Avaliação radiográfica e microscópica (MEV-Microscopia eletrônica de varredura), do preparo apical promovido por três diferentes técnicas para preparo biomecânico dos canais radiculares, empregando sistemas rotatórios

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Regeneração óssea de defeitos circunferenciais criados cirurgicamente ao redor de implantes submersos. Estudo experimental em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Calibração de tanques evaporímetros de baixo custo sob diferentes diâmetros em ambiente protegido

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência de Lactobacillus acidophilus sobre biofilme formado por Candida albicans in vitro e infecção em modelo de invertebrado

Pós-graduação em Biopatologia Bucal - ICT

Measurement of Radiant Energy using Pyroelectric Polymer/Ceramic Composite

Monitoring non-ionizing radiant energy is increasingly demanded for many applications such as automobile, biomedical and security system. Thermal type infrared (IR) sensors can operate at room temperature and pyroelectric materials have high sensitivity and accuracy for that application. Working as thermal transducer pyroelectric sensor converts the non-quantified thermal flux into the output measurable quantity of electrical charge, voltage or current. In the present study the composite made of poly(vinylidene fluoride) -PVDF and lead zirconate titanate (PZT) partially recovered with polyaniline (PAni) conductor polymer has been used as sensor element. The pyroelectric coefficient p(T) was obtained by measuring the pyroelectric reversible current, i.e., measuring the thermally stimulated depolarization current (TSDC) after removing all irreversible contribution to the current such as injected charge during polarization of the sample. To analyze the sensing property of the pyroelectric material, the sensor is irradiated by a high power light source (halogen lamp of 250 W) that is chopped providing a modulated radiation. A device assembled in the laboratory is used to change the light intensity sensor, an aluminum strip having openings with diameters ranging from 1 to 10 mm incremented by one millimeter. The sensor element is assembled between two electrodes while its frontal surface is painted black ink to maximize the light absorption. The signal from the sensor is measured by a Lock-In amplifier model SR530 -Stanford Research Systems. The behavior of the output voltage for an input power at several frequencies for PZT-PAni/PVDF (30/ 70 vol%) composite follows the inverse power law (1/ f) and the linearity can be observed in the frequency range used.

Caracterização radiográfica ex vivo de biomateriais utilizados para regeneração óssea em mandíbulas de porcos

Introduction: The radiographic characteristics of a biomaterial, such as its density, may influence the evaluation of the results obtained following its clinical use. Objective: The aim of this study was to evaluate the radiographic density of biomaterials used as bone substitutes, inserted into dental sockets and bone defects in created in the jaws of pigs. The influence of a soft tissue simulator on the results was also evaluated. Material and method: Two and three-millimeter-deep bone defects were created in the pigs mandible and the right first molar extraction socket were used. Commercial samples of five biomaterials were tested: Hydroxyapatite, Lyophilized Bovine Bone, 45S5 bioglass (generic), PerioGlass and β-Tri-Calcium Phosphate, and compared to a positive (mandibular bone) and negative (empty alveolar bone defects) controls. Radiographic images were acquired with and without a 10 mm thick soft-tissue simulator. Result: The results for the extraction sockets showed no differences between the biomaterials and the negative control. For the bone defects, the depth of the defect density influenced the density, both in the negative control (p < 0.01) and biomaterials (p < 0.05) groups. The soft- tissue simulator did not alter the results. Conclusion: The type of the evaluated defect can interfere in the radiographic features presented by each biomaterial, while the simulation of soft tissues was not statistically significant.

Bone-implant contact around crestal and subcrestal dental implants submitted to immediate and conventional loading

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Early loading of 6-mm-short implants with a moderately rough surface supporting single crowns: a prospective 5-year cohort study

AimTo evaluate prospectively the clinical and radiographic outcomes after 5years of early loading of 6-mm implants with a moderately rough (SLActive((R))) surface supporting single crowns in the posterior regions.Material and methodsThirty-five consecutive patients received 40 SLActive((R)) (Straumann) 6-mm implants with a diameter of 4.1mm (n=19) or 4.8mm (n=21). Insertion torque and resonance frequency analysis (RFA) were measured at implant installation. RFA was also measured at abutment connection. SynOcta abutments were tightened with 35Ncm after 6weeks of healing, and single porcelain fuse to metal crowns was cemented within 1week. Implant survival rate and marginal bone loss were evaluated at various time intervals until 5years after loading. The clinical crown/implant ratio was calculated as well.ResultsTwo of 40 implants were lost before loading (incorporation rate 95%), and no further implant loss or technical complications were encountered during the 5-year follow-up period. A mean marginal bone loss of 0.70.6mm was found after 5years of function. The clinical crown/implant ratio increased with time from 1.6 at the delivery of the prosthesis to 2 after 5years of loading.ConclusionSix millimeter implants with a SLActive((R)) moderately rough surface supporting single crowns in the posterior region and loaded after 6-7weeks maintained full function for at least 5year with low marginal bone resorption.

Lateral pterygoid muscle volume and migraine in patients with temporomandibular disorders

Lateral pterygoid muscle (LPM) plays an important role in jaw movement and has been implicated in Temporomandibular disorders (TMDs). Migraine has been described as a common symptom in patients with TMDs and may be related to muscle hyperactivity. This study aimed to compare LPM volume in individuals with and without migraine, using segmentation of the LPM in magnetic resonance (MR) imaging of the TMJ. Twenty patients with migraine and 20 volunteers without migraine underwent a clinical examination of the TMJ, according to the Research Diagnostic Criteria for TMDs. MR imaging was performed and the LPM was segmented using the ITK-SNAP 1.4.1 software, which calculates the volume of each segmented structure in voxels per cubic millimeter. The chi-squared test and the Fisher's exact test were used to relate the TMD variables obtained from the MR images and clinical examinations to the presence of migraine. Logistic binary regression was used to determine the importance of each factor for predicting the presence of a migraine headache. Patients with TMDs and migraine tended to have hypertrophy of the LPM (58.7%). In addition, abnormal mandibular movements (61.2%) and disc displacement (70.0%) were found to be the most common signs in patients with TMDs and migraine. In patients with TMDs and simultaneous migraine, the LPM tends to be hypertrophic. LPM segmentation on MR imaging may be an alternative method to study this muscle in such patients because the hypertrophic LPM is not always palpable.

Estudo da resistência à tração de cápsulas e troqueis metálicos cimentados, em função de alívio e retenção para o cimento

Pós-graduação em Odontologia Restauradora - ICT

Vibrational and rotational spectroscopy of (CD3OD)-C-13

We have used Fourier Transform spectral data on the C-O stretching mode of (CD3OD)-C-13 in order to perform a vibro-rotational analysis for this molecule. We have estimated a few molecular parameters of the ground and C-O stretching vibrational modes. Based on these parameters, and by using the Kwan-Dennison model, we propose assignments for a number of far-infrared laser transitions of (CD3OD)-C-13.

Caracterização petrográfica estrutural e metamorfica das rochas da região de Indiara (GO)

The region Indiara (GO) is located in southwestern of São Francisco Craton in the Internal Zone of the Brasília Belt, western part of the Tocantins Province. In this locality outcrop rocks of the Goiás Magmatic Arc. These rocks are muscovite gneiss with biotite, muscovite-biotite gneiss, biotite gneiss with muscovite and garnet, biotite-muscovite gneiss, muscovite porfiroclastic gneiss, biotite porfiroclastic gneiss, muscovite-quartz schists, garnetquartz schists, and metamafic rock (hornblende schists) as metric or kilometric lenses. The gneisses have granodioritic composition, granoblastic texture, with some portions with lepidoblastic texture, constituting a discontinuous centimeter to millimeter banding; the structure is anisotropic, marked by the preferred orientation of all the minerals. These gneisses are leucocratic, generally are inequigranular and fine to medium grained. The hornblende schists have nematoblastic texture, are inequigranular and fine to medium grained and have anisotropic structure that is given by a foliation, marked by a strong preferential orientation of the crystals of amphibole and other minerals present in the rock. The gneisses of the area are composed of plagioclase (oligoclase/andesine), quartz, microcline, muscovite, biotite, epidote, apatite, zircon, garnet, kyanite, oxides and hydroxides of iron and opaque minerals. And the metamafic rocks of Indiara region are composed mainly of amphibole, plagioclase (oligoclase/andesine), quartz, titanite, biotite, allanite, garnet, oxides and hydroxides of iron, apatite, epidote, rutile, muscovite and opaque minerals. At least three phases of deformation were observed in the rocks of area of study (Dn-1, Dn and Dn +1). The Dn phase and represented by a well-marked foliation Sn having low dip angle (average dip of 20 °) and dip direction to SW (210/21) and to NE (18/20); the Dn-1 phase is represented by a compositional banding (Sn- 1), this banding is generally...

Oral chronic graft-versus-host disease: analysis of dendritic cells subpopulations

The graft-versus-host disease is the major cause of morbidity and mortality in patients who have undergone hematopoietic stem cell transplantation. Aiming at contributing to the understanding of the role of myeloid and plasmacytoid dendritic cells, and natural killer cells in chronic graft-versus-host disease, we examined biopsies of jugal mucosa of 26 patients with acute myeloid leukemia who had undergone allogenic hematopoietic stem cell transplantation. Half of these patients developed oral chronic graft-versus-host disease. Microscopic sections were immunohistochemically stained for anti-CD1a, anti-CD123 and anti-CD56. We calculated the number of immunostained cells in the corium per square millimeter and applied the Mann-Whitney test. Results showed a statistically significant increase of myeloid dendritic cells (CD1a+; p=0,02) and natural killer cells (CD56; p=0,04) in patients with oral chronic graft-versus-host disease. CD123 immunostaining showed no statistical difference between groups. It was concluded that myeloid dendritic cells and natural killer cells participate in the development of oral chronic graft-versus-host disease.

Influence of pulp condition on the accuracy of an electronic foramen locator in posterior teeth: an in vivo study

The aim of this study was to assess, in vivo, the accuracy of the NovApex (R) electronic foramen locator in determining working length (WL) in vital and necrotic posterior teeth. The NovApex (R) was used in 144 canals: 35 teeth with vital pulps (68 canals) and 42 teeth with necrotic pulps (76 canals). WL was measured with the NovApex (R) locator and confirmed using the radiographic method. Differences between electronic and radiographic measurements ranging between 0.0 and 0.4 millimeters were classified as acceptable; differences equal to or greater than 0.5 millimeter were considered unacceptable. Pearson's chi-square test was used to assess the influence of pulp condition on the accuracy of NovApex (R) (alpha = 0.05). Regardless of pulp condition, differences between electronic and radiographic WL measurements were acceptable in 73.61% of the canals. No statistically significant differences in accuracy were observed when comparing vital and necrotic canals (p > 0.05). There were 38 unacceptable measurements. In none of these cases was the file tip located beyond the radiographic apex; in 32, it was located short of the NovApex (R) measurement. Pulp condition had no significant effect on the accuracy of NovApex (R).

Is 2-mm Punch Biopsy Useful in the Diagnosis of Malignant Eyelid Tumors?

Purpose: Two-millimeter punch biopsy is a swift and practical diagnostic tool in the outpatient setting. However, few studies have evaluated the efficacy of the method for diagnosis of malignant eyelid tumors. Methods: This was an observational study of patients with suspicion of malignant eyelid tumor attending the Ocular Plastic Surgery Center at Hospital das Clinicas, University of Sao Paulo School of Medicine. Following standard procedures, preoperative biopsies were taken with a 2-mm trephine and surgical excision was performed with safety margins, followed by reconstruction. Anatomopathologic analysis of the surgical specimen was used as gold standard to evaluate the accuracy of diagnosis by punch biopsy. Results: The study included 50 periocular tumors with suspicion of malignancy. The indicators of efficacy in the identification of malignancy by 2-mm punch biopsy were: sensitivity 88%, specificity 100%, positive predictive value 100%, and negative predictive value 64%. Accuracy was 90% for malignancy and 80% for histologic type. The. index of agreement between the diagnostic methods was 0.722 (p < 0.001). Conclusion: A positive result with 2-mm punch biopsy is a safe indication for surgical excision of the tumor, whereas a negative result does not necessarily imply benignity. In cases of high clinical suspicion, a second biopsy should be taken from a different part of the tumor to rule out malignancy. (Ophthal Plast Reconstr Surg 2012;28:282-285)