Shaping ability of NiTi rotary versus stainless steel hand instruments in simulated curved canals

Abstract

Objectives: The purpose of this in-vitro study was to compare shaping ability of NiTi rotary Mtwo and FlexMaster with stainless steel hand K-Flexofile in simulated curved root canals. Study Design: Forty-five simulated canals in resin blocks were prepared with Mtwo, FlexMaster and stainless steel hand K-Flexofile (15 blocks in each group). Using pre-and post-instrumentation images, straightening of the canal curvature was determined with a computer image analysis program. Material removal was measured at 5 measuring points, beginning 1 mm from the apex. Changes of working length (WL) were also recorded. The data were analyzed statistically using paired T-test and one way ANOVA. Results: The mean material removal from the inner canal wall was different from the outer canal wall at all measuring points for each system (p < 0.0001) except for FlexMaster at WL-9 (p = 0.123) and K-Flexofile at WL-5 (p = 0.093). The mean ratio of material removal (inner/outer) at all measuring points was different for all systems except for FlexMaster and Mtwo at 3, 5 mm (p = 0.984, p = 0.242), and K-Flexofile and rotary systems at 1, 3 mm from the apex (p = 0.565, p = 0.218) (p = 0.794, p = 0.693). A mean loss of working length of 0.02 mm for Mtwo and 0.01 mm for FlexMaster and K-Flexofile was measured although the difference was not significant. Conclusions: In the apical points of the curvature (1, 3 mm), there was no significant difference between three systems. At point 5mm from the apex, K-Flexofile remained better centered, while in the coronal points (7, 9 mm) NiTi rotary systems achieved better canal geometry.

Shaping Ability of NiTi Rotary versus Stainless-Steel Hand Instruments in Curved Root Canals of Extracted Teeth

“…(1,5,7,9) However, shaping ability of these instruments in curved extracted human teeth was different from results obtained in resin blocks using the same instruments. (3) One possible reason for these differences may be due to the characteristics of the samples, their surface texture, hardness and cross section. (11) Using rotary instruments in resin blocks generate heat (2) which may soften the resin material and lead to binding of cutting blades (10) and influence shaping ability of these instruments.…”

“…A number of studies have compared shaping ability of NiTi rotary instruments versus stainless steel hand files either in simulated curved canals of resin blocks or in curved root canals of extracted teeth. (1)(2)(3)(4)(5)(6)(7)(8)(9)(10) Comparing the shaping ability of different instruments in standardized root canals of resin blocks do not reflect the action of the instruments in root canals of real teeth. (11) Thus, studies using real root canals in extracted teeth are required in order to fully assess the cleaning and shaping efficiency of root canal instruments.…”

“…(5) Recently, shaping ability of two new NiTi rotary Mtwo and FlexMaster systems were compared with stainless steel hand K-Flexofiles in simulated curved canals. (3) The primary aim of this in-vitro study was to compare shaping ability of NiTi rotary Mtwo and Flex Master with stainless steel hand K-Flexofile in curved root canals of extracted teeth with a more exact method than generally used in endodontic research. The second aim was to compare shaping ability of NiTi rotary Mtwo with FlexMaster system.…”

Influence of Prior Cervical Enlargement on Apical Cleaning Using Single File

“…This means that the clinical success of the endodontic treatment may be undermined 10,12) . Several types of endodontic rotary instrument have been developed with a view to optimizing such treatment, which has led to the gradual replacement of manual with mechanical instruments 10,17,22) . Such rotary instruments are designed to facilitate faster, higher-quality root canal preparation, reducing stress on both the professional and the patient during endodontic therapy 4,7,28) .…”

Mtwo ve S5 NiTi döner kanal eğelerinin yapay kök kanalını şekillendirme etkinliklerinin karşılaştırılması

“…Bu bulgu birkaç araştırmayla doğrulanmaktadır. 5,20,21,24 Schäfer ve ark. 5 yapmış oldukları bir çalışmada Mtwo eğelerde kırılma gözlenmediğini fakat K3 ve RaCe eğelerde daha sık deforme olduklarını bildirmiş-lerdir.…”