Influence of different catilever extensions and glass or polyamaramid reinforcement fibers on fracture strength of implant-supported temporary

In long-term oral rehabilitation treatments, resistance of provisional crowns is a very important factor, especially in cases of an extensive edentulous distal space. The aim of this laboratorial study was to evaluate an acrylic resin cantilever-type prosthesis regarding the flexural strength of its in-balance portion as a function of its extension variation and reinforcement by two types of fibers (glass and polyaramid), considering that literature is not conclusive on this subject. Each specimen was composed by 3 total crowns at its mesial portion, each one attached to an implant component (abutment), while the distal portion (cantilever) had two crowns. Each specimen was constructed by injecting acrylic resin into a two-part silicone matrix placed on a metallic base. In each specimen, the crowns were fabricated with either acrylic resin (control group) or acrylic resin reinforced by glass (Fibrante, Angelus) or polyaramide (Kevlar 49, Du Pont) fibers. Compression load was applied on the cantilever, in a point located 7, 14 or 21 mm from the distal surface of the nearest crown with abutment, to simulate different extensions. The specimen was fixed on the metallic base and the force was applied until fracture in a universal test machine. Each one of the 9 sub-groups was composed by 10 specimens. Flexural strength means (in kgf) for the distances of 7, 14 and 21 mm were, respectively, 28.07, 8.27 and 6.39 for control group, 31.89, 9.18 and 5.16 for Kevlar 49 and 30.90, 9.31 and 6.86 for Fibrante. Data analysis ANOVA showed statistically significant difference (p<0.05) only regarding cantilever extension. Tukey's test detected significantly higher flexural strength for the 7 mm-distance, followed by 14 and 21 mm. Fracture was complete only on specimens of non-reinforced groups.

Caracterização do jogo simbólico em deficientes auditivos: estudo de casos e controles

TEMA: crianças deficientes auditivas não adquirem linguagem no mesmo período e velocidade de uma criança normo-ouvinte, pois o aprendizado da linguagem oral é um evento essencialmente auditivo. O desenvolvimento da criança consiste na aquisição progressiva de habilidades motoras e psicocognitivas, e a entrada no mundo simbólico é fator preponderante para que a criança possa atingir os níveis de maior complexidade no domínio da linguagem. OBJETIVO: relacionar o jogo simbólico e aspectos do desenvolvimento infantil em crianças deficientes auditivas com seus pares ouvintes. MÉTODO: 32 crianças, de ambos os sexos, de 2 a 6 anos de idade, pareadas por idade, foram submetidas à Avaliação da Maturidade Simbólica e ao Teste de Triagem do Desenvolvimento de Denver II, sendo 16 deficientes auditivas neurossensorial de grau moderado a profundo (grupo pesquisa - GP) e 16 normo-ouvintes (grupo controle - GC). RESULTADOS: observou-se simbolismo na brincadeira de 81,25% do GP, enquanto que no GC isto ocorreu em 87,5%. No Teste de Denver II 100% do GP foi classificado como risco, e o GC apresentou 94% de crianças normais e 6% de risco (p < 0,001). CONCLUSÃO: observou-se desempenho semelhante nos dois grupos quanto ao jogo simbólico. Entretanto, numa análise qualitativa, o GP apresentou brincadeiras menos complexas que o GC. Observou-se que o GP apresentou desempenho no jogo simbólico compatível ao seu desempenho nos aspectos pessoal-social, motor fino-adaptativo e motor grosseiro do Teste de Denver II.

Determination of the maximum inhibitory dilution of cetylpyridinium chloride-based mouthwashes against staphylococcus aureus: an in vitro study

The aim of this in vitro study was to determine the maximum inhibitory dilution (MID) of four cetylpyridinium chloride (CPC)-based mouthwashes: CPC+Propolis, CPC+Malva, CPC+Eucaliptol+Juá+Romã+Propolis (Natural Honey®) and CPC (Cepacol®), against 28 Staphylococcus aureus field strains, using the agar dilution method. Decimal dilutions ranging from 1/10 to 1/655,360 were prepared and added to Mueller Hinton Agar. Strains were inoculated using Steers multipoint inoculator. The inocula were seeded onto the surface of the culture medium in Petri dishes containing different dilutions of the mouthwashes. The dishes were incubated at 37ºC for 24 h. For readings, the MID was considered as the maximum dilution of mouthwash still capable of inhibiting microbial growth. The obtained data showed that CPC+Propolis had antimicrobial activity against 27 strains at 1/320 dilution and against all 28 strains at 1/160 dilution, CPC+Malva inhibited the growth of all 28 strains at 1/320 dilution, CPC+Eucaliptol+Juá+Romã+Propolis inhibited the growth of 2 strains at 1/640 dilution and all 28 strains at 1/320 dilution, and Cepacol® showed antimicrobial activity against 3 strains at 1/320 dilution and against all 28 strains at 1/160 dilution. Data were submitted to Kruskal-Wallis test, showing that the MID of Cepacol® was lower than that determined for the other products (p<0.05). In conclusion, CPC-mouthwashes showed antimicrobial activity against S. aureus and the addition of other substances to CPC improved its antimicrobial effect.

Bleaching of melanin in the epidermis of South American fur seal and its application on enzyme immunohistochemistry

The South American fur seal (Arctocephalus australis) is an amphibious marine mammal distributed along the Atlantic and Pacific coasts of South America. The species is well adjusted to different habitats due to the morphology of its fin-like members and due to some adaptations in their integumentary system. Immunohistochemical studies are very important to evaluate the mechanisms of skin adaptation due the differential expression of the antigens present in the tissue depending of the region of the body surface. However, its strongly pigmented (melanin) epidermis prevents the visualization of the immuno-histochemical chromogens markers. In this study a melanin bleaching method was developed aimed to allow the visualization of the chromogens without interfering in the antigen-antibody affinity for immunohistochemistry. The analysis of PCNA (proliferating cell nuclear antigen) index in the epidermis of A. australis by immunohistochemistry with diaminobenzidine (DAB) as chromogen was used to test the method. The bleaching of the melanin allowed to obtain the cell proliferation index in epidermis and to avoid false positive results without affecting the immunohistochemical results.

Eficácia da laserterapia nas disfunções têmporo-mandibulares: estudo controle

A disfunção têmporo-mandibular é caracterizada pela presença de sintomatologia dolorosa articular/muscular na região da face. A principal justificativa do uso do laser da laserterapia na disfunção é seu efeito analgésico, fato observado na maioria dos estudos encontrados na literatura. OBJETIVO: Foi avaliar a eficácia da laserterapia no tratamento das disfunções têmporo-mandibulares. MATERIAL E MÉTODO: 50 voluntários com disfunção têmporo-mandibular foram divididos em dois grupos (controle e experimental) tiveram as amplitudes dos movimentos de abertura bucal, lateralidade direita e esquerda registrados, antes e após aplicação do laser. Foi registrada, também, a nota de dor do indivíduo através da escala analógica visual de dor e, através do exame físico, os pontos álgicos. Utilizou-se o laser de AsGaAl com potência de 40mW, com 80J/cm², por 16 segundos, em quatro pontos selecionados por apenas uma sessão com reavaliação após uma semana. Desenho Científico Utilizado: Clínico. RESULTADOS: Notou-se que a laserterapia promoveu aumento da média de amplitude dos movimentos mandibulares (p=0,0317) e houve redução significativa (43,6%) da intensidade de dor dos pacientes medida através da escala analógica visual de dor. CONCLUSÕES: A laserterapia promove redução da sintomatologia dolorosa do paciente após a aplicação por ação analgésica e/ou por um efeito placebo.

Intrapupal temperature variation during Er,Cr: YSGG enamel irradiation on carries prevention

Studies have shown the cariostatic effect of Er,Cr:YSGG (2.78 mm) laser irradiation on human enamel and have suggested its use on caries prevention. However there are still no reports on the intrapulpal temperature increase during enamel irradiation using parameters for caries prevention. The aim of this in vitro study was to evaluate the temperature variation in the pulp chamber during human enamel irradiation with Er,Cr:YSGG laser at different energy densities. Fifteen enamel blocks obtained from third molars (3 x 3 x 3 mm) were randomly assigned to 3 groups (n=5): G1 - Er,Cr:YSGG laser 0.25 W, 20 Hz, 2.84 J/cm², G2 - Er,Cr:YSGG laser 0.50 W, 20 Hz, 5.68 J/cm², G3 - Er,Cr:YSGG laser 0.75 W, 20 Hz, 8.52 J/cm². During enamel irradiation, two thermocouples were fixed in the inner surface of the specimens and a thermal conducting paste was used. One-way ANOVA did not show statistically significant difference among the experimental groups (a=0.05). There was intrapulpal temperature variation <0.1ºC for all irradiation parameters. In conclusion, under the tested conditions, the use of Er,Cr:YSGG laser with parameters set for caries prevention lead to an acceptable temperature increase in the pulp chamber.

Fine needle aspiration biopsy in the oral cavity and head and neck region

The objective of the current study was to evaluate the sensitivity, specificity and accuracy of fine needle aspiration biopsy (FNAB) of submucous nodules from the oral cavity and head and neck region as an auxiliary diagnostic tool. Fifty patients with nodule lesions in the oral cavity and the head and neck region were selected. All of them were submitted to FNAB and to either incisional or excisional biopsy. The diagnoses from the FNABs were compared with the biopsy diagnosis as the gold standard. All the cases of FNAB were analyzed by a single oral pathologist prior to the biopsy diagnosis. The results showed that the sensitivity of FNAB was 75%, its specificity was 96% and its accuracy was 58.8%. The false positive and false negative rates were 6.7% and 13.3%, respectively. The positive predictive value was 86% and the negative predictive value was 93%. The inconclusive rate was 16/50. FNAB displayed a high success rate for identifying both malignant and benign lesions, but a low accuracy for making a final diagnosis.

Influence of bioactive materials used on the dentin surface whitened with carbamide peroxide 16%

This study investigated the influence of bioactive materials on the dentin surface whitened. MATERIAL AND METHODS: Three bovine teeth were shaped into three dentin wafers. Each wafer was then sectioned, into six dentin slices. One slice from each tooth was distributed into one of 6 groups: 1.CG = control group (distilled water); 2.WT = whitening treatment; 3.WT + MI Paste Plus, applied once a day; 4.WT + Relief ACP30, applied once a day for 30 mintes; 5.WT + Relief ACP60, applied once a day for 60 minutes; 6.WT + Biosilicate®, applied once a week. All groups were treated over 14 days. RESULTS: CG presented all dentinal tubules occluded by smear layer; WT group was observed all dentinal tubules opened. In the groups 3, 4 and 6, tubules were occluded. Group 5, dentinal tubules were completely occluded by mineral deposits. CONCLUSION: The use of bioactive materials immediately after whitening treatment can reduce or even avoid the demineralization effect of whitening and avoid exposing dentinal tubules.

Rhinometric evaluation of nasal cavity geometry and its relation to the upper arch transverse distance

The objective of this study was to evaluate children's respiratory patterns in the mixed dentition, by means of acoustic rhinometry, and its relation to the upper arch width development. Fifty patients were examined, 25 females and 25 males with mean age of eight years and seven months. All of them were submitted to acoustic rhinometry and upper and lower arch impressions to obtain plaster models. The upper arch analysis was accomplished by measuring the interdental transverse distance of the upper teeth, deciduous canines (measurement 1), deciduous first molars (measurement 2), deciduous second molars (measurement 3) and the first molars (measurement 4). The results showed that an increased left nasal cavity area in females means an increased interdental distance of the deciduous first molars and deciduous second molars and an increased interdental distance of the deciduous canines, deciduous first and second molars in males. It was concluded that there is a correlation between the nasal cavity area and the upper arch transverse distance in the anterior and mid maxillary regions for both genders.

Dor nos dentes e gengivas e fatores associados em adolescentes brasileiros: análise do inquérito nacional de saúde bucal SB-Brasil 2002-2003

Estimou-se a prevalência de dor nos dentes e gengivas e fatores associados em adolescentes brasileiros de 15 a 19 anos de idade. Foram utilizadas informações de 16.126 adolescentes participantes do levantamento epidemiológico nacional de saúde bucal - SB Brasil 2002-2003. O desfecho foi o relato de dor nos dentes e gengivas nos últimos seis meses. As variáveis exploratórias foram: renda per capita, escolaridade, condição de estudo, sexo, cor da pele, idade, localização geográfica da residência, tipo de serviço odontológico utilizado pela última vez, tempo decorrido da última consulta odontológica, índice CPO-D e seus componentes, cálculo dentário e o índice de estética dental. Foram realizadas análises brutas e múltiplas utilizando a regressão de Poisson. A prevalência da dor de dentes e gengivas foi de 35,6% (IC95%: 34,8-36,4). A prevalência de dor foi maior nas meninas, naqueles pertencentes a famílias com baixa renda per capita, nos não estudantes e estudantes de escola pública e naqueles com baixa escolaridade para a idade. Indivíduos que apresentaram altos níveis de cárie e cálculo dentário também apresentaram maiores prevalências do desfecho. A dor nos dentes e gengivas em adolescentes pode ser considerada um problema relevante em saúde pública sugerindo a necessidade de ações preventivas e de promoção da saúde.

A method to determine volatile contaminants in polyethylene terephthalate (PET) packages by HDC-GC-FID and its application to post-consumer materials

A simple and low cost method to determine volatile contaminants in post-consumer recycled PET flakes was developed and validated by Headspace Dynamic Concentration and Gas Chromatography-Flame Ionization Detection (HDC-GC-FID). The analytical parameters evaluated by using surrogates include: correlation coefficient, detection limit, quantification limit, accuracy, intra-assay precision, and inter-assay precision. In order to compare the efficiency of the proposed method to recognized automated techniques, post-consumer PET packaging samples collected in Brazil were used. GC-MS was used to confirm the identity of the substances identified in the PET packaging. Some of the identified contaminants were estimated in the post-consumer material at concentrations higher than 220 ng.g-1. The findings in this work corroborate data available in the scientific literature pointing out the suitability of the proposed analytical method.

Sensitivity to halothane and its relationship to the development of PSE (Pale, Soft, Exudative) meat in female lineage broilers

This work aimed to evaluate female lineage broilers for halothane sensitivity and for their susceptibility to the subsequent development of PSE meat. The halothane test was carried out in an anesthetic chamber with 3.0% halothane. The unconscious birds were examined for leg muscle rigidity. If one or both legs became extended and rigid, the birds were classified as halothane sensitive (HAL+), while unresponsive birds were classified as halothane negative (HAL-). The results showed that of 298 birds aged 42 days old, 95.6% were HAL- and 4.4% were HAL+. A sample of pectoralis major muscle was collected from HAL- (n=105) and HAL+ (n=13) birds. The pH and breast fillet color were determined at 4ºC, 24 hours post-mortem. Interestingly, only 2.5% of HAL+ birds displayed PSE meat characteristics compared to 12.7% of HAL- individuals. The halothane test demonstrated that female lineage broilers displayed very little sensitivity towards halothane, indicating that the development of PSE meat is related to other environmental factors.

Levels of yeast and its by-products on pacu juveniles feeding

This study was conducted to evaluate the inclusion of two levels (2.5 e 5.0%) of dried yeast (Saccharomyces cerevisiae) and its by-products, disrupted yeast cells and yeast cell wall in diets for juveniles of pacu (Piaractus mesopotamicus). Production performance, body and plasmatic composition indexes were evaluated. Seven isoproteic (26% digestible protein) and isoenergetic (3.100 kcal digestible energy) diets were formulated containing increased levels of each ingredient. The diets were supplied for 86 days, "ad libitum". Yeast and by-products increase feed efficiency and protein use, when compared to the control diet. Carcass composition and plasmatic (glucose, cortisol, uric acid, urea and plasmatic protein) levels are not affected by the test ingredient supplementation.

Phylogenetic analyses of Cladophora vagabunda (L.) C. Hoek (Cladophorales, Chlorophyta) from Brazil based on SSU rDNA sequences

The complete SSU rDNA was sequenced for 10 individuals of Cladophora vagabunda collected along the coast of Brazil. For C. rupestris (L.) Kütz. a partial SSU rDNA sequence (1634 bp) was obtained. Phylogenetic trees indicate that Cladophora is paraphyletic, but the section Glomeratae sensu lato including C. vagabunda from Brazil, Japan and France, C. albida (Nees) Kütz., C. sericea (Hudson) Kütz., and C. glomerata (L.) Kütz. is monophyletic. Within this group C. vagabunda is paraphyletic. The sequence identity for the SSU rDNA varied from 98.9% to 100% for the Brazilian C. vagabunda, and from 98.3% to 99.7% comparing the Brazilian individuals to the ones from France and Japan. Sequence identity of the Brazilian C. vagabunda to C. albida and C. sericea vary from 98.0% to 98.6%. The SSU rDNA phylogeny support partially the morphological characteristics presented by Brazilian populations of C. vagabunda. On the other hand, C. rupestris from Brazil does not group with C. rupestris from France, both sequences presenting only 96.9% of identity. The inclusion of sequences of individuals from Brazil reinforces the need of taxonomical revision for the genus Cladophora and for the complex C. vagabunda.

Revisão taxonômica de Croton sect. Lamprocroton (Müll. Arg.) Pax (Euphorbiaceae s.s.)

Croton is the second bigger and more diverse genus in the family Euphorbiaceae, with about 1,200 species distributed in 40 sections, occurring in all tropical areas, most of them in Americas. In South America, Brazil is the country in which a larger number of taxa are found, ca. 356. According to recent classification, the genus belongs to the tribe Crotoneae, and despite the wide and morphological diversity, it would be a monophyletic taxon. However, a phylogenetic analysis using markers of ITS region from nuclear ribosomal DNA, and of trnL-F from plastidial DNA, showed that Croton, like traditionally circumscribed, is not a monophyletic taxon. A taxonomic revision of Croton section Lamprocroton (Müll. Arg.) Pax is presented here. It is a Neotropical group with most of its species occurring from Southeast and South Brazil to southern South America (Uruguay and Argentina). Morphologically, the members of Lamprocroton are characterized as monoecious or dioecious shrubs or subshrubs, with a lepidote indumentum at least in part of foliage, entire leaves with no glands. The staminate flowers have 9 to 16 stamens and the pistillate flowers may have equal or unequal sepals, reduced to absent petals, and styles once or twice bifid. Overall, are recognized 26 species in the group, three of them new to the science. Identification key, morphological descriptions, illustrations, phenological period, as well as data on geographic distribution and general comments of each species are presented. Four taxa were excluded from C. sect. Lamprocroton because they do not show the morphological features that are diagnostics of the section. Four species that are poorly known were not included in the taxonomic treatment.