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1.
Osteoporos Int ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767743

RESUMO

This study investigates the effects of antiresorptive drugs and risk factors for medication-related osteonecrosis of the jaws in osteoporotic patients undergoing tooth extraction. Among the findings, antiresorptive-treated patients had thicker lamina dura and longer healing times. Additionally, corticosteroid intake and multi-rooted teeth carried a higher osteonecrosis risk. Bone sequestrum indicated osteonecrosis. PURPOSE: To describe the effects of antiresorptive drugs (ARD) in the maxilla and mandible and risk factors for medication-related osteonecrosis of the jaws (MRONJ) in osteoporotic patients undergoing tooth extractions using clinical data and cone beam computed tomography (CBCT). METHODS: This retrospective cohort study collected clinical and CBCT data from 176 patients. The study group (n = 78; 224 extractions) received ARD treatment, underwent tooth extraction, and had a pre-operative CBCT. Additionally, age-, sex-, and tooth-matched controls were selected (n = 98; 227 extractions). Radiographic examinations were performed independently by three calibrated examiners. Statistical analysis included Chi-square, Fisher's exact, Mann-Whitney U, and t-tests to contrast clinical and radiographic data between study and control, MRONJ + and MRONJ - , and bisphosphonate and denosumab patients/sites. Significance was set at p ≤ 0.05. RESULTS: From the study group, 4 patients (5%) and 5 sites (2%) developed MRONJ after tooth extraction. ARD-treated patients exhibited significantly more thickening of the lamina dura and a longer average mucosal healing time (4.4 weeks) than controls (2.6 weeks). In the study group, MRONJ risk significantly increased with corticosteroid intake and in multi-rooted teeth. No significant differences between bisphosphonates and denosumab use were seen in the tomographic features (p > 0.05). Lastly, bone sequestrum was exclusively observed in osteoporotic patients, who exhibited post-operative exposed bone or histological evidence of osteonecrosis. CONCLUSION: Osteoporotic patients under ARD may exhibit thickening of the lamina dura and prolonged post-operative healing. Among these patients, multi-rooted teeth are at higher risk for MRONJ than single-rooted teeth. Sequester formation is a radiographic indicator of osteonecrosis.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38553310

RESUMO

OBJECTIVE: This study aimed to assess the performance of a convolutional neural network (CNN) model in detecting the pubertal growth spurt by analyzing cervical vertebrae maturation (CVM) in lateral cephalometric radiographs (LCRs). STUDY DESIGN: In total, 600 LCRs of patients from 6 to 17 years old were selected. Three radiologists independently and blindly classified the maturation stages of the LCRs and defined the difficulty of each classification. Subsequently, the stage and level of difficulty were determined by consensus. LCRs were distributed between training, validation, and test datasets across 4 CNN-based models. The models' responses were compared with the radiologists' reference standard, and the architecture with the highest success rate was selected for evaluation. Models were developed using full and cropped LCRs with original and simplified maturation classifications. RESULTS: In the simplified classification, the Inception-v3 CNN yielded an accuracy of 74% and 75%, with recall and precision values of 61% and 62%, for full and cropped LCRs, respectively. It achieved 61% and 62% total success rates with full and cropped LCRs, respectively, reaching 72.7% for easy-to-classify cropped cases. CONCLUSION: Overall, the CNN model demonstrated potential for determining the maturation status regarding the pubertal growth spurt through images of the cervical vertebrae. It may be useful as an initial assessment tool or as an aid for optimizing the assessment and treatment decisions of the clinician.

3.
J Dent ; 141: 104829, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163456

RESUMO

OBJECTIVES: To assess the performance, time-efficiency, and consistency of a convolutional neural network (CNN) based automated approach for integrated segmentation of craniomaxillofacial structures compared with semi-automated method for creating a virtual patient using cone beam computed tomography (CBCT) scans. METHODS: Thirty CBCT scans were selected. Six craniomaxillofacial structures, encompassing the maxillofacial complex bones, maxillary sinus, dentition, mandible, mandibular canal, and pharyngeal airway space, were segmented on these scans using semi-automated and composite of previously validated CNN-based automated segmentation techniques for individual structures. A qualitative assessment of the automated segmentation revealed the need for minor refinements, which were manually corrected. These refined segmentations served as a reference for comparing semi-automated and automated integrated segmentations. RESULTS: The majority of minor adjustments with the automated approach involved under-segmentation of sinus mucosal thickening and regions with reduced bone thickness within the maxillofacial complex. The automated and the semi-automated approaches required an average time of 1.1 min and 48.4 min, respectively. The automated method demonstrated a greater degree of similarity (99.6 %) to the reference than the semi-automated approach (88.3 %). The standard deviation values for all metrics with the automated approach were low, indicating a high consistency. CONCLUSIONS: The CNN-driven integrated segmentation approach proved to be accurate, time-efficient, and consistent for creating a CBCT-derived virtual patient through simultaneous segmentation of craniomaxillofacial structures. CLINICAL RELEVANCE: The creation of a virtual orofacial patient using an automated approach could potentially transform personalized digital workflows. This advancement could be particularly beneficial for treatment planning in a variety of dental and maxillofacial specialties.


Assuntos
Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Tomografia Computadorizada de Feixe Cônico/métodos
4.
Braz Dent J ; 34(4): 150-157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909638

RESUMO

This study aimed to assess the influence of the file format on the image quality parameters (image noise, brightness, and uniformity) of periapical radiographs acquired with different digital systems. Radiographic images of an acrylic phantom were acquired with two digital systems - Digora Toto and Express, and exported into five different file formats - TIFF, BMP, DICOM, PNG, and JPEG. Image noise, image brightness (mean of gray values), and image uniformity (standard deviation of gray values) were evaluated in all images. A two-way analysis of variance with Tukey's test as a post-hoc test was used to compare the results, considering the file formats and radiographic systems as the studied factors. A significance level of 5% was adopted for all analyses. The DICOM image file format presented lower image noise, higher brightness (higher mean gray values), and greater image uniformity (p<0.001) than the other file formats, which did not differ from each other for both digital radiography systems (p>0.05). The Express system revealed lower image noise and greater image uniformity than the Digora Toto system regardless of the image file format (p<0.001). Moreover, the Express showed higher brightness than the Digora Toto for all image file formats (p<0.001), except for the DICOM image file format, which did not significantly differ between the digital radiography systems tested (p>0.05). The DICOM image file format showed lower image noise, higher brightness, and greater image uniformity than the other file formats (TIFF, BMP, PNG, and JPEG) in both digital radiography systems tested.


Assuntos
Radiografia Dentária Digital , Radiografia Dentária Digital/métodos
5.
Dentomaxillofac Radiol ; 52(8): 20230238, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37874081

RESUMO

OBJECTIVES: To identify clinical and local radiographic predictors for medication-related osteonecrosis of the jaws (MRONJ) by the assessment of pre-operative CBCT images of oncologic patients treated with anti-resorptive drugs (ARDs) undergoing tooth extractions. METHODS: This retrospective, longitudinal, case-control study included clinical and imaging data of 97 patients, divided into study and control group. Patients in the study group (n = 47; 87 tooth extractions) had received at least one dose of ARD, undergone tooth extraction(s), and had a pre-operative CBCT. An age-, gender-, and tooth extraction-matched control group (n = 50; 106 tooth extractions) was selected. Three calibrated, blinded, and independent examiners evaluated each tooth extraction site. Statistical analysis used χ2/Fisher's exact/Mann-Whitney U test to contrast control and study group, ARD type used, and sites with or without MRONJ development. p-value ≤ 0.05 was considered significant. RESULTS: From the study group, 15 patients (32%) and 33 sites (38%) developed MRONJ after tooth extraction. When controls were compared to study sites, the latter showed significantly more thickening of the lamina dura, widened periodontal ligament space, osteosclerosis, osteolysis, and sequestrum formation. In the study group, MRONJ risk significantly increased in patients who had multiple tooth extractions, were smokers, and had shorter drug holidays. Periosteal reaction and sequestrum formation may indicate latent MRONJ lesions. Additionally, patients given bisphosphonates showed considerably more osteosclerosis than those given denosumab. CONCLUSIONS: Periosteal reaction and sequestrum formation are suspected to be pre-clinical MRONJ lesions. Furthermore, ARD induced bony changes and radiographic variations between ARD types were seen.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Osteosclerose , Humanos , Conservadores da Densidade Óssea/efeitos adversos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Estudos Retrospectivos , Estudos de Casos e Controles , Difosfonatos/efeitos adversos , Extração Dentária/efeitos adversos
6.
Braz. dent. j ; 34(4): 150-157, July-Aug. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - odontologia (Brasil) | ID: biblio-1520332

RESUMO

Abstract This study aimed to assess the influence of the file format on the image quality parameters (image noise, brightness, and uniformity) of periapical radiographs acquired with different digital systems. Radiographic images of an acrylic phantom were acquired with two digital systems - Digora Toto and Express, and exported into five different file formats - TIFF, BMP, DICOM, PNG, and JPEG. Image noise, image brightness (mean of gray values), and image uniformity (standard deviation of gray values) were evaluated in all images. A two-way analysis of variance with Tukey's test as a post-hoc test was used to compare the results, considering the file formats and radiographic systems as the studied factors. A significance level of 5% was adopted for all analyses. The DICOM image file format presented lower image noise, higher brightness (higher mean gray values), and greater image uniformity (p<0.001) than the other file formats, which did not differ from each other for both digital radiography systems (p>0.05). The Express system revealed lower image noise and greater image uniformity than the Digora Toto system regardless of the image file format (p<0.001). Moreover, the Express showed higher brightness than the Digora Toto for all image file formats (p<0.001), except for the DICOM image file format, which did not significantly differ between the digital radiography systems tested (p>0.05). The DICOM image file format showed lower image noise, higher brightness, and greater image uniformity than the other file formats (TIFF, BMP, PNG, and JPEG) in both digital radiography systems tested.


Resumo Este estudo teve como objetivo avaliar a influência do formato do arquivo nos parâmetros de qualidade de imagem (ruído de imagem, brilho e uniformidade) de radiografias periapicais adquiridas com diferentes sistemas digitais. As imagens radiográficas de um fantoma de acrílico foram adquiridas com dois sistemas digitais - Digora Toto e Express, e exportadas em cinco formatos de arquivo diferentes - TIFF, BMP, DICOM, PNG e JPEG. O ruído da imagem, o brilho da imagem (média dos valores de cinza) e a uniformidade da imagem (desvio padrão dos valores de cinza) foram avaliados em todas as imagens. A análise de variância (ANOVA) bidirecional com o teste post-hoc de Tukey foi aplicada para comparar os resultados, considerando os formatos de arquivo e os sistemas radiográficos como os fatores estudados. Um nível de significância de 5% foi adotado para todas as análises. O formato de arquivo de imagem DICOM apresentou menor ruído de imagem, maior brilho (maiores valores médios de cinza) e maior uniformidade de imagem (p<0,001) do que os outros formatos de arquivo, que não diferiram entre si para ambos os sistemas de radiografia digital (p>0,05). O sistema Express apresentou menor ruído de imagem e maior uniformidade de imagem que o sistema Digora Toto, independentemente do formato do arquivo de imagem (p<0,001). Além disso, o Express mostrou maior brilho do que o Digora Toto para todos os formatos de arquivo de imagem (p<0,001), exceto para o formato de arquivo de imagem DICOM, que não diferiu significativamente entre os sistemas de radiografia digital testados (p>0,05). O formato de arquivo de imagem DICOM mostrou menor ruído de imagem, maior brilho e maior uniformidade de imagem do que os outros formatos de arquivo (TIFF, BMP, PNG e JPEG) em ambos os sistemas de radiografia digital testados.

7.
Clin Oral Investig ; 27(3): 1133-1141, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36114907

RESUMO

OBJECTIVE: To qualitatively and quantitatively assess integrated segmentation of three convolutional neural network (CNN) models for the creation of a maxillary virtual patient (MVP) from cone-beam computed tomography (CBCT) images. MATERIALS AND METHODS: A dataset of 40 CBCT scans acquired with different scanning parameters was selected. Three previously validated individual CNN models were integrated to achieve a combined segmentation of maxillary complex, maxillary sinuses, and upper dentition. Two experts performed a qualitative assessment, scoring-integrated segmentations from 0 to 10 based on the number of required refinements. Furthermore, experts executed refinements, allowing performance comparison between integrated automated segmentation (AS) and refined segmentation (RS) models. Inter-observer consistency of the refinements and the time needed to create a full-resolution automatic segmentation were calculated. RESULTS: From the dataset, 85% scored 7-10, and 15% were within 3-6. The average time required for automated segmentation was 1.7 min. Performance metrics indicated an excellent overlap between automatic and refined segmentation with a dice similarity coefficient (DSC) of 99.3%. High inter-observer consistency of refinements was observed, with a 95% Hausdorff distance (HD) of 0.045 mm. CONCLUSION: The integrated CNN models proved to be fast, accurate, and consistent along with a strong interobserver consistency in creating the MVP. CLINICAL RELEVANCE: The automated segmentation of these structures simultaneously could act as a valuable tool in clinical orthodontics, implant rehabilitation, and any oral or maxillofacial surgical procedures, where visualization of MVP and its relationship with surrounding structures is a necessity for reaching an accurate diagnosis and patient-specific treatment planning.


Assuntos
Implantes Dentários , Dente , Humanos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Redes Neurais de Computação
8.
Odovtos (En línea) ; 24(3)dic. 2022.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1406166

RESUMO

Abstract The aim of this study was to assess the use of digital dental radiology in Brazil, by focusing on the use of image receptors, imaging exams and digital image enhancement tools, also assessing the methods of professional image transfer. Questionnaires were distributed in person on dental meetings and digitally via messaging (WhatsApp®) and mailings list. The sample of this cross-sectional study consisted of 478 questionnaires. Most participants were woman (n=315, 65.9%), with average age of 33.8±9.2 years. Descriptive and frequency analysis was performed. Chi-square and Fisher's exact tests were used (α=0.05). Most dentists worked at shared dental clinics (34.7%) and use digital image receptors (51.1%), but a representative percentage (48.9%) still exclusively use radiographic films. Photostimulable phosphor plate is the most used digital image receptor. Among extraoral exams, panoramic radiography (PAN) is the most used. Regarding dental specialties, oral radiologists and oral and maxillofacial surgeons mostly use cone-beam computed tomography (p<0.001). Most dentists who use digital systems make use of digital image enhancement tools (87.8%), mainly contrast, zoom, brightness and measurements. The most common method of professional image transfer (professional-professional and professional-patiens) is by email, with few dentists using online app and social media (26%). Therefore, while most Brazilian dentists use digital imaging systems, a significant percentage still exclusively use radiographic films. The most extraoral imaging exams used is PAN. Regarding image enhancement tools, brightness and contrast adjustments, zoom and measurements are the most applied. Finally, dentists generally use email for professional image transfer.


Resumen El objetivo de este estudio fue evaluar uso de la radiología dental digital en Brasil, centrándose en uso de receptores de imagen, exámenes de imágenes y herramientas de mejora de imagen digital, evaluando también los métodos de transferencia de imagen profesional. Cuestionarios se distribuyeron de forma presencial en reuniones odontológicas y de forma digital a través de mensajería (WhatsApp®) y lista de correo. Muestra de este estudio transversal estuvo compuesta por 478 cuestionarios. Mayoría de los participantes eran mujeres (n=315, 65,9%), con edad promedio de 33,8±9,2 años. Se realizó un análisis descriptivo y de frecuencias. Se utilizaron las pruebas Chi-cuadrado y exacta de Fisher (α=0,05). La mayoría de los odontólogos trabajaban en clínicas dentales compartidas (34,7%) y utilizan receptores de imágenes digitales (51,1%), pero un porcentaje representativo (48,9%) todavía utiliza exclusivamente películas radiográficas. Placa de fósforo fotoestimulable es el receptor de imagen digital más utilizado. Entre los exámenes extraorales, la radiografía panorámica (PAN) es la más utilizada. En cuanto a las especialidades odontológicas, los radiólogos orales y los cirujanos orales y maxilofaciales utilizan mayoritariamente la tomografía computarizada de haz cónico (p<0,001). Mayoría de los odontólogos que utilizan sistemas digitales utilizan herramientas de mejora de imagen digital (87,8%), principalmente contraste, zoom, brillo y medidas. Método más común de transferencia de imágenes profesionales (profesional-profesional y profesional-pacientes) es por correo electrónico, con pocos dentistas que utilizan aplicaciones en línea y redes sociales (26%). Por lo tanto, mientras que la mayoría de dentistas brasileños utilizan sistemas de imágenes digitales, un porcentaje significativo aún utiliza exclusivamente películas radiográficas. Examen de imagen extraoral más utilizado es el PAN. En cuanto a las herramientas de mejora de imagen, los ajustes de brillo y contraste, el zoom y las medidas son las más aplicadas. Finalmente, los dentistas generalmente usan el correo electrónico para la transferencia de imágenes profesionales.


Assuntos
Intensificação de Imagem Radiográfica/tendências , Sistemas de Informação em Radiologia , Brasil , Diagnóstico por Imagem
9.
J Dent ; 124: 104238, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35872223

RESUMO

OBJECTIVES: The present study investigated the accuracy, consistency, and time-efficiency of a novel deep convolutional neural network (CNN) based model for the automated maxillofacial bone segmentation from cone beam computed tomography (CBCT) images. METHOD: A dataset of 144 scans was acquired from two CBCT devices and randomly divided into three subsets: training set (n = 110), validation set (n = 10) and testing set (n = 24). A three-dimensional (3D) U-Net (CNN) model was developed, and the achieved automated segmentation was compared with a manual approach. RESULTS: The average time required for automated segmentation was 39.1 s with a 204-fold decrease in time consumption compared to manual segmentation (132.7 min). The model was highly accurate for identification of the bony structures of the anatomical region of interest with a dice similarity coefficient (DSC) of 92.6%. Additionally, the fully deterministic nature of the CNN model was able to provide 100% consistency without any variability. The inter-observer consistency for expert-based minor correction of the automated segmentation observed an excellent DSC of 99.7%. CONCLUSION: The proposed CNN model provided a time-efficient, accurate, and consistent CBCT-based automated segmentation of the maxillofacial complex. CLINICAL SIGNIFICANCE: Automated segmentation of the maxillofacial complex could act as an alternative to the conventional segmentation techniques for improving the efficiency of the digital workflows. This approach could deliver accurate and ready-to-print3D models, essential to patient-specific digital treatment planning for orthodontics, maxillofacial surgery, and implant dentistry.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Tomografia Computadorizada de Feixe Cônico , Humanos , Processamento de Imagem Assistida por Computador/métodos
10.
Oral Radiol ; 38(4): 452-458, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34626307

RESUMO

OBJECTIVE: To evaluate the influence of the file format of digital periapical radiographs on the diagnosis of vertical root fracture (VRF). STUDY DESIGN: Periapical radiographic images of 34 single-rooted teeth-19 with VRF, and 15 without VRF were acquired using two digital systems-Digora Toto, and Digora Optime, and exported into four different file formats-TIFF, BMP, PNG, and JPEG, totaling 272 radiographs. The radiographs were assessed by five examiners for the detection of VRF, using a 5-point scale (1-definitely absent; 2-probably absent; 3-uncertain; 4-probably present; 5-definitely present). Diagnostic values of area under the ROC curve, specificity, and sensitivity for the diagnosis of VRF were calculated. The results were compared by two-way Analysis of Variance with post hoc Tukey's test. The intra- and inter-examiner agreements were measured by the Kappa test. The significance level was set at 5% for all analyses. RESULTS: The values of intra-examiner agreement varied from moderate (0.56) to almost perfect (0.81), while the values of inter-examiner agreement varied from fair (0.29) to moderate (0.60). The image file format did not influence the diagnostic values for VRF for any of the radiographic systems tested (p > 0.05). Digora Toto had significantly greater values of area under the ROC curve than Digora Optime for all file formats (p = 0.001). CONCLUSION: The image file format of periapical radiographs does not influence the diagnosis of VRF, regardless of the digital radiography system.


Assuntos
Fraturas dos Dentes , Humanos , Compostos de Quinolínio , Radiografia , Radiografia Dentária Digital/métodos , Tiazóis , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
11.
Clin Oral Investig ; 26(2): 1199-1215, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34800204

RESUMO

OBJECTIVE: To determine the prevalence of the elongated styloid process (ESP) and its characteristics, such as sex and age of the patient, unilateral and bilateral incidence, besides variations between different populations and panoramic and CBCT examinations. MATERIALS AND METHODS: A search was performed in six databases (PubMed, Web of Science, Scopus, Cochrane, Lilacs, and Embase) to identify observational studies that used imaging exams and assessed ESP prevalence among panoramic radiograph CBCT examinations, whose transversal prevalence studies were included. Furthermore, studies with a specific group of patients or symptomatic patients were excluded. Additionally, Joanna Briggs Institute checklist was used to evaluate the quality of the studies. A meta-analysis was conducted, then subgroup analyses were performed by grouping studies according to the secondary outcomes, with a significance level set at 5%. The Grading of Recommendations Assessment, Development, and Evaluation system was used to rate the certainty in the evidence. RESULTS: The initial search resulted in 1635 studies, from which 39 articles met the inclusion criteria, encompassing 50,655 participants. The sample size varied between 82 and 5,000 participants. The prevalence of the ESP ranged from 1.3 to 94.8%, with an overall prevalence of 30.2%. The bilateral occurrence was higher than the unilateral one, but no significant predilection was observed according to sex, age, or population. The type of imaging examination also showed no difference in its detection. CONCLUSION: The overall prevalence of ESP was 30.2%, with a propensity for bilaterality, but not for any sex, age, or population geographic location. The imaging examination modality did not influence the diagnosis of ESP. However, the quality level of the studies evaluated was very low, demonstrating the need for more homogeneous primary studies on the prevalence of the ESP with a more standardized methodology. CLINICAL RELEVANCE: There is no consensus in the literature regarding the prevalence of the ESP and the characteristics of the affected patients that can cause chronic and debilitating discomfort in the head and neck region. Therefore, knowledge about the prevalence and characteristics of this condition would help dental clinicians reach the correct diagnosis.


Assuntos
Ossificação Heterotópica , Humanos , Prevalência , Radiografia Panorâmica , Osso Temporal/anormalidades , Osso Temporal/diagnóstico por imagem
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