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1.
Int Endod J ; 52(6): 866-873, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30585641

RESUMEN

AIM: To assess the influence of artefacts, the metal artefact reduction (MAR) tool and kilovoltage (kVp) on the diagnosis of simulated external root resorption (ERR) in teeth close and distant to zirconium implants in cone beam computed tomography (CBCT) images. METHODOLOGY: Cavities (0.62 mm in diameter and 0.19 mm deep) were created in the apical thirds of 12 roots on the buccal, lingual, distal or mesial surface; ten roots served as controls. The roots were randomly positioned in the first and second right and left premolar sockets of a dry human mandible, and a zirconium implant was placed in the socket of the first right molar. A ProMax 3D unit varying kVp (70, 80, or 90 kVp) and with the MAR tool activated or not was used to obtain CBCT scans. Five examiners evaluated all images to determine the area under the receiver operating characteristic (ROC) curve, sensitivity and specificity. RESULTS: The ROC values and sensitivity were not affected by MAR or artefacts regardless of the distance to the implant (P > 0.05), whilst increasing kVp from 70 to 90 led to a significant increase in these values (P = 0.0202 and 0.0199, respectively). Specificity was not affected by the factors studied (P > 0.05). CONCLUSIONS: Amongst the factors studied, only kVp influenced the diagnosis of simulated external root resorption in CBCT images. Increasing kVp from 70 to 90 improved the accuracy in diagnosing the simulated lesions.


Asunto(s)
Resorción Radicular , Artefactos , Tomografía Computarizada de Haz Cónico , Humanos , Mandíbula , Raíz del Diente , Circonio
2.
Int J Oral Maxillofac Surg ; 46(8): 1017-1023, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28438443

RESUMEN

The aim of this study was to evaluate the anatomical linear measurements of the descending palatine canal and the pterygomaxillary fissure for Le Fort I preoperative planning. Seventy-five patients, comprising 46 females (61.3%) and 29 males (39.7%), underwent multi-slice computed tomography examinations performed for preoperative orthognathic surgical planning. The images were categorized according to sex, craniofacial side, and skeletal and craniofacial patterns. The anterior length between the descending palatine canal and the lateral wall of the piriform rim showed a higher mean value for males compared to females (P=0.0121). The posterior distance also showed a difference between the sexes and the highest mean was observed in females (P=0.0295). Comparing the posterior width for the skeletal patterns, a statistical difference was observed between classes I and III (P=0.0371), and classes II and III (P=0.0094). Regarding the craniofacial patterns, the brachycephalic (P=0.0078) and mesocephalic (P=0.0015) groups showed a greater posterior width in females. In conclusion, the patient's sex and aspects of the skeletal pattern and craniofacial pattern have an influence on the pterygomaxillary area and descending palatine canal anatomy. A preoperative computed tomography analysis involving this evaluation could reduce the risk of surgical complications.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Osteotomía Le Fort , Adulto , Puntos Anatómicos de Referencia , Femenino , Humanos , Masculino , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Factores Sexuales , Programas Informáticos
3.
Int Endod J ; 49(4): 386-92, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25980480

RESUMEN

AIM: To evaluate whether the type of display device affects the detection of vertical root fractures (VRFs) on digital radiographs in unfilled canals and canals with fibreglass posts. METHODOLOGY: Forty single-rooted human teeth were decoronated, and the root canals were prepared. The teeth were divided into 2 groups: controls (20 teeth) and with VRF (20 teeth). The VRFs were induced using an universal testing machine. Periapical radiographs of all teeth, with canal unfilled or with a fibreglass post, were obtained using the parallel technique in 3 directions (ortho-, mesio- and distoradial) on storage phosphor plates (VistaScan®). All images were evaluated and re-evaluated after 30 days by 3 examiners on a 5-point scale using 4 different devices (notebook display with full high definition resolution, desktop display with a standard resolution, 8-inch Android(™) tablet with high definition resolution and a 9.7-inch iPad® tablet with Retina resolution). Areas under ROC curves, sensitivity, specificity and accuracy values were compared by anova. RESULTS: The weighted kappa values for intra- and interobserver reproducibility were 0.55-0.88 and 0.31-0.65, respectively. There was a significant difference (P < 0.05) in relation to the area under the ROC curve, specificity and sensitivity when unfilled canals were compared with canals with a fibreglass post; however, no difference was observed for the different devices studied. CONCLUSIONS: The type of display device did not affect the detection of VRFs. Thus, the detection of VRFs can be performed using different screen sizes and resolutions.


Asunto(s)
Presentación de Datos , Radiografía Dental Digital/instrumentación , Fracturas de los Dientes/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Diente Premolar/diagnóstico por imagen , Humanos , Técnicas In Vitro , Mandíbula/diagnóstico por imagen , Reproducibilidad de los Resultados , Preparación del Conducto Radicular/métodos , Sensibilidad y Especificidad
4.
Dentomaxillofac Radiol ; 44(6): 20140428, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25764360

RESUMEN

OBJECTIVES: To assess the influence of the artefact reduction algorithm (AR) available on the Picasso Trio 3D(®) imaging system (Vatech, Hwaseong, Republic of Korea) on image quality [greyscale values, contrast-to-noise ratio (CNR) and artefact formation] and diagnosis of vertical root fractures (VRFs) in the teeth with intracanal metal posts. METHODS: 30 uniradicular teeth had their crowns removed and their roots endodontically treated to receive intracanal metal posts. In 20 teeth, both complete (n = 10) and incomplete (n = 10) VRFs were created. Each tooth was scanned twice, with and without AR activation. The mean and variation of greyscale values, as well as CNR, were calculated for all images. Subsequently, an evaluator compared the amount of artefact (cupping, white streaks and dark bands) in all images. Five evaluators rated for VRF presence using a five-point scale. RESULTS: Mean greyscale values and CNR were significantly decreased in images acquired with the AR. The usage of the algorithm promoted an overall reduction of image artefacts. Regarding the diagnosis of complete and incomplete VRFs, the use of the AR had an overall negative impact on specificity and accuracy. CONCLUSIONS: While indeed reducing artefact formation, the use of the AR, instead of improving the impact on the diagnosis of VRFs in teeth with intracanal metal posts, had a negative impact on the diagnosis.


Asunto(s)
Algoritmos , Tomografía Computarizada de Haz Cónico/métodos , Técnica de Perno Muñón/instrumentación , Fracturas de los Dientes/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Diente no Vital/diagnóstico por imagen , Humanos , Técnicas In Vitro , Metales
5.
Int Endod J ; 45(3): 234-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22003884

RESUMEN

AIM: To evaluate the diagnosis of simulated external root resorption in cone beam computed tomography (CBCT) images acquired with different voxel sizes, then reconstructed with the same voxel size. METHODOLOGY: Buccal, mesial and distal root surfaces of twenty single-rooted premolar teeth were evaluated for the presence or absence of simulated resorption defects. Images were obtained using a Classic i-CAT CBCT unit with two different voxel sizes (0.25 and 0.30 mm). Then all images were reconstructed to 0.25 mm voxel size. The McNemar's test was applied to evaluate the agreement between the two protocols (different voxel sizes/reconstruction parameters) with the gold standard (defects created in the root). Accuracy, sensitivity, specificity, positive and negative predictive values were calculated for each voxel and defect sizes. RESULTS: Better sensitivity and accuracy were obtained with 0.25 (0.25 mm) voxel size. Specificity, positive and negative predictive values were highest with the 0.25 (0.30 mm) voxel size. McNemar's test results revealed significant differences between the protocols with the gold standard (P < 0.0001). The results revealed that as the cavity size increased, sensitivity, accuracy, positive and negative predictive values also increased. When correlating the voxel size and root third, better sensitivity, accuracy, positive and negative predictive values were obtained in the middle third. CONCLUSIONS: In the diagnosis of simulated external root resorption with the Classic i-CAT CBCT unit, images acquired with 0.30 mm voxel size and reconstructed with 0.25 mm voxel size provided the best protocol with a lower radiation dose than the 0.25 mm voxel size.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Resorción Radicular/diagnóstico por imagen , Diente Premolar/diagnóstico por imagen , Humanos , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Intensificación de Imagen Radiográfica/métodos , Resorción Radicular/clasificación , Sensibilidad y Especificidad , Ápice del Diente/diagnóstico por imagen , Cuello del Diente/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen
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