• Restorative Dentistry and Endodontics
• /
• 제37권3호
• /
• pp.175-179
• /
• 2012

The aim of this study was to present a method for endodontic management of a maxillary first molar with unusual C-shaped morphology of the buccal root verified by cone-beam computed tomography (CBCT) images. This rare anatomical variation was confirmed using CBCT, and nonsurgical endodontic treatment was performed by meticulous evaluation of the pulpal floor. Posttreatment image revealed 3 independent canals in the buccal root obturated efficiently to the accepted lengths in all 3 canals. Our study describes a unique C-shaped variation of the root canal system in a maxillary first molar, involving the 3 buccal canals. In addition, our study highlights the usefulness of CBCT imaging for accurate diagnosis and management of this unusual canal morphology.

• Restorative Dentistry and Endodontics
• /
• 제32권1호
• /
• pp.37-46
• /
• 2007

C-shape 근관은 주로 하악 제 2대구치에서 보이는 해부학적 변이 형태로서, 그 특징은 각 근관을 연결하는 fin이나 web이 존재한다. 이런 해부학적으로 복잡함은 근관치료시에 세정과 성형 및 근관충전을 방해하며, 과다한 기구 조작시에 뜻하지 않는 천공을 유발하기도 한다. 이 연구의 목적은 C-shape 치근을 가진 하악 제2 대구치의 해부학적인 형태와 치근의 위치에 따른 최소 근관벽 두께에 대하여 연구하고자 하였다. 발거된 하악 대구치중 C-shape 치근을 가진 치아를 30개 선별하여 방사선 사진 및 협측, 설측, 치근단 부위를 디지털 카메라를 이용하여 촬영하였다. 자가 중합형 교정용 레진 (Orthodontics resin, Densply/Caulk, U.S.A)을 이용하여 치관부를 제거한 치아를 매몰한 후 각각의 시편을 Accutom-50 (Struers, Denmark)에 고정시켜 1 mm 간격으로 절단, 연마한 다음 절단면을 수술용현미경에 연결된 디지털 카메라 (Coolpix 995, Nikon, Tokyo, Japan)를 이용하여 각각의 상을 촬영하였다. 30개 치아에서 촬영한 197개의 치아단면을 Root thickness gauge program을 이용하여 근관형태의 변화를 분류하고 부위별 근관과 치아외벽 사이에 존재하는 상아질의 최소두께에 대해 연구 분석하였다. 1. 근관입구에서 C I이 가장 많이 (73%) 관찰되었으나 치근단부로 갈수록 근관 형태의 다양한 변화를 보여 C II와 C III의 근관형태가 많이 관찰되었으며, 11 개의 (36%)치아에서는 근관입구에서 치근단부까지 근관형태의 변화를 보이지 않았다. 근관입구에서 단지 2개의 치아에서 나타난 C III type은 치근단부로 갈수록 높은 발현빈도를 나타내었다. 2. C-shape 근관은 근관입구 부위에서는 continuous 나 semicolon canal을 가지나 치근단부로 갈수록 2개나 3개의 근관을 갖는 경우가 많다. 3.평균적인 근관과 치질사이의 최소거리는 근첨부의 설측부위에서 나타났다.

• 대한치과보철학회지
• /
• 제58권2호
• /
• pp.95-102
• /
• 2020

목적: Cone-beam computed tomographic (CBCT)를 이용하여 한국인의 상악 제1대구치(MM1), 제2대구치(MM2)에서 제2근심협측(MB2) 근관, 치근 융합 및 C형 근관의 발생률에 대해 평가하였다. 재료 및 방법: 술 전 평가를 위해 CBCT 촬영을 한 환자를 선택했다. 1658명의 환자로부터 1498개의 MM1과 1742개의 MM2의 CBCT 영상이 획득되었고, MB2 근관, 치근융합 및 C형 근관을 분석했다. 연령, 성별 및 치아위치와 MB2 근관 발생률간의 관계도 조사하였다. 결과: 연구표본은 비교적 고령(평균연령: 66.1세)이었다. MB2 근관의 발생률은 MM1, MM2 각각 60.1%, 28.0% 였고, MM1, MM2에서 각각 Weine Type III, Type II가 우세했다. 연령이 증가함에 따라 MB2 근관은 감소하는 경향을 보였으며, MM1에서는 남성에서 MB2 근관이 더 많이 발견되었다. 치근융합은 MM1에서 2.3%, MM2에서 26.2%, C형 근관은 MM1에서 0.4%, MM2에서 2.7%로 모두 MM2에서 발생률이 더 높았다. 결론: MB2 근관은 MM2보다 MM1에서 더 발생률이 높았다. 치근융합과 C형 근관은 모두 MM2에서 더 발생률이 높았다.

• Restorative Dentistry and Endodontics
• /
• 제44권2호
• /
• pp.18.1-18.9
• /
• 2019

Objective: This study evaluated the presence of residual root canal filling material after retreatment using micro-computed tomography (micro-CT). Materials and Methods: Extracted human teeth (single- and double-rooted, n = 21/each; C-shaped, n = 15) were prepared with ProFile and randomly assigned to three subgroups for obturation with gutta-percha and three different sealers (EndoSeal MTA, EndoSequence BC sealer, and AH Plus). After 10 days, the filling material was removed and the root canals were instrumented one size up from the previous master apical file size. The teeth were scanned using micro-CT before and after retreatment. The percentage of remaining filling material after retreatment was calculated at the coronal, middle, and apical thirds. Data were analyzed using the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni post hoc correction. Results: The tested sealers showed no significant differences in the percentage of remaining filling material in single- and double-rooted teeth, although EndoSeal MTA showed the highest value in C-shaped roots (p < 0.05). The percentage of remaining filling material of AH Plus and EndoSeal MTA was significantly higher in C-shaped roots than in single- or double-roots (p < 0.05), while that of BC sealer was similar across all root types. EndoSeal MTA showed the highest values at the apical thirds of single- and double-roots (p < 0.05); otherwise, no significant differences were observed among the coronal, middle, and apical thirds. Conclusions: Within the limitations of this study, a large amount of EndoSeal MTA remained after retreatment, especially in C-shaped root canals.

• Journal of Korean Dental Science
• /
• 제14권2호
• /
• pp.61-68
• /
• 2021

Purpose: The aim of this study was to investigate the outcomes of endodontic treatment of mandibular second molar with C-shaped canal in elderly patients and related factors affecting the survival of the tooth. Materials and Methods: From 2010 to 2015, the survival rate following endodontic treatment was evaluated in elderly patients over 60 years who visited the Veterans Health Service Medical Center for endodontic treatment. The presence of C-shaped canals was confirmed using clinical records and radiographic features. Patient's age, sex, systemic diseases, tooth location, vitality, signs and symptoms, fractures, caries, apical radiolucency, canal shaping methods, sealer leakage, filling voids, and restoration of prosthesis were included in the analyses as confounding variables. The survival rate of teeth was analyzed using Kaplan-Meire analysis and the relationship between the survival rate and variables was analyzed using Simple and Multiple Cox regression analysis. Result: In total, 107 teeth in elderly patients had C-shaped canal. The survival rate of teeth that received endodontic treatment was 63.70%. None of the factors investigated significantly influenced the survival rate (P>0.05). Conclusion: In elderly patients with C-shaped canal, the survival rate after root canal treatment was not significantly different from that of other mandibular molars.

• 구강회복응용과학지
• /
• 제32권1호
• /
• pp.32-37
• /
• 2016

목적: Cone beam형 전산화 단층영상(CBCT)을 이용하여 한국인의 하악 제2대구치에서 C형 근관계의 해부학적인 특징을 결정하기 위함이다. 연구 재료 및 방법: 824개의 영상을 평가하였다. 2013년 치과임플란트 진단 및 치료를 위해 CBCT를 찍은 환자를 대상으로 하였다. 711개의 하악 제2대구치가 조사되었다. 근관계의 형태는 변형된 Melton 분류를 이용하여 분류하였다. 결과: 711개의 하악 제2대구치에서 21.5%가 C형 근관계를 가졌다. 이러한 분포는 치아 위치에 따라 달라지지 않았다. 양쪽으로 존재하는 대구치에서 대부분의 C형 근관은 대칭적으로 나타났다. C형 근관에서 가장 흔한 형태는 orifice 부분에서 Melton's Type I (89%), 치근단부위에서는 Melton's Type III (83.8%) 이었다. C형 근관은 남성(13.9%)보다 여성(25%)에서 더 많이 나타났다. 결론: 한국인의 하악 제2대구치에서 C형 근관은 매우 높게 나타난다. 성공적인 C형 근관의 치료를 위해 근관계의 특성을 이해하는 것은 중요하다.

• Restorative Dentistry and Endodontics
• /
• 제43권4호
• /
• pp.42.1-42.7
• /
• 2018

Objectives: The purpose of this study was to investigate the C-shaped root canal anatomy of mandibular second molars in a Korean population. Materials and Methods: A total of 542 teeth were evaluated using cone-beam computed tomography (CBCT). The canal shapes were classified according to a modified version of Melton's method at the level where the pulp chamber floor became discernible. Results: Of the 542 mandibular second molars, 215 (39.8%) had C-shaped canals, 330 (53%) had 3 canals, 17 (3.3%) had 2 canals, 12 (2.2%) had 4 canals, and 8 (1.7%) had 1 canal. The prevalence of C-shaped canals was 47.8% in females and 28.4% in males. Seventy-seven percent of the C-shaped canals showed a bilateral appearance. The prevalence of C-shaped canals showed no difference according to age or tooth position. Most teeth with a C-shaped canal system presented Melton's type II (45.6%) and type III (32.1%) configurations. Conclusions: There was a high prevalence of C-shaped canals in the mandibular second molars of the Korean population studied. CBCT is expected to be useful for endodontic diagnosis and treatment planning of mandibular second molars.

• Restorative Dentistry and Endodontics
• /
• 제27권4호
• /
• pp.421-431
• /
• 2002

C-shaped canal configuration is very difficult to treat because that clues about preoperative canal anatomy cannot be ascertained from clinical crown morphology and limited information can be derived from radiographic examination. This study was done to get more informations about the root and canal configuration of C-shape root by 3-dimensionally reconstructing for the purpose of enhancing success rate of endodontic treatment. 30 mandibular molars with C-shaped root were selected. Six photo images from occlusal, apical, mesial, distal, buccal, lingual directions and radiographic view were taken as preoperative ones to compare them with 3-D image. After crown reduction to the level of 1-2mm over pulpal floor was performed, teeth were stored in 5.25% sodium hypochlorite solution for the removal of pulp tissue and debris. They were cleaned under running water, allowed to bench dry and embedded in a self-curing resin. This resin block was serially ground with a microtome (Accutom-50, Struers, Denmark) and the image of each level was recorded by digital camera (FinePix S1-pro, Fuji Co., Japan). The thickness of each section was 0.25mm. Photographs of serial sections through all root canal were digitized using Adobe Photoshop 5.0 and then minimum thickness of open and closed sites were measured (open site is the surface containing occluso-apical groove closed site is oppsite). After dizitization using 3-D Doctor (Able software Corp, USA). 3D reconstruction of the outer surface of tooth and the inner surface of pulp space was made. Canal classsification of C-shaped roots was performed from this 3-D reconstructed image. The results were as follows : 1. Most C-shape rooted teeth showed lingual groove (28/30). 2 According to Vertuccis' calssification, type I, II, III, IV, VII were observed. but also new canal types suck as 2-3-2, 1-2-3-2. 2-3-2-1, 2-3-2-3 were shown. 3 There was little difference in minimum thickness on coronal and apical portions, but open site were thinner than closed site on mid portion. Conclusively, 3D reconstruction method could make the exact configurations of C-shape root possible to be visualized and analyzed from multi-directions. Data from minimum thickness recommend cleaning and shaping be more carefully done on dangerous mid portion.

• Restorative Dentistry and Endodontics
• /
• 제36권1호
• /
• pp.19-25
• /
• 2011

연구목적: 인류지질학적으로 동양인에게서 많이 발견되는 C-형 근관계를 가진 하악 제2대구치는 근관치료나 비외과적 재치료에 실패하는 경우 외과적 재치료 방법으로 의도적 재식술을 시행하게 되는데 그 성공률에 대한 보고가 없었다. 따라서 본 연구의 목적은 C-형 근관계를 가진 하악 제2대구치에 의도적 재식술을 시행한 환자의 기록을 후향적으로 조사하여 치료 결과에 따른 성공률을 확인할 뿐 아니라 치료전 존재하던 치근단 병소가 성공률에 영향을 미치는 바에 대하여 알아보는 것이다. 연구 재료 및 방법: 연구를 위해 2005년 1월부터 2007년 12월에 걸쳐 서울대학교치과병원 치과보존과에 내원하여 하악 제2대구치에 의도적 재식술을 받은 52명의 환자 기록을 조사하였으며 7개의 치아는 정기적인 내원검진 기록이 없어서 조사 대상에서 제외하였고 다른 6개의 치아는 C-형 근관계의 조건에 해당되지 않아 연구에서 제외하였다. 정기 내원후 시행한 임상 검사와 방사선 사진 기록을 후향적으로 검토하여 성공이나 불완전한 치유 또는 실패등의 치료 결과에 대하여 판단하였다. 결과: C-형 근관계를 가진 29개의 하악 제2대구치에 시행한 의도적 재식술의 성공률은 72.4%로 관찰되었으며 치료전 치근단 병소가 존재한 경우의 성공률은 치근단 병소가 없었던 경우와 유사한 것으로 확인되었다. 결론: 본 연구결과 C-형 근관계를 가진 하악 제2대구치의 근관치료가 실패한 경우 시행하게 되는 의도적 재식술은 술전 병소의 존재 유무에 상관없이 치근단 수술의 성공률과 유사한 결과를 얻을 수 있는 치료라고 사료된다.

• Restorative Dentistry and Endodontics
• /
• 제41권4호
• /
• pp.262-270
• /
• 2016

Objectives: This study aimed to evaluate the healing rate of non-surgical endodontic treatment between C-shaped and non-C-shaped mandibular second molars. Materials and Methods: Clinical records and radiological images of patients who had undergone endodontic treatment on mandibular second molars between 2007 and 2014 were screened. The periapical index scoring system was applied to compare healing outcomes. Information about preoperative and postoperative factors as well as the demographic data of the patients was acquired and evaluated using chi-square and multinomial logistic regression tests. Results: The total healing rate was 68.4%. Healing rates for the mandibular second molar were 70.9% in C-shaped canals (n = 79) and 66.6% in non-C-shaped ones (n = 117). The difference was not statistically significant. Conclusions: The presence of a C-shaped canal in the mandibular second molar did not have a significantly negative effect on healing after treatment. Instead, proper pulpal diagnosis and final restoration were indicated as having significantly greater influence on the healing outcomes of C-shaped and non-C-shaped canals, respectively.