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Background: To determine the operative time and the internal restoration gap in the restoration-tooth interface in the cavity floor using an incremental technique for conventional resins and the single-increment technique for the bulk fill resin. Material and Methods: In this in vitro experimental study, the internal gaps of the restoration-tooth interfaces in the cavity floors of two conventional resins and two bulk fill resins were microscopically analyzed, and the restoration times of the single-increment technique and the incremental technique were determined. Results: Bulk fill resins had smaller internal gap (63.31 µm) than conventional resins (333.14 µm). Regarding the restoration time, the single-increment technique obtained the best results in operative time (3.52 minutes), with significant differences relative to the incremental technique. Conclusions: The Tetric N-Ceram bulk fill resin presented better performance than conventional resins relative to the internal gap of the restoration-tooth interface in the cavity floor. In addition, the single-increment technique presented a short clinical restoration time. Key words:Composite, internal gap, restoration technique.
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The Candida Albicans fungus in our body can cause various conditions and will depend directly on the systemic condition of the host. Patients with COVID-19 who have previously presented this fungus can increase the likelihood of morbidity and mortality, since this microorganism can be located in areas that correspond to the respiratory system, generating a functional deficit. If not treated timely, it will proliferate into the blood and digestive system. Many patients with respiratory difficulties on account of this condition require mechanical ventilation to combat it. Objective: To relate the presence of Candida Albicans as an aggravating factor in patients with COVID-19. Materials and: methods: A literature review took place using the Redalyc, Scielo, PubMed, Research gate, Science direct, Google Scholar databases. The inclusion criteria used were: articles in English and Spanish, along with articles published from 2020 up to date. There were 65 scientific articles that met the search criteria and were analyzed. The analysis determined that oral candidiasis negatively affects patients with COVID-19 infection, increasing the risk of admission to the ICU with the use of artificial ventilators.
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Background: Objective: To compare two in-vitro protocols to study the effect of simulated gastric acid on the mechanical properties of resins based composites(RBCs). Material and Methods: Three RBC FILTEK Supreme XTE (FS), BRILLIANT EverGlow (BE), GrandioSo (GS) were used. They were randomly divided into a control group (CG) and two groups exposed to simulated gastric acid: a 6-month daily protocol (DG) and an accelerated 90-min protocol (AG). Vickers microhardness (VH) and flexural strength were evaluated at baseline and six months. Statistical analysis was performed using repeated measures ANOVA tests for VH and three-way for flexural strength data (α=0.05). Results: Daily exposure in the CG and DG groups caused a reduction in VH values and flexural strength (p<0.05). The majority of values in the AG remained stable, after an exposure of 90 min; FS (p=0.118) and GS (p=0.729) in VH and FS (p=0.377), BE (p=0.692) and GS (p=0.672) in flexural strength. Conclusions: Daily exposure during 6 months caused significant changes in the VH values and flexural strength of the RBCs. The acid-accelerated protocol did not cause the same magnitude of change in VH values and flexural strength seen at six months of daily exposure. Key words:Gastric acid, hardness, composite resins, flexural strength, dental materials.
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Abstract: La impresión intraoral permite al odontólogo obtener directamente los datos de las piezas dentales que se requiera rehabilitar, otorgándole mayor precisión y eliminando así de la fase clínica la toma de impresión y la fabricación del modelo, aspectos sensibles a errores. El objetivo de la presente revisión es identificar el sistema de impresión digital intraoral más preciso y además identificar los factores que afectan a la precisión de esta en odontología restauradora. Mediante una revisión bibliográfica con búsqueda en las bases de datos de PubMed y Embase se obtuvieron 153 artículos, luego de la evaluación cualitativa se incluyeron en la revisión 14 que cumplieron con los criterios de inclusión y exclusión. Se determinó que la experiencia del dentista, la convergencia en la preparación dental y la terminación cervical son determinantes al momento de la toma de impresión digital, sin embargo, el uso o no de polvo no es relevante. El sistema de impresión digital Lava C.O.S., iTero y True definition son los más precisos dependiendo siempre del tipo de rehabilitación a realizar.
Abstract: Digital impresión allows the dentist to directly obtain the data of the dental pieces that neet to be rehabilitated, giving it greater precisión and thus eliminating the impression and manufacturing of the dental model, error-sensitive aspects of the clinical phase. The aim of this review is to identify the most accurate intraoral digital impression system and identifiy the factors that affect the accuracy in the restorative dentistry. Through a bibliographic review with search in PubMed and Embase databases, 153 articles were obtained, after qualitative evaluation they were included in the revisión 14 that met the inclusion and exclusion criteria. It was determined that the experience of the dentist, the convergence in the dental preparation and the cervical termination are decisive at the accuracy of the digital impression, however, the use or not of dust is not relevant. The Lava C.O.S., iTero and True definition are the most accurate always depending on the type of rehabilitation to be performed.
Subject(s)
Dental Impression Technique/instrumentation , DermatoglyphicsABSTRACT
La presencia de la nueva pandemia COVID-19 o SARS-CoV-2 evidencia la necesidad de adoptar medidas que minimicen, prevengan y controlen el riesgo de infección y la propagación del virus en la práctica odontológica. Por lo cual, el objetivo de este artí-culo es establecer las repercusiones en los distintos ámbitos de la atención odontológica ante la presencia del virus, en relación con la práctica de control de infecciones denta-les, las características de contagio de este (en los diferentes escenarios estomatológicos), los procedimientos odontológicos y las posibles consideraciones durante la pandemia. Concluyendo que en la práctica odontológica se debe priorizar los procedimientos de emergencia a aquellos pacientes sin síntomas respiratorios además de la evaluación previa para descartar cualquier sintomatología relacionada con el virus, precautelando la salud de profesionales y pacientes que interactúan durante la consulta odontológica.
The presence of the new pandemic COVID-19 or SARS-CoV-2 shows the need to adopt measures that minimize, prevent, and control the risk of infection and the spread of the virus in dental practice. Therefore, the objective of this article is to establish the repercus-sions in different areas of dental care facing the presence of the virus, in relation to the practice of dental infection control, its contagion characteristics (in different stomato-logical scenarios), dental procedures and possible considerations during the pandemic. Concluding that in dental practice, emergency procedures should be prioritized to those patients without respiratory symptoms in addition to the prior evaluation to rule out any symptomatology related to the virus, protecting the health of professionals and patients who interact during the dental consultation.
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RESUMEN Introducción: La prevalencia de condiciones patológicas que se presentan como radiopacidades a nivel de los tejidos blandos en radiografias panorámicas es una problemática que se da a nivel mundial de la población, siendo este hallazgo radiográfico el diagnóstico inicial de otras afecciones sistémicas. Objetivo: el objetivo de esta investigación fue identificar la frecuencia de radiopacidades mineralizadas que se encuentran a nivel de los tejidos blandos en radiografías panorámicas. Metodología: se analizó 347 radiografías de pacientes mayores de 20 años atendidos en la Clínica Docente Odontológica de la Universidad Católica de Cuenca, Sede Azogues, Ecuador desde diciembre del 2017 hasta mayo del 2018. Resultados: se encontró una prevalencia del 0% de tonsilolitos y anteromas, 1% de ganglios linfáticos calcificados y de antrolitos, 2% de sialolitos, 4% de calcificaciones del ligamento estilohioideo unilateral, 23% de calcificaciones del ligamento estilohioideo bilateral y 65% no presentaron calcificaciones de los tejidos blandos. Conclusión: se pudo identificar que las radiopacidades más frecuentes a nivel de los tejidos blandos es el del proceso estilohioideo calcificado bilateral.
ABSTRACT Introduction: The prevalence of pathological conditions that appear as radiopacities at the level of the soft tissues in panoramic radiographs is a problem that occurs worldwide in the population, being this radiographic finding the initial diagnosis of other systemic affections. Objectives: the aim of this research was to identify the frequency of mineralized radiopacities that are found at the soft tissue level in panoramic radiographs. Material and methods: it was analyzed 347 radiographs of patients over 20 years of age, treated in the "Clínica Docente Odontológica" of the Universidad Católica de Cuenca, Sede Azogues, Ecuador from December 2017 to may 2018. Results: a prevalence of 0% of tonsillolith and atheroma was found, 1% of calcified lymph nodes and of electrolytes, 2% of sialolith, 4% of unilateral stylohyoid ligament calcification, 23% of calcification of bilateral stylohyoid ligament and 65% did not present calcifications of the soft tissues. Conclusion: it was possible to identify that the most frequent radiopacity at soft tissue level is the calcified bilateral stylohyoid process.
Subject(s)
Tooth Calcification , Radiography, PanoramicABSTRACT
STATEMENT OF PROBLEM: The accuracy of digital scanners is acceptable for scanning a complete dental arch. However, whether that accuracy is sufficient for only 1 tooth within the dental scan of a complete dental arch is unclear. PURPOSE: The purpose of this in vitro study was to evaluate and compare the accuracy of 4 intraoral scanners on a complete dental arch and on prepared teeth digitally isolated from the digital scan in terms of trueness and precision. MATERIAL AND METHODS: A model of a complete dental arch with tooth preparations was scanned 40 times with each of the 4 digital scanners. Their accuracy was evaluated by using 3-dimensional (3D) software to compare the test models with a highly accurate reference model. The data were digitally processed to isolate the prepared teeth and evaluate them in the same way. The data were statistically analyzed using the Levene test and the Tamhane's T2 test (α=.05). RESULTS: In scans of a complete dental arch, the True Definition scanner had the best accuracy values, followed by TRIOS, iTero, and Omnicam. For prepared teeth isolated from the dental arch, both True Definition and TRIOS had the best values, followed by iTero and Omnicam. CONCLUSIONS: In both long-span scans of the complete dental arch and isolated prepared teeth, the True Definition scanner had the greatest accuracy, closely followed by TRIOS.
Subject(s)
Dental Arch , Tooth , Computer-Aided Design , Dental Impression Technique , Imaging, Three-Dimensional , Models, Dental , SoftwareABSTRACT
[This corrects the article DOI: 10.1371/journal.pone.0202916.].
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STATEMENT OF PROBLEM: Although there are specific and general digital scanning guidelines depending on the system used, it is important to have the necessary flexibility in the acquisition of three-dimensional (3D) images to adapt to any clinical situation without affecting accuracy. PURPOSE: The purpose of this in vitro study was to identify and compare the scanning strategy with the greatest accuracy, in terms of trueness and precision, of four intraoral scanners in the impression of a complete dental arch. MATERIAL AND METHODS: Four digital scanners were evaluated with a 3D measuring software, using a highly accurate reference model obtained from an industrial scanner as a comparator. Four scanning strategies were applied 10 times on a complete maxillary arch cast inside a black methacrylate box. The data were statistically analyzed using one-way analysis of variance (ANOVA) and post hoc comparisons with Tamhane T2 test. RESULTS: The trueness of the Trios and iTero system showed better results with strategy "D," Omnicam with strategy "B," and True Definition with strategy "C". In terms of precision, both iTero and True Definition showed better results with strategy "D", while Trios showed best results with strategy "A" and Omnicam with strategy "B". There were significant differences between the scanning strategies (p<0.05) with the iTero scanner, but not with the other scanners (p>0.05). CONCLUSIONS: The digital impression systems used in the experiment provided sufficient flexibility for the acquisition of 3D images without this affecting the accuracy of the scanner.
Subject(s)
Dental Arch/diagnostic imaging , Imaging, Three-Dimensional/instrumentation , Imaging, Three-Dimensional/methods , Dental Impression Technique , Epoxy Resins , Humans , In Vitro Techniques , Reproducibility of Results , SoftwareABSTRACT
BACKGROUND: The scanner does not measure the dental surface continually. Instead, it generates a point cloud, and these points are then joined to form the scanned object. This approximation will depend on the number of points generated (resolution), which can lead to low accuracy (trueness and precision) when fewer points are obtained. The purpose of this study is to determine the resolution of four intraoral digital imaging systems and to demonstrate the relationship between accuracy and resolution of the intraoral scanner in impressions of a complete dental arch. MATERIAL AND METHODS: A master cast of the complete maxillary arch was prepared with different dental preparations. Using four digital impression systems, the cast was scanned inside of a black methacrylate box, obtaining a total of 40 digital impressions from each scanner. The resolution was obtained by dividing the number of points of each digital impression by the total surface area of the cast. Accuracy was evaluated using a three-dimensional measurement software, using the "best alignment" method of the casts with a highly faithful reference model obtained from an industrial scanner. Pearson correlation was used for statistical analysis of the data. RESULTS: Of the intraoral scanners, Omnicam is the system with the best resolution, with 79.82 points per mm2, followed by True Definition with 54.68 points per mm2, Trios with 41.21 points per mm2, and iTero with 34.20 points per mm2. However, the study found no relationship between resolution and accuracy of the study digital impression systems (P >0.05), except for Omnicam and its precision. CONCLUSIONS: The resolution of the digital impression systems has no relationship with the accuracy they achieve in the impression of a complete dental arch. The study found that the Omnicam scanner is the system that obtains the best resolution, and that as the resolution increases, its precision increases. Key words:Trueness, precision, accuracy, resolution, intraoral scanner, digital impression.
