• Journal of Periodontal and Implant Science
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• 제47권1호
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• pp.41-50
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• 2017

Purpose: The aims of the present study were to compare the image quality and visibility of tooth cracks between conventional methods and swept-source optical coherence tomography (SS-OCT) and to develop an automatic detection technique for tooth cracks by SS-OCT imaging. Methods: We evaluated SS-OCT with a near-infrared wavelength centered at 1,310 nm over a spectral bandwidth of 100 nm at a rate of 50 kHz as a new diagnostic tool for the detection of tooth cracks. The reliability of the SS-OCT images was verified by comparing the crack lines with those detected using conventional methods. After performing preprocessing of the obtained SS-OCT images to emphasize cracks, an algorithm was developed and verified to detect tooth cracks automatically. Results: The detection capability of SS-OCT was superior or comparable to that of trans-illumination, which did not discriminate among the cracks according to depth. Other conventional methods for the detection of tooth cracks did not sense initial cracks with a width of less than $100{\mu}m$. However, SS-OCT detected cracks of all sizes, ranging from craze lines to split teeth, and the crack lines were automatically detected in images using the Hough transform. Conclusions: We were able to distinguish structural cracks, craze lines, and split lines in tooth cracks using SS-OCT images, and to automatically detect the position of various cracks in the OCT images. Therefore, the detection capability of SS-OCT images provides a useful diagnostic tool for cracked tooth syndrome.

• Restorative Dentistry and Endodontics
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• 제8권1호
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• pp.45-51
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• 1982

An endodontically treated tooth is likely to be brittle than a vital tooth. Internal structure of the tooth has been weakened due to a significant removal of dentin by coronal access, canal preparation. There are many controversies concerning with various methods of reinforcing an intact anterior tooth that has endodontic treatment. In this experiment, 128 extracted maxillary anterior teeth were endodontically treated, and prepared with 4 methods of restorations; Composite resin filling with zinc phosphate cement, composite resin filling without zinc phosphate cement, composite resin filling with post, and metal crown with post. An Instron testing machine was used to measure the fracture loads of the specimens. The means of the failure loads for the 4 groups were compared by F-test statistically and the failure modes were observed. The results were as follows; 1. There were no statistically significant difference between the failure loads of the four methods of restoration. 2. Teeth without post were fractured in a horizontal or oblique plane through upper or middle third of the root. 3. In the posted teeth, fractures were occurred around the post. 4. In the metal crowned teeth with post, the fracture were occurred around the post or coronal area.

• Restorative Dentistry and Endodontics
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• 제42권3호
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• pp.157-167
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• 2017

This systematic review aims to summarize the current clinical studies that investigated survival rates against fracture of endodontically treated posterior teeth restored with crowns or resin composite restorations. Literature search were performed using keywords. Publications from 1980 to 2016 were searched in PubMed, ScienceDirect, ISI Web of SCIENCE, MEDLINE, and SCOPUS. Included studies were selected based on inclusion and exclusion criteria. Three clinical studies were included: 1 randomized controlled trial and 1 prospective and 1 retrospective cohort studies. Pooled survival rates ranged from 94%-100% and 91.9%-100% for crowns and resin composite, respectively. The majority of teeth had no more than 3 surface loss of tooth structure. The studies included were heterogeneous, and were not appropriate for further meta-analysis. Current evidence suggested that the survival rates against the fracture of endodontically treated posterior teeth restored with crowns or resin composites were not significantly different in the teeth with minimum to moderate loss of tooth structure.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권3호
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• pp.135-139
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• 2014

This following case report describes the open reduction, internal fixation and the reconstruction of an extensive comminuted mandibular fracture with bilateral condylar fractures in a 19-year-old male patient with an intellectual disability and autistic disorder. He suffered fall trauma, resulting in shattered bony fragments of the alveolus and mandibular body between both mandibular rami, the fracture of both condyles and the avulsion or dislocation of every posterior tooth of the mandible. The patient underwent open reduction and internal fixation between both mandibular rami using a reconstruction plate, open reduction and internal fixation of the shattered fragments using miniplates and screws, and the closed reduction of the bilateral condylar fractures.

• Imaging Science in Dentistry
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• 제34권4호
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• pp.185-190
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• 2004

Purpose: To compare the diagnostic accuracy for the detection of root fractures in CMOS-based digital periapical images with conventional film-based periapical images. Materials and Methods: Sixty extracted single-root human teeth with closed apices were prepared endodontically and divided into two groups; artificially induced vertical root fracture group and control group. All radiographs were obtained using the paralleling technique. The radiographs were examined by 4 observers three times within a 4 week interval. Receiver operating characteristic (ROC) analysis was carried out using data obtained from four observers. Intra- and inter-examiner agreements were computed using kappa analysis. Results: The area under the ROC curve (Az) was used as an indicator of the diagnostic accuracy of the imaging system. Az values were as follows: direct-digital images; 0.93, film-based images; 0.92, and inverted digital images; 0.91. There was no significant difference between imaging modalities (P<0.05). The kappa value of inter-observer agreement was 0.42 (range: 0.28-0.60) and intra-observer agreement was 0.57 (range: 0.44-0.75). Conclusion : There is no statistical difference in diagnostic accuracy for the detection of vertical root fractures between digital periapical images and conventional periapical images. The results indicate that the CMOS sensor is a good image detector for the evaluation of vertical root fractures.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권6호
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• pp.513-519
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• 2007

Typical surgical methods for the treatment of mandibular fractures include intermaxillary-fixation (IMF) for obtaining temporary intraoperative occlusion. Traditionally IMF has been achieved with arch-bars or interdental eyelet wiring. However, these techniques are time-consuming procedures, can produce periodontal damage, and are not well tolerated by the patient even under local anesthesia. Moreover, daily maintenance of oral hygiene is difficult for patients with an arch bar. Recently, intermaxillary fixation using intraoral skeletal anchorage screws (SAS) has been introduced for the treatment of mandibular fractures. This method solves the problems above, but they have the potential for tooth damage, screw fractures and intraoperative occlusal instability. In this study, patients with mandiblular fractures were divided into three groups. Group 1 was treated by IMF using archbars(both maxilla and mandible), Group 2 was treated with SAS(maxilla) and arch-bar (mandible), Group 3 was treated with SAS(both maxilla and mandible). The aim of this study was to evaluate the influence of the different IMF methods on periodontal tissue health and intraoperative occlusal rehabilitation about each groups, and to discuss the most favorable IMF method.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권4호
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• pp.712-717
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• 1996

The term osteomyelitis literally means inflammation of bone marrow. It is described as an inflammatory condition of bone primarily engaging the medullary cavity extending to the periosteum. Following circulatory collapse and ischemia, the involved portions of the bone become necrotic. Cellulitis and osteomyelitis are the most frequent complications of fractures of the mandible and maxilla, because there is an abscessed tooth in the line of fracture. Since most fractures are compound fractures, infection may develop because of contact with oral secretions or outside air. The treatment of chronic osteomyelitis is still under debate. Some authors rely on antibiotics alone, while others advocate combination with surgery. But when infection occurs, establish proper drainage and administer antibiotics. Author treated a case of infected mandibular fracture with mandibular osteotomy, sequestrectomy, iliac bone graft and hyperbaric oxygen therapy, who had suffered suppurative osteomyelitis and mandibular nonunion following the open reduction of the mandibular fracture.

• 대한치과의사협회지
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• 제54권8호
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• pp.658-665
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• 2016

Treatment of immature permanent teeth with irreversibly damaged pulp has been challenging in dental practice because of the lack of apical constriction, thin dentinal walls, and short roots. This may lead to the extrusion of filling materials, and fracture of the root due to its more fragile feature during shaping of the root canal. Apexification with calcium hydroxide or MTA is one of the treatment options for these cases. Although favorable results of apexification have been reported, these treatment procedures do not guarantee the increase of root length and/or width even after a long term period. Thus, treated teeth are still prone to fractures. Recently, pulp revascularization has been proposed as an alternative treatment for immature teeth with necrotic pulp and periapical pathosis. Pulp revascularization allows the stimulation of the apical development and the root maturation. There have been many treatment protocols using various materials such as antibiotics and calcium hydroxide medicament. In this case report, literature review about pulp revascularization and two related cases are presented.

• 구강생물연구
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• 제42권4호
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• pp.248-253
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• 2018

Cemental tears are uncommon form of root fracture that can lead to rapid localized periodontal attachment loss. Studies have described periodontal breakdown as being associated with the separation of the cementum from the underlying tooth structure. The aim of this case report is to assess the outcome of treatment of cemental tear with several surgical treatment regimens. Three patients with cemental tear were treated with different surgical method. In all three cases, the cemental tear occurred on maxillary right central incisors. In each case, the root fragment were removed, the localized defect was treated using different surgical methods including guided tissue regeneration and bone graft followed by scaling and root planting. In all three cases, symptoms subsided after the treatment and clinical attachment level was improved up to 2 mm at 3 month after surgery. Both conventional and regenerative periodontal surgery could achieve successful outcomes.

• 대한치과보철학회지
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• 제38권3호
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• pp.366-374
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• 2000

FRC/ceromer system provides the clinician with a durable, flexible, and esthetic alternative to conventional porcelain fused to metal crowns. FRC is the matrix which is silica-coated and embedded in a resin matrix. The ceromer material which is a second generation indirect composite resin contains silanized, microhybrid inorganic fillers embedded in a light-curing organic matrix. FRC/ceromer restoration has a several advantages: better shock absorption, less wear of occluding teeth, translucency, color stability, bonding ability to dental hard tissues, and resiliency. It has versatility of use including inlay, onlay, single crown, and esthetic veneers. With adhesive technique, it can be used for single tooth replacement in forms of inlay adhesion bridge. In single tooth missing case, conventional PFM bridge has been used for esthetic restoration. However, this restoration has several disadvantages such as high cost, potential framework distortion during fabrication, and difficulty in repairing fractures. Inlay adhesion bridge with FRC/ceromer would be a good alternative treatment plan. This article describes a cases restored with Targis/Vectris inlay adhesion bridge. Tooth preparation guide, fabrication procedure, and cementation procedure of this system will be dealt. The strength/weakness of this restoration will be mentioned, also. If it has been used appropriately in carefully selected case, it can satisfy not only dentist's demand of sparing dental hard tissue but also patient's desire of seeking a esthetic restorations with a natural appearance.