Avaliação da eficiência de remoção, por técnica manual e ultrasônica, do hidróxido de cálcio associado a quatro veículos como medicação intracanal

Abstract

The aim of this study was to evaluate the efficiency of two calcium hydroxide removal techniques as intracanal medication. Ninety mandibular central incisors were transversally sectioned, in order to provide an 18mm standardization of the root in length. The canals were biomechanically prepared, then the roots were divided into 2 groups (n = 45): Group A manual technique of medication removal; and group B manual technique and ultrasound application. The intracanal medication used in each group was calcium hydroxide associated to different vehicles (n = 10), as follows: G1 saline solution; G2 PA; G3 Polyethyleneglycol; G4 Polyethyleneglycol + PMCC and G5 no medication (n = 5, control).The teeth were stored in a 100% moisture condition. After 7 days, the medication was removed and the roots were longitudinally sectioned. The inner portion of the canal was evaluated by means of digitalized photographic images, and the remaining portions were macroscopically quantized using the Imagetool software, taking into account the cervical, medium and apical thirds. According to the Kruskal-Wallis test, there were found statistically significant differences among Group A thirds, in the subgroup that used calcium hydroxide and saline. There were no statistically significant differences found in Group B thirds, regardless the subgroup assessed. When the root canal was considered as a whole, the Kruskal-Wallis test was applied, and only Group B presented statistically significant differences, among the 4 subgroups values, demonstrating that this removal was more efficient to the calcium hydroxide + saline solution. The Mann- Whitney U test compared groups A and B, verifying that only the calcium hydroxide + saline solution subgroups presented statistically significant differences, concluding that the manual technique enforced by an ultra-sound device had left less remaining residuals quantities of this association into the canals.