Multislice e de feixe cônico
Data
2012-09-17
Autores
Milagres , Roselaine Moreira Coelho [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Foram selecionadas dez mandíbulas humanas edêntulas maceradas, as quais foram submetidas ao exame de tomografia computadorizada multislice (TCMS) e de feixe cônico (TCFC) para realização de avaliações objetiva e subjetiva por meio da comparação da densidade óptica obtida pelos dois tomógrafos. Adicionalmente as mesmas mandíbulas foram submetidas a exame de absorciometria por dois fótons de raios X (DEXA) para avaliação da densidade mineral óssea (DMO) a qual foi expressa em g / cm2. Em cada mandíbula selecionou-se a região correspondente aos incisivos, caninos, pré-molares e molares direito e esquerdo, sendo confeccionado um guia tomográfico para cada mandíbula. As mandíbulas foram colocadas em uma caixa acrílica a qual foi preenchido com água, visando promover a atenuação dos feixes de raios X e simular a presença de tecido mole e posteriormente foram posicionadas nos tomógrafos simulando o posicionamento anatômico usualmente utilizado para a obtenção das imagens de pacientes. Após a reconstrução das imagens realizou-se a análise subjetiva nas áreas pré-determinadas, sendo o osso classificado, segundo o índice de densidade óssea proposto por Misch (1990), em D1, D2, D3 ou D4. A seguir, foi avaliada a densidade óptica pelo software dos tomógrafos para cada região pré-determinada. Para a avaliação objetiva, em ambos os tomógrafos, foi selecionada a área de osso medular, ou seja, a região de cortical interna a cortical interna da área de interesse, sem que houvesse envolvimento do osso cortical, logo acima do canal mandibular para a região de pré-molares e molares e próximo à cortical superior para as regiões de incisivos e caninos. Para comparação das densidades ópticas obtidas pelo método objetivo e subjetivo foram empregados, respectivamente, os testes estatísticos...
Ten macerated.edentulous human mandibles were selected. The mandibles were submitted to multislice computed tomography (MSCT) and cone beam computed tomography (CBCT). Objective and subjective assessments were performed to compare the optical density (OD) obtained by two tomographs. Additionally, the bone mineral density (g / cm2) of the mandibles was evaluated by Dual-Energy X-Ray Absorptiometry (DEXA). The region corresponding to the incisors, canines, premolars and molars (left and right) in each mandible was selected and a tomographic guide was created. The mandibles were placed in an acrylic box, which was filled with water to attenuate the X-ray beam and simulate the presence of soft tissue. The mandibles were placed in tomographs reproducing the anatomical position normally used to obtain images of patients. After image reconstruction, the subjective assessment of predetermined areas was performed to classify the bone according to the bone density index (D1, D2, D3 and D4) proposed by Misch (1990). Then, the bone density was also evaluated with the software of tomographs. For objective assessment, in both tomographs, it was selected the area of bone marrow without involvement of cortical bone, immediately above of the mandibular canal (premolar and molar areas) and near the superior cortical (incisor and canine areas). The OD data obtained with objective and subjective assessments were statistically analyzed (Student's t-test and Mann-Whitney test, respectively; p<0.05). It was observed that (i) the DEXA values can not be used for mandibles, since there is not a T-score determined for this region; (ii) the objective assessment performed by the “shape region” tool of CBCT software was not correlated with HU values determined by MSCT software; (iii) there is... (Complete abstract click electronic access below)
Ten macerated.edentulous human mandibles were selected. The mandibles were submitted to multislice computed tomography (MSCT) and cone beam computed tomography (CBCT). Objective and subjective assessments were performed to compare the optical density (OD) obtained by two tomographs. Additionally, the bone mineral density (g / cm2) of the mandibles was evaluated by Dual-Energy X-Ray Absorptiometry (DEXA). The region corresponding to the incisors, canines, premolars and molars (left and right) in each mandible was selected and a tomographic guide was created. The mandibles were placed in an acrylic box, which was filled with water to attenuate the X-ray beam and simulate the presence of soft tissue. The mandibles were placed in tomographs reproducing the anatomical position normally used to obtain images of patients. After image reconstruction, the subjective assessment of predetermined areas was performed to classify the bone according to the bone density index (D1, D2, D3 and D4) proposed by Misch (1990). Then, the bone density was also evaluated with the software of tomographs. For objective assessment, in both tomographs, it was selected the area of bone marrow without involvement of cortical bone, immediately above of the mandibular canal (premolar and molar areas) and near the superior cortical (incisor and canine areas). The OD data obtained with objective and subjective assessments were statistically analyzed (Student's t-test and Mann-Whitney test, respectively; p<0.05). It was observed that (i) the DEXA values can not be used for mandibles, since there is not a T-score determined for this region; (ii) the objective assessment performed by the “shape region” tool of CBCT software was not correlated with HU values determined by MSCT software; (iii) there is... (Complete abstract click electronic access below)
Descrição
Palavras-chave
Mandíbula, Tomografia, Osseointegração
Como citar
MILAGRES , Roselaine Moreira Coelho. Avaliação da densidade óssea mandibular por meio de tomografias computadorizadas: Multislice e de feixe cônico. 2012. 107 f. Tese (doutorado) - UNESP - Univ Estadual Paulista, Faculdade de Odontologia de São José dos Campos, 2012.