J Korean Acad Conserv Dent.  2008 Sep;33(5):435-442. 10.5395/JKACD.2008.33.5.435.

A comparison of master apical file size according to instrumentation in type II root canal

• Jeong EJ
• Lee DK
• Baek SY
• Hwang HK

• KMID: 1986781
• DOI: http://doi.org/10.5395/JKACD.2008.33.5.435

Abstract

Type II root canal was defined that two canals leave the chamber and merge to form a single canal at short of the apex. The aim of this study was to analyse the master apical file (MAF) size according to various instrumentation techniques in the type II root canal when each canal was enlarged to working length. Eighty mesial roots of molar with ISO #15 initial apical file (IAF) size in type II root canals were randomly divided into four experimental groups with 20 teeth each. According to enlarging instruments, four groups are: K-FLEXOFILE(R) (KF), engine-driven Ni-Ti PROTAPER(R) (PT), HERO Shaper(R) (HS), K3 (TM) (K3). All canals were enlarged to each working length with ISO #30 size: #30 in KF, F3 in PT, .04/30 in HS, and .06/30 in K3. The master apical file (MAF) size was confirmed by tactile sensation and universal testing machine (EZ test, Shimadzu Co., Kyoto, Japan). The mean MAF size was statistically compared using one-way ANOVA and Tukey HSD test at the 0.05 probability level. These results show that the MAF size was appeared one or two sizes larger than the final enlarging instrument when all canal in type II configuration were enlarged to each working length. Therefore, the clinician have to confirm the apical stop once more after instrumentation of type II root canal.

Keyword

Type II root canal; Master apical file; Initial apical file; Apical stop

MeSH Terms

Collodion
Dental Pulp Cavity
Molar
Nickel
Sensation
Titanium
Tooth
Collodion
Nickel
Titanium

Figure

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  Figure 1 The device for taking a standard radiogragh at same position.

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  Figure 2 The apparatus and EZ test for measuring Newton value when file removed.

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