• Restorative Dentistry and Endodontics
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• v.29 no.2
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• pp.147-152
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• 2004

The purpose of this study was to investigate the quantity of debris which was extruded apically after canal instrumentation using different types of enlarging instrument in endodontic resin models. Five groups of 9 endodontic resin models were instrumented using each different technique : hand instrumentation without early coronal flaring. hand instrumentation after early coronal flaring. and three nickel-titanium engine-driven instrumentations (Hero 642, Protaper, $K^$). Debris extruded from apical foramen during instrumentation was collected on preweighed CBC bottle, desiccated and weighted using electronic balance. The results were analyzed using Kruskal-wallis test and Mann-Whitney U rank sum test at a significance level of 0.05. The results were as follows: 1. All of instrumentation techniques produced apically extruded debris. 2. Group without early coronal flaring extruded significant more debris than groups with early coronal flaring. 3. There was no significant difference among early coronal flaring groups. The early coronal flaring is very important to reduce the amount of debris extruded apically.

• Restorative Dentistry and Endodontics
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• v.46 no.2
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• pp.16.1-16.11
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• 2021

Objectives: The aim of this study was to evaluate the shaping ability of the TruShape and Reciproc Blue systems and the apical extrusion of debris after root canal instrumentation. The ProTaper Universal system was used as a reference for comparison. Materials and Methods: Thirty-three mandibular premolars with a single canal were scanned using micro-computed tomography and were matched into 3 groups (n = 11) according to the instrumentation system: TruShape, Reciproc Blue and ProTaper Universal. The teeth were accessed and mounted in an apparatus with agarose gel, which simulated apical resistance provided by the periapical tissue and enabled the collection of apically extruded debris. During root canal preparation, 2.5% sodium hypochlorite was used as an irrigant. The samples were scanned again after instrumentation. The percentage of unprepared area, removed dentin, and volume of apically extruded debris were analyzed. The data were analyzed using 1-way analysis of variance and the Tukey test for multiple comparisons at a 5% significance level. Results: No significant differences in the percentage of unprepared area were observed among the systems (p > 0.05). ProTaper Universal presented a higher percentage of dentin removal than the TruShape and Reciproc Blue systems (p < 0.05). The systems produced similar volumes of apically extruded debris (p > 0.05). Conclusions: All systems caused apically extruded debris, without any significant differences among them. TruShape, Reciproc Blue, and ProTaper Universal presented similar percentages of unprepared area after root canal instrumentation; however, ProTaper Universal was associated with higher dentin removal than the other systems.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.580-580
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• 2003

I. Objectives This study investigated the quantity of debris which was extruded apically after canal instrumentation using different types of enlarging instrument in endodontic resin models. II. Materials and Methods Five groups of 9 endodontic resin model were instrumented using each different technique：hand instrumentation without early coronal flaring, hand instrumentation after early coronal flaring, and three nickel-titanium engine-driven instrumentations(Hero 642, Protaper, K3) after early coronal flaring.(omitted)

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.33.1-33.10
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• 2020

Objectives: This study was conducted to evaluate the effects of traditional and contracted endodontic cavity (TEC and CEC) preparation with the use of Reciproc Blue (RPC B) and One Curve (OC) single-file systems on the amount of apical debris extrusion in mandibular first molar root canals. Materials and Methods: Eighty extracted mandibular first molar teeth were randomly assigned to 4 groups (n = 20) according to the endodontic access cavity shape and the single file system used for root canal preparation (reciprocating motion with the RCP B and rotary motion with the OC): TEC-RPC B, TEC-OC, CEC-RPC B, and CEC-OC. The apically extruded debris during preparation was collected in Eppendorf tubes. The amount of extruded debris was quantified by subtracting the weight of the empty tubes from the weight of the Eppendorf tubes containing the debris. Data were analyzed using 1-way analysis of variance with the Tukey post hoc test. The level of significance was set at p < 0.05. Results: The CEC-RPC B group showed more apical debris extrusion than the TEC-OC and CEC-OC groups (p < 0.05). There were no statistically significant differences in the amount of apical debris extrusion among the TEC-OC, CEC-OC, and TEC-RPC B groups. Conclusions: RPC B caused more apical debris extrusion in the CEC groups than did the OC single-file system. Therefore, it is suggested that the RPC B file should be used carefully in teeth with a CEC.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.4
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• pp.213-221
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• 2022

Purpose: The efficacy of the amount of sealer in the root canal and two retreatment NiTi file systems in removing filling materials. Materials and Methods: Extracted premolars with a single root canal were selected for this study. After access opening and root canal preparation up to size #40/.06, the specimens were randomly divided into four groups. Gutta percha (GP) tapers of .06 or .04 were used for each group and filled using a single-cone filling technique with CeraSeal, a calcium silicate-based sealer. Each group was retreated either using the ProTaper Universal Retreatment System (PTUR) or the Hyflex Remover (HR). The time taken to remove the filling material, the amounts of apically extruded debris, and canal cleanliness were measured and compared. Results: The amount of sealer did not affect the efficiency when removing the filling materials. However, the filling material was removed faster in the HR group than in the PTUR group. Two types of NiTi files showed similar retreatment effects in the amounts of apically extruded debris and in the degree of canal cleanliness. Conclusion: The amount of sealer in canal filling had no significant effect on retreatability. Retreatment with HR removed filling materials is faster than PTUR. There was no difference in other removal efficiencies according to the type of retreatment NiTi file.

• Restorative Dentistry and Endodontics
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• v.42 no.4
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• pp.316-323
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• 2017

Objectives: This study compared the amount of apically extruded bacteria during the glide-path preparation by using multi-file and single-file glide-path establishing nickel-titanium (NiTi) rotary systems. Materials and Methods: Sixty mandibular first molar teeth were used to prepare the test apparatus. They were decoronated, blocked into glass vials, sterilized in ethylene oxide gas, infected with a pure culture of Enterococcus faecalis, randomly assigned to 5 experimental groups, and then prepared using manual stainless-steel files (group KF) and glide-path establishing NiTi rotary files (group PF with PathFiles, group GF with G-Files, group PG with ProGlider, and group OG with One G). At the end of canal preparation, 0.01 mL NaCl solution was taken from the experimental vials. The suspension was plated on brain heart infusion agar and colonies of bacteria were counted, and the results were given as number of colony-forming units (CFU). Results: The manual instrumentation technique tested in group KF extruded the highest number of bacteria compared to the other 4 groups (p < 0.05). The 4 groups using rotary glide-path establishing instruments extruded similar amounts of bacteria. Conclusions: All glide-path establishment instrument systems tested caused a measurable apical extrusion of bacteria. The manual glide-path preparation showed the highest number of bacteria extruded compared to the other NiTi glide-path establishing instruments.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.399-407
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• 1999

Apical extrusion of canal debris is occurred inadvertently during root canal preparation and this could produce interappointment discomfort or postinstrumentation pain. The purpose of this study was to investigate the influence of canal preparation methods on the apical extrusion of canal debris by means of comparing the amounts of apically extruded debris with several kinds of instrumentation methods. In the first experiment, 40 incisors were divided into four groups of 10 each. They were instrumented using one of the four techniques: Step-back, crown-down pressureless technique with stainless steel K-files, engine-driven instrumentation with Quantec series 2000, and Profile .04 taper series 29. Root canal irrigation was done with 2.52% sodium hypochlorite solution. In the second experiment, 80 incisors were divided into five groups of 16 each and instrumented using step-back, crown-down pressureless technique with stainless steel K-files, engine-driven instrumentation such as Quantec SC, Quantec LX, and Profile .04 taper series 29 No irrigation procedure was performed in this second experiment. Extruded debris from each tooth was collected in a container and weighed by the use of an electronic balance after desiccation. With or without canal irrigation, step-back technique produced significantly more amount of apical debris than the other groups (p<0.05). However, there was no significant difference among crown-down pressureless technique, engine-driven instrumentation with Quantec LX, Quantec SC, or Profile. Therefore, either by hand or engine-driven instrumentation, it is concluded that to minimize apical debris, techniques using reaming motion of files should be applied rather than filing motion.