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.

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.

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.

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 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.

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)

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.

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.

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.

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.

Comparison of the Accuracy of Digital Radiography with Conventional Radiography and Visual Examination in the Detection of Permanent Teeth Interproximal Caries

Objective: To compared the accuracy of digital radiography in the diagnosis of interproximal caries in permanent teeth with conventional radiography and visual examination. Material and Methods: In this descriptive-analytical study, 78 human premolars, which seem normal in primary examination, are mounted on the plaster in a pair-wise manner and their caries are visually evaluated. Conventional and digital radiographic images are taken under the same conditions and their caries are graded with Confidence Score. To determine the golden standard, after mesiodistal incision, the teeth are examined using stereomicroscopy. Finally, the results obtained by visual observation and conventional radiography as well as digital images were compared with those obtained from the stereomicroscopy to determine their accuracy in detecting the interproximal caries. Results: The consistencies between the visual, digital, and conventional methods with the standard method (microscopic histology) are 53%, 78%, and 50% respectively - all of them are significant (p<0.05). The highest and the lowest sensitivities are related to the digital (96%) and visual (88%) methods respectively, while the highest and lowest specificities are related to the digital (79%) and conventional (50%) methods respectively. The highest and lowest positive predictive value is related to the digital (79%) and conventional (80%) methods respectively. The highest and lowest negative predictive values are related to the digital (90%) and visual (71%) methods respectively. Compared with the standard methodology, the most accurate diagnostic accuracy can be seen for the digital method (91%). Conclusion: There is no significant difference in the diagnosis of interproximal caries by different methods, and the only advantage of digital radiography, compared with the conventional one, is storing radiographs without losing important information and the lower dose of radiation for the patient.

Detection of peri-implant bone defects using cone-beam computed tomography and digital periapical radiography with parallel and oblique projection

PURPOSE: To compare the diagnostic accuracy of cone-beam computed tomography (CBCT) with that of parallel (PPA) and oblique projected periapical (OPA) radiography for the detection of different types of peri-implant bone defects.MATERIALS AND METHODS: Forty implants inserted into bovine rib blocks were used. Thirty had standardized bone defects (10 each of angular, fenestration, and dehiscence defects), and 10 were defect-free controls. CBCT, PPA, and OPA images of the samples were acquired. The images were evaluated twice by each of 2 blinded observers regarding the presence or absence and the type of the defects. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were determined for each radiographic technique. The 3 modalities were compared using the Fisher exact and chi-square tests, with P<0.05 considered as statistical significance.RESULTS: High inter-examiner reliability was observed for the 3 techniques. Angular defects were detected with high sensitivity and specificity by all 3 modalities. CBCT and OPA showed similar AUC and sensitivity in the detection of fenestration defects. In the identification of dehiscence defects, CBCT showed the highest sensitivity, followed by OPA and PPA, respectively. CBCT and OPA had a significantly greater ability than PPA to detect fenestration and dehiscence defects (P<0.05).CONCLUSION: The application of OPA radiography in addition to routine PPA imaging as a radiographic follow-up method for dental implantation greatly enhances the visualization of fenestration and dehiscence defects. CBCT properly depicted all defect types studied, but it involves a relatively high dose of radiation and cost.

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.

Efficacy of digital radiographic systems in the quality assessment of intracanal materials used for primary teeth

Aim: To evaluate the performance of three digital radiographic systems in the analysis of root canal filling quality using different intracanal materials for primary teeth. Methods: Twenty-five bovine teeth were divided into 5 groups: Calen® combined with iodoform; Calen® combined with zinc oxide; zinc oxide and eugenol; UltraCal®XS, and 2% chlorhexidine combined with Ca(OH)2 + zinc oxide. Periapical radiographs were obtained with the VistaScan, Express, and SnapShot systems. The quality of the images was evaluated objectively (radiopacity) and subjectively (apical sealing and filling homogeneity). As the reference standard, the teeth were scanned with a micro-CT device. Results: Radiopacity differed among the radiographic systems and materials tested. In general, the greatest difference was observed between the Express and VistaScan systems; Calen® combined with iodoform resulted in the highest radiopacity. The radiographic systems did not differ in terms of homogeneity. However, Calen® combined with iodoform differed from the other materials and exhibited the best results. Regarding apical sealing, the SnapShot system and Calen® combined with zinc oxide provided the best results. Conclusion: Direct digital systems show better performance in evaluating the quality of endodontic treatment in primary teeth and should be preferred for this purpose

A pilot clinical study of immediate provisionalization with a chairside computer aided design and computer aided manufacture monolithic crown for single tooth immediate implant placement / 中华口腔医学杂志

Objective@#To evaluate the primary clinical outcomes of immediate provisionalization with a monolithic crown utilizing a novel chairside computer aided design and computer aided manufacture (CAD/CAM) workflow for single tooth immediate implant placement.@*Methods@#This pilot study was a prospective within-subjects design. Thirteen consecutive patients were included and diagnosed with untreatable single incisor or premolar with fine general and local anatomical conditions. The trial was conducted at Department of Implantology, Peking University School and Hospital of Stomatology, Beijing, between January 2016 and June 2016. The teeth were extracted atraumatically and implants were immediately placed in the fresh sockets. Two screw-retained interim crowns were fabricated for the same site utilizing different workflows, a monolithic lithium disilicate (LS2) crown produced by CEREC (Sirona, Germany) chairside CAD/CAM system (CER group) and a manually fabricated resin crown utilizing conventional workflow (CONV group) respectively. The patients were blinded to the group allocation of the two interim crowns. After the clinical try-in for both crowns in a randomized sequence, the patients' level of satisfaction was assessed with a virtual analogue scale (VAS) questionnaire. The restorations chosen by patients themselves were seated in the implants by one experienced prosthodontist. The accuracy, aesthetic effect and clinical time consumption of both groups were compared. Statistical analyses were performed with the Wilcoxon signed rank test.@*Results@#All patients were treated with atraumatic tooth extraction, immediate implant placement using flapless surgery and immediate provisionalization in a single visit. The interim crowns of both groups could be fitted with or without slight adjustments. For each patient, the interim crown of CER group was chosen to be seated with a relatively higher VAS result. The white esthetic score (WES) results demonstrated no statistically significant difference between CER group (7.5±1.1) and CONV group (7.9±0.9) (P>0.05). The mean total work time was significantly different resulting in (131.9±5.0) min for CER group and (205.2±6.3) min(P<0.05). The major difference lied in the laboratory work time, resulting in (113.5±6.3) min for CER group which was significantly shorter than (185.6±6.6) min for CONV group. As for impression taking time, the CER group (7.5±0.8) min was significantly shorter than CONV group (11.7± 1.1) min (P<0.05). However, analysis for clinical adjustment time showed a significantly longer time for CER group [(11.0±2.1) min vs (8.0±2.8) min, P<0.05]. After 3-6 months of observation, the overall survival rate was 100%. Screw loosening occurred in 4 patients and was tightened again. No other major complication soccurred.@*Conclusions@#The full digital workflow utilizing CEREC chairside CAD/CAM system to fabricate interim crowns after immediate implant placement in one single visit was feasible. It was more time-efficient and could effectively shorten the laboratory work time compared to the conventional workflow. Patients demonstrated high satisfaction and there was no statistical difference in WES results compared to the conventional workflow. Favorable clinical outcomes were gained in this short-term follow-up study.

Cone-beam computed tomography versus digital periapical radiography in the detection of artificially created periapical lesions: A pilot study of the diagnostic accuracy of endodontists using both techniques

PURPOSE: The aim of this study was to compare the diagnostic accuracy of previously trained endodontists in the detection of artificially created periapical lesions using cone-beam computed tomography (CBCT) and digital periapical radiography (DPR). MATERIALS AND METHODS: An ex vivo model using dry skulls was used, in which simulated apical lesions were created and then progressively enlarged using #1/2, #2, #4, and #6 round burs. A total of 11 teeth were included in the study, and 110 images were obtained with CBCT and with an intraoral digital periapical radiographic sensor (Instrumentarium dental, Tuusula, Finland) initially and after each bur was used. Specificity and sensitivity were calculated. All images were evaluated by 10 previously trained, certified endodontists. Agreement was calculated using the kappa coefficient. The accuracy of each method in detecting apical lesions was calculated using the chi-square test. RESULTS: The kappa coefficient between examiners showed low agreement (range, 0.17-0.64). No statistical difference was found between CBCT and DPR in teeth without apical lesions (P=.15). The accuracy for CBCT was significantly higher than for DPR in all corresponding simulated lesions (P<.001). The correct diagnostic rate for CBCT ranged between 56.9% and 73.6%. The greatest difference between CBCT and DPR was seen in the maxillary teeth (CBCT, 71.4%; DPR, 28.6%; P<.01) and multi-rooted teeth (CBCT, 83.3%; DPR, 33.3%; P<.01). CONCLUSION: CBCT allowed higher accuracy than DPR in detecting simulated lesions for all simulated lesions tested. Endodontists need to be properly trained in interpreting CBCT scans to achieve higher diagnostic accuracy.

Repeat analysis of intraoral digital imaging performed by undergraduate students using a complementary metal oxide semiconductor sensor: An institutional case study

PURPOSE: This study was performed to quantify the repeat rate of imaging acquisitions based on different clinical examinations, and to assess the prevalence of error types in intraoral bitewing and periapical imaging using a digital complementary metal-oxide-semiconductor (CMOS) intraoral sensor. MATERIALS AND METHODS: A total of 8,030 intraoral images were retrospectively collected from 3 groups of undergraduate clinical dental students. The type of examination, stage of the procedure, and reasons for repetition were analysed and recorded. The repeat rate was calculated as the total number of repeated images divided by the total number of examinations. The weighted Cohen's kappa for inter- and intra-observer agreement was used after calibration and prior to image analysis. RESULTS: The overall repeat rate on intraoral periapical images was 34.4%. A total of 1,978 repeated periapical images were from endodontic assessment, which included working length estimation (WLE), trial gutta-percha (tGP), obturation, and removal of gutta-percha (rGP). In the endodontic imaging, the highest repeat rate was from WLE (51.9%) followed by tGP (48.5%), obturation (42.2%), and rGP (35.6%). In bitewing images, the repeat rate was 15.1% and poor angulation was identified as the most common cause of error. A substantial level of intra- and interobserver agreement was achieved. CONCLUSION: The repeat rates in this study were relatively high, especially for certain clinical procedures, warranting training in optimization techniques and radiation protection. Repeat analysis should be performed from time to time to enhance quality assurance and hence deliver high-quality health services to patients.

Comparison of periapical radiography and cone-beam computed tomography in en-dodontic treated teeth for assessment of periapical lesions / 北京大学学报(医学版)

Objective:To compare the assessments of the presence or absence and the changes of post-treatment periapical lesions using periapical radiographs versus cone-beam computed tomography (CBCT).Methods:Imaging records were selected from a sample of 233 radiographic examinations (in-cluding periapical radiographs and CBCT)of patients with chronic apical periododontitis who received treatment and review in Department of Cariology and Endodontology of Peking University School of Stoma-tology.After testing the inter-observer and intra-observer agreement,two observers determined the pre-sence or absence of a periapical lesion and classified the changes of lesions in 4 categories:absence,re-duction or enlargement of lesion,or uncertain.The differences between CBCT and periapical radiographs in detecting the presence or absence and the changes of periapical lesions were compared using McNemar test and Fisher’s exact test respectively.Results:In the study,233 teeth were assessed with both periapi-cal radiographs and CBCT images.Periapical lesions were detected in 178 teeth on CBCT scans and in 146 teeth on periapical radiographs.CBCT images revealed a significantly larger number of lesions than were revealed by periapical radiographs (P <0.01 ).There was disagreement on the changes of lesions between the two radiological technologies in 25% teeth,and the difference was statistically significant (P <0.01 ). Conclusion:Significant differences were observed between periapical radiographs and CBCT in detection of post-treatment periapical lesions and assessment of the changes of periapical lesions.