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A Micro–Computed Tomographic Analysis of Wall Thickness of C-shaped Canals in Mandibular First Premolars

      Abstract

      Introduction

      The purpose of this study was to quantitatively evaluate the wall thickness of C-shaped canals in mandibular first premolars using micro–computed tomographic imaging. The focus was on the relation between the radicular groove and the mesial canal wall thickness.

      Methods

      A total of 148 mandibular first premolars were scanned by a micro–computed tomographic scanner. After 3-dimensional reconstruction of the teeth, 29 specimens were identified to contain a C-shaped canal, and then they were analyzed in software Mimics 10.01 (Materialise, Leuven, Belgium). The buccal and lingual canal wall thickness, minimum mesial and distal wall thickness, and the depth and angle of radicular grooves were measured at different root levels. Two-way analyses of variance and the post hoc Tukey's honestly significant difference test were used to compare the groups in relation to canal wall thickness.

      Results

      The buccal and lingual canal walls were significantly (P < .005) thicker than the mesial and distal walls. The minimum thickness of the mesial walls was significantly (P < .005) lower than that of the distal walls, and the locations were frequently at lingual sites, with an incidence of 67.3% for the mesial walls and 69.2% for the distal walls. Backward multivariate analysis showed that the root level and groove angle contributed significantly (P < .005) to the minimum mesial wall thickness.

      Conclusions

      The mesial walls of C-shaped canals in mandibular first premolars are the thinnest zones. The minimum mesial wall thickness decreases with the increased severity of the radicular groove, and it mainly occurs at lingual sites. Care should be taken to avoid perforation at danger zones during shaping and post space preparation procedures.

      Key Words

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      References

        • Slowey R.R.
        Root canal anatomy. Road map to successful endodontics.
        Dent Clin North Am. 1979; 23: 555-573
        • Lu T.Y.
        • Yang S.F.
        • Pai S.F.
        Complicated root canal morphology of mandibular first premolar in a Chinese population using the cross section method.
        J Endod. 2006; 32: 932-936
        • Vertucci F.J.
        Root canal anatomy of mandibular permolars.
        J Am Dent Assoc. 1978; 97: 47-50
        • Cleghorn B.M.
        • Christie W.H.
        • Dong C.C.
        The root and root canal morphology of the human mandibular first premolar: a literature review.
        J Endod. 2007; 33: 509-516
        • Fan B.
        • Yang J.
        • Gutmann J.L.
        • et al.
        root canal systems in mandibular first premolars with C-shaped root configurations. Part I: microcomputed tomography mapping of the radicular groove and associated root canal cross-sections.
        J Endod. 2008; 34: 1337-1341
        • Scott R.G.
        • Turner II, C.G.
        The Anthropology of Modern Human Teeth.
        Cambridge University Press, Cambridge, UK1997
        • Velmurugan N.
        • Sandhya R.
        Root canal morphology of mandibular first premolars in an Indian population:a laboratory study.
        Int Endod J. 2009; 42: 54-58
        • Baisden M.K.
        • Kulild J.C.
        • Weller R.N.
        Root canal configuration of the mandibular first premolar.
        J Endod. 1992; 18: 505-508
        • Sikri V.K.
        • Sikri P.
        Mandibular premolars: aberrations in pulp space morphology.
        Indian J Dent Res. 1994; 5: 9-14
        • Manning S.A.
        Root canal anatomy of mandibular second molars. Part II. C-shaped canals.
        Int Endod J. 1990; 23: 40-45
        • Jafarzadeh H.
        • Wu Y.
        The C-shaped root canal configuration: a review.
        J Endod. 2007; 33: 517-523
        • Fan B.
        • Cheung G.S.
        • Fan M.
        • et al.
        C-shaped canal system in mandibular second molars: part I—anatomical features.
        J Endod. 2004; 30: 899-903
        • Gao Y.
        • Fan B.
        • Cheung G.S.
        • et al.
        C-shaped canal system in mandibular second molars part IV: 3-D morphological analysis and transverse measurement.
        J Endod. 2006; 32: 1062-1065
        • Jerome C.E.
        C-shaped root canal systems: diagnosis, treatment, and restoration.
        Gen Dent. 1994; 42: 424-427
        • Chai W.L.
        • Thong Y.L.
        Cross-sectional morphology and minimum canal wall widths in C-shaped roots of mandibular molars.
        J Endod. 2004; 30: 509-512
        • Cohen S.
        • Burns R.C.
        Pathways of the Pulp, 8th ed.
        Mosby, St. Louis, MO2002 (196–229)
        • Melton D.C.
        • Krell K.V.
        • Fuller M.W.
        Anatomical and histological features of C-shaped canals in mandibular second molars.
        J Endod. 1991; 17: 384-388
        • Lammertyn P.A.
        • Rodrigo S.B.
        • Brunnotto M.
        • et al.
        Furcation grooves of maxillary first premolar, thickness, and dentin structures.
        J Endod. 2009; 35: 814-817
        • Li X.
        • Liu N.
        • Liu N.
        • et al.
        A micro–computed tomography study of the location and curvature of the lingual canal in the mandibular first premolar with two canals originating from a single canal.
        J Endod. 2012; 38: 309-312
        • Gutmann J.L.
        The dentin-root complex: anatomic and biologic considerations in restoring endodontically treated teeth.
        J Prosthet Dent. 1992; 67: 458-467
        • Caputo A.A.
        • Standlee J.P.
        Pins and posts—why, when and how.
        Dent Clin North Am. 1976; 20: 299-311