open access
메뉴
open access
메뉴
ISSN : 0376-4672
Objectives: The purpose of this study was to investigate the ratio of 4 root canals and the incidence of Radix Entomolaris in mandibular first molars and find out anatomical difference according to number of roots by analysis of cone-beam CT images in a Korean population. Materials and Methods: Total 142 images containing mandibular first molars were selected from CBCT images taken from 2013 to 2017 at Gangneung-Wonju National University Dental Hospital. After reconstructing the image with reference to the Cemento-enamel junction, the root canals were detected at the bottom of the pulpal floor and the number of roots and root canals were analyzed. Various lengths and MLO-DLO-DBO angle were measured between each canal orifices and the external contour line of the tooth, and the distolingual canal wall thickness was measured. Student t-test was used for statistical significance. Results: Among the total 142 teeth, 4 canals were 42.2% and Radix Entomolaris was 25.3%. As the results of measuring various lengths and the angle, the distolingual canal orifice in Group 2(with Radix Entomolaris) tends to deviate to the lingual side than the mesiolingual canal orifice and to the mesial side than the distobuccal canal orifice. Besides, thickness of the distolingual canal wall in Group 2(with Radix Entomolaris) was significantly thinner than that of Group 1 at every level except pulpal floor level. Conclusion: It is necessary to consider the difference according to the presence of Radix Entomolaris in endodontic treatment.
Carlsen O, Alexandersen V. Radix paramolaris in permanent mandibular molars: identification and morphology. Scan J Dent Res. 1991;99:189-95.
Curzon ME. Three-rooted mandibular permanent molars in English Caucasians. J Dent Res. 1973;52:181.
Barker BC, Parson KC, Mills PR, Williams GL. Anatomy of root canals. III. Permanent mandibular molars. Aust Dent J. 1974;19:403-13.
Vertucci FJ. Root canal anatomy. Oral Surg Oral Med Oral Pathol. 1984;58:589-99.
Calberson FL, De Moor RJ, Deroose CA. The Radix Entomolaris and Paramolaris: Clinical Approach in Endodontics, J Endod. 2007;33:58-63.
Krasner P, Rankow HJ. Anatomy of the pulpchamber floor. J Endod. 2004;30:5-16.
Plotino G, Tocci L, Grande NM, Testarelli L, Messineo D, Ciotti M, Glassman G, D'ambrosio F, Gambarini G. Symmetry of Root and Root Canal Morphology of Maxillary and Mandibular Molars in a White Population: A Cone-beam Computed Tomography Study In Vivo, J Endod. 2013;39:1545-48.
Jang JK, Peters OA, Lee W, Son SA, Park JK, Kim HC. Kim Y. Incidence of three roots and/or four root canals in the permanent mandibular first molars in a Korean sub-population. Clin Oral Investig. 2013;17:105-11.
Kim SY, Kim BS, Woo J, Kim Y. Morphology of Mandibular First Molars Analyzed by Cone-beam Computed Tomography in a Korean Population:Variations in the Number of Roots and Canals. J Endod. 2013;39:1516-21.
Zhang R, Wang H, Tian YY, Yu X, Hu T, Dummer PM. Use of cone-beam computed tomography to evaluate root and canal morphology of mandibular molars in Chinese individuals, Int Endod J. 2011;44:990-9.
Wang Y, Zheng QH, Zhou XD, Tang L, Wang Q, Zheng GN, Huang DM. Evaluation of the root and canal morphology of mandibular first permanent molars in a western Chinese population by conebeam computed tomography. J Endod. 2010;36:1786-9.
Huang CC, Chang YC, Chuang MC, Lai TM, Lai JY, Lee BS, Lin CP. Evaluation of Root and Canal Systems of Mandibular First Molars in Taiwanese Individuals Using Cone-beam Computed Tomography, J Formosan Ass. 2010;109:303-8.
Carlsen O, Alexandersen V. Radix entomolaris:identification and morphology. Scan J Dent Res. 1990;98:363-73.
De Moor RJ, Deroose CA, Calberson FL. The radix entomolaris in mandibular first molars: an endodontic challenge. Int Endod J. 2004;37:789-99.
Sperber GH, Moreau JL. Study of the number of roots and canals in Senegalese first permanent mandibular molars. Int Endod J. 1998;31:112-6.
Ferraz JA, Pecora JD. Three-rooted mandibular molars in patients of Mongolian, Caucasian and Negro origin. Braz Dent J. 1993;3:113-7.
Reichart PA, Metah D. Three-rooted permanent mandibular first molars in the Thai. Community Dent Oral Epidemiol. 1981;9:191-2.
Turner CG 2nd. Three-rooted mandibular first permanent molars and the question of Am Indian origins. Am J Phys Anthropol. 1971;34:229-41.
Walker T, Quakenbush LE. Three rooted lower first permanent molars in Hong Kong Chinese. Br Dent J. 1985;159:298-9.
Yew SC, Chan K. A retrospective study of endodontically treated mandibular first molars in a Chinese population. J Endod. 1993;19:471-3.
Park JB, Kim N, Park S, Kim Y, Ko Y. Evaluation of root anatomy of permanent mandibular premolars and molars in a Korean population with cone-beam computed tomography. Eur J Dent. 2013;7:94-101.
Song JS, Choi HJ, Jung IY, Jung HS, Kim SO. The prevalence and morphologic classification of distolingual roots in the mandibular molars in a Korean population. J Endod. 2010;36:653-7.
Kim Y, Roh BD, Shin Y, Kim BS, Choi YL, Ha A. Morphological Characteristics and Classification of Mandibular First Molars Having 2 Distal Roots or Canals: 3-Dimensional Biometric Analysis Using Cone-beam Computed Tomography in a Korean Population. J Endod. 2018;44:46-50.
Stroner WF, Remeikis NA, Carr GB. Mandibular first molar with three distal canals. Oral Surg. 1984;57:554-7.
Abella F, Patel S, Duran-Sindreu F, Mercade M, Roig M. Mandibular first molars with disto-lingual roots: review and clinical management. Int Endod J. 2012;45:963-78.
Zhang X, Xiong S, Ma Y, Han T, Chen X, Wan F, Lu Y, Yan S, Wang Y. A Cone-Beam Computed Tomographic Study on Mandibular First Molars in a Chinese Subpopulation. PLoS One. 20154;10:e0134919.
Souza-Flamini LE, Leoni GB, Chaves JF, Versiani MA, Cruz-Filho AM, Pecora JD, Sousa-Neto MD. The radix entomolaris and paramolaris: a microcomputed tomographic study of 3-rooted mandibular first molars. J Endod. 2014;40:1616-21.
Deutsch AS, Musikant BL, Gu S, Isidro M. Morphological measurements of anatomic landmarks in pulp chambers of human maxillary furcated bicuspids. J Endod. 2005;31:570-3.
Garg AK, Tewari RK, Kumar A, Hashmi SH, Agrawal N, Mishra SK. Prevalence of Three-rooted Mandibular Permanent First Molars among the Indian Population, J Endod. 2010;36:1302-6.
Curzon MEJ, Curzon AJ. Three-rooted mandibular molars in the Keewatin Eskimo. J Can Dent Assoc. 1971;37:71-72.
Matherne RP, Angelopoulos C, Kulild JC, Tira D. Use of Cone-Beam Computed Tomography to Identify Root Canal Systems In Vitro, J Endod. 2008;34:87-89.
Wang Q, Yu G, Zhou XD, Peters OA, Zheng QH, Huang DM. Evaluation of X-Ray Projection Angulation for Successful Radix Entomolaris Diagnosis in Mandibular First Molars In Vitro, J Endod. 2011;37:1063-8.