Effect of Different Speeds of Up-and-down Motion on Canal Centering Ability and Vertical Force and Torque Generation of Nickel-titanium Rotary Instruments

Maki, Keiichiro; Ebihara, Arata; Kimura, Shunsuke; Nishijo, Miki; Tokita, Daisuke; Okiji, Takashi

doi:10.1016/j.joen.2018.10.002

Cited by 28 publications

(38 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although there are no standardized specifications, a 2-mm pecking distance was chosen to facilitate comparison with a previous study 28) . An up-and-down speed of 50 mm/min was chosen based on a previous study 21) . Clinically, however, the pecking distance and speed are controlled manually and can be variable even within an operator.…”

Section: Discussionmentioning

confidence: 99%

“…The model was connected to the torque/force measuring unit. The handpiece attached to the moving stage of the stand was programmed to repeat an up-and-down movement at 50 mm/min for 2 and 1 s in the apical and coronal direction, respectively 20,21) . The maximum values were recorded.…”

Section: Evaluation Of Torque and Vertical Forcementioning

confidence: 99%

“…Pre-and post-instrumentation images of the root canal models were taken with a digital microscope (VH-8000, Keyence, Osaka, Japan), and superimposed with image processing software (Photoshop 7.0, Adobe Systems, San Jose, CA, USA). The canal-centering ratio 0, 0.5, 1, 2, and 3 mm from the apex was calculated by the following formula: (amount of resin removed from the outer side-amount of resin removed from the inner side)/ post-instrumentation canal diameter 21) . In this formula, a value of 0 indicates perfect centering.…”

Section: Canal-centering Abilitymentioning

confidence: 99%

See 2 more Smart Citations

Comparative evaluation of mechanical properties and shaping performance of heat-treated nickel titanium rotary instruments used in the single-length technique

et al. 2021

Self Cite

View full text Add to dashboard Cite

This study aimed to evaluate the mechanical properties of contemporary heat-treated nickel-titanium (NiTi) rotary instruments used in the single-length technique [ProTaper Next (PTN), HyFlex EDM (EDM), and JIZAI (JZ)]. Bending loads, cyclic fatigue resistance, torque/force values and canal-centering ratios were evaluated for the three instruments and a non-heat-treated experimental NiTi instrument with the same geometry as JZ (nJZ). EDM and JZ exhibited significantly lower bending load and more cycles to failure compared with nJZ and PTN (p<0.05). PTN and JZ exhibited significantly better centering ability than nJZ and EDM (p<0.05). JZ and nJZ generated significantly smaller upward force and maximum torque than PTN and EDM (p<0.05). Under the present experimental condition, JZ exhibited flexibility and cyclic fatigue resistance comparable to EDM, better maintained the canal curvature than the other instruments, and generated smaller torque and screw-in force than PTN and EDM.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Evaluation Of Torque and Vertical Forcementioning

confidence: 99%

Section: Canal-centering Abilitymentioning

confidence: 99%

See 1 more Smart Citation

Comparative evaluation of mechanical properties and shaping performance of heat-treated nickel titanium rotary instruments used in the single-length technique

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…An original device described in our previous articles [19][20][21][22] was used with a few modifications. The device consists of an endodontic motor (X-Smart Plus, Dentsply Sirona, Ballaigues, Switzerland), a motorized test stand (MX2-500N, Imada, Aichi, Japan), and a torque/force measuring unit.…”

Section: Automated Root Canal Instrumentation and Torque/force Analyzmentioning

confidence: 99%

“…The canal-centering ratio was determined using image analyzing software (Photoshop 7.0, Adobe Systems, San Jose, CA, USA), according to our previous study 22) (Fig. 1).…”

Section: Measurement Of Canal-centering Ratiomentioning

confidence: 99%

Enhanced root canal-centering ability and reduced screw-in force generation of reciprocating nickel-titanium instruments with a post-machining thermal treatment

et al. 2020

Self Cite

View full text Add to dashboard Cite

This study aimed to evaluate the influence of a post-machining thermal treatment on canal-centering ability and torque/force generation of reciprocating nickel-titanium instruments. Simulated J-shaped resin canals were prepared with reciprocating instruments sharing identical geometric architecture and with/without post-machining thermal treatment (Reciproc Blue/Reciproc, VDW, Munich, Germany). Using an original automated root canal instrumentation and torque/force analyzing device, files were operated in a combination of reciprocation and up-and-down motion, and torque/force values were monitored. Canal-centering ratios were measured after superimposition of pre-and post-instrumentation images. Compared with Reciproc, Reciproc Blue showed a significantly lower canal-centering ratio (i.e., less deviation; p<0.05) at 0-1 mm from the apex and generated a significantly smaller upward maximum vertical force (p<0.05). Under standardized conditions using the automated device, Reciproc Blue showed better canal-centering ability and reduced screw-in forces than Reciproc, indicating that the post-machining thermal treatment confers superior performance to reciprocating nickel-titanium instruments.

show abstract

Shaping ability of three instrumentation system in moderately curved canals: A micro‐CT study

Yanık,

Özel

2024

Microscopy Res & Technique

View full text Add to dashboard Cite

This study aims to compare the shaping ability of three systems using micro‐computed tomography (micro‐CT). Moderately‐curved mesial canals of 36 mandibular molars were assigned to three groups (n = 24); Protaper Next (PTN, 0.25, 0.06), WaveOne Gold (WOG, 0.25, 0.07), TruNatomy (TRN, 0.25, 0.04), and instrumentation was performed. Pre‐ and post‐micro‐CT scans were obtained. Canal volume and surface, structure model index (SMI), centroid shift, canal transportation, and untouched canal were analyzed. One‐way ANOVA and Student's t‐test were used for statistics. There was no difference in SMI, centroid shift, and centering ability between the study groups (p > .05). Removed dentin and canal surface changes were lower in TRN, while untouched dentin walls were higher (p < .05). Cross‐sections became more rounded (p < .05), but not significant between groups (p > .05). Considering the removed dentin by TRN, it can be used in critical dentin thickness, such as the danger zone (DZ). PTN, WOG, and WOG kept the original canal course similarly. Untouched dentin by TRN (41%) was wider than PTN and WOG, consequently, meticulous irrigation is recommended. TRN, which provides a controlled increase in canal volume, can be used in thin dentin such as the DZ, however, its use should be supported by copious irrigation and brushing considering the rate of untouched dentin walls.Research Highlights TRN presented a higher untouched dentin wall compared to PTN and WOG. Canal volume and surface changes were the lowest in the TRN group. The centering abilities were similar in PTN, WOG, and TRN.

show abstract

Effect of Different Speeds of Up-and-down Motion on Canal Centering Ability and Vertical Force and Torque Generation of Nickel-titanium Rotary Instruments

Cited by 28 publications

References 33 publications

Comparative evaluation of mechanical properties and shaping performance of heat-treated nickel titanium rotary instruments used in the single-length technique

Comparative evaluation of mechanical properties and shaping performance of heat-treated nickel titanium rotary instruments used in the single-length technique

Enhanced root canal-centering ability and reduced screw-in force generation of reciprocating nickel-titanium instruments with a post-machining thermal treatment

Shaping ability of three instrumentation system in moderately curved canals: A micro‐CT study

Contact Info

Product

Resources

About