J Korean Acad Conserv Dent.  2009 May;34(3):232-239. 10.5395/JKACD.2009.34.3.232.

Effects of anticurvature filing on danger zone width in curved root canals

• Kim ES
• Kim HJ
• Seo DG
• Roh BD

• KMID: 2176149
• DOI: http://doi.org/10.5395/JKACD.2009.34.3.232

Abstract

The aim of this study was to compare the effects of anticurvature filing with stainless steel k-file versus nickel-titanium ProFile in the shaping of mesial root canals of extracted mandibular molars. A total of 60 canals from 30 mesial roots of mandibular molar teeth were randomly assigned to three groups with n=20 each. They were prepared with different instruments and methods: The first group with stainless steel k-file and circumferential filing, the second with precurved stainless steel k-file and anticurvature filing and the third with ProFile (.06 taper) and anticurvature filing. Using a micro-computed tomography system (skyscan-1076, SKYSCAN, Antwerpen, Belgium), pre-and post-operative specimens were scanned. Subsequently, canal images were superimposed and changes in root dentin thickness were measured at distal side (danger zone) of the canal. The data was analyzed using a one-way ANOVA and the comparison of means was conducted using a post hoc multiple comparison Tukey test. There were significant differences in the change of root dentin thickness at the 7.5~8.5mm level between group 1 and 2, 3.5~6mm level between group 1 and 3 and 3.5~6mm level between group 2 and 3(n=20, P<0.05).

Keyword

anticurvature filing; stainless steel k-file; nickel-titanium ProFile

MeSH Terms

Dental Pulp Cavity
Dentin
Molar
Stainless Steel
Tooth
Stainless Steel

Figure

• 

  Figure 1 Pre-and Post-instrumentation canal images were superimposed and changes in root thickness were measured at distal side (danger zone) of the canal using the CTAn. Blue line is distance to external root surface pre-op and red line is post-op.

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  Figure 2 Change of root dentin thickness(mm) by canal preparation at danger zone before and after. At 7.5-8.5mm, significant differences were shown between group 1 and group 2(n=20, P<0.05). At 3.5-6mm, significant differences were shown between group 1 and group 3(n=20, P<0.05). At 3.5-6mm, significant differences were shown between group 2 and group 3(n=20, P<0.05).

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  Figure 3 Comparison of group 1 and 2. The reconstructed 3-D root canal system before and after preparation is shown and superimposed cross-section images, which shows significant difference at 7.5-8.5mm level, are also shown. In group 2, more dentin was removed in the safe zone than in the danger zone at coronal 1/3 level.

• 

  Figure 4 Comparison of group 1 and 3. The reconstructed 3-D root canal system before and after preparation is shown and superimposed cross-section images, which shows significant difference at 3.5-6mm level, are also shown.

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