Influence of CBCT parameters on image quality and the diagnosis of vertical root fractures in teeth with metallic posts: an ex vivo study.

Objectives: The aim of this study was to evaluate the influence of peak kilovoltage (kVp) and a metal artifact reduction (MAR) tool on image quality and the diagnosis of vertical root fracture (VRF) in cone-beam computed tomography (CBCT). Materials and Methods: Twenty single-rooted human teeth filled with an intracanal metal post were divided into 2 groups: control (n = 10) and VRF (n = 10). Each tooth was placed into the socket of a dry mandible, and CBCT scans were acquired using a Picasso Trio varying the kVp (70, 80, 90, or 99), and the use of MAR (with or without). The examinations were assessed by 5 examiners for the diagnosis of VRF using a 5-point scale. A subjective evaluation of the expression of artifacts was done by comparing random axial images of the studied protocols. The results of the diagnoses were analyzed using 2-way analysis of variance and the Tukey post hoc test, the subjective evaluations were compared using the Friedman test, and intra-examiner reproducibility was evaluated using the weighted kappa test (α = 5%). Results: The kVp and MAR did not influence the diagnosis of VRF (p > 0.05). According to the subjective classification, the 99 kVp protocol with MAR demonstrated the least expression of artifacts, while the 70 kVp protocol without MAR led to the most artifacts. Conclusions: Protocols with higher kVp combined with MAR improved the image quality of CBCT examinations. However, those factors did not lead to an improvement in the diagnosis of VRF.

How is the use of digital dental radiology in a developing country? An overview of Brazil / ¿Cómo es el uso de la radiología dental digital en un país en vías de desarrollo? Una visión general de Brasil

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.

Interexaminer agreement between two dental specialties for the detection of bifid mandibular canal and accessory mental foramen in cone-beam computed tomography / Concordancia inter-examinador entre dos especialidades odontológicas para la detección del canal mandibular bífido y foramen mental accesorio en tomografía computarizada de haz cónico

Introduction: The aim of this study was to assess the agreement between oral and maxillofacial radiologists (OMFR) and oral and maxillofacial surgeons (OMFS) for the detection of bifid mandibular canal (BMC) and accessory mental foramen (AMF) using cone-beam computed tomography (CBCT). Material and Methods: This retrospective study involved 22 examiners (11 OMFR and 11 OMFS) who independently assessed 30 CBCT volumes from patients (n = 60 hemi-mandibles) under preoperative radiographic evaluation for implant placement. The examiners scored the presence of BMC and AMF in each hemimandible. The interexaminer agreements were assessed using Fleiss' kappa statistics. Results: For intra-examiner agreement, 40% of the sample was reevaluated. The interexaminer agreement between OMFR and OMFS was slight (0.12) for the detection of BMC and fair (0.24) for AMF. The agreement among OMFR for detection of BMC was fair (0.22), and it was slight among OMFS (0.15). The agreement among OMFR for detection of AMF was substantial (0.61), and among OMFS it was fair (0.22). Agreements between OMFR and OMFS were slight for BMC and fair for AMF, independently of the years of experience. Intraexaminer agreement ranged from 60% to 90% among OMFR and from 55% to 90% among OMFS. Conclusion: A slight and a fair agreement between OMFR and OMFS was found for the detection of BMC and AMF, respectively. In general, OMFR obtained higher agreement among themselves, mainly for detection of AMF.

Introducción: El objetivo de este estudio fue evaluar la con-cordancia entre los radiólogos orales y maxilofaciales (ROMF) y los cirujanos orales y maxilofaciales (COMF) para la detección del canal mandibular bífido (CMB) y el foramen mentoniano accesorio (FMA) mediante tomografía computarizada de haz cónico. CBCT). Material y Métodos: Este estudio retrospectivo involucró a 22 examinadores (11 ROMF y 11 COMF) que evaluaron de forma independiente 30 volúmenes CBCT de pacientes (n = 60 hemimandíbulas) bajo evaluación radiográfica preoperatoria para la colocación de implantes. Los examinadores puntu-aron la presencia de CMB y FMA en cada hemimandíbula. Los acuerdos entre examinadores se evaluaron utilizando las estadísticas kappa de Fleiss. Resultados: Por concordancia intraexaminador se reeva-luó el 40% de la muestra. El acuerdo entre examinadores entre ROMF y COMF fue ligero (0,12) para la detección de CMB y regular (0,24) para FMA. La concordancia entre ROMF para la detección de CMB fue regular (0,22) y leve entre COMF (0,15). El acuerdo entre ROMF para la detección de FMA fue sustancial (0,61), y entre COMF fue justo (0,22). Los acuerdos entre ROMF y COMF fueron leves para CMB y justos para FMA, independientemente de los años de experiencia. La concordancia entre examinadores varió del 60 % al 90 % entre ROMF y del 55 % al 90 % entre COMF. Conclusión: Se encontró un acuerdo leve y justo entre ROMF y COMF para la detección de CMB y FMA, respec-tivamente. En general, se obtuvo mayor acuerdo entre ROMF, principalmente para la detección de FMA.

What is the accuracy of the surgical guide in the planning of orthognathic surgeries? A systematic review

Background: To investigate the true accuracy of the surgical guide in the planning of orthognathic surgeries, which are performed worldwide. Material and Methods: A systematic search was conducted in the PubMed database, Web of science, Scopus and Embase, covering August 2020 to January 2021. Studies that included patients with dentofacial deformity including anteroposterior, vertical and asymmetry problems who were undergoing an orthognathic surgery procedure were included; QUADAS-2 was used to determine the risk of bias by analyzing the quality of the studies. A PRISMA (flowchart) was created to show the study selection, keywords, nomination processes, and inclusion and exclusion criteria. Results: Eleven studies were selected for qualitative and quantitative synthesis. All studies evaluated described high precision of the surgical guide, where the lowest error values were represented by the CAD/CAM technique. Conclusions: The planning and printing errors related to the guide were all less than 2 mm, and the absolute averages of the errors related to virtual planning in the analysis of the different plans were less than 1 mm. Finally, the measurement of the ANB angle obtained equivalent results between the virtual planning and the traditional.(AU)

Comparison of CBCT and panoramic radiography for the assessment of bone loss and root resorption on the second molar associated with third molar impaction: a systematic review.

OBJECTIVE: To investigate whether the use of cone beam CT (CBCT) changes the diagnosis of external root resorption (ERR) or marginal bone loss (MBL) involving a second molar adjacent to an impacted third molar. METHODS: A systematic search was applied in PubMed, EMBASE, Scopus, Web of Science, LILACS, Google Scholar, OpenGrey, and ProQuest. Studies assessing the detection of ERR or MBL in a second molar adjacent to an impacted third molar through CBCT and panoramic radiography (PAN) were included. Prevalence and agreement between PAN and CBCT on the detection of ERR and MBL were collected. The risk of bias was assessed using the MAStARI. RESULTS: A total of 593 papers were identified, and after a 2-phase selection, 5 studies were included in the narrative synthesis. Regarding ERR, its prevalence in PAN was reported from 5.31 to 19.5% and from 22.8 to 62.0% in CBCT. The percentage of agreement varied from 28.5 to 74.0%. The prevalence of MBL varied from 21.9 to 62.9% in PAN, while those values varied from 21.6 to 80% in CBCT images. The percentage of agreement between PAN and CBCT for the detection of MBL ranged from 66.0 to 85.0%. Four studies presented low risk of bias and one had moderate risk. CONCLUSIONS: More ERR and MBL are assessed in CBCT compared to PAN. There is a considerable agreement between PAN and CBCT assessment of ERR and MBL, however, mostly related to the absence of the pathology rather its presence.

Influence of different viewing conditions on the detection of fractured endodontic instruments using periapical radiographs at 3 projection angles.

OBJECTIVES: The objective of this study was to assess the influence of ambient lighting levels and horizontal viewing angle (HVA) on the radiographic detection of fractured endodontic instruments in root canals in extracted human mandibular molars. STUDY DESIGN: Thirty-two root canals were selected. Endodontic instrument fracture was induced in 24 canals, and all canals were endodontially treated. Periapical radiographs were obtained at orthoradial, mesioradial, and distoradial projection angles. Five oral radiologists examined the radiographs for detection of fractured endodontic instruments under 3 ambient lighting levels (high, 450 lux; medium, 28 lux; and low, 2.5 lux) and 3 HVAs (90°, 67.5°, and 45°). Area under the receiver operating characteristic curve (AUROC), accuracy, sensitivity, and specificity were calculated and compared by 2-way analysis of variance using Tukey post hoc tests (α = .05). RESULTS: AUROC data indicated that ambient lighting (P = .739) and HVA (P = .238) did not significantly influence the detection of fractured endodontic instruments. Overall mean diagnostic values were 0.745, 0.57, 0.46, and 0.90 for AUROC, accuracy, sensitivity, and specificity, respectively. CONCLUSIONS: The viewing conditions assessed in this study did not influence the radiographic detection of fractured endodontic instruments in root canals.

Is peripheral cortication of intraosseous lesions accurately displayed on panoramic radiography?

OBJECTIVE: The aim of this study was to calculate the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) for the detection of the presence and continuity of peripheral cortication (PC) around benign intraosseous lesions on panoramic radiography (PR), with cone beam computed tomography (CBCT) as the reference standard. STUDY DESIGN: The sample consisted of the mesial, distal, superior, and inferior borders of 40 bony lesions (n = 160) depicted on both PR and CBCT. Ten observers assessed the PRs. CBCT images were assessed by 2 radiologists. For each lesion, observers classified the 4 borders with regard to the presence of PC, and if present, its continuity. Sensitivity, specificity, PPV, and NPV were calculated for the presence and continuity of PC. Intra- and interobserver agreements were calculated. RESULTS: PR had sensitivity, specificity, PPV, and NPV for PC detection of 0.844, 0.435, 0.435, and 0.844, respectively. With regard to PC continuity, those values were 0.750, 0.810, 0.577, and 0.904. Observer agreement was slight to fair. CONCLUSIONS: The high sensitivity and low specificity for the presence of PC indicate a large false-positive rate. The high NPVs suggest greater validity for negative decisions. The findings corroborate the influence of the eggshell effect. Observer agreement rates indicate that interpretation of PC is substantially subjective.

Radiographic evaluation of the prevalence of Stafne bone defect / Evaluación radiográfica de prevalencia de defecto óseo de Stafne

Stafne bone defect (SBD) is a bone cavity in the lingual surface of the mandible normally filled by salivary gland tissue. In conventional radiographs, SBD typically resembles a radiolucent unilocular lesion with welldefined margins, localized under the inferior alveolar canal. The diagnosis of SBD is often incidental due to the asymptomatic nature. The aim of this study was to investigate the prevalence of SBDs in a Brazilian population and to describe the radiographic features of the cases reported. This retrospective study evaluated 17,180 digital panoramic radiographs of patients with an indication of radiography for dental treatment seen at three centers located in the three Brazilian states. In each center, two researchers evaluated the images for establishment of the consensual diagnosis of SBD. In the case of disagreement, a third researcher was consulted to reach a final consensus. To assess the prevalence of SBDs, sex and age of patients were considered, and SBDs were classified according to their form and location. Data were submitted to descriptive analysis. Among the 17.180 patients, only 15 (0.08 %) had SDB, including 3 women and 12 men. The age range of the patients with SDB was 30-69 years (mean: 49.2). Fourteen cases were located in the posterior region of the mandibular body and one case in the ascending ramus. Stafne bone defect is a rare developmental anomaly that more commonly affects middle-aged men. The condition has a typical radiographic appearance and panoramic radiography is a valuable tool for its diagnosis.

El defecto óseo de Stafne (DOS) es una cavidad ósea en la superficie lingual de la mandíbula, normalmente llena de tejido glandular salival. En las radiografías convencionales, el DOS generalmente se asemeja a una lesión unilocular radiotransparente con bordes bien definidos, ubicada debajo del canal alveolar inferior. El diagnóstico de DOS a menudo es accidental debido a su naturaleza asintomática. El objetivo de este estudio fue investigar la prevalencia de DOS en una población brasileña y describir las características radiográficas de los casos reportados. Este estudio retrospectivo evaluó 17.180 radiografías panorámicas digitales de pacientes con indicación radiográfica para tratamiento dental atendidos en tres centros ubicados en tres estados brasileños. En cada centro, dos investigadores evaluaron las imágenes para establecer un diagnóstico consensuado de DOS. En caso de desacuerdo, se consultó a un tercer investigador para llegar a un consenso final. Para evaluar la prevalencia de DOS, se consideraron el sexo y la edad de los pacientes, y se clasificaron según su forma y ubicación. Los datos fueron sometidos a análisis descriptivo. Entre los 17.180 pacientes, solo 15 (0,08 %) tenían DOS, incluidos 3 mujeres y 12 hombres. El rango de edad de los pacientes con DOS fue de 30 a 69 años (media: 49,2). Catorce casos se ubicaron en la región posterior del cuerpo mandibular y un caso en la rama ascendente. Los defectos óseos de Stafne son una anomalía rara del desarrollo que afecta más comúnmente a los hombres de mediana edad. La condición tiene una apariencia radiográfica típica y la radiografía panorámica es una herramienta valiosa para su diagnóstico.

Brightness and contrast adjustments influence the radiographic detection of soft tissue calcification.

OBJECTIVE: To assess the influence of subjective enhancement of brightness and contrast of digital panoramic radiographs on the detection of soft tissue calcifications. MATERIALS AND METHODS: In this observational study, 500 digital panoramic radiographs were evaluated by two examiners in consensus, who scored the images for the presence of calcifications for each right and left side of the image. After 30 days, all images were revaluated under subjective manipulation of digital brightness and contrast. Calcifications were classified based on the diagnostic hypothesis: sialolith, tonsillolith, calcified atheroma, phlebolith, rhinolith, maxillary sinus antrolith, synovial chondromatosis, lymph node calcification, stylohyoid ligament, triticeous cartilage, or/and upper horn of thyroid cartilage calcification. For intra-examiner agreement, 20% of the sample was reevaluated. The Kappa test and McNemar test were used (α = 0.05). RESULTS: In original images, calcifications were observed in 44.2% of the patients, and in enhanced images, this number was 70.8%. Many calcifications were detected only in enhanced images, mainly in the diagnostic hypotheses of calcified atheroma and stylohyoid ligament. Intra-examiner agreement was excellent for the detection of soft tissue calcifications (0.82) and for the classification (0.81). CONCLUSION: Subjective enhancement of brightness and contrast alters the detection of soft tissue calcifications in digital panoramic radiograph.

Effect of brightness and contrast variation for detectability of root resorption lesions in digital intraoral radiographs.

OBJECTIVES: To evaluate the performance of periapical radiography assessed under different radiographic brightness and contrast variations in the detection of simulated internal (IRR) and external (ERR) root resorption lesions. Additionally, observers' preferences related to image quality for these diagnostic tasks were evaluated. METHODS: Thirty single-root teeth were divided into two groups (n = 15): IRR, in which lesions were simulated using mechanical and biochemical processes; and ERR, in which cavities standardized with drills of different sizes were performed on the root surfaces. Digital radiographs were obtained and subsequently adjusted in 4 additional combinations, resulting in 5 brightness/contrast variations (V1-V5). Five radiologists evaluated the radiographs. The observers' preference on the image quality was also recorded. RESULTS: For both conditions, there were no differences in the accuracy and specificity between the five brightness/contrast variations (p > 0.05), but the sensitivity for ERR was significantly lower in V4 (+ 15% brightness/-15% contrast) in the large size (p < 0.05). The observers classified V2 (- 15% brightness/+15% contrast) as the "best" image quality for IRR and ERR evaluation. CONCLUSIONS: For IRR and ERR lesions, brightness and contrast variation does not affect the diagnostic performance of digital intraoral radiography within the tested range. The observers prefer images with a reasonable decrease in brightness and increase in contrast. CLINICAL RELEVANCE: Brightness and contrast enhancement tools are commonly applied in digital radiographic assessment. The use of these tools for detection of root resorptions can be applied according to the observer preference without influence on diagnostic accuracy.