جستجوی مقالات مرتبط با کلیدواژه « protaper » در نشریات گروه « پزشکی »

 This study investigated the amount of debris and smear layer remaining followed chemomechanical preparation using three systems: ProTaper Universal, reciprocating SafeSider, and hand K-Flexofiles with scanning electron microscope (SEM). 

 Sixty-five mandibular molars with mesiobuccal canal curvature (25 to 40°) were extracted and divided into one control group (n=5), and three experimental groups (n=20) according to the preparation method; K-Flexofile, ProTaper Universal and SafeSider instruments. All canals were irrigated with 3 ml of 5.25% sodium hypochlorite solution and 3 mL of 17% EDTA. Subsequently, the canals were irrigated with 5 ml of normal saline. Then the teeth were examined under the scanning electron microscope (SEM). Kruskal-Wallis, Dunn-Q Bonferroni, and Friedman tests were used for statistical analysis of results. 

 To assess the accumulation of debris, statistically significant differences were observed only in the coronal area among ProTaper Universal, SafeSider, K-Flexofile, and the control group. (P=0.029). To evaluate the residual smear layer amount, statistically significant differences were observed only in the coronal and middle areas, following the preparation of the canals using ProTaper Universal, SafeSider, and hand K-Flexofiles and control groups (P=0.019). 

 Based on the present in vitro study, we can declare that the canals were utterly cleaned of debris and smear layer in none of the groups. Manual Flexofile and ProTaper Universal groups result in cleaner canal walls than reciprocal SafeSider, in the coronal and middle thirds.

Instrumentation with rotary instruments could potentially cause dentinal cracks possibly leading to tooth fracture. Reciproc files require a single file to finalize the root canal preparation and the effect of this procedure has not been compared with other systems.

The aim of this study was to compare the incidence of dentinal micro-cracks following root canal preparations with ProTaper, Mtwo and Reciproc files.

In an experimental in vitro trial, 80 maxillary and mandibular first molars were selected and their crowns and distal roots were cut. The roots were then examined to remove any previous cracks and defects. An impression polyether material was used to simulate teeth periodontal ligament (PDL). The teeth were divided to four experimental groups (n = 20) and prepared using Reciproc, Mtwo and ProTaper or remained unprepared as a control group. The specimens were then sectioned horizontally on 3, 5 and 9 mm from the apex and number of micro-cracks was determined by stereomicroscope. The incidence of dentinal cracks on different systems or sections were statistically analyzed by means of the chi-square test.

Dentinal defects on 3-mm, 5-mm and 9-mm sections from the apex were noted in 10 (5.6%); 7 (3.9%) and 9 (5.0%) samples of all, respectively. Following canal preparation using Reciproc, ProTaper and Mtwo systems, the defects were observed in 7 (3.9%), 12 (6.7%) and 7 (3.9%) the sections, respectively. No significant differences were observed regarding the defect incidence on the studied instrumentation files or sections.

Regarding the study limitations, dentinal cracks were observed in all files and distances from the apex. Although there was more crack incidence in ProTaper files, no significant differences were noted regarding the studied systems and sections from the apex