Braided Glass Fiber Reinforced Composite Resin Bridge - An Alternative Treatment for Management of Missing Anterior Tooth: A Case Report

Missing anterior teeth is of great concern during a patient's lifetime in many communities. A variety of treatment options, from implants to traditional bridges are often used in order to replace missing anterior tooth. However, it is often accompanied by variety of barriers such as an increased number of chairside visits and better costs. Fibre-reinforced composites (FRCs) have gained increasing and great acceptance in mainstream prosthodontics as viable alternatives to alloy-based restorations recently. In compaison to other restorative systems this is often a conservative approach that carries a minimum risk of pulp exposure or sensitivity and periodontal inflammation, which maintains the health of supporting tissues. Therefore the aim of this case report was to present a clinical case of a congenitally missing mandibular central incisors bilaterally which were replaced by means of a FRC bridge wherein, we employed a semi-direct (direct and indirect) technique. This technique provides a conservative, esthetic, and noninvasive treatment, economically more acceptable, nonirritating, and noniatrogenic. FRC bridges can therefore be considered as a permanent treatment modality.

Absorption instruments inter-comparison campaign at the Arctic Pallas station

Aerosol light absorption was measured during a 1-month field campaign in June–July 2019 at the Pallas Global Atmospheric Watch (GAW) station in northern Finland. Very low aerosol concentrations prevailed during the campaign, which posed a challenge for the instruments' detection capabilities. The campaign provided a real-world test for different absorption measurement techniques supporting the goals of the European Metrology Programme for Innovation and Research (EMPIR) Black Carbon (BC) project in developing aerosol absorption standard and reference methods. In this study we compare the results from five filter-based absorption techniques – aethalometer models AE31 and AE33, a particle soot absorption photometer (PSAP), a multi-angle absorption photometer (MAAP), and a continuous soot monitoring system (COSMOS) – and from one indirect technique called extinction minus scattering (EMS). The ability of the filter-based techniques was shown to be adequate to measure aerosol light absorption coefficients down to around 0.01 Mm−1 levels when data were averaged to 1–2 h. The hourly averaged atmospheric absorption measured by the reference MAAP was 0.09 Mm−1 (at a wavelength of 637 nm). When data were averaged for >1 h, the filter-based methods agreed to around 40 %. COSMOS systematically measured the lowest absorption coefficient values, which was expected due to the sample pre-treatment in the COSMOS inlet. PSAP showed the best linear correlation with MAAP (slope=0.95, R2=0.78), followed by AE31 (slope=0.93). A scattering correction applied to PSAP data improved the data accuracy despite the added noise. However, at very high scattering values the correction led to an underestimation of the absorption. The AE31 data had the highest noise and the correlation with MAAP was the lowest (R2=0.65). Statistically the best linear correlations with MAAP were obtained for AE33 and COSMOS (R2 close to 1), but the biases at around the zero values led to slopes clearly below 1. The sample pre-treatment in the COSMOS instrument resulted in the lowest fitted slope. In contrast to the filter-based techniques, the indirect EMS method was not adequate to measure the low absorption values found at the Pallas site. The lowest absorption at which the EMS signal could be distinguished from the noise was >0.1 Mm−1 at 1–2 h averaging times. The mass absorption cross section (MAC) value measured at a range 0–0.3 Mm−1 was calculated using the MAAP and a single particle soot photometer (SP2), resulting in a MAC value of 16.0±5.7 m2 g−1. Overall, our results demonstrate the challenges encountered in the aerosol absorption measurements in pristine environments and provide some useful guidelines for instrument selection and measurement practices. We highlight the need for a calibrated transfer standard for better inter-comparability of the absorption results.

Restorative Treatment of Amelogenesis Imperfecta with Prefabricated Composite Veneers

This case report presents the use of prefabricated composite veneers for restorative treatment of amelogenesis imperfecta (AI). This technique bridges the gap between a conventional direct technique and a conventional indirect technique and introduces an alternative semidirect restorative technique for AI patients. The aim of this case report is to describe restoration of a young girl with severe AI using prefabricated composite veneers and to discuss the benefits and limitations of this technique compared to the alternative restorative techniques.

Indirect determination of airflow resistance of textiles with reference samples

Airflow resistance is a non-acoustic parameter of great relevance in the acoustic characterization of porous materials. It is used in several sound absorbing material prediction models and it is also a control parameter for acoustic conditioning and insulation in different building solutions. The ISO 9053 standard defines several methods to obtain it, using both direct measurements and indirect techniques. However, both procedures may involve problems related to the placement of the textile samples in the tube or to the stability of the samples during testing. In this work, the use of reference materials to stabilize the measurement of thin materials is proposed. Airflow resistance results obtained for different materials in an impedance tube are presented. The tests have been carried out by following the Ingard & Dear method, as an indirect technique accepted by the standard. Several material compositions with a wide range of airflow resistance values have been analyzed with different reference materials.

Impact Socio-économique de l’Introduction du Filet Maillant sur les Conditions de Vie des Communautés Riveraines du lac Kivu : Cas des Pêcheurs et Femmes Marchandes de Limnothrissa Miodon dans la Ville de Bukavu

La pêche au filet maillant joue un rôle considérable dans l’amélioration des conditions de vie des communautés riveraines du lac Kivu. L’introduction de cette technique de pêche au filet maillant est un mécanisme d'emploi et de survie pour au moins dix mille (10.000) personnes dont les pêcheurs, les femmes marchandes et leurs dépendants. Le présent article a pour objectif d'analyser l’impact de l'introduction du filet maillant sur les conditions de vie des communautés riveraines du lac Kivu. La technique documentaire a permis de consulter les études antérieures réalisées sur l’impact de l’introduction du filet maillant sur le lac Kivu au sein des communautés locales. Ainsi, le caractère empirique de l’étude a exigé l’usage de la technique de l’entretien pour collecter les informations d’ordre qualitatif. Le questionnaire administré à 89 enquêtés par la technique indirecte a permis de collecter les informations d’ordre quantitatif que nous avons analysées à l’aide du logiciel statistique pour les sciences sociales (SPSS). Les données qualitatives ont été codées pour la quantification du sens que les enquêtés donnent à l’importance du filet maillant. Ce sont les approches qualitative et quantitative qui ont été utilisées pour analyser l’impact socio-économique de l’introduction du filet maillant sur les conditions de vie des communautés riveraines du lac Kivu. En effet, les résultats obtenus montrent que la première retombée de l’introduction du filet maillant est la création d'emplois, l'augmentation de la production, l’amélioration de la sécurité alimentaire telle qu’affirmé respectivement par 91,01%, 82,2% et 74,15%. L'amélioration des conditions de vie et le renforcement de la cohésion sociale ont été affirmés, respectivement par 93,25% et 77,52% d’enquêtés. Ces affirmations ont été appuyées par le rapport final du projet pêche qui a également aidé les pêcheurs à se constituer en comités de pêcheurs. Du côté des femmes, les marchandes s'organisent en tontine où elles échangent entre elles et cherchent des solutions à leurs différends. Et en dernier lieu, c'est la création de plusieurs marchés de Limnothrissa Miodon qui a été évoquée par 79,77% et qui s'explique par la multiplication des unités de pêche qui sont à la recherche de lieux proches des populations afin d'écouler leurs produits. Toutefois, l’étude a révélé que l’insécurité affirmée par 60,67% d’enquêtés et le travail des enfants affirmé par 92,13% d’enquêtés sont les conséquences néfastes de l’introduction du filet maillant dans le lac Kivu. Gillnet fishing plays a significant role in improving the living conditions of communities bordering Kivu Lake. The introduction of this gillnet fishing technique is a mechanism of employment and survival for at least ten thousand (10,000) people including fishermen, women traders and their dependents. The purpose of this paper is to analyze the impact of the introduction of the gillnet on the living conditions of communities bordering Kivu Lake. The documentary technique made it possible to consult previous studies carried out on the impact of the introduction of the gillnet on Kivu Lake on local communities. Thus, the empirical nature of the study required the use of the interview technique to collect qualitative data. The questionnaire administered to 89 respondents by the indirect technique collected the quantitative information that we analyzed using statistical software for the social sciences (SPSS). Qualitative data was coded to quantify the meaning respondents gave to the importance of the gillnet. Qualitative and quantitative approaches were used to analyze the socio-economic impact of the introduction of the gillnet on the living conditions of communities bordering Kivu Lake. Indeed, the results obtained show that the first impact of the introduction of the gillnet is the creation of jobs, the increase in production, the improvement of food security as affirmed respectively by 91.01%, 82.2% and 74.15%. The improvement of living conditions and the strengthening of social cohesion were affirmed, respectively by 93.25% and 77.52% of respondents. These statements were supported by the final report of the fishing project which also helped fishermen to form fishermen's committees. On the women's side, the merchants organize themselves in a tontine where they exchange ideas with one another and seek solutions to their conflicts. And lastly, it is the creation of several Limnothrissa Miodon markets which was mentioned by 79.77% and which is explained by the multiplication of fishing units which are looking for places close to the populations in order to sell their products. However, the study revealed that insecurity affirmed by 60.67% of respondents and child labor affirmed by 92.13% of respondents are the harmful consequences of the introduction of the gillnet in Kivu Lake.

Direct-Indirect Technique Restoration for Non-Carious Cervical Lesions Treatment: a Case Report

Non-Carious Cervical Lesions are characterized by slow and progressive loss of hard tissue at the level of enamel-cement junction, without bacterial involvement. This work aimed to address a case report of restorative treatment in Class V cavities in multiple premolars using the direct-indirect technique with composite resin. A 42 year-old male patient presented for esthetic restorative treatment with the complaint of severe dentin hypersensitivity and wedged-shaped non-carious cervical lesions affecting the maxillary premolars. The restorative treatment chosen was a direct-indirect technique with composite performed into three sessions as follows: making the class V composite inlays, cementation, and final polishing. The direct-indirect technique as an alternative to the traditional direct technique has the benefits of a better contour of the restoration, since the finishing and polishing are made extraorally. Besides, the control of the polymerization stress and less discomfort to the patient are other advantages. In the case of direct-indirect class V restoration, the advantages far surpass those of the direct technique. Keywords: Hypersensitivity. Tooth Wear. Composites Resins ResumoAs Lesões Cervicais Não Cariosas se caracterizam pela perda lenta e progressiva de tecido duro próximo a junção cemento-esmalte, sem envolvimento bacteriano. Este trabalho tem o objetivo de relatar um caso clínico de tratamento restaurador em cavidades do tipo Classe V em pré-molares pela técnica direta-indireta com resina composta. Paciente do sexo masculino, 42 anos, queixava-se de forte sensibilidade e múltiplas Lesões Cervicais Não Cariosas na forma de cunha nos pré-molares superiores. O tratamento restaurador escolhido foi a técnica direta-indireta com resina composta realizado em três sessões distribuídas em confecção da peça em resina composta, cimentação e polimento final. A técnica direta-indireta surge como alternativa a técnica direta tradicional trazendo como benefícios um melhor contorno da restauração, uma vez que esta é acabada e polida fora da boca, além do controle do estresse de polimerização e menor desconforto ao paciente. A intervenção restauradora direta-indireta se mostra eficaz devido ao fato de conseguir contornar dificuldades encontradas em técnicas restauradoras diretas. Palavras-chave: Hipersensibilidade. Desgaste dos Dentes. Resinas Compostas

Anterior teeth rehabilitation with direct resin composite veneer using multiple layering technique: A case report

Cosmetic veneer has become a popular option for patients seeking to improve aesthetic in their smile. The procedure can be done through a direct or indirect technique which differs in term of material used and laboratory involvement. Despite producing a better aesthetic result than its direct technique counterpart, high-cost treatment, multiple visit requirement and invasive nature of tooth preparation are proven to be a stumbling block to the patient in some cases to choose indirect technique. Therefore, direct composite veneer technique can be offered due to its low costing and conservative concept which advocates more tooth structure preservation. This case report is about direct composite veneer for anterior teeth rehabilitation and its simple and conservative protocol.

Factors Affecting The Indirect Immunoperoxidase Staining Of Infectious Bursal Disease Virus Antigens In Cells

THE application of the Immunoperoxidase (IP) antibody technique for the definitive diagnosis of Infectious Bursal Disease (IBD) in chickens has earlier been described (Okeke and Lang, 1982). During that study it was noted that the Indirect method of IP was more sensitive in the demonstration of IBD viral antigens than the direct method. Consequently, more formation was sought on the specific technical parameter and the consequences that resulted by deviations from the codified procedures employed in the Indirect technique with the aim of obtaining an even better result. Studies of pH, serum dilutions, serum incubation time, conjugate dilutions, conjugate incubation time and developing time were conducted to find out what Influence such factors could have on the final staining product.

Mathematical Modelling, Analysis and Control of a Three to Five-Phase Matrix Converter for Minimal Switching Losses

The interest in motor drive systems with a number of phases greater than three has increased, mainly in high-power industrial fields due to their advantages compared with three-phase drive systems. In this paper, comprehensive mathematical modeling of a five-phase matrix converter (MC) is introduced. Besides that, the direct and indirect space vector modulation (SVM) control methods are compared and analyzed. Furthermore, a mathematical model for the MC with the transformation between the indirect and direct topology is constructed. The indirect technique is used to control the five-phase MC with minimum switching losses. In this technique, SVM deals with a five-phase MC as a virtual two-stage converter with a virtual DC link (i.e., rectifier and inverter stages). The voltage gain is limited to a value of 0.79. Moreover, to analyze the effectiveness of the control technique and the advantages of the MC, a static R-L load is employed. However, the load can also be an industrial load, such as hospital pumping or vehicular applications. The presented analysis proves that the MC gives a wide range of output frequencies, and it has the ability to control the input displacement factor and the output voltage magnitude. In addition, the absence of the massive DC link capacitors is an essential feature for the MC, resulting in increased reliability and a reduced size converter. Eventually, an experimental validation is conducted on a static load to validate the presented model and the control method. It is observed that good matching between the simulation and the experimental results is achieved.