Evaluation of pH and calcium ion diffusion from calcium hydroxide pastes and MTA.

The aim of this ex vivo study was to evaluate changes in pH and calcium ion diffusion through root dentin from calcium hydroxide (Ca (OH) ) and mineral trioxide aggregate (MTA) pastes at 7, 30 and 60 days; and the relationship between pH and ion diffusion. Thirty-two human premolars were used. Crowns were sectioned and root canals instrumented and filled in with the following preparations: 1) Ca(OH) + distilled water (n=7); 2) Ca(OH) + 0.

Apical extrusion of debris by manual and mechanical instrumentation.

The aim of the present study was to assess the presence of apically extruded debris and evaluate the influence of canal curvature on the amount of debris produced by manual and mechanical techniques. Forty single-rooted mature teeth with 15 to 30 degree of root canal curvature were selected. The presence of only one foramen was confirmed using a magnifying lens.

Shaping of curved root canals instrumented with stainless steel and nickel titanium files.

The cleaning efficiency and the quality of the surgical preparation is mainly conditioned by root canal anatomy, the instruments and the technique employed. The purpose of the present study was to evaluate the extent of straightening of curved root canals and the changes in endodontic anatomy caused by the use of Flex-R, Onyx-R and Nitiflex files with the balanced forces technique. Sixty mandibular molars were selected for evaluation of angulation and transportation.

Transportation of curved canals instrumented with manual and mechanical techniques.

The purpose of this study was to compare the effect of manual and mechanical instrumentation techniques in curved root canals using area of dentine removed and canal axis movement as the end-points. Sixty mandibular molars with curved root canals with angulations ranging from 15 degrees to 45 degrees were selected. The teeth were embedded in transparent resin in a grilon key-like muffle using Bramante's procedure.