Apical Sealing Quality of In Vitro Apicectomy Procedures After Using Both Er:YAG and Nd:YAG

The aim of this study was to evaluate the apical sealing of dentinal tubules after root-end surface cutting by using Er:YAG and Nd:YAG lasers. After root-canal instrumentation and filling, apices of 50 extracted maxillary canine human teeth were resected by Er: YAG with 400 mJ, 10 Hz, for 30 sec. The samples were randomly assigned to five groups (n = 10): (GI) treated without root-end cavity, but with Nd: YAG (1.0W, 10 Hz, 20 sec) for dentinal tubules sealing; (GII) treated with root-end cavity without the use of Nd: YAG; (GIII) treated with root-end cavity and Nd: YAG application; (GIV) treated with root-end cavity made by Er: YAG with no focus and without Nd: YAG application; and (GV) treated without root-end cavity and without Nd: YAG application. The root-end cavities were performed by using Er: YAG at 300 mJ, 10 Hz, for 20 sec. Subsequently, all teeth were waterproofed and immersed in 2% methylene blue for 48 h in a vacuum environment. The samples were longitudinally sectioned, and microleakage was measured. ANOVA and the Fisher LSD test showed that GIV was less susceptible to microleakage than were the other groups (p < 0.05). Interestingly, the use of the Er: YAG with no focus showed superior dentinal tubule sealing in comparison with the other groups, even with or without root-end cavity and Nd: YAG application.

Influence of Sealer Placement Technique on the Quality of Root Canal Filling by Lateral Compaction or Single Cone

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Apical leakage after root canal filling with an experimental calcium hydroxide gutta-percha point

This study was an in vitro analysis of the apical seal of root canals filled with an experimental calcium hydroxide gutta-percha point. One hundred and ten recently extracted human permanent teeth with a single root were used. The root canals were biomechanically prepared, and some received a dressing of calcium hydroxide for 7 days. Root canals not dressed were filled by the lateral condensation technique with either regular gutta-percha or calcium hydroxide gutta-percha points. The dressed root canals were filled with the same sealers and regular gutta-percha points. The specimens were placed into a 2% methylene blue dye solution under vacuum, and the apical leakage was linearly evaluated. The experimental groups with calcium hydroxide dressing and the one with calcium hydroxide gutta-percha points exhibited significantly (p < 0.05) less leakage than the groups filled with regular gutta-percha points. The results obtained indicated that calcium hydroxide guttapercha points produced an improvement in the apical sealing quality of the root canal filling. Copyright © 1996 by The American Association of Endodontists.

Citotoxicidade, genotoxicidade e expressão gênica em células da polpa dental humana sensibilizadas por cimentos endodônticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The Scored Patient-Generated Subjective Global Assessment (PG-SGA) and its Association with Quality of Life in Ambulatory Patients Receiving Radiotherapy

OBJECTIVE: To evaluate the scored Patient-generated Subjective Global Assessment (PG-SGA) tool as an outcome measure in clinical nutrition practice and determine its association with quality of life (QoL). DESIGN: A prospective 4 week study assessing the nutritional status and QoL of ambulatory patients receiving radiation therapy to the head, neck, rectal or abdominal area. SETTING: Australian radiation oncology facilities. SUBJECTS: Sixty cancer patients aged 24-85 y. INTERVENTION: Scored PG-SGA questionnaire, subjective global assessment (SGA), QoL (EORTC QLQ-C30 version 3). RESULTS: According to SGA, 65.0% (39) of subjects were well-nourished, 28.3% (17) moderately or suspected of being malnourished and 6.7% (4) severely malnourished. PG-SGA score and global QoL were correlated (r=-0.66, P<0.001) at baseline. There was a decrease in nutritional status according to PG-SGA score (P<0.001) and SGA (P<0.001); and a decrease in global QoL (P<0.001) after 4 weeks of radiotherapy. There was a linear trend for change in PG-SGA score (P<0.001) and change in global QoL (P=0.003) between those patients who improved (5%) maintained (56.7%) or deteriorated (33.3%) in nutritional status according to SGA. There was a correlation between change in PG-SGA score and change in QoL after 4 weeks of radiotherapy (r=-0.55, P<0.001). Regression analysis determined that 26% of the variation of change in QoL was explained by change in PG-SGA (P=0.001). CONCLUSION: The scored PG-SGA is a nutrition assessment tool that identifies malnutrition in ambulatory oncology patients receiving radiotherapy and can be used to predict the magnitude of change in QoL.

Guidelines on building design and operation to minimize air quality impacts from major roads in transit oriented development

Poor air quality has a huge detrimental effect, both economic and on the quality of life, in Australia. Transit oriented design (TOD), which aims to minimise urban sprawl and lower dependency on vehicles, leads to an increasing number of buildings close to transport corridors. This project aims at providing guidelines that are appropriate to include within City Plan to inform future planning along road corridors, and provide recommendations on when mitigation measures should be utilised.