Information for the diagnosis and treatment of root resorption due to tooth replantation

A favorable prognosis after tooth avulsion depends on some variables, such as the extra-alveolar period and storage medium. Vitality of the periodontal ligament cells is considered a critical factor for a successful outcome without root resorption. The dental surgeon is provided with clinical information and radiographic findings to establish a diagnosis and may rely on current available guidelines. Once trauma has occurred, treatment must be quick and effective, and periodic follow-up must be performed. Clinical, radiographic, and histologic characteristics for each type of root resorption due to tooth replantation are presented, with the aim to provide information for the diagnosis and treatment of healing complications.

Single-use Trocar Is it Possible to Reprocess it After the First Use?

The aim of this study was to verify and describe the presence of microorganisms in the single-use trocar after its use in surgical procedures, and after this device was submitted to cleaning, conditioning, and sterilization by physicochemical processes (formaldehyde, ethylene oxide, and hydrogen peroxide plasma). Twenty-eight trocars of the Ethicon, Auto-suture, and Aesculap brands, were randomly selected and analyzed after laparoscopic cholecystectomy. The results have shown that cultures grown of the material collected from the trocars, immediately after its use and before its sterilization process, showed the presence of bacteria and fungi in 46.5% (13). In 53.5% (15) of the trocars, the presence of microorganisms was not detected, very likely due to niche`s scarcity. In the cultures grown of the 28 trocars after being submitted to sterilization processes, the presence of microorganisms was not verified. We can therefore conclude that although trocars possess compartments not easily accessed for cleaning, these devices can be adequately cleaned and effectively sterilized, when well manipulated, in the institution where the study was carried out by the processes of steam sterilization at low temperature and formaldehyde, ethylene oxide, and hydrogen peroxide plasma.

Structural and spectroscopic properties of the diazocarbene radical (CNN) and its ions CNN(+) and CNN(-): a high-level theoretical investigation

The diazocarbene radical, CNN, and the ions CNN(+) and CNN(-) were investigated at a high level of theory. Very accurate structural parameters for the states X(3)Sigma(-) and A(3)Pi of CNN, and X(2)Pi of both CNN(+) and CNN(-) were obtained with the UCCSD(T) method using correlated-consistent basis functions with extrapolations to the complete basis set limit, with valence only and also with all electrons correlated. Harmonic and anharmonic frequencies were obtained for all species and the Renner parameter and average frequencies evaluated for the Pi states. At the UCCSD(T)/CBS(T-5) level of theory, Delta(f)H(0 K) = 138.89 kcal/mol and Delta(f)H(298 K) = 139.65 kcal/mol were obtained for diazocarbene; for the ionization potential and the electron affinity of CNN, 10.969 eV (252.95 kcal/mol), and 1.743 eV (40.19 kcal/mol), respectively, are predicted. Geometry optimization was also carried out with the CASSCF/MRCI/CBS(T-5) approach for the states X(3)Sigma(-) A(3)Pi, and a(1)Delta of CNN, and with the CASSCF/MRSDCI/aug-cc-pVTZ approach for the states b(1)Sigma(+), c(1)Pi, d(1)Sigma(-), and B(3)Sigma(-), and excitation energies (T(e)) evaluated. Vertical energies were calculated for 15 electronic states, thus improving on the accuracy of the five transitions already described, and allowing for a reliable overview of a manifold of other states, which is expected to guide future spectroscopic experiments. This study corroborates the experimental assignment for the vertical transition X (3)Sigma(-) <- E (3)Pi.

Agar-based films for application as polymer electrolytes

New types of polymer electrolytes based on agar have been prepared and characterized by impedance spectroscopy, X-ray diffraction measurements, UV-vis spectroscopy and scanning electronic microscopy (SEMI). The best ionic conductivity has been obtained for the samples containing a concentration of 50 wt.% of acetic acid. As a function of the temperature the ionic conductivity exhibits an Arrhenius behavior increasing from 1.1 x 10(-4) S/cm at room temperature to 9.6 x 10(-4) S/cm at 80 degrees C. All the samples showed more than 70% of transparency in the visible region of the electromagnetic spectrum, a very homogeneous surface and a predominantly amorphous structure. All these characteristics imply that these polymer electrolytes can be applied in electrochromic devices. (C) 2009 Elsevier Ltd. All rights reserved.

Plasticized pectin-based gel electrolytes

Pectin is a natural polymer present in plants and, as all natural polymers has biodegradation properties. Chemically, pectin is a polysaccharide composed of a linear chain of 1 -> 4 linked galacturonic acids, which is esterified with methanol at 80%. The pectin-based gel electrolytes in a transparent film form were obtained by a plasticization process with glycerol and addition of LiClO(4). The films showed good ionic conductivity results, which increased from 10(-5) S/cm for the samples with 37 wt.% of glycerol to 4.7 x 10(-4) S/cm at room temperature for the sample with 68 wt.% of glycerol. The electrochemical behaviors of the samples were studied by electrochemical impedance spectroscopy (EIS), and Nyquist graphs are showed and discussed. The obtained pectin-based samples also presented good adherence to the glass, flexibility, homogeneity (SEM) and transparency (about 70% in the vis) properties. They are good candidates to be applied as gel electrolytes in electrochromic devices. (C) 2009 Elsevier Ltd. All rights reserved.

Thermal behavior and structural properites of plant-derived eugenyl acetate

Eugenol is an allyl chain-substituted guaiacol in the biosynthesized phenylpropanoid compound class derived from Syzygium aromaticum L. and widely used in folk medicine. Nonetheless, its pharmacological use is limited by some problems, such as instability when exposed to light and high temperature. In order to enhance stability, the eugenol molecule was structurally modified, resulting in eugenyl acetate. The eugenyl acetate`s thermal behavior and crystal structure was then characterized by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) and compared to a commercial sample.

Characterization of the raw essential oil eugenol extracted from Syzygium aromaticum L.

Eugenol is the main volatile compound extracted oil from clove bud, Syzygium aromaticum L., and used in traditional medicine, as a bactericide, fungicide, anesthetic, and others. Its extraction was performed using hydrodistillation which is the most common extraction technique. Its components and thermal behavior were evaluated using gas chromatography (GC) and differential scanning calorimetry (DSC), which provide a better characterization of these natural compounds. This extracted product was compared to the standard eugenol results. The GC results suggested similar to 90% eugenol was found in the total extracted oil, and some of its boiling characteristics were 270.1 A degrees C for peak temperature and 244.1 J g(-1) for the enthalpy variation.