Effect of coronal flaring on apical extrusion of debris during root canal instrumentation using single-file systems.
OBJECTIVE
To evaluate the effect of coronal flaring on the amount of debris extruded apically during root canal preparation using the Reciproc, WaveOne (WO) and OneShape (OS) single-file systems.


METHODS
Ninety extracted single-rooted mandibular incisor teeth were randomly assigned to six groups (n = 15 for each group) for canal instrumentation. Endodontic access cavities were prepared in each tooth. In three of the six groups, coronal flaring was not performed; coronal flaring was performed with Gates-Glidden drills on all teeth in the remaining three groups. The canals were then instrumented with one or other of the following single-file instrument systems: Reciproc, WO and OS. Debris extruded apically during instrumentation was collected into pre-weighed Eppendorf tubes. The tubes were then stored in an incubator at 70 °C for 5 days. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and post-instrumentation weight of the Eppendorf tubes for each group. Data were analysed using one-way analysis of variance (anova) and Tukey's post hoc tests (P = 0.05).


RESULTS
Reciproc and WO files without coronal flaring produced significantly more debris compared with the other groups (P < 0.05). There was no significant difference in apical extrusion of debris amongst the other groups (P > 0.05).


CONCLUSIONS
All single-file systems caused apical extrusion of debris. Performing coronal flaring prior to canal preparation reduced the amount of apically extruded debris when using Reciproc or WO systems.
Department of Endodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
H S
HS
Topçuoğlu
Department of Endodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
Y
Y
Üstün
Department of Endodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
F
F
Akpek
Department of Endodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
A
A
Aktı
Department of Pedodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
G
G
Topçuoğlu
D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000601:surgery*; D006801:Humans; D066298:In Vitro Techniques; D007180:Incisor / Q000601:surgery; D008334:Mandible; D011897:Random Allocation; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D019227:Tooth Apex
coronal flaring; debris; extrusion; single-file system