Objective. The aim of this study was to evaluate the rat subcutaneous tissue reaction to calcium hydroxide-based intracanal medicaments, UltraCal XS (calcium hydroxide, barium sulphate, aqueous matrix), Hydropast (calcium hydroxide, barium sulphate, and propyleneglycol), and Calen (Calcium hydroxide, zinc oxide, colophony, and polyethyleneglycol), used as a control. Methods. Forty-eight rats (Rattus Norvegicus Holtzman) were distributed in three groups: Calen, UltraCal XS, and Hydropast. Polyethylene tubes filled with one of the medicaments were implanted in the dorsal subcutaneous. After 7 and 30 days, the implants were removed and the specimens were fixed and embedded in paraffin. Morphological and quantitative analyses were carried out in the HE-stained sections. The numerical density of inflammatory cells in the capsule was evaluated and statistical analyses were performed (P ≤ 0.05). Results. At 7 days, all materials induced an inflammatory reaction in the subcutaneous tissue adjacent to the implants. In all groups, a significant reduction in the number of inflammatory cells and giant cells was verified in the period of 30 days. Conclusion. These results indicate that the calcium hydroxide-based medicaments evaluated present biocompatibility similar to Calen.

The aim of this study was to evaluate the effectiveness of 3 solvents (eucalyptol, orange oil, and xylol) on 2 types of gutta-percha (conventional and thermoplastic) and Resilon. Specimens (10 mm diameter x 1 mm thick; n=7 per condition) were prepared and maintained at 37 degrees C for 48 h. Each specimen was weighed on a precision scale every 24 h until its mass was stable, at which time the initial mass was determined. Specimens (n=7) were then immersed in the solvent solutions and, after 48 h at 37 degrees C, they were reweighed at 24- h intervals, until stabilization (final mass). The difference between the final and the initial mass determined the solvent capacity of each solvent. Data were subjected to analysis of variance and Tukey's test at 5% significance level. The results demonstrated that xylol was the most effective, especially on conventional gutta-percha and Resilon (p<0.05). Eucalyptol and orange oil were more effective on thermoplastic gutta-percha than the other materials (p<0.05). It was concluded that all evaluated substances presented solvent action, but xylol was the most effective on both gutta-percha or Resilon.

Pecan farming is a long-term investment which needs quality seedlings to establish an orchard. Pecan rootstocksmust have a vigorous radicular system to form quality seedlings. Liquid humus, which acts as an agent thatpromotes their growth and development, is a bioinput that is specially used in organic production systems.This study aimed at evaluating effects of different frequencies of liquid humus application on pecan rootstockgrowth and development in an organic system. Liquid humus at 30% was applied every 7, 14, 21 and 28 days.The control treatment consisted of water application. The experiment was carried out with ‘Barton’ rootstocksin a greenhouse at the Embrapa Clima Temperado located in Pelotas, RS, Brazil. The following variables wereevaluated 280 and 480 days after transplantation: plant height; stem diameter; leaf area; fresh and dry massesof the aerial part; main and secondary root lengths; fresh and dry masses of roots; fresh and dry masses of themain root; fresh and dry masses of secondary roots; and the Dickson Quality Index. Liquid humus increasedsecondary root length of pecan rootstocks, mainly when it was applied every seven days. Thus, the bioinputmay be used for this purpose.