Knowledge, attitudes and practices of undergraduate students and dentists about dental prenatal care.

INTRODUCTION: Prenatal care is a fundamental moment for health promotion to be carried out, since at that moment women are more receptive to new knowledge, with the aim of providing better healthcare for the baby. This study aimed to evaluate the knowledge, attitudes and practices of undergraduate students and professionals, both from the public and from private sectors in Brazil, regarding dental prenatal care. MATERIALS AND METHODS: This study corresponded to an online questionnaire survey, via Google Forms, consisting of 17 general questions for undergraduates (n = 103) and 16 for professionals (n = 227) for demographic and school mapping, and 18 specific questions about the importance and protocol of dental prenatal care. T-test, Mann-Whitney U-test and multiple linear regression were adopted (p < .05). RESULTS: The average total score of the questionnaire for students and professionals was 12.40 and 15.65, respectively (p < .0001), indicating moderate knowledge. Professionals showed a higher prevalence of moderate (77%) and high (2%) knowledge of the subject when compared to undergraduate students (51% and 0% respectively). The graduation period in which the students were enrolled was a predictor of the total score of the questionnaire [F (1, 101) = 21.21; p < .0001; R2  = .165]. The female gender and the lower weekly workload were the main predictors of the total score of the questionnaire for professionals [F (3, 223) = 6.74; p < .0001; R2  = .083]. CONCLUSIONS: Although professionals have greater knowledge about dental prenatal care than students, there are still deficiencies in the knowledge and practices of them in respect of dental management during pregnancy. Higher education institutions need to change the teaching-learning plan regarding the holistic dental approach for women during pregnancy.

Botulinum Toxin A in the Management of a Gummy Smile: A Clinical Controlled Preliminary Study.

BACKGROUND: Botulinum toxin type A (BTX-A) is recent technique for the treatment of gummy smile. OBJECTIVES: The aim of this randomized controlled preliminary clinical trial was to evaluate the effects of BTX-A on excessive gingiva display (EGD) reduction, muscle activity, and patient satisfaction at 2, 8, 12, 16, 21, and 25 weeks. METHODS: Group 1 (G1) received 4 points of BTX-A application (2 U/point) for relaxation of the levator labii superioris alaeque nasi and levator labii superioris muscles; Group 2 (G2) received 2 points of BTX-A (2 U/point) for relaxation of only the levator labii superioris alaeque nasi muscle. RESULTS: A high dropout of patients from follow-up sessions occurred. Therefore, because of this data limitation, the results were considered a preliminary outcome. At 2 weeks, there was a significant difference between baseline regarding the reduction of EGD in G1 and G2, reduction in muscle activity in G1, and increased satisfaction in G1 and G2. At 2 weeks, there was no difference between the 2 groups. Statistically significant EGD reduction was maintained until 16 weeks in G2 and 25 weeks in G1. After 14 days there was a gradual recovery of muscle activity in both groups until recovery of baseline values by 25 weeks. Patients' satisfaction with treatment lasted 21 weeks in G1 and 16 weeks in G2. CONCLUSIONS: Increasing the number of BTX-A injection points resulted in a prolonged effect regarding EGD reduction and patient satisfaction but did not increase the intensity of the outcome. However, due to the high dropout of patients, this is a preliminary conclusion and further studies are necessary to confirm these results.

Ovine gammaherpesvirus-2 infection associated with chronic interstitial pneumonia in a sheep.

Sheep Associated-Malignant Catarrhal Fever (SA-MCF) is severe, frequently lethal, lymphoproliferative disease predominantly of ruminants, that is caused by ovine gammaherpesvirus-2 (OvHV-2), a member of the MCF virus (MCFV) complex. However, SA-MCF in sheep is a rare entity with few demonstrations of natural diseases worldwide. This report documents the clinical, radiographical, pathological, immunohistochemical, and molecular findings of SA-MCF in a sheep. A 4-year-old, female, mixed-breed sheep with progressive emaciation for at least one month was humanely euthanized due to poor prognosis. Clinically, the animal had tachypnea, ruminal hypomotility, productive coughing with bilateral muffling sounds during pulmonary auscultation. Radiographical evaluation revealed alveolar opacity of the cranioventral pulmonary region. Grossly, there were distinct rib impressions on the pleural surface of the lungs, suggestive of interstitial pneumonia. Histopathologic evaluation of the lungs revealed several disease patterns including 1) chronic interstitial pneumonia with vasculitis and proliferating vascular lesions, and thrombosis; 2) pulmonary abscesses associated with embolic dissemination of Corynebacterium pseudotuberculosis from superficial lymph node due to caseous lymphadenitis, CLA; 3) granulomatous pneumonia associated with pulmonary nematodes; and 4) chronic pleuritis, probably due to caseous lymphadenitis. Additional significant histologic findings included widespread lymphocytic vasculitis and proliferating vascular lesions in multiple tissues, atrophic enteritis, segmental degeneration of myocardial fibers with lymphocytic pericarditis, lymphocytic interstitial nephritis, and non-suppurative encephalitis. An immunohistochemistry (IHC) assay, based on the monoclonal antibody 15A (MAb-15A), that is specific to all MCFV known to cause MCF, revealed positive, intracytoplasmic, intralesional immunoreactivity, predominantly within bronchial and bronchiolar epithelial cells of the lungs and cryptal epithelial cells of the small intestine, followed by the renal tubular epithelium, cardiomyocytes, and with patchy immunolabelling within neurons of the cerebral cortex. Molecular testing done to detect a wide range of bacterial and viral agents of ruminant diseases, only amplified OvHV-2 DNA from fresh tissue fragments of the lungs, kidney, liver, spleen, and cerebrum. Direct sequencing confirmed that the PCR amplicon derived from the pulmonary fragments had 99.2-99.7% nucleotide sequence identity with OvHV-2 reference strains and strains of OvHV-2 from Brazil. The clinical, radiographical, gross, histopathologic, IHC, and molecular findings in the lungs are consistent with chronic interstitial pneumonia associated with infection by OvHV-2. Furthermore, the non-detection of other viral agents associated with pulmonary diseases in ruminants suggest that OvHV-2 was directly associated with the development of chronic pneumonia in this sheep. Additionally, the dental alterations, CLA, and the pulmonary nematode may have contributed towards the reduced immunological statue of the animal and facilitated the occurrence of SA-MCF. These findings may indicate that OvHV-2 may be a major participant in the pathogenesis of pulmonary disease of sheep under special conditions. Moreover, the proliferating vascular lesions identified in multiple tissues are additional evidence of chronic manifestations of OvHV-2 infections as described in chronic SA-MCF of cattle, while the widespread vasculitis is consistent with SA-MCF. Additionally, the IHC findings using the MAb-15A confirmed that this diagnostic approach is efficient to identify intralesional antigens of OvHV-2.

Effect of Air-Particle-Abrasion Protocols on Surface Roughness and Early Biofilm Formation of Zirconia.

PURPOSE: The air-particle-abrasion on zirconia in the gingival area of connectors and pontics in fixed partial dentures appears to increase fracture resistance. This study evaluated 'in situ' biofilm formation on the zirconia surface after different air-particle-abrasion protocols. MATERIALS AND METHODS: Ninety sintered blocks (5 × 5 × 2 mm) of yttrium partially stabilised zirconia (Y-TZP) were obtained and randomised among nine groups according to the factors 'type of particle' (Alumina 50 and 110 µm; Cojet and Rocatec) and 'pressure' (2.5 and 3.5 bar) used for sandblasting for 10 s. The surface roughness (Ra/Rz) was measured before and after sandblasting. For the in-situ analyses, custom-made removable intraoral devices n = 10 with one sample of each group attached to the buccal area were used by volunteers for 8 h at night. The specimens were analysed under confocal microscopy to quantify both biovolume and thickness of the initial biofilm formed. One-way analysis of variance (ANOVA) and Dunnett's tests were performed (5%). RESULTS: The roughness values ranged from 0.05 to 0.39 µm for Ra and from 0.35 to 2.11 µm for Rz, p = 0.00. Mean biofilm thickness ranged from 0.06 and 0.54 µm (p = 0.005), while the biovolume values were between 0.02 and 0.61 µm3/µm2 (p = 0.002). Values statistically significant for biofilm thickness and biovolume were found in groups sandblasted with Rocatec using 3.5 bar. CONCLUSION: In order to increase the fracture resistance of zirconia fixed partial dentures (FPDs), the air particle abrasion of zirconia with SiO2 (110 µm/3.5 bar), in the gingival area of connectors and pontics, should be avoided.

A comparison of the film thickness of two adhesive luting agents and the effect of thermocycling on their microTBs to feldspathic ceramic.

The aim of the present study was to evaluate the effect of thermocycling (TC) on the microtensile bond strength (microTBS) of two luting agents to feldspathic ceramic and to measure their film thickness (FT). For the microTBS test, sixteen blocks (6.4 x 6.4 x 4.8 mm) were fabricated using a feldspathic ceramic, etched with 10% hydrofluoric acid, rinsed and treated with the silane agent. The ceramic blocks were divided into two groups (n= 8): Gr1: dual-cured resin cement and Gr2: flowable resin. The luting agents were applied on the treated surfaces. Microsticks (1 +/-0. 1mm2) were prepared and stored under two conditions: dry, specimens immediately submitted to the microTBS test, and TC (6,000 cycles; 5 degrees C-55 degrees C). The microTBS was evaluated using a universal testing machine (1 mm/min). The microTBS data (MPa) were submitted to two-way ANOVA and Tukey' test (5%). For the FT test (ISO 4049), 0.05 ml of each luting agent (n=8) was pressed between two Mylar-covered glass plates (150 N) for 180 seconds and light polymerized. FT was measured using a digital paquimeter (Model 727-2001). The data (mm) were submitted to one-way ANOVA. The luting cement did not influence the microTBS results (p= 0.4467). Higher microtensile bond values were found after TC (20.5 +/- 8.6 MPa) compared to the dry condition (13.9 +/- 4. 7MPa), for both luting agents. The luting agents presented similar film thicknesses: Gr1- 0.052 +/- 0.016 mm; Gr2-0.041 +/- 0.003 mm. The luting agents presented similar film thickness and microTBS values, in dry and TC conditions and TC increased the bond strength regardless of the luting agent.

Prostaglandin E2 Induces Expression of Mineralization Genes by Undifferentiated Dental Pulp Cells.

Prostaglandin E2 (PGE2) is a lipid mediator usually released during inflammation. This study aimed to investigate the potential of soluble or microsphere-loaded PGE2 on inducing differentiation of dental pulp stem cells. PGE2-loaded microspheres (MS) were prepared using an oil-in-water emulsion solvent extraction-evaporation process and were characterized. Mouse dental pulp stem cells (OD-21) were stimulated with soluble or PGE2-loaded MS (0.01 and 0.1 µM). Cell viability was determined by MTT colorimetric assay. Ibsp, Bmp2 and Runx2 expression was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) after 3, 6, and 24 h. The results showed that the soluble PGE2 reduced dental pulp stem cells viability after 24 h of stimulation whereas PGE2-loaded MS did not. Soluble PGE2 up-regulated Ibsp and Bmp2 at 3 h, differently from PGE2-loaded MS. On the other hand, PGE2-MS induced Bmp2 and Runx2 at 6 h and Ibsp at 24 h. In conclusion, our in vitro results show that PGE2, soluble or loaded in MS are not cytotoxic and modulateIbsp,Bmp2, andRunx2gene expression in cultured OD-21 cells.

Lipoxin A4 encapsulated in PLGA microparticles accelerates wound healing of skin ulcers.

Lipoxin A4 (LXA4) is involved in the resolution of inflammation and wound healing; however, it is extremely unstable. Thus, to preserve its biological activities and confer stability, we encapsulated LXA4 in poly-lactic-co-glycolic acid (PLGA) microparticles (LXA4-MS) and assessed its application in treating dorsal rat skin lesions. Ulcers were sealed with fibrin adhesive and treated with either LXA4-MS, unloaded microparticles (Un-MS), soluble LXA4, or PBS/glue (vehicle). All groups were compared at 0, 2, 7, and 14 days post-lesions. Our results revealed that LXA4-MS accelerated wound healing from day 7 and reduced initial ulcer diameters by 80%. Soluble LXA4, Un-MS, or PBS closed wounds by 60%, 45%, and 39%, respectively. LXA4-MS reduced IL-1ß and TNF-α, but increased TGF-ß, collagen deposition, and the number of blood vessels. Compared to other treatments, LXA4-MS reduced inflammatory cell numbers, myeloperoxidase (MPO) concentration, and metalloproteinase-8 (MMP8) mRNA in scar tissue, indicating decreased neutrophil chemotaxis. In addition, LXA4-MS treatment increased macrophages and IL-4, suggesting a positive impact on wound healing. Finally, we demonstrated that WRW4, a selective LXA4 receptor (ALX) antagonist, reversed healing by 50%, indicating that LXA4 must interact with ALX to induce wound healing. Our results show that LXA4-MS could be used as a pharmaceutical formulation for the treatment of skin ulcers.

Processamento de produtos odontológicos em unidades básicas de saúde na cidade de Porto Velho, Rondônia / Processing of dental products in basic health units of Porto Velho, Rondônia

Avaliar o processamento de produtos odontológicos em unidades básicas de saúde na cidade de Porto Velho, capital de Rondônia. Estudo transversal conduzido em 13 unidades com coleta em três etapas: preenchimento de questionário, observação não participante e leitura de registros. A conformidade no processamento dos produtos foi avaliada de acordo com as recomendações e normativas vigentes no Brasil. Pouco mais da metade das unidades apresenta sala de expurgo exclusiva (53,8%) e havia inconformidades relacionadas à iluminação (69,3%), água potável (100,0%) e falta de escovas adequadas (46,2%). Todas as unidades ofereciam equipamento de proteção individual. Apenas 18,6% utilizavam detergentes adequados ou sabão desincrustante e 100,0% dos produtos eram lavados manualmente. As principais inconformidades foram o uso de material abrasivo (46,2%), não utilização de óculos ou máscaras (100,0%), inspeção incorreta após a lavagem (100,0%), preparo inadequado de soluções de desinfecção química (77,0%) e 84,6% não realizavam o enxágue adequado. O processamento de produtos odontológicos na atenção básica de saúde na cidade de Porto Velho apresenta fragilidades que podem levar a infecções relacionadas à assistência à saúde.

To evaluate the processing of dental products in basic health units in the capital of Rondônia. Cross-sectional study conducted in 13 units with collection in three stages: filling out a questionnaire, non-participant observation and reading of records. Compliance in the processing of products was evaluated in accordance with the recommendations and regulations in force in Brazil. Just over half of the units have an exclusive purge room (53.8%) and there were nonconformities related to lighting (69.3%), potable water (100%) and lack of adequate brushes (46.2%). All units offered personal protective equipment. Only 18.6% used adequate detergents or descaling soap and 100.0% of the products were washed manually. The main nonconformities were the use of abrasive material (46.2%), non-use of glasses or masks (100.0%), non-correct inspection after washing (100.0%), inadequate preparation of chemical disinfection solutions (77.0%) and 84.6% did not rinse with abundant water. The processing of dental products in in primary care in Porto Velho has weaknesses that can lead to infections related to health care.

Microspheres prepared with different co-polymers of poly(lactic-glycolic acid) (PLGA) or with chitosan cause distinct effects on macrophages.

Microencapsulation of bioactive molecules for modulating the immune response during infectious or inflammatory events is a promising approach, since microspheres (MS) protect these labile biomolecules against fast degradation, prolong the delivery over longer periods of time and, in many situations, target their delivery to site of action, avoiding toxic side effects. Little is known, however, about the influence of different polymers used to prepare MS on macrophages. This paper aims to address this issue by evaluating in vitro cytotoxicity, phagocytosis profile and cytokines release from alveolar macrophages (J-774.1) treated with MS prepared with chitosan, and four different co-polymers of PLGA [poly (lactic-co-glycolic acid)]. The five MS prepared presented similar diameter and zeta potential each other. Chitosan-MS showed to be cytotoxic to J-774.1 cells, in contrast to PLGA-MS, which were all innocuous to this cell linage. PLGA 5000-MS was more efficiently phagocytized by macrophages compared to the other MS tested. PLGA 5000-MS and 5002-MS induced significant production of TNF-α, while 5000-MS, 5004-MS and 7502-MS decreased spontaneous IL-6 release. Nevertheless, only PLGA 5002-MS induced significant NFkB/SEAP activation. These findings together show that MS prepared with distinct PLGA co-polymers are differently recognized by macrophages, depending on proportion of lactic and glycolic acid in polymeric chain, and on molecular weight of the co-polymer used. Selection of the most adequate polymer to prepare a microparticulate drug delivery system to modulate immunologic system may take into account, therefore, which kind of immunomodulatory response is more adequate for the required treatment.

Prostaglandin D2-loaded microspheres effectively activate macrophage effector functions.

Biodegradable lactic-co-glycolic acid (PLGA) microspheres (MS) improve the stability of biomolecules stability and allow enable their sustained release. Lipid mediators represent a strategy for improving host defense; however, most of these mediators, such as prostaglandin D2 (PGD2), have low water solubility and are unstable. The present study aimed to develop and characterize MS loaded with PGD2 (PGD2-MS) to obtain an innovative tool to activate macrophages. PGD2-MS were prepared using an oil-in-water emulsion solvent extraction-evaporation process, and the size, zeta potential, surface morphology and encapsulation efficiency were determined. It was also evaluated in vitro the phagocytic index, NF-κB activation, as well as nitric oxide and cytokine production by alveolar macrophages (AMs) in response to PGD2-MS. PGD2-MS were spherical with a diameter of 5.0±3.3 µm and regular surface, zeta potential of -13.4±5.6 mV, and 36% of encapsulation efficiency, with 16-26% release of entrapped PGD2 at 4 and 48 h, respectively. PGD2-MS were more efficiently internalized by AMs than unloaded-MS, and activated NF-κB more than free PGD2. Moreover, PGD2-MS stimulated the production of nitric oxide, TNF-α, IL-1ß, and TGF-ß, more than free PGD2, indicating that microencapsulation increased the activating effect of PGD2 on cells. In LPS-pre-treated AMs, PGD2-MS decreased the release of IL-6 but increased the production of nitric oxide and IL-1ß. These results show that the morphological characteristics of PGD2-MS facilitated interaction with, and activation of phagocytic cells; moreover, PGD2-MS retained the biological activities of PGD2 to trigger effector mechanisms in AMs. It is suggested that PGD2-MS represent a strategy for therapeutic intervention in the lungs of immunocompromised subjects.

Hyaluronidase-loaded PLGA microparticles as a new strategy for the treatment of pulmonary fibrosis.

The aim of this work was to develop an innovative tool for the treatment of pulmonary fibrosis based on our previous findings, which demonstrated that intranasally administered soluble bovine hyaluronidase (HYAL) increases the numbers of mesenchymal (MSC)-like cells in the bronchoalveolar fluid (BALF) and thus reduces the bleomycin-induced fibrosis. To this end, we developed poly(D,L-lactide-co-glycolide) (PLGA) microparticles (MPs) loaded with HYAL (HYAL-MP) to preserve the enzyme's biological activity and to facilitate its delivery to the lung. Nonloaded MPs (Control-MPs) and HYAL-MPs were prepared using the emulsion and solvent evaporation methods and thoroughly characterized. The HYAL-MPs and Control-MPs exhibited an average diameter of 4.3±2.1 and 4.4±1.5 µm, respectively. The encapsulation efficiency of the HYAL-MPs was 68%, and encapsulation led to a reduced release rate. Additionally, the HYAL-MPs were efficiently phagocytosed by J-774.1 cells. Compared with the soluble HYAL, the HYAL-MPs increased the proportion of MSC-like cells in the BALF of C57BL6 mice 96 h after treatment. The efficacy of the HYAL-MPs was also tested in C57BL6 mice that were previously exposed to 4 U/kg of bleomycin to induce lung fibrosis. The results demonstrated that the HYAL-MPs reduced neutrophil recruitment after bleomycin treatment more effectively than did the soluble HYAL, whereas the Control-MPs did not exhibit any effect. The HYAL-MPs also reduced the bleomycin-induced fibrosis more efficiently, and 134% of the collagen deposition in the lung compared with the soluble HYAL and the Control-MPs. In summary, our data indicate that HYAL-MPs are an effective delivery system that could feasibly be used in the treatment of pulmonary fibrosis.

Biodegradable microspheres containing leukotriene B(4) and cell-free antigens from Histoplasma capsulatum activate murine bone marrow-derived macrophages.

Because of the potential protective role of leukotrienes (LTs) in histoplasmosis and the therapeutic and prophylactic effects of cell-free antigens from Histoplasmacapsulatum (CFAgs), the aim of this study was to develop and characterise biodegradable LTB(4)/CFAgs-loaded microspheres (MS) that could promote cellular activation for future immunisation purposes. LTB(4)/CFAgs-loaded MS that were developed through a double emulsion/extraction process were characterised according to their size, zeta potential, morphology, entrapment efficiency and in vitro release kinetics. We evaluated the uptake of LTB(4)/CFAgs-loaded MS by bone marrow derived-macrophages (BMDM). The TNF-α and chemokines, and nitrite production, in the supernatant of BMDM cultures were analysed by enzyme-linked immunosorbent assay (ELISA) and Griess reaction, respectively. We found an instantaneous release of CFAgs and a prolonged release of LTB(4) from the poly-(d,l-lactide-co-glycolide) (PLGA) MS. The microencapsulation process did not alter the zeta potential nor the spherical morphology of the MS. The appropriate size of the LTB(4)/CFAgs-loaded MS (smaller than 10µm) enabled the efficient uptake by BMDM and also induced TNF-α, CXCL1/KC, CCL2/MCP-1, CCL5/RANTES and nitrite oxide release by these cells. In conclusion, the biodegradable LTB(4)/CFAgs-loaded MS were able to efficiently activate murine BMDM and thereby have the potential to be used in an effective vaccine against H. capsulatum infection.

The adhesive system and root canal region do not influence the degree of conversion of dual resin cement.

OBJECTIVES: The aim of this study was to evaluate the influence of two adhesive systems and the post space region on the degree of conversion of dual resin cement and its bond strength to root dentin. MATERIAL AND METHODS: One three-step etch-and-rinse (All-bond 2, Bisco) and another one-step self-etch (Xeno III, Dentsply) adhesive systems were applied on 20 (n=10) crownless bovine incisors, at 12-mm-deep post space preparation, and a fiber post (DT Light Post, Bisco) was cemented using a dual cure resin cement (Duo-Link, Bisco). Three transverse sections (3 mm) were obtained, being one from each study region (cervical, middle and apical). The degree of conversion of the dual cure resin cement was determined by a micro-Raman spectrometer. The data (%) were submitted to repeated-measures analysis of variance and Tukey's test (p<0.05). RESULTS: For both groups, the degree of conversion means (%) (All bond 2cervical = 69.3; All bond 2middle = 55.1; All bond 2apical= 56; Xeno IIIcervical = 68.7; Xeno IIImiddle = 68.8; Xeno IIIapical = 54.3) were not significantly different along the post space regions (p<0.05). CONCLUSION: Neither the adhesive nor the post space region influenced the degree of conversion of the cement layer.

Leukotriene B4-loaded microspheres as a new approach to enhance antimicrobial responses in Histoplasma capsulatum-infected mice.

Histoplasmosis is a pulmonary disease characterised by chronic granulomatous and suppurative inflammatory reactions caused by Histoplasma capsulatum. Regarding new therapies to control fungal infections, the aim of this study was to investigate whether pulmonary administration of leukotriene B(4) (LTB(4))-loaded microspheres (MS) could confer protection to 5-lipoxygenase knockout (5-LO(-/-)) mice infected by H. capsulatum. In this study, MS containing LTB(4) were administered intranasally to mice infected by H. capsulatum. On Day 14 after the infection, fungal recovery from the lungs and histology were evaluated and inflammatory cytokines were measured. Pulmonary administration of LTB(4)-loaded MS was able to reduce fungal recovery from infected lungs. Production of important inflammatory cytokines related to host defence was augmented following MS administration to the lungs. Lung histology also showed that infected mice presented a clear reduction in the fungal burden following the pulmonary release of LTB(4) from MS. Our study provides evidence that the proposed biodegradable microparticulate system, which can release LTB(4) to the lungs, can be employed as therapy, enhancing the antimicrobial activity of host cells during histoplasmosis.

The adhesive system and root canal region do not influence the degree of conversion of dual resin cement

OBJECTIVES: The aim of this study was to evaluate the influence of two adhesive systems and the post space region on the degree of conversion of dual resin cement and its bond strength to root dentin. MATERIAL AND METHODS: One three-step etch-and-rinse (All-bond 2, Bisco) and another one-step self-etch (Xeno III, Dentsply) adhesive systems were applied on 20 (n=10) crownless bovine incisors, at 12-mm-deep post space preparation, and a fiber post (DT Light Post, Bisco) was cemented using a dual cure resin cement (Duo-Link, Bisco). Three transverse sections (3 mm) were obtained, being one from each study region (cervical, middle and apical). The degree of conversion of the dual cure resin cement was determined by a micro-Raman spectrometer. The data ( percent) were submitted to repeated-measures analysis of variance and Tukey's test (p<0.05). RESULTS: For both groups, the degree of conversion means ( percent) (All bond 2cervical = 69.3; All bond 2middle = 55.1; All bond 2apical= 56; Xeno III cervical = 68.7; Xeno IIImiddle = 68.8; Xeno III apical = 54.3) were not significantly different along the post space regions (p<0.05). CONCLUSION: Neither the adhesive nor the post space region influenced the degree of conversion of the cement layer.

Estudo comparativo entre dois métodos de aplicação de torque aos pilares protéticos em implantes de conexão externa / Comparative study between two methods of torque application on external hexagon implants abutments

O propósito do presente estudo foi avaliar o efeito do retorque na pré-carga de pilares protéticos fixados a implantes de conexão externa após diferentes tempos de espera. Trinta implantes de conexão externa (ScrewMaster®, Conexão) foram incluídos em resina acrílica. Sobre cada implante foi instalado um pilar protético(Ceraone®, Conexão) e, sobre estes, aparafusados os parafusos de fixação (30 Ncm), com o auxílio de um torquímetro digital. Os conjuntos implantes/pilares foram divididos em seis grupos, de acordo com os fatores "retorque" e "tempo de espera para coleta dos dados" (2, 5 e 10 min) (n = 5): aplicação de torque + coletade dados de destorque após 2 min (GA1), 5 min (GA2)e 10 min (GA3); aplicação de torque + retorque após10 min + coleta de dados de destorque após 2 min (GB1), 5 min (GB2) e 10 min (GB3). Os dados obtidos foram analisados estatisticamente pelos testes Anova (dois fatores) e Tukey (5%). As médias ± desvios-padrão dos valores de destorque (Ncm) observados para as condições experimentais foram: GA1: 25,39 ± 1,59; GA2: 22,91 ± 1,74; GA3: 21,95 ± 1,07; GB1: 28,16 ± 2,92; GB2: 21,97 ± 1,44; GB3: 21,21 ± 2,91. Verificou-se que os métodos de aplicação de torque (retorque) não influenciaram na perda de pré-carga para os grupos estudados (p = 0,6427 > 0,05) e que o tempo de espera para coleta dos dados do retorque afetou de maneira significativa os valores de pré-carga, sendo os maiores após 2 min da aplicação do torque (p = 0,0001 < 0,05). Conclui-se que houve perda significativa da pré-carga após 5 min da aplicação do torque.

The purpose of this study was to evaluate the effect of the retorquing on the preload of Ceraone abutment fixed to implants of external connection after different elapsed times for data collection. Thirty external hexagon implants (ConexãoTM, Brazil) were embedded in acrylic resin. After, the CeraoneTM abutments were fixed on each implant and the torque was applied (30Ncm). The sets of implant/abutment/screw were divided among six groups according to the factors “retorquing”and “elapsed times for data collection” (2, 5 and 10min) (n = 5): torque application + detorque data collection after 2min (GA1), 5min (GA2) and 10min (GA3) and torque application + new torque application (retorquing) after 10min + detorque data collection after 2min (GB1), 5min (GB2) and 10min (GB3). The data obtained were statistically analyzed by using the ANOVAtwo-way and Tukey test (5%). The means (± DP) of the detorque values (Ncm) observed for the experimental conditions were: GA1: 25.39 ± 1.59; GA2: 22.91± 1.74; GA3: 21.95 ± 1.07; GB1: 28.16 ± 2.92; GB2:21.97 ± 1.44; GB3: 21.21 ± 2.91. It was observed that the methods for torque application (retorquing) did not influence the lost of preload for the groups studied (p =0.6427 > 0.05) and that the elapsed time for retorquing data collection significantly affected the preload values,where the higher values were obtained after 2 min (p =0.0001 < 0.05) torque application. We concluded that regardless the methods used for torque application, there was a significant loss of preload after 5min torque application.

Avaliação da dureza Vickers de resinas compostas de uso direto e indireto / Evaluation of Vickers hardness of direct and indirect composite resins

Objetivo: Este estudo propôs avaliar a microdureza de diferentes resinas compostas de uso direto (rcd) e indireto (rci). Materiais e Métodos: Com o auxílio de uma matriz metálica (diâmetro: 5,0mm; espessura: 2,0mm) foram confeccionadas 70 amostras, sendo (n=10) três resinas de uso direto: Gr1- Z250(3M ESPE/EUA), Gr2- W3D(Wilcos/Brasil) e Gr3- Esthetic X(Dentisply/EUA); e quatro de uso indireto: Gr4- Resilab Master (Wilcos/Brasil), Gr5- Vita VM LC (Vita Zahnfabrik/Alemanha), Gr6- Vita Zeta (Vita Zahnfabrik/Alemanha) e Gr7- Sinfony (3M ESPE/EUA). As amostras das rcd foram confeccionadas utilizando a técnica incremental, onde cada incremento de resina foi fotopolimerizado durante 40 segundos. Já as amostras da rci foram polimerizadas segundo recomendações dos fabricantes. Todos os espécimes foram armazenados em água destilada a 37ºC durante 24 horas. O teste de microdureza foi realizado em microdurômetro digital (Future-Tech,Modelo FM 700), com carga de 50 kgf por 15 segundos. Os dados obtidos (Kgf/mm2) foram analisados utilizando o teste não paramétrico de Kruskal-Wallis e o de comparação múltipla de Dunn (p<0.05). Resultados: As medidas resumo-numéricas de microdureza obtidas foram (mediana; média ± desvio padrão): Gr1 (100,12; 101,07± 5,99 Kgf/mm2), Gr2 (83,55; 84,20± 5,07 Kgf/mm2), Gr3 (73,98; 73,95± 6,55 Kgf/mm2), Gr4 (52,50; 52,54± 5,9 Kgf/mm2), Gr5 (33,25; 34,36± 2,29 Kgf/mm2), Gr6 (29,60; 29.68± 1.52 Kgf/mm2), Gr7 (25,39; 25.13± 2.08 Kgf/mm2). Verificou-se que os valores de microdureza das rcd analisadas não diferiram estatisticamente entre si (p<0,05). O mesmo não se pode estabelecer para as resinas indiretas, pois a Sinfony diferiu da Resilab (p<0,05). Conclusão: Baseado nos resultados pôde-se concluir que apenas a resina composta direta Z250 apresentou valores de microdureza Vickers superior às demais resinas indiretas.

Efeitos do suco de laranja e da molhabilidade da cerâmica sobre a formação do in situ / The effects of orange juice and ceramic wettability on in situ biofi lm formation

Este estudo procurou determinar os parâmetros do biofilme formado in situ, em cerâmica de revestimento, de acordo com a disponibilidade de carboidrato (suco de laranja) e a molhabilidade da superfície cerâmica. Discos de duas cerâmicas foram feitos (Vita VM7 e VM13, Vita Zahnfabrik, Bad Sackingen, Alemanha). Quatro discos foram aderidos a dispositivos palatais usados por oito voluntários. Colocou-se três gotas da água destilada (pH=6) ou suco de laranja (pH=3,5) sobre os discos oito vezes/dia. Após 48 horas in situ, os dois discos mais palatais foram removidos do dispositivo e analisados com microscopia confocal de varredura a laser (MCVL) para caracterização do biofilme (espessura média, μm e biovolume, μm3/μm2). O ângulo de contato (°) foi medido nas superfícies polidas de espécimes controle, e após 15 dias de uso nos espécimes da região frontal do dispositivo palatal. Os dados foram submetidos à estatística descritiva e inferencial (Mann-Whitney e teste t, p < 0,05). A molhabilidade de ambas as cerâmicas não diferiu estatisticamente. A formação do biofilme sobre as cerâmicas de revestimento não foi influenciada pelo suco de laranja ou pela molhabilidade da cerâmica...

This study aimed to determine the in situ biofilm parameters on veneering ceramics, according to the carbohydrate (orange juice) availability and the ceramic surface wettability. Disks were made out of two veneering ceramics (Vita VM7 and VM13, Vita Zahnfabrik, Bad Sackingen, Alemanha). Four disks were bonded to palatal devices worn by eight volunteers. The subjects dripped three drops of distilled water (pH=6) or orange juice (pH=3.5) on the disks 8x/day. After 48 h in situ, the two palatal disks were removed from the device and analyzed by Confocal Laser Scanning Microscopy (CLSM) for biofilm characterization (mean thickness, μm and biovolume, μm3/ μm2). The contact angle (°) was measured on the polished surfaces of as sintered specimens and after 15 day of in situ usage, on the frontal disks of the palatal device. The data were subjected to descriptive and inferential (Mann-Whitney and paired-t test, at p < 0.05) statistics. The biofi lm parameters of VM13 were not measurable, whereas the VM7 biofilm parameters were not signifi cantly affected by the type of liquid. The wettability of both ceramics also did not differ statistically. The biofi lm formation on the veneering ceramics was neither influenced by the orange juice dripping nor the ceramics’ wettability...

Correlação entre as diferenças de monitoração inicial e final do ramo mandibular marginal associado à observação clínica durante parotidectomias / Correlation between the initial and final monitoring differences of the marginal mandible ramification associated to the clinical observation during parotidectomies

Introdução: a paresia ou paralisia do nervo facial é uma possível complicação da parotidectomia. Estímulos mecânicos ou elétricos ao nervo facial durante o processo cirúrgico e sua tradução em sinais auditivos e visuais, porém, podem facilitar a localização do nervo, diminuindo o risco de lesões. Objetivo: avaliar a associação da monitoração do nervo facial com a diminuição da incidência de paresia ou paralisia facial. Métodos: análise retrospectiva de 13 parotidectomias consecutivas realizadas no período de outubro de 2005 a julho de 2007. A monitoração contínua intra-operatória foi utilizada em todos os pacientes. Estabelecemos uma classificação para graduar a paresia do ramo mandibular marginal. Resultados: 46,15% dos pacientes apresentaram paresia transitória. Não foi observado nenhum caso de paralisia permanente. Das 13 parotidectomias realizadas, 10 foram superficiais e três profundas, portanto, totais. A incidência de paresia transitória nas parotidectomias totais ocorreu em todos os casos e, nas superficiais, 30%. Conclusão: A monitoração do nervo facial mostrou-se eficiente na preservação da integridade do nervo durante a parotidectomia. O estudo também sugere a associação da extensão da cirurgia com pior prognóstico.

Introduction: the paresis or facial nerve palsy is a possible complication of parotidectomy. Nevertheless, mechanical or electronic stimulus to the facial nerve during the surgical process and its translation into visual and auditory signs may facilitate the nerve localization, reducing the incidence of injuries. Objective: to evaluate the association between the facial nerve and the reduction in the incidence of facial paresis or palsy. Methods: retrospective analysis of 13 consecutive parotidectomies between October, 2005 and July, 2007. Continuous intraoperative monitoring was applied to all patients. A classification was established in order to graduate the different degrees of the marginal mandible ramification paresis. Results: 46.15% of the patients presented transitory paresis. There was no case of permanent palsy. Among the 13 parotidectomies performed, 10 were superficial and the other 3 included the deep lobe. The transitory paresis in the deep parotidectomies happened in all cases, whereas the incidence corresponded to 30% of the cases in the superficial ones. Conclusion: The facial nerve monitoring presented itself as an effective way of preserving the nerve integrity during the process of parotidectomy. This study also suggests the association between the surgery's extension and the worst prognosis.