The penetration of root canal sealers into dentinai tubules. A scanning electron microscopic study

The purpose of this study was to evaluate the effect of smear layer on penetration of four root canal sealers into dentinai tubules. Sixty-four, recently extracted, human maxillary and mandibular incisors were used. Following removal of the crowns, the pulps were extirpated and the root canals instrumented. The teeth were then divided into two groups. The teeth in the control group were irrigated with saline solution and the experimental group treated with EDTA and NaOCl. Each main group was then divided into four sub-groups and the root canals Oiled with Diaket, N2 Universal, SPAD and Forfenan as recommended by the manufacturers. The teeth were split longitudinally and examined using scanning electron microscopy. A quantitative assessment was made of sealer penetration into the dentinai tubules in the coronal, middle and apical parts of each root canal. It was observed that the smear layer obstructed the penetration of the tubules by the sealers. However, in the experimental group, the penetration into dentinai tubules was better with Diaket, N2 and SPAD, than with Forfenan (P > 0.01). It was concluded that this penetration could be affected by physical and chemical properties of root canal illing materials.