• 대한치과의사협회지
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• 제55권8호
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• pp.542-555
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• 2017

1. Diagnosis Diagnosis of Crack, Direct pulp capping 2. Access opening Find the calcified canal orifice Removal of dentin shelf Obtaining the MB2 canal (MB2, MB3, DB2) 3. Perforation repair during endodontic treatment 4. Removal of the separated files 5. Open apex treatment 6. Void removal on CWT procedure 7. Re-endodontic treatment Removal of restorative material filled in pulp chamber Post removal Identification and removal of residual gutta-perch 8. Surgical endodontic treatment In each case will overview how to use a dental microscope.

• Applied Microscopy
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• 제23권1호
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• pp.91-108
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• 1993

The relationship of cartilage canals to initial osteogenesis of primary ossification center of developing vertebrae in human fetuses ranging from 50mm to 260mm in crown rump length was studied by light and electron microscopy. The cartiage canals of the thoracic vertebrae were first observed at 60mm fetus. Cartilage canals were identified as vascular channels arising from perichondrium surfaces. A number of cartilage canals were observed around the primary center of ossification at 80mm fetus. At 120mm fetus, cartilage canals of the bodies of vertebra were increased. Eventually the canals were eroded from the main medullary cavity and remained at only peripheral regions of growth cartilage. Superficial, intermediate, and deep canals were identified by the characteristics of cartilage cells. Fibroblasts, undifferentiated mesenchymal cells, and vacuolated macrophages were observed adjacent to the matrix of resting cartilage cells in the superficial canal. Fibroblasts and mesenchymal cells were densely packed at the tip of canal, giving an epithelial appearance to the clustered cell in the intermediate canal. Vacuolated macrophages were in contact with matrix of hypertrophied cartilage. The thick-walled vessels in the intermediate and deep canals consisted of typical endothelial cells, but in the newly formed vessels contained mesenchymal cells and fibroblasts incorporated into the vessel wall. During lengthening of cartilage canal, the matrix of cartilage cells were invaded by newly formed capillaries and vacuolated macrophages. At the deep canal, the lateral wall of the canal terminated in matrix containing calcified cartilage. The mesenchymal cells began to differentiate into osteoblasts adjacent to the calcified matrix. The results indicate that the connective tissue cells within the cartilage canals proliferate and differentiate into osteoblasts at the site of primary ossification center.

• 대한치과의사협회지
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• 제15권8호
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• pp.611-615
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• 1977

The author observed histochemically the nature of the calcified tissue in the rabbit dental pulp, induced by pulpal injection of potassium permanganate. The pulp of rabbit mandibular incisors were exposed and enlarged by a dental hand reamer. The exposed pulps were injected with 0.05ml of 20mM solution of potassium permanganate dissolved in Ringer's solution in experimental tooth. Also the control tooth received a pulpal injection of 0.05ml of Ringer's solution. After pulpal injection, the tooth was plugged with a gutta-percha root canal point. The staining techniques were hematoxylin-eosin stain, van Gieson stain, PAS reaction, toluidine blue stain, alcian blue-hematoxylin stain and colloidal iron-picric acid stain. The results were as follows: 1. The pulp on experimental tooth showed osteodentin-like calcified tissue. Also, in some areas, false denticle-like substance were observed. 2. The central portion of the calcified matrix showed metachromasia in toluidine blue stain had strong staining capacity in alcian blue stain. 3. The peripheral portion of the calcified tissue revealed marked van Gieson positive reaction for collagen. But their staining ability in alcian blue was slight and metachromasia was not appeared.

• Restorative Dentistry and Endodontics
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• 제1권1호
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• pp.26-32
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• 1975

After a vital pulpotomy in dogs' teeth, the responses of the remaining pulp tissue under hydroxides (calcium hydroxide, magnesium hydroxide, aluminium hydroxide and zinc hydroxide) were studied histologically. The class V cavities were prepared on the teeth and the pulp was amputated. Each hydroxide was placed over the amputated tissue and the cavity was sealed with zinc oxide eugenol cement. Animals were sacrificed after 3 days, 1, 2, and 3 weeks following the operation. The teeth were decalcified, sectioned and stained with hematoxylin and eosin. Microscopic examination reveals as follows; 1. Calcium hydroxide: Inflammatory change was seen in the superficial portion of the remaining pulp tissue at the 3rd day and 1st week. The incompleted calicified material began to be deposited from the canal wall at the 2nd week, and the advanced calcified material was seen at the 3rd week. 2. Magnesium hydroxide: Severe inflammatory change was seen in the superficial portion of the remaining pulp from the 3rd day and the 1st week samples. Inflammatory change was decreased at the 2nd week and the slight calcified material was deposited from the root canal at the 3rd week. 3. Aluminium hydroxide: Severe inflammatory changes were seen in the remaining pulp tissue, the blood vessel was dilated, and the odontoblasts were destroyed at the 3rd day and 1st week. The fibrous degeneration spread to the apex at the 2nd week. There was no evidence of newly formed odontoblasts or deposition of calcified material underneath aluminium hydroxide. 4. Zinc hydroxide: The micrscopic picture was destructive. A thick necrotic layer was found under the amputated surface at the 3rd day and 1st week. Granulation tissue formation as well as chronic inflammatory changes extended to the apical area in the pulp tissue. Also there were no sign of odontoblastic formation or calcified material at the 2nd and 3rd week.

• 대한소아치과학회지
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• 제43권2호
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• pp.200-206
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• 2016

상아질, 백악질, 치수를 포함하는 파절로 정의되는 치근파절은 영구치에서 발생하는 외상 중 0.5-7%를 차지하며, 대부분 11-20세군의 상악 전치부에 호발한다. 영구치 치근파절의 처치는 기본적으로 변위된 치관부 파절편을 정복시키고 고정하는 것이다. 60-80%는 치수생활력이 유지되나 치수괴사나 염증성 치근흡수의 징후가 나타난다면 근관치료를 시행하게 되며 대부분에서 치근부 파절편의 치수생활력은 유지되기 때문에 근관치료는 치관부 파절편에 한하여 수행한다. 그러나 치관부 파절편에서 적절한 apical stop을 얻는 것은 어렵다. 의도적 재식술이란 통제된 환경에서 의도적으로 치아를 발거한 후 구강 외에서 치근단 치료를 시행하고 재식립하는 방법으로 완벽한 근관치료와 수복을 목표로 한다. 통상적인 근관치료가 실패한 경우, 기존의 수복물이 존재하거나 석회화된 근관으로 인해 재근관치료가 어려운 경우, 공간적으로 접근이 불가능하여 치근단 수술을 시행하지 못하는 증례에서 의도적 재식술이 계획될 수 있다. 본 증례에서는 이전의 외상으로 인해 석회화된 근관을 보이는 상악 중절치에서 발생한 수평 치근파절을 치료하기 위해 의도적 재식술을 이용하였고 임상적, 기능적으로 만족할만한 결과를 얻었기에 이를 보고하는 바이다.

• Restorative Dentistry and Endodontics
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• 제6권1호
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• pp.51-62
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• 1980

A Scanning Electron Microscope study was conducted to compare the effectiveness of mechanical preparation of the root canal in conjunction with a few number of canal irrigants that have been widely used for canal treatment. The irrigants used in this study were 5% sodium hypochlorite, 3% hydrogen peroxide, 15% EDTA, and 30% hydrochloric acid. The root canals of 84 freshly extracted teeth with single or multi root were conventionally prepared with Hedstroem files. 78 canals were irrigated with normal saline solution following each instrument number and 6 canals were prepared without irrigation. After instrumentation 72 canals were flushed with various irrigants for predetermined length of time as shown on the Table 1. Additional 20 teeth were kept uninstrumented and five of them were immersed in 15% EDTA for 5 minutes, five in 5% sodium hypochlorite for 5 minutes, five in 3% hydrogen peroxide for 20 minutes, and the last five were only rinsed with saline solution. The SEM examination revealed as follows: 1. The canal wall cannot be thoroughly prepared by means of files. 2. No typical structural changes occured on instrumented dentin surface by saline solution, 3% $H_2O_2$, 5% NaOCl, within 5 minutes. 3. 5% NaOCl Solution showed excellent solvent effect to organic substances in uninstrumented canal within 5 minutes and 15% EDTA and 3% $H_2O_2$ showed unsignificant changes. 4. 15% EDTA and 30% HCl dissolved calcified debris and dentin chips that obturated the dentinal tubules and showed patent orifices. 5. 15% EDTA affected on peritubular dentin more readily and showed concavity around dentinal tubules.

• 환경생물
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• 제36권3호
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• pp.319-328
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• 2018

The morphology, anatomy and reproduction (tetra/bisporic and male) of Lithothamnion japonicum Foslie was studied, using holotype material and materials collected from Korea. Lithothamnion japonicum is characterized based on the presence of encrusting, warty to fruticose thallus, branched or unbranched short and cylindrical protuberances, conical shaped spermatangial conceptacles, branched (dendroid) spermatangial systems formed on floor, walls, and roof of conceptacle chamber, cylindrical shaped spermatangial conceptacle canal, 9-10 cell layered spermatangial conceptacle roof, raised tetra/bisporangial conceptacles without rims, flattened tetra/bisporangial conceptacle pore plate, 16-50 pores on each pore plate, 6-8 rosette cells surrounded by each pore, pore canal lining filaments composed of tetra/bisporangial conceptacle roof, and buried senescent tetra/bisporangial conceptacles completely infilled with relatively large and irregularly arranged calcified sterile cells. In this study, we report a new record of Lithothamnion japonicum from Korean coasts.

• Restorative Dentistry and Endodontics
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• 제44권4호
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• pp.38.1-38.8
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• 2019

Navigation of the main root canal and dealing with a dens invaginatus (DI) is a challenging task in clinical practice. Recently, the guided endodontics technique has become an alternative method for accessing root canals, surgical cavities, and calcified root canals without causing iatrogenic damage to tissue. In this case report, the use of the guided endodontics technique for two maxillary lateral incisors with multiple DIs is described. A 16-year-old female patient was referred with the chief complaint of pain and discoloured upper front teeth. Based on clinical and radiographic findings, a diagnosis of pulp necrosis and chronic periapical abscess associated with double DI (Oehler's type II) was established for the upper left lateral maxillary incisor (tooth #22). Root canal treatment and the sealing of double DI with mineral trioxide aggregate was planned for tooth #22. For tooth #12 (Oehler's type II), preventive sealing of the DI was planned. Minimally invasive access to the double DI and the main root canal of tooth #22, and to the DI of tooth #12, was achieved using the guided endodontics technique. This technique can be a valuable tool because it reduces chair-time and, more importantly, the risk of iatrogenic damage to the tooth structure.

• 대한소아치과학회지
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• 제24권3호
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• pp.575-580
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• 1997

It has been reported that the operative treatment for the preservation of tooth having periapical lesion has shown over ninety percent of success whereas in the case where calcified canal is severe, canal is perforated, ledge is formed, tooth restored by post and core and cases where symptoms still exist after treatment, endodontic treatment may not all be the solution in attaining a successful treatment. Thus Apicoectomy would generally be used to prevent the loss of tooth having periapical lesion where treatment prognosis is poorly evaluated by endodontic treatment. In case 1 and 2, endodontic treatment was applied due to unilocular radiolucent lesion in periapical area but the symptoms somehow did not show improvement and therefore operated apicoectomy, and as in case 1, favorable results were attained but as in case 2, yet more observation has to be done. The followings are the results we have concluded : 1. In the process of endodontic treatment, absolute canal obturation has great effect on attaining successful treatment. 2. In cases where endodontic treatment is not highly recommended, for example, tooth having dental pulp and periapical lesion, favorable results can be attained by applying apicoectomy.

• Restorative Dentistry and Endodontics
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• 제44권3호
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• pp.29.1-29.7
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• 2019

Endodontic microsurgery is defined as the treatment performed on the root apices of an infected tooth, which was unresolved with conventional root canal therapy. Recently, the advanced technology in 3-dimensional model reconstruction based on computed tomography such as cone beam computed tomography has opened a new avenue in application of personalized, accurate diagnosis and has been increasingly used in the field of dentistry. Nevertheless, direct intra-oral localization of root apex based on the 3-dimensional information is extremely difficult and significant amount of bone removal is inevitable when freehand surgical procedure was employed. Moreover, gingival flap and alveolar bone fenestration are usually required, which leads to prolonged time of surgery, thereby increasing the chance of trauma as well as the risk of infection. The purpose of this case report is to present endodontic microsurgery using the guide template that can accurately target the position of apex for the treatment of an anterior tooth with calcified canal which was untreatable with conventional root canal therapy and unable to track the position of the apex due to the absence of fistula.