Influência do tipo de compósito e tempo de exposição aos raios-x na produção de artefatos radiográficos em modelo de restaurações classe II / Influence of the composite type and exposure time to x-rays on the production of radiographic artifacts in a class II restoration model

Aim: To evaluate the effect of the exposure time and the type of composite in the production of radiographic artifact at the tooth / restorative interface. Materials and Methods: In 20 healthy bovine incisors, cavity preparations and class II restorations were made using composite resins Filtek Bulk Fill One (group 1) and Filtek Z350 (group 2). Then, the teeth were exposed to obtain digital radiographs, varying the exposure time by 0.07, 0.10, 0.14, 0.20 and 0.25s. The images were evaluated for investigation of the presence of artifact through the analysis of the modified number of pixels (QPXD) and the average gray value in class II (MGVR) restorations, using the Image J software (National Health Institute). Results: The presence of artifact was observed in all evaluated samples, regardless of the type of restorative material and the exposure time employed. There was no statistically significant difference in QPXD and MGVR between the resins used (ANOVA 2 factors, p p> 0.05). The MGVR analysis indicated that there were no statistically significant differences between resins or between exposure times (p> 0.05). There was a correlation between QPXD and MGVR (r = 0.29) for Filtek Bulk Fill One resin. Discussion: This study reveals the importance of attention to the region of the tooth-restoration interface by the Surgeon-Dentist, who must combine the radiographic findings diagnosed using digital tools to clinical signs in order to compose a unique therapeutic project with a real need for intervention, if there is such need. Conclusion: The presence of altered pixels on dentin in the region of the tooth-restoration interface was identified in all specimens. The variation in the exposure time as well as the type of the restorative composite did not influence the increase or decrease of QPXD and neither in MGVR. However, there was a correlation between QPXD and MGVR for Filtek Bulk Fill One resin.

Objetivo: Avaliar o efeito do tempo de exposição e do tipo de compósito na produção de artefato radiográfico na interface dente/material restaurador. Materiais e Métodos: Em 20 incisivos bovinos hígidos foram feitos preparos cavitários e restaurações classe II utilizando resinas compostas Filtek Bulk Fill One (grupo 1) e a Filtek Z350 (grupo 2). Em seguida, os dentes foram expostos para obtenção das radiografias digitais, variando o tempo de exposição em 0,07, 0,10, 0,14, 0,20 e 0,25s. As imagens foram avaliadas para investigação da presença de artefato através da análise do número de pixels modificado (QPXD) e do valor médio de cinza nas restaurações de classe II (MGVR), utilizando o software Image J (Instituto Nacional de Saúde, Bethesda, MD, EUA). Resultados: Observou-se a presença de artefato em toda amostra avaliada, independente de tipo de material restaurador e tempo de exposição empregado. Não se observou diferença estatisticamente significativa na QPXD e nos MGVR entre as resinas utilizadas (ANOVA 2 fatores, p p>0,05). A análise do MGVR indicou que não houve diferenças estatisticamente significativas entre as resinas nem entre os tempos de exposição (p>0,05). Observou-se uma correlação entre a QPXD e o MGVR (r=0,29) para a resina Filtek Bulk Fill One. Discussão: Como significado clínico, o presente estudo revela a importância da atenção à região da interface dente-restauração por parte do Cirurgião-Dentista, o qual deve aliar os achados radiográficos diagnosticados com o auxílio de ferramentas digitais aos sinais clínicos, para compor um projeto terapêutico singular com uma real necessidade de intervenção, caso haja. Conclusão: Foi identificado a presença de pixels alterados sobre a dentina na região da interface dente-restauração em todos os corpos de prova. A variação do tempo de exposição como também o tipo do compósito restaurador não influenciou no aumento ou diminuição do QPXD e nem tão pouco no MGVR. Contudo houve correlação entre o QPXD e o MGVR para a resina Filtek Bulk Fill One.

Assessment of infection control in oral radiology during the COVID-19 outbreak: An international collaborative study.

Purpose: In the context of COVID-19, studies evaluating the adherence of dentists and dental students to infection control are relevant due to their high occupational exposure and risk, as well as their responsibility for disseminating information and good practices. This study evaluated the adherence of dentists and dental students to infection control in the oral radiology field in the setting of the COVID-19 pandemic on different continents. Materials and Methods: This cross-sectional observational study involved individuals who performed intraoral radiographic examinations during the COVID-19 pandemic. The Questionnaire on Infection Control in Oral Radiology was administered virtually using a Google Form. Participants from different continents (the Americas, Africa, Europe, Asia, and Oceania) were recruited. Data were subjected to descriptive analysis and simple and multiple binary regression (5%). Results: There were 582 valid answers, and 68.73% of the participants were from the Americas, 18.90% from Europe, and 12.37% from Asia. The median score for infection control protocols was 94 points for dental students and 104 points for dentists, and participants below the median were considered to have low adherence to infection control in oral radiology. Low access to infection control was found for 53.0% of dentists in the Americas, 34.0% from Europe, and 26.9% from Asia. Conclusion: The adherence to infection control protocols in oral radiology was low even in the face of the COVID-19 pandemic. The results may help improve the awareness of students and professionals, since oral radiology routines have the potential for transmitting COVID-19.

Clinical comparison of intraoral CMOS and PSP detectors in terms of time efficiency, patient comfort, and subjective image quality.

Purpose: This study compared the effectiveness of complementary metal-oxide semiconductors (CMOS) and photostimulable phosphor (PSP) plates as intraoral imaging systems in terms of time efficacy, patient comfort, and subjective image quality assessment in real clinical settings. Materials and Methods: Fifty-eight patients (25 women and 33 men) were included. Patients were referred for a full-mouth radiological examination including 1 bitewing radiograph (left and right) and 8 periapical radiographs for each side (left maxilla/mandible and right maxilla/mandible). For each patient, 1 side of the dental arch was radiographed using a CMOS detector, whereas the other side was radiographed using a PSP detector, ensuring an equal number of left and right arches imaged by each detector. Clinical application time, comfort/pain, and subjective image quality were assessed for each detector. Continuous variables were summarized as mean±standard deviation. Differences between detectors were evaluated using repeated-measures analysis of variance. P<0.05 was accepted as significant. Results: The mean total time required for all imaging procedures with the CMOS detector was significantly lower than the mean total time required for imaging procedures with PSP (P<0.05). The overall mean patient comfort scores for the CMOS and PSP detectors were 4.57 and 4.48, respectively, without a statistically significant difference (P>0.05). The performance of both observers in subjectively assessing structures was significantly higher when using CMOS images than when using PSP images for all regions (P<0.05). Conclusion: The CMOS detector was found to be superior to the PSP detector in terms of clinical time efficacy and subjective image quality.

Evaluation of the microstructure, chemical composition, and image quality of different PSP receptors

Abstract This study aimed to assess the microstructure, chemical composition, and image quality of different photostimulable phosphor plates (PSP). Four PSP systems, Express®, Digora®, VistaScan®, and Apixia,® were assessed. Five radiographs of a homogeneous acrylic phantom were obtained with the PSP of each system, to acquire a total of 20 images. The images were objectively evaluated for uniformity using mean grey and standard deviation (SD) of their grey values. PSP receptors were analyzed using scanning electron microscopy (SEM) to determine the thickness of the granule layer and the size of the granules. The chemical composition of the PSP receptors was analyzed using total reflection X-ray fluorescence (TXRF). VistaScan showed more uniform and higher density images than the other tested systems (p < 0.05), as well as the lowest SD of grey values (p < 0.05). Regarding the microstructure of the receptors, Digora and VistaScan had thicker granule layers than Express and Apixia, and VistaScan had smaller granules than Digora and Express (p < 0.05). Fourteen chemical elements were detected in the receptors, with barium being the element with the highest concentration in all PSP systems. The microstructure, chemical composition, and image quality varied among all four PSP receptors studied. VistaScan receptors showed the smallest variation in granule size, one of the thickest granule layers, and the most uniform and least noisy images.

Imaginologic resources used in diagnosis of root resorptions: comparative study / Recursos imaginológicos utilizados no diagnóstico de reabsorções radiculares: estudo comparativo

ABSTRACT Objective: Compare the accuracy of early diagnosis of simulated internal root resorptions and external root resorption, using digital periapical radiography and cone beam computed tomography. Methods: Root resorption were simulated in extracted human teeth by demineralization with 5% nitric acid solution and 8% Sodium Hypochlorite in different periods (1 and 5 days). For the group external root resorption (n=12) composite resin cylinders were positioned on middle third of buccal surface of roots, to delimit application of demineralization substances. In group internal root resorptions (n=12) the teeth were sectioned longitudinally, and the composite resin cylinders were positioned in the middle third of root canals. The teeth were mounted in a dry mandible and evaluated by digital radiography and tomography. The images were evaluated by two examiners. Results: Analyzing the tomographic images in period of 1 day, the examiner 2 identified internal root resorptions that were not identified in radiographic images (p<0.05). No examiner was capable of diagnosing external root resorption irrespective of exam, in the group of 1 day (p>0.05). In 5 day period of induction, both exams identified internal root resorptions (p>0.05), however, the tomographic images were more effective in identifying external root resorption (p <0.05) for both examiners. Conclusion: Cone beam computed tomography was shown to be more effective than digital periapical radiography for detecting internal root resorptions with 1 day of induction. The imaginological resources used in this study were not able to early detect external root resorption.

RESUMO Objetivo: Comparar a acurácia do diagnóstico precoce de reabsorções radiculares interna (RRI) e reabsorções radiculares externa (RRE) simuladas, por meio de radiografia periapical digital e tomografia computadorizada de feixe cônico. Métodos: Reabsorções radiculares foram simuladas em dentes humanos extraídos utilizando a desmineralização com ácido nítrico 5% e hipoclorito de sódio 8% em diferentes períodos (1 e 5 dias). Para o grupo reabsorções radiculares externa (n=12) cilindros de resina composta foram posicionados no terço médio das faces vestibulares das raízes, delimitando a aplicação das substâncias de desmineralização. No grupo reabsorções radiculares interna (n=12) os dentes foram seccionados longitudinalmente, e os cilindros de resina posicionados no terço médio dos canais radiculares. Os dentes foram montados em mandíbula seca e avaliados por meio de radiografia digital e tomografia por dois examinadores. Resultados: Nas imagens tomográficas no período de 1 dia, o examinador 2 identificou reabsorções radiculares interna as quais não foram identificadas nas radiografias (p<0,05). Nenhum examinador foi capaz de diagnosticar as reabsorções radiculares externa independente do exame no grupo de 1 dia (p>0.05). No período de indução de 5 dias ambos os exames identificaram as reabsorções radiculares interna (p>0,05), entretanto, as tomografias foram mais eficazes na identificação das reabsorções radiculares externa (p<0,05) para ambos os examinadores. Conclusão: A tomografia computadorizada de feixe cônico mostrou-se mais eficaz do que a radiografia periapical digital na detecção de reabsorções radiculares interna com 1 dia de indução. Os recursos imaginológicos utilizados neste estudo não foram capazes de detectar precocemente a reabsorção radicular externa.

Evaluation of the radiopacity of restorative materials with different structures and thicknesses using a digital radiography system.

PURPOSE: The aim of this study was to evaluate the radiopacities of various types of restorative materials with different thicknesses compared with enamel, dentin, and aluminum. MATERIALS AND METHODS: Four bulk-fill resins, 2 hybrid ceramics, 2 micro-hybrid resin composites, 6 glass ionomer-based materials, 2 zinc phosphate cements, and an amalgam were used in the study. Twelve disk-shaped specimens were prepared from each of 17 restorative materials with thicknesses of 1 mm, 2 mm, and 4 mm (n=4). All the restorative material specimens with the same thickness, an aluminum (Al) step wedge, and enamel and dentin specimens were positioned on a phosphor storage plate and exposed using a dental X-ray unit. The mean gray values were measured on digital images and converted to equivalent Al thicknesses. Statistical analyses were performed using 2-way analysis of variance and the Bonferroni post hoc test (P<0.05). RESULTS: Radiopacity was significantly affected by both the thickness and the material type (P<0.05). GCP Glass Fill had the lowest radiopacity value for samples of 1 mm thickness, while Vita Enamic had the lowest radiopacity value for 2-mm-thick and 4-mm-thick samples. The materials with the highest radiopacity values after the amalgam were zinc phosphate cements. CONCLUSION: Significant differences were observed in the radiopacities of restorative materials with different thicknesses. Radiopacity was affected by both the material type and thickness.

Diagnóstico de reabsorção radicular: influência da resolução espacial de captura de imagens digitais periapicais / Root resorption diagnostic: influence of periapical digital image scanning

Introdução: a detecção da reabsorção da raiz dentária é realizada por meio de exames de imagens, pois frequentemente não apresenta sinal e sintoma clínicos. Dentre os exames de imagem disponíveis, o exame radiográfico periapical, é indicado para diagnóstico, prognóstico e acompanhamento da reabsorção radicular. Objetivo: o estudo tem como objetivo investigar a relação de diferentes resoluções espaciais com o diagnóstico de reabsorção radicular. Metodologia: foram realizados desgastes simulando reabsorção externa no terço apical e vestibular de 15 (quinze) incisivos inferiores, radiografados em crânio seco, antes e depois do desgaste. A técnica radiográfica foi realizada utilizando o sistema VistaScan (Durr Dental, Bietigheim-Bissingen, Germany), aparelho CS 2200 (Carestream Dental LLC, Atlanta-GA, USA) usando tempo de exposição de 0,15 segundos e escaneadas sob diferentes protocolos de resolução espacial, a saber, 20 pares de linhas por milímetro (pl/mm) e 40 pl/mm. Posteriormente dois avaliadores experientes fizeram análises das referidas imagens sem conhecimento prévio da resolução de escaneamento. Resultados: 75% das radiografias realizadas com 20 pl/mm foram classificadas como excelentes pelos avaliadores, contra 33% com 40 pl/mm, estatisticamente significativa. Discussão: ao avaliar a reabsorção radicular, obteve-se uma acurácia diagnóstica igual para os dois protocolos sem distinção, estatisticamente significativa, entre localização ou profundidade. Conclusão: tendo em vista que para os examinadores imagens com 20 pl/mm foram satisfatórias, com percentual de qualidade maior quando comparado a imagens obtidas com 40 pl/ mm, este estudo indica o emprego de imagens com 20 pl/mm para avaliação inicial de suspeita de reabsorções nas raízes dentárias.

Introduction: the detection of tooth root resorption is carried out by means of imaging tests, as it often does not present a clinical sign and symptom. Among the imaging tests available, the periapical radiographic examination is indicated for diagnosis, prognosis and monitoring of root resorption. Objective: the study aims to investigate the relationship of different spatial resolutions in the diagnosis of root resorption. Methods: Artificial external root resorptions were simulated using burs by drilling to the entire depth in different locations at the apical and buccal thirds of 15 (fifteen) lower incisors were worn, radiographed on a dry skull, before and after wear. The radiographic technique was performed using the VistaScan system (Durr Dental, Bietigheim-Bissingen, Germany), CS 2200 device (Carestream Dental LLC, Atlanta-GA, USA) using an exposure time of 0.15 seconds and scanned under different resolutions protocols, namely, 20 pairs of lines per millimeters (pl/mm) and 40 pl/mm. Subsequently, two experienced evaluators performed analyzes of these images without prior knowledge of the scanning resolution. Results: seventy-five percent of the radiographs taken at 20 pl/mm were rated as excellent by the evaluators, against 33% at 40 pl/mm, a statistically significant difference. Discussion: When assessing root resorption, a similar diagnostic accuracy was obtained for the two protocols without a statistically significant distinction between location or depth. Conclusions: Considering that for examiners images with 20 pl/mm were satisfactory, with a percentage of quality greater than 40 pl/mm, this study indicates the use of 20 pl/mm for initial evaluation of suspected root resorption.

Barriers and Enablers for Artificial Intelligence in Dental Diagnostics: A Qualitative Study.

The present study aimed to identify barriers and enablers for the implementation of artificial intelligence (AI) in dental, specifically radiographic, diagnostics. Semi-structured phone interviews with dentists and patients were conducted between the end of May and the end of June 2020 (convenience/snowball sampling). A questionnaire developed along the Theoretical Domains Framework (TDF) and the Capabilities, Opportunities and Motivations influencing Behaviors model (COM-B) was used to guide interviews. Mayring's content analysis was employed to point out barriers and enablers. We identified 36 barriers, conflicting themes or enablers, covering nine of the fourteen domains of the TDF and all three determinants of behavior (COM). Both stakeholders emphasized chances and hopes for AI. A range of enablers for implementing AI in dental diagnostics were identified (e.g., the chance for higher diagnostic accuracy, a reduced workload, more comprehensive reporting and better patient-provider communication). Barriers related to reliance on AI and responsibility for medical decisions, as well as the explainability of AI and the related option to de-bug AI applications, emerged. Decision-makers and industry may want to consider these aspects to foster implementation of AI in dentistry.

Fractal analysis of the trabecular bone pattern in the presence/absence of metal artifact-producing objects: Comparison of cone-beam computed tomography with panoramic and periapical radiography.

OBJECTIVES: The effect of metallic objects on the fractal dimension (FD), bone area fraction (BAF) and gray scale values (GSVs) of cone-beam CT (CBCT) images was assessed. Also, FD, BAF and GSV were compared among CBCT, digital periapical and panoramic radiographies. METHODS: Digital periapical and panoramic radiographs were acquired from six blocks of bovine rib. Additionally, different arrangements of titanium implants and intracanal metallic posts were created in the bone blocks and CBCT scans were taken from the different implant-root arrangements. The three radiographical modalities were compared by analysis of variance. Pairwise comparisons between the modalities were performed by the Tukey test (significance level set at 0.05). RESULTS: Different root-implant arrangements in the CBCT images revealed no significant differences in the FD (p = 0.920), BAF and GSV values (p = 0.623). FD differed significantly among the three modalities (p < 0.001). Significant differences were found between CBCT and each of the periapical and panoramic techniques (p < 0.001), while no remarkable differences were observed in the FD of the periapical and panoramic images (p = 0.294). BAF and GSV showed significantly different results among the three radiographical techniques (p < 0.001). The difference was remarkable between CBCT and periapical (p < 0.001), CBCT and panoramic (p < 0.001) and periapical and panoramic (p = 0.008). CONCLUSION: Presence of titanium implants and intracanal posts does not produce different results in the fractal analysis (FA) of the CBCT images. The trabecular bone pattern is best assessed by FA of the periapical radiographs followed by the panoramic and CBCT techniques, respectively.

Accuracy of digital bitewing radiographs with and without applying horizontal tube shift in the diagnosis of residual excess cement around dental implants: an in vitro study / Precisión de las radiografías digitales bitewing con y sin aplicación de desplazamiento horizontal del tubo en el diagnóstico del exceso de cemento residual alrededor de los implantes dentales: un estudio in vitro

Purpose: This study was designed to evaluate the diagnostic value of digital Bitewing (BW) radiographs with and without horizontal tube shift in detecting Residual excess cement (REC) on the proximal and non-proximal surfaces of implant restorations. Material and Methods: Eight mandibular models were fabricated with two implants placed on each side in the premolar and first molar positions. Excess cement was applied to either proximal or non-proximal surfaces of the restorations intentionally during the process of crown cementation. BW radiographs with and without applying horizontal tube shift were acquired. Three maxillofacial radiologists were asked to determine the presence and location of REC in the radiographs. Sensitivity and specificity of the radiographic technique were assessed according to the restoration surface that contained REC. Results: Sensitivity of BW radiographs was 100% for the detection of REC on the proximal surfaces and 41-18, 80% on the non-proximal surfaces. Specificity of the technique was 85.71%-100% for the proximal surfaces and 75-94. 12% for the non-proximal areas. Specificity of the radiographic method was generally greater than its sensitivity for the non-proximal surfaces while in the proximal areas, the two variables had quite similar values. Conclusion: Digital BW radiography is generally more useful for detection of REC on the proximal surfaces. Higher specificity of this technique for the bucco-lingual surfaces suggests more reliability of the negative diagnoses in the non-proximal areas.

Objetivo: Evaluar el valor diagnóstico de las radiografías digitales bitewing (BW), con y sin desplazamiento horizontal del tubo, para detectar el exceso de cemento residual (ECR) en las superficies proximales y no proximales de las restauraciones con implantes. Material y Métodos: Se fabricaron ocho modelos mandibulares con dos implantes colocados a cada lado en las posiciones premolar y primer molar. El exceso de cemento se aplicó intencionalmente en las superficies proximales o no proximales de las restauraciones durante el proceso de cementación de la corona. Se adquirieron radiografías BW con y sin aplicación de desplazamiento horizontal del tubo. Se pidió a tres radiólogos maxilofaciales que determinaran la presencia y ubicación de ECR en las radiografías. La sensibilidad y la especificidad de la técnica radiográfica se evaluaron según la superficie de restauración que contenía ECR. Resultados: La sensibilidad de las radiografías de BW fue del 100% para la detección de ECR en las superficies proximales y del 41,18-80% en las superficies no proximales. La especificidad de la técnica fue 85-71, 100% para las superficies proximales y 75-94, 12% para las áreas no proximales. La especificidad del método radiográfico fue generalmente mayor que su sensibilidad para las superficies no proximales, mientras que en las áreas proximales, las dos variables tuvieron valores bastante similares. Conclusión: La radiografía digital BW es generalmente más útil para la detección de ECR en las superficies proximales. La mayor especificidad de esta técnica para las superficies buco-linguales sugiere una mayor confiabilidad de los diagnósticos negativos en las áreas no proximales.

Comparison of Abundance of Premolar and Molar Pulp Stones before and after Orthodontic Treatment Using Panoramic Radiography.

Objectives: Pulp stone is a focal calcification in dental pulp, which is often detected on conventional dental radiographs. Pulp stones can complicate easy access to the root canal and pulp chamber in root canal treatment. Orthodontic treatment may be associated with the formation of pulp stones. Therefore, this study examined the number of pulp stones pre- and post-orthodontic treatment. Materials and Methods: In this retrospective cross-sectional comparative study, 222 digital panoramic radiographs collected from private orthodontic offices in Rasht, were divided into two groups: radiographs of patients undergoing orthodontic and non-orthodontic treatment according to the inclusion criteria. The obtained data were analyzed by SPSS via the Wilcoxon and Mann-Whitney tests (P<0.05). Results: The difference in the number of pulp stones pre- and post-orthodontic treatment was significant (P<0.0001). The maximum number of pulp stones after orthodontic treatment was observed in second molars (P=0.016). The change in the number of pulp stones in the mandible (P=0.001) was significantly higher than that in the maxilla (P=0.002). This change was also greater in the left side (P<0.0001) than in the right side (P=0.002). The changes in the number of pulp stones was significant in females (P=0.02). Age had an insignificant effect on pulp stone formation (P>0.05). Conclusion: This study showed the effect of orthodontic treatment on the number of pulp stones. Further studies are required to clarify the underlying mechanisms for this increase and come up with strategies to prevent it.

Comparison of the diagnostic accuracy of cone beam computed tomography and three intraoral radiographic systems in the diagnosis of carious lesions in vitro / Comparación de la precisión diagnóstica de la tomografía computarizada de haz cónico y tres sistemas radiográficos intraorales en la detección de lesiones de caries in vitro

Objective: The objective of the study was to compare the diagnostic accuracy of cone beam computed tomography and three intraoral radiographic systems in the detection of in vitro caries lesions. Material and Methods: One hundred teeth (46 molars and 54 premolars) were evaluated, including 176 proximal surfaces and 90 occlusal surfaces, with or without dental caries lesions. Digital images of all teeth were obtained using specific intraoral radiographs, VistaScan DürrDental®phosphor-plate radiography, XIOS XG Sirona® digital sensor radiography, and CBCT I-CATTM. Observers evaluated the images for the detection of caries lesions. The teeth were clinically sectioned and stereomicroscopy served as a validation tool. The relationship of sensitivity and specificity between all systems was determined through the ROC curve using Az values. Results: The values of the area under the curve (Az) selected for the CBCT I-CATTM system were 0.89 (0.84-0.93), for conventional radiography 0.71 (0.66-0.76), digital sensor radiography 0.74 (0.70-0.78) and digital radiography with phosphor-plates 0.73 (0.69-0.77). Statistically significant differences were found between the CBCT I-CATTM system and intraoral radiographic systems (p<0.01). The sensitivity and specificity values for the CBCT I-CATTM were 0.84 and 0.93 respectively. Conclusion: CBCT has a high sensitivity and specificity compared to intraoral radiographic systems for the diagnosis of dental caries lesions in vitro.

Objetivo: El objetivo del estudio fue comparar la precisión diagnóstica de la tomografía computarizada de haz cónico y tres sistemas radiográficos intraorales en la detección de lesiones de caries in vitro. Material y Métodos: Se evaluaron 100 dientes, 46 molares y 54 premolares; 176 superficies proximales y 90 superficies oclusales, con o sin lesión de caries dental. Se obtuvieron imágenes digitales de todos los dientes utilizando radiografías intraorales convencionales, radiografía con placas de fósforo VistaScan DürrDental®, radiografía con sensor digital XIOS XG Sirona® y CBCT I- C ATTM. Tres observadores evaluaron las imágenes para la detección de lesiones de caries. Los dientes se seccionaron clínicamente y la estereomicroscopía sirvió como herramienta de validación. Se determinó relación de sensibilidad y especificidad entre todos los sistemas a través de la curva ROC utilizando valores Az. Resultados: Los valores de área debajo de la curva (Az) obtenidos para el sistema CBCT I-CATTM fueron de 0.89 (0.84-0.93), para radiografía convencional 0.71 (0.66-0.76), radiografía con sensor digital 0.74 (0.70-0.78) y radiografía digital con placas de fósforo 0.73 (0.69-0.77). Se encontró diferencias estadísticamente significativas entre el sistema CBCT I-CATTM y todos los sistemas radiográficos convencionales y digitales (p<0.01). Los valores de sensibilidad y especificidad para el CBCT I-CATTM fueron 0.84 y 0.93 respectivamente. Conclusión: La CBCT tiene una alta sensibilidad y especificidad en comparación a los sistemas radiográficos intraorales en el diagnóstico de lesiones de caries dental in vitro.

Detection of different foreign bodies in the maxillofacial region with spiral computed tomography and cone-beam computed tomography: An in vitro study.

PURPOSE: The detection and exact localization of penetrating foreign bodies are crucial for the appropriate management of patients with dentoalveolar trauma. This study compared the efficacy of cone-beam computed tomography (CBCT) and spiral computed tomography (CT) scans for the detection of different foreign bodies composed of 5 frequently encountered materials in 2 sizes. The effect of the location of the foreign bodies on their visibility was also analyzed. MATERIALS AND METHODS: In this in vitro study, metal, tooth, stone, glass, and plastic particles measuring 1×1×1 mm and 2×2×2 mm were prepared. They were implanted in a sheep's head in the tongue muscle, nasal cavity, and at the interface of the mandibular cortex and soft tissue. CBCT and spiral CT scans were taken and the visibility of foreign bodies was scored by 4 skilled maxillofacial radiologists who were blinded to the location and number of foreign bodies. RESULTS: CT and CBCT were equally accurate in visualizing metal, stone, and tooth particles of both sizes. However, CBCT was better for detecting glass particles in the periosteum. Although both imaging modalities visualized plastic particles poorly, CT was slightly better for detecting plastic particles, especially the smaller ones. CONCLUSION: Considering the lower patient radiation dose and cost, CBCT can be used with almost equal accuracy as CT for detecting foreign bodies of different compositions and sizes in multiple maxillofacial regions. However, CT performed better for detecting plastic particles.

Radiopacity of endodontic materials using two models for conversion to millimeters of aluminum

Abstract The aims of the present study were to compare conventional radiography, radiographs digitized with a scanner or photographic camera, and digital radiography, used to evaluate the radiopacity of endodontic materials, and to compare the accuracy of linear and quadratic models used to convert radiopacity values to equivalent millimeters of aluminum (mm Al). Specimens of AH Plus, Endofill, Biodentine and BioMTA materials (n = 8) were radiographed next to an aluminum step-wedge using radiographic films and digital radiography systems (FONA CMOS sensor, Kodak CMOS sensor and photosensitive phosphor plate-PSP). Conventional radiographs were digitized using a scanner or photographic digital camera. Digital images of all the radiographic systems were evaluated using dedicated software. Optical density units (ODU) of the specimens and the aluminum step-wedge were evaluated by a photo-densitometer (PTDM), used in conventional radiographs. The radiopacity in equivalent mm Al of the materials was determined by linear and quadratic models, and the coefficients of determination (R2) values were calculated for each model. Radiopacity of the materials ranged from -9% to 25% for digital systems and digitized radiographs, compared to the PTDM (p < 0.05). The R2 values of the quadratic model were higher than those of the linear model. In conclusion, the FONA CMOS sensor showed the lowest radiopacity variability of the methodologies used, compared with the PTDM, except for the BioMTA group (higher than PTDM). The quadratic model showed higher R2 values than the linear model, thus indicating better accuracy and possible adoption to evaluate the radiopacity of endodontic materials.

Automatic exposure compensation and subjective image enhancement in the radiographic diagnosis of caries

Abstract This study aims to assess the influence of high-density material on the radiographic diagnosis of proximal caries in digital systems with automatic exposure compensation, and to evaluate the effect of subjective adjustment of brightness and contrast to undertake this diagnostic task. Twenty bitewing radiographs of forty posterior human teeth with non-cavitated carious lesions, confirmed by micro-CT, were obtained with two digital systems. A porcelain-fused-to-metal crown attached to a titanium implant was inserted into the exposed area, and all the radiographs were repeated. Five radiologists assessed the radiographs and diagnosed proximal carious lesions. Afterwards, the observers were asked to adjust image brightness and contrast, based on their subjective perception, and to reassess the images. Thirty percent of each experimental group was reassessed to test intraobserver reproducibility, totaling 208 images per observer. Intraobserver and interobserver agreements ranged from fair to substantial. Sensitivity, specificity, predictive values, and area under the ROC curve were calculated and compared for each radiographic system, using ANOVA (α = 0.05). Overall, presence of high-density material and adjustment of brightness and contrast did not significantly influence the radiographic diagnosis of proximal caries (p ≥ 0.05). Regarding Digora Optime, adjustment of brightness and contrast significantly increased (p < 0.05) the diagnostic accuracy of proximal carious lesions in the presence of high-density material. In conclusion, the presence of high-density material in the X-rayed region does not influence radiographic diagnosis of proximal caries. However, when it is present in the X-rayed area, subjective adjustment of brightness and contrast is recommended for use with the Digora Optime digital system.

Effectiveness of Two Types of Photostimulable Phosphor Plate Plastic Barrier Envelopes for Prevention of Microbiological Contamination

Abstract Objective: To compare the effectiveness of two types of commercially available photostimulable phosphor plate (PSP) protective barrier envelopes to prevent microbiological contamination. Material and Methods: In this cross-sectional study, 80 barrier envelopes were tested in 40 volunteers. The PSP plates were placed individually in Asia Teb and Soredex protective barrier envelopes and were placed in the mouth for two minutes, similar to periapical films. The protective barrier envelopes were then removed under sterile conditions, and the sensors were placed on different culture media. The number of colonies on each plate was counted. Data were analyzed using SPSS via McNemar and Wilcoxon tests. Results: Bacterial growth was noted in 17.5% of PSPs with Soredex, and 32.5% of PSPs with Asia Teb barrier envelopes. Gram-positive bacilli were the most commonly isolated bacteria. The difference between the Asia Teb and Soredex barrier envelopes for the protection of microbiological contamination was not significant (p>0.05). Conclusion: The use of different types of protective barrier envelopes was not sufficient for prevention of microbiological contamination of PSP plates, and some adjunct modalities were required to decrease microbiological contamination of PSP plates.

Use of Mini-Implant Anchorage For Second Molar Mesialization: Comprehensive Approach For Treatment Efficiency Analysis

Abstract Objective: To approbate the complex approach for assessment of second molar mesialization outcomes with the use of orthodontic mini-implants. Material and Methods: The sample consisted of 62 patients, divided into study (n=32) and control group (n=30). Mesialization procedure in the study group was conducted with the use of braces system and orthodontic mini-implants as additional anchorage devices, while in control group mesialization was provided only with the use of the brace system. Dynamic registration of bone level changes and the entire range of tooth movement were carried out on digital orthopantomograms obtained with the use of Planmeca ProMax 2D. Results: Findings of orthopantomographic (OPG) analysis have shown that cases of second molar mesialization with the use of mini-implants as temporary anchorage characterized with more stable conditions of bone levels around displaced teeth compare to cases, where mesialization was provided only with the use of braces systems without any additional anchorage. The terms of treatment in the study group with the use of dental mini-implants as the anchorage was reduced by 8.8 ± 0.12 months compared to the control group (p<0.05). Conclusion: The use of orthodontic mini-implants as anchorage constructions during the mesialization of the mandibular second molars contributes to the reduction of treatment duration and support the more prognostic movement of teeth, that does not provoke significant pathological changes in the levels of the surrounded alveolar ridge and minimize the risk of associated periodontal complication occurrence.

Influência do torque de inserção, tipo ósseo receptor e perda óssea peri-implantar na estabilidade primária e secundária de implantes cilíndricos hexágono externo e cone morse / Influence of insertion torque, receptor bone type and peri-implant bone loss on the primary and secondary stability of cylindrical external hexagon and morse cone implants

A osseointegração está relacionada à estabilidade do parafuso e influencia a taxa de sucesso de uma reabilitação com próteses implanto-suportadas, pois promove cicatrização natural e formação óssea efetiva, facilitando a preservação do implante no leito receptor. Fatores como a técnica cirúrgica, o torque de inserção, o tipo de osso receptor, e a macro e microestrutura do implante podem influenciar a estabilidade do parafuso. O objetivo deste estudo foi analisar in vivo a influência do torque de inserção, tipo ósseo receptor e perda óssea peri-implantar nos valores do coeficiente de estabilidade do implante (ISQ) de implantes cilíndricos hexágono externo (HE) e cone morse (CM). Foram instalados 43 implantes em áreas edêntulas de 20 pacientes selecionados seguindo critérios de inclusão e exclusão predefinidos. Imediatamente após a instalação dos implantes (t1) foi mensurado o torque de inserção, e foi realizado a análise de frequência de ressonância, a análise radiográfica e a análise peri-implantar. Estas análises foram realizadas novamente após a osseointegração (t2), e os dados obtidos foram analisados estatisticamente, com testes específicos para cada tipo de análise e nível de significância de 5%. Os resultados demonstraram que os valores de ISQ quando mensuradas por meio da análise de frequência de ressonância (AFR) foram similares para implantes cilíndricos HE e CM. A estabilidade destes implantes foi influenciada pelo torque de inserção (torques mais baixos proporcionaram aumento da estabilidade secundária) e tipo ósseo receptor (implantes HE instalados em osso do tipo II e IV e os implantes CM instalados em ossos do tipo II e III apresentaram aumento da estabilidade secundária). Já a perda óssea periimplantar, desde que dentro dos padrões de normalidade, não influenciou na estabilidade primária e secundária destes implantes. Assim, os resultados obtidos neste estudo recomendam que explorar e desenvolver a AFR como método de avaliação da estabilidade implantar deve ser uma busca ainda necessária das pesquisas científicas para melhor compreensão do comportamento dos implantes dentários, nos seus diversos momentos e situações na cavidade oral, bem como determinar um bom nível de estabilidade que consequentemente determinaria uma maior longevidade e funcionalidade dos implantes dentários(AU)

Osseointegration is related to the stability of the screw and influences the success rate of a rehabilitation with implant-supported prostheses, as it promotes natural healing and effective bone formation, facilitating the preservation of the implant in the recipient bed. Factors such as the surgical technique, the insertion torque, the type of recipient bone, and the macro and microstructure of the implant can influence the stability of the screw. The aim of this study was to analyze in vivo the influence of insertion torque, receptor bone type and peri-implant bone loss on the values of the implant stability coefficient (ISQ) of cylindrical external hexagon (HE) and morse cone (CM) implants. 43 implants were installed in edentulous areas of 20 selected patients following predefined inclusion and exclusion criteria. Immediately after installing the implants (t1), insertion torque, resonance frequency, digital periapical radiograph and peri-implant evaluation were measured. These measurements were performed again after osseointegration (t2), and the data obtained were analyzed statistically, with specific tests for each type of analysis and a significance level of 5%. The results showed that the ISQ values when measured using the resonance frequency analysis (AFR) were similar for cylindrical HE and CM implants. The stability of these implants was influenced by the insertion torque (lower torques provided an increase in secondary stability) and bone recipient type (HE implants installed in type II and IV bone and CM implants installed in type II and III bones showed an increase in secondary stability). Peri-implant bone loss, provided that within normal standards, did not influence the primary and secondary stability of these implants. Thus, our studies recommend that exploring and developing AFR as a method of assessing implant stability should be a still necessary search for scientific research to better understand the behavior of dental implants, in their different moments and situations in the oral cavity, as well as determine a good level of stability that consequently would determine greater longevity and functionality of dental implants(AU)

Efectividad de los métodos radiográficos periapicales por paralelismo y bisección / Effectiveness of periapical radiographic methods by parallelism and bisection

RESUMEN Introducción: la radiografía periapical constituye el método clásico y más empleado en Estomatología. Se puede realizar con dirección bisectal o por paralelismo; esta última alcanza una generalización y eficacia marcada, debido al desarrollo de sistemas posicionadores y de enfoque de la película. Objetivo: determinar la efectividad de los métodos radiográficos periapicales por bisección y paralelismo, en la Clínica Estomatológica Docente Antonio Briones Montoto. Métodos: se realizó un estudio descriptivo transversal, entre diciembre 2017 y abril 2018, en el Departamento de Radiología de la clínica estomatológica seleccionada en una muestra de 80 pacientes, a los que se le realizó una radiografía periapical por bisección y otra por paralelismo de región de bicúspides y/o molares superiores. Se compararon las imágenes obtenidas. Resultados: las imágenes parciales se produjeron en 12,5 y 4 % con bisección y paralelismo. Las distorsiones más frecuentes fueron las superposiciones del piso del seno maxilar y del cigomático a las raíces en un 45 y 26,5 % con dirección bisectal y de 10 y 5 % con paralelismo; mientras que la necesidad de repetir radiografías fue de un 25 y 6,25 %. Conclusiones: todas las imágenes producidas con el método periapical por paralelismo con la utilización de sistemas de Extensión de Cono Paralelo, presentaron un enfoque total, con escasas y leves distorsiones de las imágenes con ahorro, la necesidad de repetir radiografías fue mínima, además, resultó muy fácil de aprender y realizar por personal novel.

ABSTRACT Introduction: periapical radiography constitutes the classic and more used method in Dentistry, which can be carried out with bisectal direction or by parallelism, reaching this last one, a generalization and marked efficacy due to the development of system positioners and a coating approach. Objective: to determine the effectiveness of periapical radiographic methods by bisection and parallelism at Antonio Briones Montoto Dentistry Teaching Clinic. Methods: a cross-sectional descriptive study was carried out between December 2017 and April 2018 in the Radiology Department of the chosen dentistry clinic in a sample of 80 patients, who were given a periapical radiography by bisection and another by parallelism of the region of bicuspids and/or upper molars by trained students of the fourth academic-year of dentistry studies and comparing the images obtained. Results: partial images were produced in 12,5 % and 4 % with bisection and parallelism respectively. The most frequent distortions were the overlapping of the maxillary sinus and zygomatic floor to the roots in 45 and 26,5 % with bisectal direction, 10 and 5 % with parallelism; while the need to repeat X-rays was 25 and 6,25 % respectively. Conclusions: by the periapical and parallelism methods using XCP systems, all the images produced presented a total approach, with scarce and slight distortions of the images saving resources because the need to repeat X-rays was minimal, in addition, it was very easy to learn and perform by novel personnel.

More frequent detection of calcified carotid atherosclerotic plaques and mineralized laryngeal cartilages on digital than on film-based panoramic radiographs.

PURPOSE: To determine whether calcified carotid atherosclerotic plaques (CCAPs) and mineralized laryngeal cartilages (MLCs) were more frequently detected on digital or film-based panoramic radiographs. The clinical relevance of this question is that some radiopacities seen on digital radiographs may correspond to medium-density tissues that are not necessarily mineralized. MATERIALS AND METHODS: Data were collected from panoramic radiographs and the respective reports issued by 2 private oral radiology centers. A total of 388 radiographs and reports were divided into film-based (group A) and digital (group D) radiographs. The frequencies of CCAPs and MLCs were analyzed using the Fisher exact test, and odds ratios were also calculated (α=1%). RESULTS: The mean age of patients whose reports and radiographs showed CCAPs and/or MLCs ranged from 50.1 to 54.1 years. There was a predominance of females. A higher frequency of CCAPs and MLCs was observed in group D than in group A at both centers (P<0.01). CCAPs and MLCs were detected 4 times more frequently in group D than in group A at one of the centers. CONCLUSION: CCAPs and MLCs were more frequently detected on digital than on film-based panoramic radiographs. Further studies are needed to determine whether such radiopacities do indeed correspond to mineralized, rather than medium-density, tissues.