In vivo evaluation of laser fluorescence performance using different cut-off limits for occlusal caries detection

The aim of this in vivo study was to evaluate the performance of laser fluorescence (LF) comparing different cut-off limits for occlusal caries detection. One hundred and thirty first permanent molars were selected. Visual examination and LF assessments were performed independently. The extent of caries was assessed after operative intervention. New cut-off limits were established and compared with those proposed by the manufacturer and by Lussi et al. (Eur J Oral Sci 109:14-19, 2001). Similar sensitivity and higher specificity was found at D(2) (considering as disease only dentin caries) when the LF cut-off limits proposed by Lussi et al. and the new one were compared. At the D(3) threshold (considering as disease only deep dentin caries), no statistically significant difference among the cut-off limits for sensitivity was found. However, the new cut-off limits showed higher specificity. The LF device provided good ability to detect dentin caries lesions. Furthermore, the new cut-off limits and the values proposed by Lussi et al. could be suggested for the in vivo detection of occlusal caries.

Reproducibility and accuracy of the ICDAS-II for occlusal caries detection

Objectives:The aim of this in vitro study was to assess the inter- and intra-examiner reproducibility and the accuracy of the International Caries Detection and Assessment System-II (ICDAS-II) in detecting occlusal caries.Methods:One hundred and sixty-three molars were independently assessed twice by two experienced dentists using the 0- to 6-graded ICDAS-II. The teeth were histologically prepared and classified using two different histological systems [Ekstrand et al. (1997) Caries Research vol. 31, pp. 224-231; Lussi et al. (1999) Caries Research vol. 33, pp. 261-266] and assessed for caries extension. Sensitivity, specificity, accuracy and area under the ROC curve (A(z)) were obtained at D(2) and D(3) thresholds. Unweighted kappa coefficient was used to assess inter- and intra-examiner reproducibility.Results:For the Ekstrand et al. histological classification the sensitivity was 0.99 and 1.00, specificity 1.00 and 0.69 and accuracy 0.99 and 0.76 at D(2) and D(3), respectively. For the Lussi et al. histological classification the sensitivity was 0.91 and 0.75, specificity 0.47 and 0.62 and accuracy 0.86 and 0.68 at D(2) and D(3), respectively. The A(z) varied from 0.54 to 0.73. The inter- and intra-examiner kappa values were 0.51 and 0.58, respectively.Conclusions:ICDAS-II presented good reproducibility and accuracy in detecting occlusal caries, especially caries lesions in the outer half of the enamel.

Molar incisor hypomineralization: prevalence, severity and clinical consequences in Brazilian children

Background.The prevalence of molar incisor hypomineralization (MIH) varies considerably around the world; however, few studies have examined MIH in South American countries.Objective.To evaluate the prevalence, severity, and clinical consequences of MIH in Brazilian children residing in rural and urban areas of the municipality of Botelhos, Minas Gerais, Brazil.Methods.Children aged 6 to 12 years (n = 918) with all four-first permanent molars erupted had these teeth evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. The examinations were conducted by two previously trained examiners, and the dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO).Results.Molar incisor hypomineralization was present in 19.8% of the 918 children, with a higher prevalence in rural areas. The majority of the defects presented were demarcated opacities without post-eruptive structural loss, which has been considered as mild defects. Children with MIH had higher DMFT values.Conclusion.Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between MIH and the presence of dental caries.

In vitro evaluation of the influence of air abrasion on detection of occlusal caries lesions in primary teeth

Purpose: The purpose of this study was to assess the influence of cleaning pits and fissures with on aluminum oxide air abrasion system on the detection of occlusal caries in primary teeth using laser fluorescence (LF) and visual examination. Methods. The sample comprised 65 pit and fissure sites on extracted primary teeth suspected to be carious. The sites were submitted to 2 visual examinations (examiner JAR) and 2 LF readings (examiner TMV). Next, the occlusal surfaces were air-abraded and re-examined thereafter using both methods. The teeth were sectioned, and the histological analysis of the sites with a stereoscopic magnifying lens at X32 magnification was used as the gold standard Results. Cohen's kappa statistic for LF and visual examination were, respectively, 0.282/0.884 before and 0.896/0.905 after air abrasion. LF showed a sensitivity of 0.28 increasing to 0.49 and 0 specificity of 0.50 increasing to 0.92. Visual examination showed sensitivity of 0.78 and specificity of 0.73. Both increased after air abrasion. Conclusion: The findings suggest that cleaning pits and fissures with aluminum oxide air abrasion increased the accuracy of LF and visual examination for detection of occlusal caries in primary teeth.

The Efficacy of Laser Fluorescence to Detect in Vitro Demineralization and Remineralization of Smooth Enamel Surfaces

Objective: The purpose of this study was to evaluate the efficacy of the laser fluorescence (LF) device in detecting in vitro demineralization and remineralization of smooth surface caries-like lesions. Background Data: The early detection of smooth surface caries-like lesions is important to provide proper management of carious lesions, and allows monitoring of them over time. Also, some authors suggest that LF could be useful in monitoring the caries pathological process. Materials and Methods: Seventy-eight blocks of bovine teeth were obtained, and then submitted to artificial caries lesion induction and to a pH-cycling process. Superficial microhardness (SMH) and laser fluorescence analysis were performed at baseline, after induction of caries-like lesions, and after the pH-cycling regimen to promote remineralization. Results: Friedman's and multiple comparison tests were performed for all variables. SMH analysis showed significant differences (p < 0.05) between baseline (286.77 +/- 1.49 Vickers hardness number [VHN] units), before (38.48 +/- 0.85 VHN), and after remineralization (131.93 +/- 2.63 VHN). Baseline values for LF were extremely low (2.71 +/- 0.05), and a statistically significant difference was observed only after remineralization (3.61 +/- 0.08), as demonstrated by the increase in LF values. Conclusion: The LF device did not show efficacy for monitoring in vitro demineralization and remineralization of smooth enamel surfaces.

Fatigue and Fluoride Corrosion on Streptococcus mutans Adherence to Titanium-Based Implant/Component Surfaces

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Analysis of mechanical behavior of implant-supported prostheses in the anterior maxilla: analysis by speckle pattern interferometry

The use of implants to rehabilitation of total edentulous, partial edentulous or single tooth is increasing, it is due to the high rate of success that this type of treatment present. The objective of this study was to analyze the mechanical behavior of different positions of two dental implants in a rehabilitation of 4 teeth in the region of maxilla anterior. The groups studied were divided according the positioning of the implants. The Group 1: Internal Hexagonal implant in position of lateral incisors and pontic in region of central incisors; Group 2: Internal Hexagonal implant in position of central incisors and cantilever of the lateral incisors and Group3 - : Internal Hexagonal implants alternate with suspended elements. The Electronic Speckle Pattern Interferometry (ESPI) technique was selected for the mechanical evaluation of the 3 groups performance. The results are shown in interferometric phase maps representing the displacement field of the prosthetic structure.

Influence of a Fluoridated Medium with Different pHs on Commercially Pure Titanium-Based Implants

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of TLR-2 in the immune response in the infection induced by fungus Sporothrix schenckii

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atividade antifúngica de óleos essenciais frente a amostras clínicas de Candida albicans isoladas de pacientes HIV positivos

Objetivou-se avaliar a atividade antifúngica dos óleos essenciais de Ocimum basilicum L. (manjericão), Cymbopogon martinii L. (palmarosa), Thymus vulgaris L. (tomilho) e Cinnamomum cassia Blume (canela da china) sobre cepas de Candida albicans isoladas de pacientes HIV positivos e cepa padrão (ATCC 76845). Quinze amostras clínicas de C. albicans (C1-C15) foram repicadas em ágar Sabouraud Dextrose, para confecção de suspensões em solução salina estéril (0,9%) contendo 1,5 x 10(6) UFC mL-1. As emulsões dos óleos essenciais foram preparadas em água destilada estéril e tween 80, com concentrações variando entre 1024 µg mL-1 e 4 µg mL-1. A ação antifúngica foi determinada por meio da Concentração Inibitória Mínima (CIM) utilizando-se a técnica da microdiluição. Foram utilizados como controles positivos a nistatina e o miconazol (50 µg mL-1). Os testes foram realizados em triplicata, sendo a CIM, a menor concentração capaz de inibir o crescimento das leveduras, observada por método visual de acordo com a turvação do meio de cultura. Para C. albicans (ATCC 76845), a CIM do óleo essencial de C. cassia foi 64 µg mL-1, enquanto para óleo de C. martinii foi 1024 µg mL-1. Para as cepas clínicas, verificou-se que a CIM de C. cassia para 80% das cepas foi 64 µg mL-1, sendo a variação dos valores da CIM entre 128 µg mL-1 e 64 µg mL-1. Observou-se que para 66,6% das amostras clínicas, a CIM de C. martinii foi 612 µg mL-1. Constatou-se que a nistatina não apresentou atividade frente às cepas clínicas (C1-C15), enquanto a atividade antifúngica do miconazol foi verificada em 100% das amostras. Não se constatou atividade antimicrobiana dos óleos essenciais de O. basilicum e T. vulgaris, nas concentrações avaliadas. Concluiu-se que os óleos essenciais de C. cassia e C. martinii, em diferentes concentrações, apresentam atividade antifúngica sobre cepas de C. albicans isoladas de pacientes HIV positivos e cepa padrão (ATCC 76845). Entretanto não foi observada inibição antimicrobiana para os óleos de O. basilicum e T. vulgaris.

Avaliações sensoriais, bioquímicas e microbiológicas do guacamole, um produto à base de abacate, sob armazenamento a frio e com adição de ácido ascórbico

The elaboration of avocado products for commercialization keeping their characteristics of fresh product has been limited. The cut avocado darkens quickly and their sensorial characteristics are modified with the storage. In the present research, the sensorial parameters, microbiological stability, and peroxidase and polyphenoloxidase activity were evaluated in guacamole added with ascorbic acid and conserved under low temperature, by using avocado variety Hass. Products were conditioned in polyethylene+nylon packages with and without vacuum application; then, they were subjected to the slow and fast freezing (-18 degrees C) and stored in freezer (-18 degrees C). Evaluations were performed at the moment of elaboration of the product (t0) and at 3, 7 and 30 days post-storage. At t30, samples were kept under refrigeration (4 +/- 1 degrees C) and evaluated at 3, 5 and 7 days. After the 30 days of storage, -18 degrees C under freezing, followed by thawing and keeping at 4 +/- 1 degrees C for 7 days, the notes for the sensorial parameters decreased. The peroxidase activity was totally inhibited in the elaborated product and the polifenol oxidase activity considerably decreased in the guacamole (20.07 mM catechol/g fresh matter) relative to those in the fruit (58.31 mM catechol/g fresh matter), however with no significant variation during storage (at -18 degrees C). The samples were microbiologically stable under the conditions of the present study. The addition of ascorbic acid contributed to the conservation of the frozen avocado product by decreasing the enzymatic activity. However, the sensorial parameters are prejudiced under thawing and storage at 4 +/- 1 degrees C.

The pulvinus endodermal cells and their relation to leaf movement in legumes of the Brazilian cerrado

Legume pulvini have a clearly delimited endodermis, whose variable content has been associated with the velocity and type of leaf movement: pulvini in leaves with fast nastic movement contain starch grains; pulvini in leaves with slow nastic movements have calcium oxalate crystals as well as starch grains in the endodermis. However, the studies carried out to date have involved few legume species. This study therefore purported to examine the consistency of this hypothesis in other legumes. Thus, the structure and content of the pulvinus endodermal cells of nine legumes of the Brazilian cerrado, with different types and velocities of leaf movement, were investigated: slow nyctinastic and heliotropic movements (Bauhinia rufa, Copaifera langsdorffii, Senna rugosa - Caesalpinioideae; Andira humilis and Dalbergia miscolobium - Faboideae; Stryphnodendron polyphyllum - Mimosoideae), slow heliotropic movement (Zornia diphylla - Faboideae), and fast seismonastic and slow nyctinastic and heliotropic movements (Mimosa rixosa and Mimosa flexuosa - Mimosoideae). Samples were prepared following standard plant anatomy and ultrastructure techniques. The endodermis of all the species contains starch grains. In the species displaying only slow movements, calcium oxalate prismatic crystals were observed in addition to starch grains, except in Zornia diphylla. in conclusion, oxalate crystals occur only in endodermal cells of pulvini that display slow movements, while starch grains are always present in pulvinus endodermal cells of plants with any kind of movement.

Pulvinus functional traits in relation to leaf movements: A light and transmission electron microscopy study of the vascular system

Previous studies on legume pulvini suggest that the vascular system plays an important role in the redistribution of ions and transmission of stimuli during leaf's movements. However, the number of anatomical and ultrastructural studies is limited to few species. The aim of this paper is to investigate the structure and cellular features of the pulvinus vascular system of nine legume species from Brazilian cerrado, looking for structural traits pointing to its participation in the leaf's movements. Samples were excised from the medial region of opened pulvinus of Bauhinia rufa, Copaifera langsdorffii, Senna rugosa (Caesalpinioideae), Andira humilis, Dalbergia miscolobium, Zornia dilphylla (Faboideae), Mimosa rixosa, Mimosa flexuosa and Stryphnodendron polyphyllum (Mimosoideae), and were prepared following light microscopy, transmission electron microscopy and histochemical standard techniques. The vascular system occupies a central position, comprises phloem and xylem and is delimited by a living sheath of septate fibers in all the species studied. This living cells sheath connects the cortex to the vascular tissues via numerous plasmodesmata. The absence of fibers and sclereids, the presence of phenolic idioblasts and the abundance and diversity of protein inclusions in the sieve tube members are remarkable features of the phloem. Pitted vessel elements, parenchyma cells with abundant cytoplasm and living fibriform elements characterize the xylem. The lack of lignified tissues and extensive symplastic continuity by plasmodesmata are remarkable features of the vascular system of pulvini of the all studied species. (c) 2007 Elsevier Ltd. All rights reserved.

Floral visitors and reproductive strategies in five melittophilous species of Bignoniaceae in Southeastern Brazil

Com objetivo de avaliar as estratégias de polinização de espécies de Bignoniaceae, foram estudados a biologia floral e os visitantes florais de cinco espécies, três arbustivas do cerrado (Arrabidaea brachypoda (DC.) Bor., Jacaranda decurrens Cham. e Jacaranda oxyphylla Cham.) e duas lianas da orla da floresta estacional semidecidual (Arrabidaea samydoides (Cham.) Sandw. e Arrabidaea triplinervia H. Baill.), na região de Botucatu (22º52'20 S e 48(0)26'37 W), estado de São Paulo, sudeste do Brasil. Os períodos de florescimento, principalmente entre espécies do mesmo habitat, apresentaram sobreposição parcial. Observou-se que as cinco espécies são alogâmicas funcionais, melitófilas, nototríbicas, polinizadas principalmente por abelhas grandes de língua comprida. Algumas abelhas coletoras de pólen de tamanho médio e pequeno atuaram como polinizadoras ocasionais, enquanto outros visitantes foram pilhadores. Cada uma das Bignoniaceae apresentou um conjunto particular de polinizadores havendo apenas duas espécies comuns a mais de uma delas. Não houve partilha de polinizadores mesmo entre bignoniáceas que, no mesmo habitat, apresentaram períodos de florescimento simultâneo.

Hymenaea stigonocarpa Mart. ex Hayne: A Brazilian medicinal plant with gastric and duodenal anti-ulcer and antidiarrheal effects in experimental rodent models

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)