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1.
Medicine (Baltimore) ; 99(43): e22778, 2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33120788

RESUMEN

BACKGROUND: To analyze the sagittal positions of the mandibular prominence and maxillary central incisors in adult Chinese Han men to establish their aesthetic profile characteristics. METHODS: Seventy-four Chinese Han men aged 18 to 40 years underwent cone beam computed tomography for detecting the distances between Glabella and Subnasale, Subnasale and Menthon of soft tissue, Condyle and Gonion, Pogonion and Pogonion's Anterior Limit Line, Facial Axis point of maxillary central incisor and the Goal Anterior Limit Line as well as the angle of the Occlusal Plane. Dolphin Imaging and Photoshop software packages were used to generate silhouette profiles. Thirteen orthodontists assessed the silhouette profiles and assigned visual analog scale scores. Scores >70 were assigned to the aesthetic (group 1), scores of 60to 70 to the general (group 2), scores of 50 to 60 to the acceptable (group 3), and scores of <50 to the unaesthetic profile (group 4). RESULTS: A total of 15 men were assigned to group 1, 35 to group 2, 14 to group 3, and 10 to group 4. There were no significant differences in the variables examined between groups 1, 2, and 3, but comparing group 1 with group 4, Pogonion and Pogonion's Anterior Limit Line (1.16 ±â€Š2.61 mm vs -1.44 ±â€Š2.92 mm, P = .046) and Facial Axis-Goal Anterior Limit Line (-0.61 ±â€Š2.54 mm vs 1.70 ±â€Š2.62 mm, P = .038) there were significant differences. CONCLUSION: Compared with the unaesthetic profile group, the sagittal positions of the maxillary central incisors were slightly posterior, and the chin was slightly anterior in adult Chinese Han men with an aesthetic profile.


Asunto(s)
Grupos Étnicos , Incisivo/anatomía & histología , Incisivo/diagnóstico por imagen , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Adolescente , Adulto , Cefalometría/métodos , Mentón/anatomía & histología , Mentón/diagnóstico por imagen , China , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Masculino , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen , Estudios Prospectivos , Valores de Referencia , Adulto Joven
2.
Niger J Clin Pract ; 23(10): 1477-1482, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33047709

RESUMEN

Background: To assess maxillary sinus findings using dental volumetric tomography before and after surgery in patients with dental implants in the maxillary posterior region with or without sinus floor elevation due to insufficient bone height. Materials and Methods: Cone-beam computerized tomography images taken for surgical planning before implantation and controlling after implantation were reviewed in 50 patients applied to the Department of Oral, Dental and Maxillofacial Surgery and Radiology of Dentistry Faculty at Ondokuz Mayis University. Maxillary sinus diseases (focal mucosal thickening, polyp, mucous retention cyst, sinusitis) were evaluated. The relationship between dental implant and sinus floor augmentation procedures and maxillary sinus findings was statistically evaluated using the Chi-square test and Wilcoxon rank test. Results: In this study, 26 female (52%) and 24 male (48%) patients were examined. The mean age of all patients was 53.82 years (± 8.63). Focal mucosal thickening was most frequently observed in the study. There was no statistically significant correlation between implant applications and sinus pathologies with both internal and external elevation procedures and implant applications (P > 0.05). Conclusions: Sinus floor augmentation and dental implant applications seemed not to increase the risk of maxillary sinüs pathologies. However, it is suggested to carry out similar studies with more samples.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Implantes Dentales , Maxilar/cirugía , Seno Maxilar/diagnóstico por imagen , Elevación del Piso del Seno Maxilar , Adulto , Femenino , Humanos , Masculino , Seno Maxilar/cirugía , Persona de Mediana Edad
3.
PLoS One ; 15(9): e0239759, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32970759

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the effects of miniscrew insertion angle and vertical facial type on the interradicular miniscrew-root distance available for molar distalization. MATERIALS AND METHODS: Cone-beam computed tomography images of 60 adults with skeletal Class I occlusion exhibiting hyperdivergent (n = 20), normodivergent (n = 20), and hypodivergent (n = 20) facial types were used. Placement of a 6-mm long, 1.5-mm diameter, tapered miniscrew was simulated at a site 4 mm apical to the cementoenamel junction, with insertion angles of 0°, 30°, 45°, and 60° relative to the transverse occlusal plane. The shortest linear distance between the miniscrew and anterior root at four interradicular sites was measured: maxillary second premolar and first molar (Mx 5-6), maxillary first and second molars (Mx 6-7), mandibular second premolar and first molar (Mn 5-6), and mandibular first and second molars (Mn 6-7). RESULTS: Miniscrew-root distance significantly increased as the insertion angle increased from 0° to 60°. In the mandible, the distances significantly differed among vertical facial types, increasing in the following order: hyperdivergent, normodivergent, and hypodivergent. The minimum mean distance was found in the Mx 6-7 (30°; 0.86±0.35 mm), and the maximum mean distance was found in the Mn 5-6 (60°; 2.64±0.56 mm). The rates of miniscrews located buccally outside the root distalization path were up to 70% and 55% when the miniscrews were placed at 60° insertion angles in the Mx 5-6 and Mn 5-6 regions, respectively. CONCLUSIONS: Miniscrew-root distance increased significantly with the increased insertion angle, and the amount of increase was affected by the miniscrew placement site and vertical facial type. To ensure adequate distalization of the posterior segment, the miniscrew should be inserted at an angle in the interradicular area between the second premolar and first molar.


Asunto(s)
Tornillos Óseos , Simulación por Computador , Tomografía Computarizada de Haz Cónico/métodos , Diente Molar/diagnóstico por imagen , Métodos de Anclaje en Ortodoncia/métodos , Técnicas de Movimiento Dental/métodos , Raíz del Diente/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Métodos de Anclaje en Ortodoncia/instrumentación , Técnicas de Movimiento Dental/instrumentación
4.
Medicine (Baltimore) ; 99(37): e22189, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32925793

RESUMEN

Herein, a Harris corner detection algorithm is proposed based on the concepts of iterated threshold segmentation and adaptive iterative threshold (AIT-Harris), and a stepwise local stitching algorithm is used to obtain wide-field ultrasound (US) images.Cone-beam computer tomography (CBCT) and US images from 9 cervical cancer patients and 1 prostate cancer patient were examined. In the experiment, corner features were extracted based on the AIT-Harris, Harris, and Morave algorithms. Accordingly, wide-field ultrasonic images were obtained based on the extracted features after local stitching, and the corner matching rates of all tested algorithms were compared. The accuracies of the drawn contours of organs at risk (OARs) were compared based on the stitched ultrasonic images and CBCT.The corner matching rate of the Morave algorithm was compared with those obtained by the Harris and AIT-Harris algorithms, and paired sample t tests were conducted (t = 6.142, t = 31.859, P < .05). The results showed that the differences were statistically significant. The average Dice similarity coefficient between the automatically delineated bladder region based on wide-field US images and the manually delineated bladder region based on ground truth CBCT images was 0.924, and the average Jaccard coefficient was 0.894.The proposed algorithm improved the accuracy of corner detection, and the stitched wide-field US image could modify the delineation range of OARs in the pelvic cavity.


Asunto(s)
Algoritmos , Tomografía Computarizada de Haz Cónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias del Cuello Uterino/diagnóstico por imagen , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Ultrasonografía/métodos
5.
Plast Reconstr Surg ; 146(4): 847-858, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32970007

RESUMEN

BACKGROUND: No consensus exists about the safest position for performing the osseous genioplasty, with 5 to 6 mm below the mental foramen being the most frequently recommended position. This study intends to generate a safe distance guide to minimize the risk of inferior alveolar nerve injury during osteotomy. METHODS: Pretreatment cone-beam computed tomography-derived three-dimensional models from adult patients with skeletal class I to III patterns and cleft lip/palate deformity who underwent orthodontic-surgical interventions (n = 317) were analyzed. A three-dimensional vertical distance between the inferior margin of the mental foramen and the lowest point of the inferior alveolar nerve canal was measured in each three-dimensional hemimandible (n = 634). Statistical analysis was performed to generate the safe distance guide in a stepwise fashion at 95, 99, and 99.99 percent confidence levels. RESULTS: Class III (4.35 ± 1.42 mm) and cleft lip/palate (4.42 ± 1.53 mm) groups presented significantly (p < 0.001) larger three-dimensional distances than class I (3.44 ± 1.54 mm) and class II (3.66 ± 1.51 mm) groups. By considering the 5- to 6-mm safe distance parameter, 6.4, 5.0, 10.6, 16, and 9.9 percent of hemimandibles were at risk of osteotomy-induced nerve injury in the class I, class II, class III, cleft lip/palate, and overall cohorts, respectively. Overall, the safe distance zone to perform the osteotomy was set at 7.06, 8.01, and 9.12 mm below the mental foramen, with risk probabilities of 2.5, 0.5, and 0.0005 percent, respectively. CONCLUSION: This study contributes to patient safety and surgeon practice by proving a safe distance guide for genioplasty.


Asunto(s)
Labio Leporino/cirugía , Fisura del Paladar/cirugía , Tomografía Computarizada de Haz Cónico , Mentoplastia/métodos , Imagenología Tridimensional , Complicaciones Intraoperatorias/prevención & control , Lesiones del Nervio Mandibular/prevención & control , Nervio Mandibular/diagnóstico por imagen , Cirugía Asistida por Computador , Adolescente , Adulto , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Estudios Retrospectivos , Adulto Joven
6.
Br J Radiol ; 93(1115): 20200412, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32822249

RESUMEN

OBJECTIVE: To evaluate the performance of low dose cone beam CT (CBCT) acquisition protocols for image-guided radiotherapy of prostate cancer. METHODS: CBCT images of patients undergoing prostate cancer radiotherapy were acquired with the settings currently used in our department and two low dose settings at 50% and 63% lower exposure. Four experienced radiation oncologists and two radiation therapy technologists graded the images on five image quality characteristics. The scores were analysed through Visual Grading Regression, using the acquisition settings and the patient size as covariates. RESULTS: The low dose acquisition settings have no impact on the image quality for patients with body profile length at hip level below 100 cm. CONCLUSIONS: A reduction of about 60% of the dose is feasible for patients with size below 100 cm. The visibility of low contrast features can be compromised if using the low dose acquisition settings for patients with hip size above 100 cm. ADVANCES IN KNOWLEDGE: Low dose CBCT acquisition protocols for the pelvis, based on subjective evaluation of patient images.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Aceleradores de Partículas , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Radioterapia Guiada por Imagen/métodos , Radioterapia de Intensidad Modulada/métodos , Estudios de Factibilidad , Humanos , Masculino , Pelvis/diagnóstico por imagen , Dosis de Radiación , Radioterapia Guiada por Imagen/instrumentación , Radioterapia de Intensidad Modulada/instrumentación , Análisis de Regresión
7.
Cancer Imaging ; 20(1): 60, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32811570

RESUMEN

BACKGROUND: To investigate the potential value of volumetric iodine quantification using preoperative dual-energy computed tomography (DECT) for predicting microvascular invasion (MVI) of hepatocellular carcinoma (HCC). METHODS: This retrospective study included patients with single HCC treated through surgical resection who underwent preoperative DECT. Quantitative DECT features, including normalized iodine concentration (NIC) to the aorta and mixed-energy CT attenuation value in the arterial phase, were three-dimensionally measured for peritumoral and intratumoral regions: (i) layer-by-layer analysis for peritumoral layers (outer layers 1 and 2; numbered in close order from the tumor boundary) and intratumoral layers (inner layers 1 and 2) with 2-mm layer thickness and (ii) volume of interest (VOI)-based analysis with different volume coverage (tumor itself; VOIO1, tumor plus outer layer 1; VOIO2, tumor plus outer layers 1 and 2; VOII1, tumor minus inner layer 1; VOII2, tumor minus inner layers 1 and 2). In addition, qualitative CT features, including peritumoral enhancement and tumor margin, were assessed. Qualitative and quantitative CT features were compared between HCC patients with and without MVI. Diagnostic performance of DECT parameters of layers and VOIs was assessed using receiver operating characteristic curve analysis. RESULTS: A total of 36 patients (24 men, mean age 59.9 ± 8.5 years) with MVI (n = 14) and without MVI (n = 22) were included. HCCs with MVI showed significantly higher NICs of outer layer 1, outer layer 2, VOIO1, and VOIO2 than those without MVI (P = 0.01, 0.04, 0.02, 0.02, respectively). Among the NICs of layers and VOIs, the highest area under the curve was obtained in outer layer 1 (0.747). Qualitative features, including peritumoral enhancement and tumor margin, and the mean CT attenuation of each layer and each VOI were not significantly different between HCCs with and without MVI (both P >  0.05). CONCLUSIONS: Volumetric iodine quantification of peritumoral and intratumoral regions in arterial phase using DECT may help predict the MVI of HCC.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Adulto , Anciano , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Tomografía Computarizada de Haz Cónico/normas , Femenino , Humanos , Yodo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Microvasos/patología , Persona de Mediana Edad , Invasividad Neoplásica , Periodo Preoperatorio , Imagen Radiográfica por Emisión de Doble Fotón/normas
8.
Leg Med (Tokyo) ; 47: 101743, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32659706

RESUMEN

The aim in this study was to evaluate the influence of skeletal class, facial type, and sex on soft tissue thickness (STT) of the craniofacial midline in a Brazilian subpopulation. Thus, 121 cone beam computed tomography (CBCT) scans (54 males and 67 females, age 21 to 40 yrs) composed the study sample. Patients were classified according to skeletal class (class I, II, and III) and facial type (brachycephalic, mesocephalic, and dolichocephalic), and STT was measured (mm) in 10 landmarks in the craniofacial midline for each CBCT scan. Multivariate analysis of covariance evaluated facial STT with regard to multiple independent variables (sex, age - covariate, facial type, and skeletal class). TEM and rTEM assessed the intra-examiner agreement. STT was significantly greater in males than in females for all regions measured (p < 0.05), except for the pogonion-pogonion' landmark (p>0.05). In general, class III individuals had significantly thicker soft tissue in the maxilla - subspinale-subnasale', prosthion-labrale superius', and incision-stomion' regions, while class II subjects had thicker soft tissue in the infradentale-labrale inferius' mandibular landmark (p < 0.05). Regarding facial type, dolichocephalic individuals showed significantly thicker soft tissue in the supramentale-supramentale' mandibular landmark, whereas brachycephalic subjects had thicker soft tissue in maxillary regions - prosthion-labrale superius' and incision-stomion' (p < 0.05). rTEM values were below 5% for most landmarks, and all TEM values were below 1 mm. Skeletal class and facial type influence STT, showing a soft tissue compensation, with deeper soft tissue in areas with lower skeletal development, and/or where bone is positioned more posteriorly.


Asunto(s)
Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Tejido Conectivo/anatomía & histología , Tejido Conectivo/diagnóstico por imagen , Cara/anatomía & histología , Cara/diagnóstico por imagen , Huesos Faciales/anatomía & histología , Huesos Faciales/diagnóstico por imagen , Antropología Forense/métodos , Odontología Forense/métodos , Adulto , Brasil , Femenino , Humanos , Masculino , Caracteres Sexuales , Adulto Joven
9.
BMC Oral Health ; 20(1): 191, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32641102

RESUMEN

BACKGROUND: Periodontal diseases are prevalent among adult populations. Its diagnosis depends mainly on clinical findings supported by radiographic examinations. In previous decades, cone beam computed tomography has been introduced to the dental field. The aim of this study was to address the diagnostic efficacy of cone-beam computed tomographic (CBCT) imaging in periodontics based on a systematic search and analysis of the literature using the hierarchical efficacy model. METHODS: A systematic search of electronic databases such as PubMed, Scopus, Web of Science, and Cochrane was conducted in February 2019 to identify studies addressing the efficacy of CBCT imaging in Periodontics. The identified studies were subjected to pre-identified inclusion criteria followed by an analysis using a hierarchical model of efficacy (model) designed for an appraisal of the literature on diagnostic imaging modality. Four examiners performed the eligibility and quality assessment of relevant studies and consensus was reached in cases where disagreement occurred. RESULTS: The search resulted in 64 studies. Of these, 34 publications were allocated to the relevant level of efficacy and quality assessments wherever applicable. The overall diagnostic accuracy of the included studies showed a low or moderate risk of bias and applicability concerns in the use of CBCT. In addition, CBCT is accurate in identifying periodontal defects when compared to other modalities. The studies on the level of patient outcomes agreed that CBCT is a reliable tool for the assessment of outcomes after the treatment of periodontal defects. CONCLUSION: CBCT was found to be beneficial and accurate in cases of infra-bony defects and furcation involvements.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Enfermedades Periodontales/diagnóstico por imagen , Adulto , Odontología Basada en la Evidencia/métodos , Humanos , Tomografía Computarizada de Haz Cónico Espiral , Tomografía Computarizada por Rayos X
10.
Acta Odontol Latinoam ; 33(1): 22-26, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32621595

RESUMEN

Cone Beam Computed Tomography (CBCT) has modified the perspective of dentistry images, providing manipulable threedimensional images with a 1:1 patient:image ratio. Treatments and diagnosis are modified or corroborated by CBCT; however, its accuracy in thin structures such as cortical bone has been subjected to critical review. The aim of this study is to correlate the measurement of vestibular alveolar bone height using direct measurements and measurements performed with cone-beam tomographic images with standard (SD) voxel resolution. Thirty incisor and premolar teeth of patients undergoing open curettage were measured with a high-precision caliper and with Cone Beam Computed Tomography (CBCT) at an SD resolution of 0.16 mm voxels in a 3D Orthophos XG Sirona scanner. Intra-observer evaluation was performed using the intraclass correlation coefficient (ICC). Direct measurements and CBCT measurements were correlated using Pearson correlation (PCC). The mean difference between indirect and direct measurements was 3.15 mm. Paired t test and Pearson Correlation coefficient determined that all measurements differed statistically from each other with p<0.05. With the CT scanner and protocol used in this study, CBCT images do not enable accurate evaluation of vestibular alveolar bone height.


Asunto(s)
Proceso Alveolar/diagnóstico por imagen , Diente Premolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/normas , Incisivo/diagnóstico por imagen , Proceso Alveolar/anatomía & histología , Diente Premolar/anatomía & histología , Tomografía Computarizada de Haz Cónico/métodos , Precisión de la Medición Dimensional , Humanos , Incisivo/anatomía & histología , Reproducibilidad de los Resultados
11.
Orv Hetil ; 161(30): 1260-1265, 2020 07.
Artículo en Húngaro | MEDLINE | ID: mdl-32653869

RESUMEN

Surgical guides and three-dimensional (3D) planning softwares used in everyday dental implantology open new possibilities in other fields of dentistry. While using the operation microscope in endodontic microsurgery provides more precise apicectomy, there is still no consent on the exact localisation and size of the bony window to be prepared for this surgery. Our aim is to describe a new, guided endodontic microsurgery method when osteotomy and apicectomy are planned in a 3D software and performed with a trephine bur. Based on data from Cone Beam Computed Tomography, planning of the surgical guide was performed with a 3D planning software (Smart Guide, dicomLAB, Hungary) in order to define the size of the bony window, the angulation and the depth of the trephine bur during the apicectomy. After preparing a mucoperiosteal flap, with the help of the dentally supported surgical guide, the trephine bur removes the cortical bone and the apex of the root simultaniously. Following the modern microsurgical protocol, after performing the ultrasonic retrograde preparation, mineral trioxide aggregate (ProRoot MTA; Dentsply Maillefer, Ballaigues, Switzerland) is placed as a retrograde filling to close the resected area. After the uneventful healing period, a complete bony regeneration can be seen on the 1-year follow up X-ray. The patient is symptom-free. This technique is considered to be faster and more precise than the non-guided endodontic microsurgery carried out without the utilization of a trephine bur. Orv Hetil. 2020; 161(30): 1260-1265.


Asunto(s)
Apicectomía/métodos , Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/cirugía , Endodoncia/métodos , Microcirugia/métodos , Osteotomía/métodos , Impresión Tridimensional , Materiales de Obturación del Conducto Radicular , Tratamiento del Conducto Radicular/métodos , Compuestos de Aluminio , Compuestos de Calcio , Cavidad Pulpar/diagnóstico por imagen , Combinación de Medicamentos , Humanos , Hungría , Óxidos , Radiografía Dental , Silicatos , Diente , Resultado del Tratamiento , Procedimientos Quirúrgicos Ultrasónicos
12.
Niger J Clin Pract ; 23(7): 1026-1029, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32620736

RESUMEN

When teeth have responded poorly to conventional endodontic treatment or when they cannot be treated adequately by nonsurgical means, surgical endodontics remains the treatment of choice. Healing of apical lesions occurs by repair, most of the time. "Repair is the healing of a wound by tissue that does not fully restore the architecture or function of the affected unit". Since this is not ideal, newer regenerative procedures that aim to restore lost tissue have been introduced. ß -Tricalcium phosphate is an alloplastic bone graft material that forms a scaffold for closing the bony defect. It is osteoconductive. Platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are platelet concentrates, rich in growth factors and they promote regeneration by osteoinduction. This article describes cases of bone augmentation with a combination of PRP + ß -TCP and PRF + ß -TCP for treatment of the chronic periapical lesion. The cases were followed for six months and one year and healing was evaluated quantitatively using cone beam computed tomography.


Asunto(s)
Fosfatos de Calcio/uso terapéutico , Tomografía Computarizada de Haz Cónico/métodos , Fibrina Rica en Plaquetas , Plasma Rico en Plaquetas , Adulto , Regeneración Ósea , Trasplante Óseo , Femenino , Humanos , Radiografía Dental , Ápice del Diente/diagnóstico por imagen , Ápice del Diente/cirugía , Cuello del Diente/patología , Resultado del Tratamiento , Cicatrización de Heridas
13.
Folia Med Cracov ; 60(1): 85-96, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32658215

RESUMEN

OBJECTIVES: To identify tooth diseases as potential causative factors in the development of maxillary sinus lesions, with the aid of clinical examination combined with Cone Beam Computed Tomography (CBCT), in the patients with persistent sinus-like ailments, unresponsive to routine treatment offered by otolaryngologists. MATERIALS AND METHODS: In 44 patients with suspected odontogenic maxillary sinusitis, a dental examination with tooth vitality test was carried out, in conjunction with CBCT. The study involved 29 women and 15 men (age range 19-69 years, mean age 43 (SD = 13.9) years). RESULTS: In 15 (34.1%) patients the odontogenic lesions were encountered in maxillary sinuses. A total of 33 causative teeth were identified, of which 13 (39%) were after root canal treatment (RCT). Only one of the teeth had a properly reconstructed crown, and only one tooth had the root canals properly filled-in. Most frequently, the lesions in the sinuses were attributed to the inflammation of periapical tissues; the first molar having been established as the most common causative tooth. CONCLUSIONS: A detailed dental examination, pursued in conjunction with CBCT analysis, allow to diagnose odontogenic maxillary lesions. The incidence of long-term ailments originating in the maxillary sinuses should prompt a detailed assessment of the teeth, especially those after RCT.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Enfermedades Mandibulares/diagnóstico , Enfermedades Mandibulares/etiología , Sinusitis Maxilar/diagnóstico , Sinusitis Maxilar/etiología , Enfermedades Dentales/complicaciones , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Rev. cuba. estomatol ; 57(2): e2928, abr.-jun. 2020. graf
Artículo en Portugués | LILACS, CUMED | ID: biblio-1126512

RESUMEN

RESUMO Introdução: Exostose é um crescimento ósseo benigno que comumente acomete a mandíbula e a maxila, porém raramente apresenta grandes dimensões. Objetivo: Descrever um caso de exostose palatina de apresentação rara e discutir os principais aspectos clínicos envolvidos. Relato de caso: Paciente, gênero masculino, 66 anos, melanoderma, com história de aumento de volume no palato duro com tempo de evolução indeterminado, sem queixas álgicas, porém relatava transtornos de mastigação e fonação. O conjunto da lesão obliterava toda a profundidade do palato e ocupava grande volume na cavidade oral. A Tomografia Computadorizada de Feixe Cônico demonstrava áreas bem corticalizadas na superfície da lesão e áreas centrais menos hiperdensas, compatíveis com osso medular maduro. Após exames e pareceres pós-operatórios o paciente foi submetido a tratamento cirúrgico sob anestesia geral para remoção da massa óssea e osteoplastia subjacente, a fim de dar contornos normais ao palato, e o material colhido foi enviado para a biópsia que estabeleceu o diagnóstico de exostose. O paciente evoluiu sem complicações. Conclusão: Embora a exostose seja um crescimento ósseo benigno, ela causou problemas funcionais ao paciente, necessitando assim de um tratamento cirúrgico. Após três meses da remoção, os distúrbios foram revertidos à normalidade, e a sua reabilitação protética está em andamento(AU)


RESUMEN Introducción: La exostosis es un crecimiento óseo benigno que generalmente afecta la mandíbula y el maxilar, pero rara vez es grande. Objetivo: Describir un caso de exostosis palatina rara y discutir los principales aspectos clínicos involucrados. Presentación del caso: Paciente masculino de 66 años, melanoderma, con antecedentes de aumento de volumen del paladar duro con una evolución de tiempo indefinido, trastornos de masticación y fonación El conjunto de lesiones borró toda la profundidad del paladar y ocupó un gran volumen en la cavidad bucal. La tomografía computarizada de haz cónico mostró áreas corticalizadas en la superficie de la lesión y áreas centrales menos hiperdensas, compatibles con la médula ósea madura. Después de los exámenes y consejos preoperatorios, el paciente se sometió a un tratamiento quirúrgico con anestesia general para eliminar la masa ósea con osteoplastia subyacente a fin de obtener contornos del paladar normales, y el material recolectado fue enviado para realizar biopsia que estableció el diagnóstico de exostosis. El paciente progresó sin complicaciones. Conclusiones: Aunque la exostosis es un crecimiento óseo benigno, causó problemas funcionales al paciente, por lo que requirió tratamiento quirúrgico. Tres meses después de la extracción, los trastornos han vuelto a la normalidad y su rehabilitación protésica está en proceso(AU)


ABSTRACT Introduction: Exostosis is a benign bone growth that commonly affects the jaw and maxilla, but is rarely large. Objective: Describe a case of rare palatal exostosis and discuss the main clinical aspects involved. Case presentation: A case is presented of a male 66-year-old dark-skin patient with a history of hard palate enlargement of an indefinite time of evolution, and chewing and phonation disorders. The lesions had obliterated the entire palatal depth and occupied a large section of the oral cavity. Cone beam computed tomography revealed corticalized areas on the surface of the lesion and less hyperdense central areas compatible with mature bone marrow. After preoperative examination and advice, the patient underwent surgical treatment under general anesthesia to remove the bone mass and underlying osteoplasty to obtain normal palatal contours. The material collected was sent for biopsy testing, which established the diagnosis of exostosis. The patient recovered without any complications. Conclusions: Although exostosis is a benign bone growth, in this case it caused functional problems to the patient, thus requiring surgical treatment. Three months after removal, the disorders have been reverted to normal and prosthetic rehabilitation is underway(AU)


Asunto(s)
Humanos , Masculino , Anciano , Exostosis/diagnóstico , Paladar Duro/cirugía , Tomografía Computarizada de Haz Cónico/métodos
15.
J Craniofac Surg ; 31(5): e509-e511, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32541271

RESUMEN

Lingual lateral canal is a rare variation in the trajectory of the mandibular canal, and is usually detected as an incidental finding on radiographic exams, especially on cone-beam computed tomography. Due to its radiographic characteristics, this anatomical variation might be confused with a mandible fracture. Therefore, the knowledge of its presence is essential not only to differentiate it from a fracture, but also for the success of surgical procedures performed in the mandible, making it easier to avoid clinical complications such as swelling, bruising, bleeding, and neurovascular disorders. This report shows the case of a lingual lateral canal mimicking a fracture on the mandibular body.


Asunto(s)
Diagnóstico Diferencial , Fracturas Mandibulares/diagnóstico por imagen , Lengua/diagnóstico por imagen , Anciano , Variación Anatómica , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Masculino
16.
Br J Radiol ; 93(1112): 20200169, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32543946

RESUMEN

OBJECTIVES: The aim of this study was to assess the consistency of therapy radiographers performing image registration using cone beam computed tomography (CBCT)-CT, magnetic resonance (MR)-CT, and MR-MR image guidance for cervix cancer radiotherapy and to assess that MR-based image guidance is not inferior to CBCT standard practice. METHODS: 10 patients receiving cervix radiation therapy underwent daily CBCT guidance and magnetic resonance (MR) imaging weekly during treatment. Offline registration of each MR image, and corresponding CBCT, to planning CT was performed by five radiographers. MR images were also registered to the earliest MR interobserver variation was assessed using modified Bland-Altman analysis with clinically acceptable 95% limits of agreement (LoA) defined as ±5.0 mm. RESULTS: 30 CBCT-CT, 30 MR-CT and 20 MR-MR registrations were performed by each observer. Registration variations between CBCT-CT and MR-CT were minor and both strategies resulted in 95% LoA over the clinical threshold in the anteroposterior direction (CBCT-CT ±5.8 mm, MR-CT ±5.4 mm). MR-MR registrations achieved a significantly improved 95% LoA in the anteroposterior direction (±4.3 mm). All strategies demonstrated similar results in lateral and longitudinal directions. CONCLUSION: The magnitude of interobserver variations between CBCT-CT and MR-CT were similar, confirming that MR-CT radiotherapy workflows are comparable to CBCT-CT image-guided radiotherapy. Our results suggest MR-MR radiotherapy workflows may be a superior registration strategy. ADVANCES IN KNOWLEDGE: This is the first publication quantifying interobserver registration of multimodality image registration strategies for cervix radical radiotherapy patients.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Imagen por Resonancia Magnética/métodos , Imagen Multimodal/métodos , Variaciones Dependientes del Observador , Radioterapia Guiada por Imagen/métodos , Neoplasias del Cuello Uterino/radioterapia , Adulto , Anciano , Cuello del Útero/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , Neoplasias del Cuello Uterino/diagnóstico por imagen
17.
Braz Oral Res ; 34: e056, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32578799

RESUMEN

This study presents an overview of the accuracy of cone beam computed tomography (CBCT) compared with micro-computed tomography (µCT) in the assessment of root canal morphology of extracted human permanent teeth. A database search in PubMed, PubMed Central, Embase, Scopus, Opengrey, Scielo and Virtual Health Library was conducted which compared root canal morphology of extracted human permanent teeth on the accuracy of CBCT with µCT. In accordance with PRISMA statement guidelines, data were extracted on study characteristics, target mediators, sampling and assay techniques and the parameters associated with obtaining the image and ability to identify the root canal morphology. Amongst 2734 records, ten fulfilled the inclusion criteria. Four studies compared the accuracy of CBCT and µCT in the assessment of root canal morphology using Vertucci's classification, with at least one CBCT group or subgroup of each study presented high agreement compared to the µCT. Six studies assessed more detailed root canal morphology, including two articles that found a lack of agreement between these imaging systems. Risk of bias was deemed low in three studies, moderate in four and high in three. CBCT can be as accurate as µCT in the assessment of several morphological features of extracted human permanent teeth; however there are some exceptions related to the more detailed morphological aspects. Voxel size likely influences the ability to detect these features, though the different aspects of exposure setting used in studies components may be confounding factors. CBCT may be considered for the assessment of root canal morphology ex-vivo.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/anatomía & histología , Cavidad Pulpar/diagnóstico por imagen , Microtomografía por Rayos X/métodos , Humanos , Valores de Referencia , Factores de Riesgo
18.
Niger J Clin Pract ; 23(6): 759-763, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32525108

RESUMEN

Objective: The aim of this study was to detect the prevalence of soft tissue calcifications in the head and neck using cone beam computed tomography (CBCT) and to determine their clinical importance. Subjects and Methods: Soft tissue calcifications in the head and neck region were retrospectively evaluated in 1557 CBCT images obtained between 2013 and 2015. The findings were categorized as follows: tonsillolith (calcified tonsil), carotid artery calcification (CAC), sialolith (salivary stone), calcified triticeous cartilage (CTC), calcified lymph node (CLN), rhinolith, antrolith, calcification of the superior cornu of the thyroid cartilage (CSCTC), calcified stylohyoid ligaments (CSL), myositis ossifican, osteoma cutis, and intracranial calcification. A Chi-square test was performed for categorical variables. In the 1557 CBCT images, 520 (33.4%) contained had at least one soft tissue calcification in the head and neck region. Results: Tonsilloliths (18.8%) were the most prevalent soft tissue calcification, followed by CTC (5.8%), CAC (4.3%), intracranial calcifications (3.9%), CSL (3.7%), CSCTC (2.1%), osteoma cutis (1%), sialoliths (0.7%), antroliths (0.5%), myositis ossificans (0.4%), rhinoliths, and CLN (0.2%). Conclusion: There was a high prevalence of soft tissue calcifications in the head and neck region on CBCT images. Tonsilloliths were the most common type of calcification. CBCT imaging may aid the diagnosis and assessment of these calcifications.


Asunto(s)
Calcinosis/diagnóstico por imagen , Calcinosis/epidemiología , Tomografía Computarizada de Haz Cónico/métodos , Cabeza/diagnóstico por imagen , Cuello/diagnóstico por imagen , Tonsila Palatina/diagnóstico por imagen , Adulto , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/epidemiología , Enfermedades de los Cartílagos/diagnóstico por imagen , Enfermedades de los Cartílagos/epidemiología , Femenino , Humanos , Linfadenopatía/diagnóstico por imagen , Linfadenopatía/epidemiología , Masculino , Persona de Mediana Edad , Enfermedades Faríngeas/diagnóstico por imagen , Enfermedades Faríngeas/epidemiología , Prevalencia , Estudios Retrospectivos
19.
PLoS One ; 15(6): e0234915, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32555640

RESUMEN

OBJECTIVES: The aim of this study is 1) to obtain the area and volumes of the maxillary sinuses in patients affected by clinically unilateral sinus pathology by comparing the results to the contralateral sinus and 2) to determine the importance of the volumetric measures when diagnosing the percentage of sinus obliteration. MATERIALS AND METHODS: A single-centre observational retrospective clinical study was conducted in 214 patients with clinically unilateral sinus pathologies. Linear (mm), area (mm2) and volume (mm3) measurements were taken from Cone Beam Computed Tomography (CBCT) images of the affected sinus as well as from the contralateral ones. Histopathological study was performed using haematoxylin/eosin and PAS or Groccot stains. The lesions were classified into non-specific sinusitis, polyps, inverted papilloma, fungal sinusitis, cysts, mucocele and other lesions. Chi-squared test, ANOVA for independent samples and Pearson test were used for the statistical analysis. RESULTS: A total of 100 sinuses were measured in 50 patients (28 men and 22 women, with an age of 43.6 years (SD = 18.3), 50 pathological and 50 healthy contralateral sinuses. The three-dimensional occupation volume of the affected sinuses was 97.1 mm3 (62.5%) vs. 40.6 mm3 (22.8%) in the healthy ones (p<0.0001). The medial-lateral width of the sinus in the frontal plane was significantly higher in the cysts group (32.4 mm, CI: 23-41.8 mm). CONCLUSION: In medical terms, the global percentage of occupation determined using the classic manual determination method does not differ from the three-dimensional percentage calculated using specific complex software.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/patología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
20.
Phys Med Biol ; 65(16): 165012, 2020 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-32428891

RESUMEN

Metal artifacts present a challenge to cone-beam CT (CBCT) image-guided surgery, obscuring visualization of metal instruments and adjacent anatomy-often in the very region of interest pertinent to the imaging/surgical tasks. We present a method to reduce the influence of metal artifacts by prospectively defining an image acquisition protocol-viz., the C-arm source-detector orbit-that mitigates metal-induced biases in the projection data. The metal artifact avoidance (MAA) method is compatible with simple mobile C-arms, does not require exact prior information on the patient or metal implants, and is consistent with 3D filtered backprojection (FBP), more advanced (e.g. polyenergetic) model-based image reconstruction (MBIR), and metal artifact reduction (MAR) post-processing methods. The MAA method consists of: (i) coarse localization of metal objects in the field-of-view (FOV) via two or more low-dose scout projection views and segmentation (e.g. a simple U-Net) in coarse backprojection; (ii) model-based prediction of metal-induced x-ray spectral shift for all source-detector vertices accessible by the imaging system (e.g. gantry rotation and tilt angles); and (iii) identification of a circular or non-circular orbit that reduces the variation in spectral shift. The method was developed, tested, and evaluated in a series of studies presenting increasing levels of complexity and realism, including digital simulations, phantom experiment, and cadaver experiment in the context of image-guided spine surgery (pedicle screw implants). The MAA method accurately predicted tilted circular and non-circular orbits that reduced the magnitude of metal artifacts in CBCT reconstructions. Realistic distributions of metal instrumentation were successfully localized (0.71 median Dice coefficient) from 2-6 low-dose scout views even in complex anatomical scenes. The MAA-predicted tilted circular orbits reduced root-mean-square error (RMSE) in 3D image reconstructions by 46%-70% and 'blooming' artifacts (apparent width of the screw shaft) by 20-45%. Non-circular orbits defined by MAA achieved a further ∼46% reduction in RMSE compared to the best (tilted) circular orbit. The MAA method presents a practical means to predict C-arm orbits that minimize spectral bias from metal instrumentation. Resulting orbits-either simple tilted circular orbits or more complex non-circular orbits that can be executed with a motorized multi-axis C-arm-exhibited substantial reduction of metal artifacts in raw CBCT reconstructions by virtue of higher fidelity projection data, which are in turn compatible with subsequent MAR post-processing and/or polyenergetic MBIR to further reduce artifacts.


Asunto(s)
Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Metales/química , Fantasmas de Imagen , Columna Vertebral/cirugía , Cirugía Asistida por Computador/métodos , Algoritmos , Artefactos , Humanos , Imagenología Tridimensional/métodos , Tornillos Pediculares , Columna Vertebral/diagnóstico por imagen
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