Periapical tissue healing after post space preparation with or without use of a protection plug and root canal exposure to the oral environment. Study in dogs

The purpose of this study was to evaluate the influence of coronal leakage on the healing of dogs' periapical tissues after root canal filling, post space preparation and protection or not with a temporary sealer plug. Forty root canals of dogs' teeth were instrumented and filled by the lateral condensation technique with gutta-percha points and Endomethasone or CRCS sealers. After post space preparation, the remaining filling material was protected or not with a plug of temporary Coltosol sealer and exposed to the oral environment for 90 days. Thereafter, the animals were sacrificed and the specimens were removed and prepared for histomorphological and histobacteriological analysis. The findings revealed 35% of microbial leakage in the groups without plugs and 15% of leakage in the groups with plugs. Statistical analysis showed that the use of a Coltosol plug improved significantly the histomorphological results regardless of the type of root canal sealer (p=0.05) and that CRCS and Endomethasone sealers showed similar results (p>0.05).

Influence of brush type as a carrier of adhesive solutions and paper points as an adhesive-excess remover on the resin bond to root dentin

Purpose: To evaluate the influence of the brush type as a earner of priming adhesive solutions and the use of paper points as a remover of the excess of these solutions on the push-out bond strength of resin cement to bovine root dentin. The null hypotheses were that brush type and the use of paper points do not affect the bond strength. Materials and Methods: The canals of 80 single-root bovine roots (16 mm in length) were prepared at 12 mm using the preparation drill (FRC Postec Plus, Ivoclar). Half of each root was embedded in acrylic resin and the specimens were divided into 8 groups, considering the factors brush type (4 levels) and paper point (2 levels) (n = 10): Gr 1: small microbrush (Cavi-Tip, SDI); Gr 2: Microbrush (Dentsply); Gr 3: Endobrush (Bisco); Gr 4: conventional brush (Bisco); Gr 5: Cavi-Tip (SDI) + paper points; Gr 6: Microbrush (Dentsply) + paper points; Gr 7: Endobrush (Bisco) + paper points; Gr 8: conventional brush (Bisco) + paper points. The root dentin was treated with a multistep total-etch adhesive system (All Bond 2). The adhesive system was applied using each microbrush, with and without using paper points. One fiber post was molded with addition silicon and 80 posts were made of resin cement (Duolink), The resin posts were luted (Duolink resin cement), and the specimens were stored for 24 h in water at 37°C. Each specimen was cut into 4 disk-shaped samples (1.8 mm in thickness), which were submitted to the push-out test. Results: The brush type (p < 0.0001) (small microbrush > microbrush = endobrush = conventional brush) and the use of paper points (p = 0.0001) (with > without) influenced the bond strength significantly (two-way ANOVA). The null hypotheses were rejected. Conclusion: The smallest brush (Cavi-Tip) and the use of paper points significantly improved the resin bond to bovine root dentin.

Fatigue resistance of bovine teeth restored with resin-bonded fiber posts: Effect of post surface conditioning

This study evaluated the effect of post surface conditioning on the fatigue resistance of bovine teeth restored with resin-bonded fiber-reinforced composite (FRC). Root canals of 20 single-rooted bovine teeth (16 mm long) were prepared to 12 mm using a preparation drill of a double-tapered fiber post system. Using acrylic resin, each specimen was embedded (up to 3.0 mm from the cervical part of the specimen) in a PVC cylinder and allocated into one of two groups (n = 10) based on the post surface conditioning method: acid etching plus silanization or tribochemical silica coating (30 μm SiOx + silanization). The root canal dentin was etched (H2PO3 for 30 seconds), rinsed, and dried. A multi-step adhesive system was applied to the root dentin and the fiber posts were cemented with resin cement. The specimens were submitted to one million fatigue cycles. After fatigue testing, a score was given based on the number of fatigue cycles until fracture. All of the specimens were resistant to fatigue. No fracture of the root or the post and no loss of retention of the post were observed. The methodology and the results of this study indicate that tribochemical silica coating and acid etching performed equally well when dynamic mechanical loading was used.

Comparison of resin push-out strength to root dentin of bovine- and human-teeth

Aim : To compare the push-out strength of bovine- and human-root dentin and, thus, evaluate the suitability of bovine-root dentin to substitute human-root dentin for bond strength testing. Materials and Methods : Ten single-rooted human-teeth and ten bovine incisors were prepared using a #3 bur of a fiber post system (12 mm long). The posts were duplicated with resin cement (Duolink). The root canals were treated with All Bond 2 adhesive system and the resin posts were cemented using Duolink. The specimens were cut perpendicular to their long axis, yielding disc-specimens with 1.5 mm thickness, which were submitted to a push-out test (1 mm/min). Ten bond strength values per group (n = 10) were used for statistical analysis (Student t test, a =.05). Results : Statistically significant differences were found for the bond strength values between bovine- (4.1 1.3 MPa) and human-root dentin (8.6 5.7 MPa) (P =.0001). Conclusion : The push-out strengths of bovine- and human-root dentin were statistically different.

Stress distribution on dentin-cement-post interface varying root canal and glass fiber post diameters. A three-dimensional finite element analysis based on micro-C data

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

Interactions between restorative dentistry and periodontics: luting post nonmetallic (Part II)

Endodontically treated teeth have necessary use of intracanal posts. Due to the constant need and search for esthetic materials with properties similar to tooth structure remaining fi berglass posts esthetic came good these shortcomings and are increasingly used as a fi rst option for prosthetic rehabilitation. In this case report is described step by step how to perform the cementation of a nonmetallic post and core construction for making a piece prosthetic onlay in a simplifi ed way, by choosing the self-etching cementation technique.

Design and implementation of wireless sensor networks for impedance-based structural health monitoring using ZigBee and Global System for Mobile Communications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resistive polymer versus forced-air warming: comparable heat transfer and core rewarming rates in volunteers

BACKGROUND: Mild perioperative hypothermia increases the risk of several severe complications. Perioperative patient warming to preserve normothermia has thus become routine, with forced-air warming being used most often. In previous studies, various resistive warming systems have shown mixed results in comparison with forced-air. Recently, a polymer-based resistive patient warming system has been developed. We compared the efficacy of a standard forced-air warming system with the resistive polymer system in volunteers. METHODS: Eight healthy volunteers participated, each on two separate study days. Unanesthetized volunteers were cooled to a core temperature (tympanic membrane) of 34 degrees C by application of forced-air at 10 degrees C and a circulating-water mattress at 4 degrees C. Meperidine and buspirone were administered to prevent shivering. In a randomly designated order, volunteers were then rewarmed (until their core temperatures reached 36 degrees C) with one of the following active warming systems: (1) forced-air warming (Bair Hugger warming cover #300, blower #750, Arizant, Eden Prairie, MN); or (2) polymer fiber resistive warming (HotDog whole body blanket, HotDog standard controller, Augustine Biomedical, Eden Prairie, MN). The alternate system was used on the second study day. Metabolic heat production, cutaneous heat loss, and core temperature were measured. RESULTS: Metabolic heat production and cutaneous heat loss were similar with each system. After a 30-min delay, core temperature increased nearly linearly by 0.98 (95% confidence interval 0.91-1.04) degrees C/h with forced-air and by 0.92 (0.85-1.00) degrees C/h with resistive heating (P = 0.4). CONCLUSIONS: Heating efficacy and core rewarming rates were similar with full-body forced-air and full-body resistive polymer heating in healthy volunteers.

Understanding heterogeneity in post-implementation enterprise system usage: towards a fit/misfit-experience-outcome typology

The overarching objective of this dissertation is to uncover why and how individually experienced fits and misfits translate into different outcomes of user behavior and satisfaction and whether these individual fit/misfit outcomes are in line with organizational intent. In search of patterns and possible archetype users in the context of ES PIPs, this dissertation is the first study that specifically links the theoretical concepts of the aggregated individual fit experiences with the individual and organizational outcome of these experiences (i.e. behavioral reaction, user satisfaction, and alignment with organizational intent). The case study’s findings provide preliminary support for four archetype users characterized by specific fit/misfit experience-outcome patterns.

Balanced bilinguals favor lexical processing in their opaque language and conversion system in their shallow language

Referred to as orthographic depth, the degree of consistency of grapheme/phoneme correspondences varies across languages from high in shallow orthographies to low in deep orthographies. The present study investigates the impact of orthographic depth on reading route by analyzing evoked potentials to words in a deep (French) and shallow (German) language presented to highly proficient bilinguals. ERP analyses to German and French words revealed significant topographic modulations 240-280ms post-stimulus onset, indicative of distinct brain networks engaged in reading over this time window. Source estimations revealed that these effects stemmed from modulations of left insular, inferior frontal and dorsolateral regions (German>French) previously associated to phonological processing. Our results show that reading in a shallow language was associated to a stronger engagement of phonological pathways than reading in a deep language. Thus, the lexical pathways favored in word reading are reinforced by phonological networks more strongly in the shallow than deep orthography.

PanPlot - software to visualize profiles and core logs

The program PanPlot was developed as a visualization tool for the information system PANGAEA. It can be used as a stand-alone application to plot data versus depth or time or in a ternary view. Data input format is tab-delimited ASCII (e.g. by export from MS-Excel or from PANGAEA). The default scales and graphic features can individualy be modified. PanPlot graphs can be exported in platform-specific interchange formats (EMF, PICT) which can be imported by graphic software for further processing.

CompactRIO: advanced data acquisition systems integration in CODAC Core System

Las herramientas de configuración basadas en lenguajes de alto nivel como LabVIEW permiten el desarrollo de sistemas de adquisición de datos basados en hardware reconfigurable FPGA muy complejos en un breve periodo de tiempo. La estandarización del ciclo de diseño hardware/software y la utilización de herramientas como EPICS facilita su integración con la plataforma de adquisición y control ITER CODAC CORE SYSTEM (CCS) basada en Linux. En este proyecto se propondrá una metodología que simplificará el ciclo completo de integración de plataformas novedosas, como cRIO, en las que el funcionamiento del hardware de adquisición puede ser modificado por el usuario para que éste se amolde a sus requisitos específicos. El objetivo principal de este proyecto fin de master es realizar la integración de un sistema cRIO NI9159 y diferentes módulos de E/S analógica y digital en EPICS y en CODAC CORE SYSTEM (CCS). Este último consiste en un conjunto de herramientas software que simplifican la integración de los sistemas de instrumentación y control del experimento ITER. Para cumplir el objetivo se realizarán las siguientes tareas: • Desarrollo de un sistema de adquisición de datos basado en FPGA con la plataforma hardware CompactRIO. En esta tarea se realizará la configuración del sistema y la implementación en LabVIEW para FPGA del hardware necesario para comunicarse con los módulos: NI9205, NI9264, NI9401.NI9477, NI9426, NI9425 y NI9476 • Implementación de un driver software utilizando la metodología de AsynDriver para integración del cRIO con EPICS. Esta tarea requiere definir todos los records necesarios que exige EPICS y crear las interfaces adecuadas que permitirán comunicarse con el hardware. • Implementar la descripción del sistema cRIO y del driver EPICS en el sistema de descripción de plantas de ITER llamado SDD. Esto automatiza la creación de las aplicaciones de EPICS que se denominan IOCs. SUMMARY The configuration tools based in high-level programing languages like LabVIEW allows the development of high complex data acquisition systems based on reconfigurable hardware FPGA in a short time period. The standardization of the hardware/software design cycle and the use of tools like EPICS ease the integration with the data acquisition and control platform of ITER, the CODAC Core System based on Linux. In this project a methodology is proposed in order to simplify the full integration cycle of new platforms like CompactRIO (cRIO), in which the data acquisition functionality can be reconfigured by the user to fits its concrete requirements. The main objective of this MSc final project is to develop the integration of a cRIO NI-9159 and its different analog and digital Input/Output modules with EPICS in a CCS. The CCS consists of a set of software tools that simplifies the integration of instrumentation and control systems in the International Thermonuclear Reactor (ITER) experiment. To achieve such goal the following tasks are carried out: • Development of a DAQ system based on FPGA using the cRIO hardware platform. This task comprehends the configuration of the system and the implementation of the mandatory hardware to communicate to the I/O adapter modules NI9205, NI9264, NI9401, NI9477, NI9426, NI9425 y NI9476 using LabVIEW for FPGA. • Implementation of a software driver using the asynDriver methodology to integrate such cRIO system with EPICS. This task requires the definition of the necessary EPICS records and the creation of the appropriate interfaces that allow the communication with the hardware. • Develop the cRIO system’s description and the EPICS driver in the ITER plant description tool named SDD. This development will automate the creation of EPICS applications, called IOCs.

Colour reflectance and core descriptions from sediment cores from the Weddell Sea

The timing of the last maximum extent of the Antarctic ice sheets relative to those in the Northern Hemisphere remains poorly understood. We develop a chronology for the Weddell Sea sector of the East Antarctic Ice Sheet that, combined with ages from other Antarctic ice-sheet sectors, indicates that the advance to and retreat from their maximum extent was within dating uncertainties synchronous with most sectors of Northern Hemisphere ice sheets. Surface climate forcing of Antarctic mass balance would probably cause an opposite response, whereby a warming climate would increase accumulation but not surface melting. Our new data support teleconnections involving sea-level forcing from Northern Hemisphere ice sheets and changes in North Atlantic deep-water formation and attendant heat flux to Antarctic grounding lines to synchronize the hemispheric ice sheets.