K-Flex Files (k-flex + file)

Distribution by Scientific Domains

Selected Abstracts

A survey of interfacial forces used during filing of root canals

J. D. Regan
Abstract , The pattern of dentine removal during endodontic instrumentation is influenced by many factors including the interfacial forces applied by the operator. The aim of this study was to investigate the influence of operators and different sizes and types of instruments on the magnitude of these interfacial forces. Single-rooted teeth were mounted on a cantilevered aluminium beam to which two pairs of single element strain gauges were joined in a half-bridge configuration and mounted at right angles to each other. The strain gauges were connected to an analogue-to-digital converter fitted in a micro-computer via conditioning amplifiers. This enabled strains to be recorded over a period of time. Twenty operators instrumented root canals using a series of hand instruments for 1 min each. The mean interfacial forces used by operators demonstrated a wide variation ranging from 9.06 g to 149.42 g (range of forces from 0,331 g) but there was a consistency in the relative magnitude for each operator. The 20 operators could be divided into 13 groups which were significantly different (,=0.05) from each other. There were significant differences (,=0.05) between the forces used for each of the K-Flex files (15, 25, 35, 45, and 70), the force increasing with the file size. There was also a significant difference (,=0.05) in the forces used between the Flexofile (#25) and the #25 K-Flex and Hedström files. However, there was no significant difference between the K-Flex and Hedström files. [source]

Apical transportation created using three different patency instruments

J. A. Gonzalez Sanchez
Gonzalez Sanchez JA, Duran-Sindreu F, Albuquerque Matos M, Garcia Carabaño T, Mercade Bellido M, Morello Castro S, Roig Cayón M. Apical transportation created using three different patency instruments. International Endodontic Journal 43, 560,564, 2010. Abstract Aim, To evaluate root canal transportation at the major foramen through the use of stainless steel size 08 K-Flex files, size 10 reamers, and XF finger spreaders when used as patency instruments. Methodology, One hundred and two mesiobuccal canals of maxillary and mandibular first molars were randomly divided into three groups (34 canals each). Size 08 stainless steel K-Flex files, size 10 stainless steel reamers and stainless steel XF finger spreaders were used as patency instruments in groups A, B and C respectively. The major foramen was photographed before and after instrumentation. The images were superimposed and then evaluated using Photoshop® to determine the frequency of apical transportation. The statistic analysis was performed using ,2test. Results, Transportation was detected in 22% of the specimens; 9% in group A, 12% in group B and 44% in group C. Significant differences were observed between groups A and C (P = 0.0025) and between groups B and C (P = 0.0069), but not between groups A and B (P = 1.00). Conclusions, No transportation was found in the majority of the samples when size 08 K-Flex files and size 10 stainless steel reamers were used. The XF finger spreaders, when used to maintain apical patency, caused the greatest transportation of the major foramen. [source]

Efficacy of ProTaper Universal rotary retreatment system for gutta-percha removal from root canals

L.-S. Gu
Abstract Aim, To evaluate the efficacy of the ProTaper Universal rotary retreatment system for gutta-percha (GP) removal from root canals. Methodology, Root canals of 60 extracted human maxillary anterior teeth were prepared and filled with laterally condensed GP and AH Plus sealer. Teeth were divided into three groups: group A , GP removal completed with the ProTaper Universal rotary retreatment system and with further canal repreparation accomplished with ProTaper Universal rotary instruments; group B , GP removal was completed using Gates Glidden drills and Hedström files with chloroform as a solvent, followed with further canal repreparation with ProTaper Universal rotary instruments; group C , the same as group B for GP removal with further canal preparation with stainless steel K-flex files (Kerr). The operating time was recorded. Teeth were rendered transparent for the evaluation of the area of remaining GP/sealer in bucco-lingual and mesial,distal directions. Statistical analysis was performed by using repeated measures analysis of variance and anova. Results, The ProTaper Universal technique (group A) resulted in a smaller percentage of canal area covered by residual GP/sealer than in groups B and C, with a significant difference between groups A and C (P < 0.05). Mean operating time for group A was 6.73 min, which was significantly shorter (P < 0.05) than group B (10.86 min) and group C (13.52 min). Conclusions, In this laboratory study all test techniques left GP/sealer remnants within the root canal. The ProTaper Universal rotary retreatment system proved to be an efficient method of removing GP and sealer from maxillary anterior teeth. [source]