A variation on split-cast mounting for complete denture construction

dThis article describes a variation of the split-cast mounting technique wherein the border of the definitive cast is wrapped with masking tape to form a container for the dental plaster normally used to affix the cast to the articulator. The entire inferior surface of the cast is coated with a thin film of petroleum jelly, and the cast is mounted in the articulator. After the dental plaster has set, the cast is retained by means of the masking tape. The cast is separated from the dental plaster simply by removing the masking tape.

High sinterability of Ca-PZT, synthesized by polymeric and partial oxalate process

This study includes Ca-PZT in the morphotropic phase boundary, MPB process combining the Pechini method, (ZT) and the Partial oxalate method (Ca-PZT) by obtaining single phase particles of ZT phase with a high specific surface area (similar to 110 m(2)/g at 550 degrees C) and narrow particle size distribution. Lead and calcium oxalates were precipitated onto the ZT particle surface and reacted to a solid state interface ZT/Ca-PZT/PbO-CaO. A deviation of a coexistence region from F-T- and F-R-phases to F-R-phase (Zr rich region) was observed. Strong surface area reduction occurs by Ca-PZT crystallization at about 700 degreesC, and demonstrated high sinterability (2.40 m(2)/g - 350 nm) with apparent densities near to 99.9%. Different processing methods did not demonstrate superior results. Studies of calcined powder shows a high sinterability of powder calcined 3 h at 700 degrees C and sintered 3 h at 1000 degreesC coming up to 99.8% of relative density. (C) 2001 Kluwer Academic Publishers.

Effect of partial preferential orientation and distortions in octahedral clusters on the photoluminescence properties of FeWO4 nanocrystals

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

Air-drying of fresh and osmotically pre-treated pineapple slices: Fixed air temperature versus fixed slice temperature drying kinetics

In this investigation, the air drying characteristics of fresh and osmotically pre-treated pineapple slices in a tray dryer were studied under different operating conditions. The air velocity varied from 1.5 to 2.5 m/s and the air temperature from 40 to 70 degreesC. The analytical solution of the second Fick's law for an infinite slab was used to calculate effective diffusion coefficients and their temperature dependence could be well represented by an Arrhenius-type equation. Comparison of the results showed that the diffusion coefficients were lower for the pre-treated fruit. By means of automatic control, it was possible to obtain drying curves under conditions of constant product temperature, which showed to be an alternative to reduce the drying time of pineapple slices.

LH and FSH concentration and follicular development in Nellore heifers submitted to fixed-time artificial insemination protocols with different progesterone concentrations

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

A clinical follow-up study of the periodontal conditions of RPD abutment and non-abutment teeth

The purpose of this study was to evaluate the periodontal conditions of removable partial denture (RPD) wearers, comparing direct and indirect abutment teeth, and the teeth not involved in the denture design before denture placement and 1 year later. Fifty patients (32 women and 18 men), average age 45, were assessed by the same examiner at the moment of denture insertion and 3, 6, 9 and 12 months later. The following items were verified in each assessment: probing depth (PD), plaque index (PI) and gingival index (GI). PD and PI data were evaluated by ANOVA test for linear trend followed by Tukey-Kramer post-test, while GI data were analysed by Friedman's test. Results showed that the teeth not involved in the denture design were the least affected for all variables studied. It was also verified that PD and GI mean values increased from the initial assessment to 1 year of RPD wearing in every group, but that only PI showed a significant increase. This study indicated that direct and indirect retainer elements tend to undergo more damaging periodontal effects associated with RPD wearing when compared with non-abutment elements. Plaque index values were significantly higher after 1 year of denture use.