Flexibility of K3 and ProTaper universal instruments.

This study used a mechanical test to evaluate the flexibility of instruments from the K3 (conicity 0.04) and the ProTaper Universal systems when they were new and after 5 uses in simulated canals. Five sets of instruments of each system were tested: K3 (15, 20, 25, 30, 35, 40 and 45) and ProTaper Universal (S1, S2, F1, F2, F3, F4 and F5).

Wear promoted in the apical third of simulated canals after instrumentation with ProTaper universal system.

Objective: This study evaluated the wear in the apical third of simulate canals after preparation with ProTaper Universal Rotary System.

Material And Methods: 24 sets of instruments were used in 24 simulated canals in transparent epoxy resin blocks with degree of curvature of either 20 degrees or 40 degrees. The canals were photographed preoperatively and after preparation of the apical stop with ProTaper F3, F4 and F5 instruments.

In vitro comparative study of manual and mechanical rotary instrumentation of root canals using computed tomography.

This in vitro study compared, using computed tomography (CT), the amount of dentin removed from root canal walls by manual and mechanical rotary instrumentation techniques. Forty mandibular incisors with dental crown and a single canal were selected. The teeth were randomly assigned to two groups, according to the technique used for root canal preparation: Group I - manual instrumentation with stainless steel files; Group II - mechanical instrumentation with RaCe rotary nickel-titanium instruments.

In vitro comparative analysis of 2 mechanical techniques for removing gutta-percha during retreatment.

Objective: To compare the capacity of a reciprocating system (Endo-Gripper) and a rotary system (Profile .04) for mechanical removal of root-filling material from curved root canals in vitro.

Materials And Methods: Eighty canals (40 mesiobuccal and 40 mesiolingual) from mandibular first molars were instrumented and had their roots filled.

Influence of cervical preflaring on determination of apical file size in maxillary molars: SEM analysis.

The purpose of this study was to investigate the influence of cervical preflaring on determination of the initial apical file in mesiobuccal roots of maxillary molars. Fifty first molars with degree of curvature of the mesiobuccal root between 10 degrees and 15 degrees were utilized. After standard access opening and removal of pulp tissue, the working length (WL) was determined at 1 mm from the root apex.

Treatment of invasive cervical resorption with MTA: case report.

This paper presents a case report of a maxillary lateral incisor affected by invasive cervical resorption. The tooth was submitted to a 21-day treatment with calcium hydroxide followed by root canal filling. The area of resorption was sealed with MTA followed by glass ionomer cement and restored with composite resin.

In vitro evaluation of the presence of apical deviation with employment of automated handpieces with continuous and alternate motion for root canal preparation.

The present study conducted an in vitro evaluation of the presence of apical deviation on the root canal preparation of the mesiobuccal roots of human maxillary molars employing automated handpieces with continuous motion, the Pow R system (Moyco Union Broach), and alternate motion, the M4 system (Kerr). Analysis of the presence of apical deviation was carried out by means of radiographs obtained on a radiographic desk fabricated for the study. The results demonstrated the lack of statistically significant differences between the two systems as to the evaluation of the presence of apical deviation.

Apical displacement produced by rotary nickel-titanium instruments and stainless steel files.

The aim of this study was to evaluate the apical displacement produced by different rotary nickel-titanium instruments, testing the hypothesis that rotary systems with nickel-titanium instruments produce lower mean values of apical displacement than stainless steel hand instruments. A total of 100 maxillary permanent first molars were selected for the study. The mesiobuccal roots were sectioned at the top cervical third and embedded in blocks of self-curing resin.