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1.
Bone ; 179: 116984, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38013020

RESUMO

The age-related maturation of the human midpalatal suture is challenging to predict, but critical for successful non-surgical rapid maxillary expansion (RME). While cone-beam computed tomography (CBCT) can be used to categorize the suture into stages, it remains unclear how well the stages predict the actual micromorphology of the palate. To address this clinically relevant question, we used CBCT together with three-dimensional micro-computed tomography (µCT) analysis on 24 human palate specimens from individuals aged 14-34 years. We first classified the specimens into stages (A-E) using CBCT images and then correlated the results with our comprehensive µCT analysis. Our analysis focused on several factors, including bone volume fraction (BV/TV), sutural width, volume, interdigitation, ossification, and their associations with age, CBCT stage, and sex. Our µCT analysis revealed a decrease in sutural width and volume after the age of 20 years, accompanied by sutural closure beginning in the palatal segment. The overall rate of ossification remained low but increased after the age of 20 years. No significant differences were found between males and females. Importantly, we also found no correlation between individual age and CBCT stages. Furthermore, there was no association between CBCT stages and patalal suture volume, ossification and interdigitation. Taken together, our findings cast doubt on the reliability of CBCT stage as a means of predicting skeletal maturity of the palatal suture, as it appears to lack the precision required to accurately assess the true micromorphology of the palatal suture. Future investigations should explore whether alternative CBCT parameters may be more useful in addressing the challenging question of whether RME requires surgical bone weakening.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Masculino , Feminino , Humanos , Reprodutibilidade dos Testes , Microtomografia por Raio-X , Suturas Cranianas/diagnóstico por imagem , Palato , Suturas , Maxila
2.
Artigo em Inglês | MEDLINE | ID: mdl-23706921

RESUMO

OBJECTIVE: To compare the diagnostic value of six intraoral digital receptors and a cone beam computed tomography scanning system for detection of voids in root fillings. METHODS: Sixty-seven root-filled roots with oval and ribbon-shaped canals were included. Three standardized radiographic examinations were performed for each root with six intraoral digital receptors. Further, the roots were examined using CBCT. Four observers measured the extension of voids in all images. The true extension of voids was recorded in cross-sectional images from micro-computed tomography scans (micro-CT). The proportion of voids observed in the radiographic image validated against micro-CT was calculated for each system. RESULTS: All intraoral receptors underestimated the extension of voids, and few false positives were recorded. CBCT resulted in a higher proportion of correctly observed voids, but with several false-positive recordings. CONCLUSIONS: The diagnostic value differed little among the six intraoral systems. CBCT overestimated in many cases the proportion of voids in root fillings.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Cavidade Pulpar/diagnóstico por imagem , Radiografia Dentária Digital/métodos , Obturação do Canal Radicular , Raiz Dentária/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X/métodos
3.
Artigo em Inglês | MEDLINE | ID: mdl-23159120

RESUMO

OBJECTIVES: Investigations of cone beam computed tomography (CBCT) for bisphosphonate-related osteonecrosis of the jaw (BRONJ) imaging are rare. The purpose of this study was to investigate the prevalence of typical radiological findings of BRONJ in CBCT. METHODS: Twenty-seven CBCTs of BRONJ sites were assessed on the basis of the radiological findings (cancellous bone destruction, cortical bone erosion, sequestration, osteosclerosis, and periostal bone formation) and put in relation to the severity of the BRONJ sites. RESULTS: Cancellous bone destruction and cortical bone erosion were the most common findings. Occurrence seems to decrease with decreasing BRONJ severity. Sequestration and osteosclerosis were less frequent and could be seen across all stages. Periosteal bone formation occurred in high-stage BRONJ only. CONCLUSION: Cancellous bone destruction, cortical bone erosion, sequestration, and osteosclerosis can be seen across all stages and prevalence seems to decrease with decreasing severity of BRONJ. The occurrence of periosteal new bone formation seems to start in high-stage BRONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Humanos , Masculino , Prevalência
4.
Am J Orthod Dentofacial Orthop ; 138(2): 133.e1-7; discussion 133-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20691344

RESUMO

INTRODUCTION: The aim of this study was to compare the presence of alveolar defects (dehiscence and fenestration) in patients with Class I and Class II Division 1 malocclusions and different facial types. METHODS: Seventy-nine Class I and 80 Class II patients with no previous orthodontic treatment were evaluated using cone-beam computed tomography. The sample included 4319 teeth. All teeth were analyzed by 2 examiners who evaluated sectional images in axial and cross-sectional views to check for the presence or absence of dehiscence and fenestration on the buccal and lingual surfaces. RESULTS: Dehiscence was associated with 51.09% of all teeth, and fenestration with 36.51%. The Class I malocclusion patients had a greater prevalence of dehiscence: 35% higher than those with Class II Division 1 malocclusion (P <0.01). There was no statistically significant difference between the facial types. CONCLUSIONS: Alveolar defects are a common finding before orthodontic treatment, especially in Class I patients, but they are not related to the facial types.


Assuntos
Perda do Osso Alveolar/etiologia , Processo Alveolar/patologia , Má Oclusão Classe II de Angle/complicações , Má Oclusão Classe I de Angle/complicações , Técnicas de Movimentação Dentária/efeitos adversos , Adulto , Perda do Osso Alveolar/patologia , Remodelação Óssea , Tomografia Computadorizada de Feixe Cônico , Face/anatomia & histologia , Ossos Faciais/anatomia & histologia , Humanos , Má Oclusão Classe I de Angle/diagnóstico por imagem , Má Oclusão Classe I de Angle/terapia , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Mandíbula , Maxila , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-18602314

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effective doses from analog film, panoramic digital, and panoramic scout for cone-beam computerized tomography (CT). STUDY DESIGN: Three different types of Veraviewepocs machines were investigated: Veraviewepocs Conventional, Veraviewepocs Digital, and Veraviewepocs 3D (Morita, Kyoto, Japan). Organ absorbed doses were measured using an anthropomorphic phantom loaded with thermoluminescent dosimeters (TLD 100H) at 16 sites located in sensitive organs. The resulting effective organ doses (muSv) were compared by descriptive statistics. RESULTS: The highest value (5.2 muSv) was for Veraviewepocs Conventional. The Veraviewepocs Digital (2.7 muSv) and Veraviewepocs 3D (2.95 muSv) presented low effective doses in the same range. CONCLUSIONS: The panoramic digital system delivered the least radiation dose. The use of the panoramic scout for cone-beam CT was marginally higher in dose than its 2D counterpart.


Assuntos
Tomografia Computadorizada de Feixe Cônico/instrumentação , Radiografia Panorâmica/instrumentação , Adulto , Carga Corporal (Radioterapia) , Humanos , Imageamento Tridimensional/instrumentação , Masculino , Imagens de Fantasmas , Radiografia Dentária Digital/instrumentação , Radiometria , Filme para Raios X
6.
Am J Orthod Dentofacial Orthop ; 133(5): 640.e1-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18456133

RESUMO

INTRODUCTION: Because of the advantages and possibilities of cone-beam computed tomography (CBCT), orthodontists use this method routinely for patient assessment. The aim of this study was to compare the radiation doses for conventional panoramic and cephalometric imaging with the doses for 2 different CBCT units and a multi-slice CT unit in orthodontic practice. METHODS: The absorbed organ doses were measured by using an anthropomorphic phantom loaded with thermoluminescent dosimeters at 16 sites related to sensitive organs. The 4 devices (Sirona DS Plus [Sirona Dental Systems, Bernsheim, Germany], i-CAT [Imaging Sciences International, Hatfield, Pa], NewTom DVT 9000 [QR, Verona, Italy], and Somatom Sensation [Siemens Medical Solutions, Erlangen, Germany]) were used with standard protocols and, when possible, in the auto-exposure mode. Equivalent and effective doses were calculated. The calculation of the effective doses was based on the International Commission on Radiological Protection's 2005 recommendations. RESULTS: The lowest organ dose (13.1 microSv) was received by the thyroid gland during conventional panoramic and lateral cephalometric imaging. The highest mean organ dose (15,837.2 microSv) was received by the neck skin from the multi-slice CT. The effective dose was also lower for the panoramic and lateral cephalometric device (10.4 microSv), and highest for the multi-slice CT (429.7 microSv). CONCLUSIONS: From a radiation-protection point of view, conventional images still deliver the lowest doses to patients. When 3-dimensional imaging is required in orthodontic practice, a CBCT should be preferred over a CT image. Further studies are necessary to justify the routine use of CBCT in orthodontic treatment planning.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Má Oclusão/diagnóstico por imagem , Radiografia Dentária/métodos , Cefalometria , Tomografia Computadorizada de Feixe Cônico/instrumentação , Planejamento de Assistência ao Paciente , Imagens de Fantasmas , Doses de Radiação , Radiografia Panorâmica , Tomografia Computadorizada por Raios X
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