Exploiting Nanomaterials for Optical Coherence Tomography and Photoacoustic Imaging in Nanodentistry.

There is already a societal awareness of the growing impact of nanoscience and nanotechnology, with nanomaterials (with at least one dimension less than 100 nm) now incorporated in items as diverse as mobile phones, clothes or dentifrices. In the healthcare area, nanoparticles of biocompatible materials have already been used for cancer treatment or bioimaging enhancement. Nanotechnology in dentistry, or nanodentistry, has already found some developments in dental nanomaterials for caries management, restorative dentistry and orthodontic adhesives. In this review, we present state-of-the-art scientific development in nanodentistry with an emphasis on two imaging techniques exploiting nanomaterials: optical coherence tomography (OCT) and photoacoustic imaging (PAI). Examples will be given using OCT with nanomaterials to enhance the acquired imaging, acting as optical clearing agents for OCT. A novel application of gold nanoparticles and nanorods for imaging enhancement of incipient occlusal caries using OCT will be described. Additionally, we will highlight how the OCT technique can be properly managed to provide imaging with spatial resolution down to 10's-100's nm resolution. For PAI, we will describe how new nanoparticles, namely TiN, prepared by femtosecond laser ablation, can be used in nanodentistry and will show photoacoustic microscopy and tomography images for such exogenous agents.

Identification of docosahexaenoic and eicosapentaenoic acids multiple targets facing periodontopathogens.

The eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) play a substantial role in Periodontal Disease (PD) due to their antimicrobial and immunomodulatory actions. However, their antimicrobial mechanism of action against bacteria involved in PD remains unclear. We aimed to estimate the probable targets of EPA and DHA against the seven periodontopathogens. Through in silico analyses, the protein-acids interactions, protein characterization, and molecular docking were performed. We identified 165 proteins from periodontopathogens that may interact with EPA and DHA. Fusobacterium nucleatum has the highest number of predicted proteins among analyzed bacteria (n = 43, 26.06%). The EPA shows more interactions than DHA. The EPA and DHA interact mainly with proteins involved in the metabolism (n = 69, 41.81%). Also, the EPA and DHA interact with proteins located in any subcellular location. The affinities between acids and pathogenic proteins were moderate (binding energy was lower than -4.0 kcal/mol). The interactions between EPA and DHA and periodontopathogens occur in multiples proteins. There is not a predilection about the functional class of pathogenic proteins targeting EPA and DHA. However, there are moderate binding affinities between EPA or DHA and essential pathogenic proteins (TolC, CRISPR, FusA).

Tratamento das retrações gengivais unitárias classes I e II de miller com matriz de colágeno xenógena: revisão de literatura / Treatment of single Miller class I and II gingival recessions with a xenogeneic collagen matrix: literature review

Objetivo: Verificar, através de uma revisão da literatura, a eficácia de uma matriz de colágeno xenógena associada ao retalho deslocado coronalmente no tratamento das retrações gengivais unitárias classes I e II de Miller. Materiais e métodos: A estratégia de busca das pesquisas foi realizada na base de dados MEDLINE pela combinações dos termos MESH e palavras-chave. Além disso, as bibliografias de todos os artigos incluídos e de revisões relevantes ao assunto foram consideradas para possível análise. Um mesmo pesquisador realizou as três fases da pesquisa. A primeira fase, a análise dos títulos, foi realizada para eliminar os materiais claramente irrelevantes ou que não tinham relação com o assunto abordado.A segunda fase, avaliação dos resumos dos artigos, foi baseada no tipo de estudo, característica da população/problema, intervenção e resultados obtidos. Na terceira fase, os textos completos selecionados para a revisão foram analisados e interpretados de acordo com os princípios da leitura crítica de artigos científicos. Resultados: Os estudos selecionados ficaram, assim, distribuídos: 05 (cinco) revisões sistemáticas, 12 (doze) ensaios clínicos randomizados, 02 (dois) estudos com modelo animal, (01) um estudo transversal observacional, 05 (cinco) séries de casos, 02 (dois) relatos de casos clínicos e 02 (duas) revisões de literatura, totalizando 29 (vinte e nove) artigos científicos. Conclusão: Por meio de uma revisão da literatura, constatou-se que a matriz de colágeno xenógena associada ao retalho deslocado coronalmente representa uma alternativa viável para o tratamento das retrações gengivais unitárias classes I e II de Miller, bem como proporciona satisfação estética aos pacientes.(AU)

Aim: To verify, through a review of the literature, the efficacy of a xenogeneic collagen matrix plus the coronally advanced flap in the treatment of Miller's class I and II single gingival recessions. Materials and methods: The studies` search strategy was carried out in the MEDLINE database through the combinations of the MESH terms and keywords. In addition, the bibliographies of all articles included and relevant reviews to the subject were considered for possible analysis. The same researcher carried out the three steps of the study. The first step, the analysis of the titles, was carried out to eliminate materials that were clearly irrelevant or had no relation to the subject addressed. The second, evaluation of the abstracts of the articles, was based on the type of study, characteristic of the population/problem, intervention and results obtained. In the third step, the complete texts selected for these review were analyzed and interpreted according to the principles of critical reading of scientific articles. Results: The selected studies were thus distributed: 05 systematic reviews, 12 randomized clinical trials, 02 animal model studies, 01 cross-sectional study, 05 case series, 02 clinical cases and 02 reviews of the literature, totaling 29 articles. Conclusion: Through a review of the literature, it was found that the xenogeneiccollagen matrix plus the coronally advanced flap represents a viable alternative in the treatment of Miller's class I and II single gingival recessions, as well as provides patients` aesthetic satisfaction.(AU)

Assessment of the Centralization of Root Canal Preparation with Rotary Systems.

OBJECTIVE: Apical deviations are important factors in endodontic therapy, since they can cause the treatment failure. The aim of the present study was to determine the centering capacity of ProTaper Universal™, Twisted File™ and Revo-S® rotary systems using cone beam computed tomography analysis before and after the instrumentation of root canals. MATERIALS AND METHODS: Thirty mesiobuccal roots from human lower first molars were divided into three groups of ten: Group 1 - ProTaper Universal™ Rotary System; Group 2 - Twisted File™ Rotary System; and Group 3 - Revo-S® Rotary System. All teeth were scanned using computed tomography to determine the condition of the root canal before and after instrumentation (4mm, 3mm and 2mm from the root apex). Images were made using ICAT VISION software for both instrumented and non-instrumented canals. RESULTS: The results were analyzed statistically using the Kolmogorov-Smirnov normality test for quantitative variables. Comparisons were made with two groups (Mann-Whitney - abnormal) and with more than two groups (Kruskal Wallis - abnormal). The level of significance was set at p<0.05. A statistically significant difference was found for the measurement of 4 mm between the "ProTaper Universal" and "Twisted File" systems. For the Twisted File system, a statistically significant difference was recorded between the measurements of 4mm and 3 mm. CONCLUSION: None of the assessed instruments was completely effective in terms of the biomechanical preparation of root canals since all created deviation from the original anatomy of the canal.

Correlação clínica e histopatológica de cistos e granulomas periapicais / A Clinical and Histopathological Correlation of Periapical Cysts and Granulomas

Cistos e granulomas periapicais estão entre as lesões radiolúcidas mais prevalentes. Porém, há situações em que os padrões clínicos e radiográficos se misturam e, portanto, o estudo histopatológico faz-se necessário para o diagnóstico definitivo. O objetivo deste estudo foi avaliar a correlação clínica e histopatológica no diagnóstico de cistos e granulomas periapicais. Para isso, foram selecionadas amostras obtidas no Laboratório de Patologia Cirúrgica da Faculdade de Odontologia de Pernambuco, FOP/UPE, no período de 11/2005 a 05/2008. Um total de 37 lesões, distribuídas entre cistos e granulomas periapicais, foram incluídas no estudo. Baseadas nos aspectos clínico-radiográfico e transoperatório, cirurgiões-dentistas forneceram hipóteses diagnósticas, as quais foram comparadas aos exames histopatológicos. Achados clínicos revelaram 28 casos (75,7%) de cistos, 4 casos (10,8%) de granulomas, 4 casos (10,8%) com características de ambas lesões, e 1 caso (2,7%) no qual o dentista não forneceu o diagnóstico. Entretanto, os achados histopatológicos revelaram 21 (56,8%) e 16 (43,2%) casos de cistos e granulomas, respectivamente. Os resultados mostraram uma correlação de 45,9% entre os achados para os cistos e de 8,1% para os granulomas. Diante do exposto, a discrepância observada dos achados clínicos quando comparados aos histopatológicos deve ser discutida quanto aos critérios diagnósticos que vêm sendo utilizados atualmente... (AU)

Cysts and periapical granulomas are among the most prevalent radiolucent lesions. However, there are situations where the clinical and radiographic patterns are mixed and therefore the histopathological study is necessary for definitive diagnosis. The aim of this study was to evaluate the clinical and histopathological correlation in the diagnosis of periapical cysts and granulomas. For this, samples were selected obtained from histopathological reports of Pathology Laboratory, Faculty of Dentistry of Pernambuco, FOP / UPE, during the period from 11/2005 to 05/2008. A total of 37 lesions distributed among periapical cysts and granulomas, were included in the study. Based on clinical, radiographic and intraoperative lesions, dentists provided diagnostic hypotheses, which were compared to histopathological diagnostic. Clinical findings revealed 28 cases (75.7%) of radicular cysts, 4 cases (10.8%) of granulomas alone, 4 cases (10.8%) with characteristics of both lesions, and 1 case (2.7 %) in which the dentist has not provided the diagnosis. However, the histopathological findings revealed 21 (56.8%) and 16 (43.2%) cysts and granulomas images, respectively. The results showed a 45.9% correlation between the findings for periapical cysts and 8.1% for periapical granulomas. Given the above, the discrepancy observed clinical findings compared to histopathology should be discussed as to the diagnostic criteria that have been used nowadays... (AU)

A C-Shaped Canal in a Maxillary Second Molar: Prexion 3D Cone-Beam Computed Tomography Analysis.

OBJECTIVE: The aim of this study was to present an atypical case of a C-shaped root canal that was present in the vestibular root of a permanent maxillary second molar using PreXion 3-D cone-beam computed tomography (CBCT) as a diagnostic device. MATERIALS AND METHODS: A 50-year-old female patient was referred for routine examination to a private diagnostic imaging clinic in Recife-Pernambuco. During the physical examination, the presence of an unusual C-shaped anatomy in the vestibular canal with a mesiodistal interconnection that extended from the apical to the cervical third was detected in axial slices acquired with a PreXion 3-D scanner. RESULTS: Although C-shaped root canals are most frequently observed in the mandibular second molar, this case presented a rare finding in the permanent maxillary second molar. CONCLUSIONS: PreXion 3-D CBCT has emerged as a new high-resolution imaging test technology, thus assisting with the diagnosis of anatomical variations such as C-shaped root canals. However, such imaging technology is not recommended for routine use.