• Journal of the Korean Academy of Esthetic Dentistry
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• v.22 no.1
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• pp.47-55
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• 2013

There have been a great number of developments in clinical techniques and dental materials in dentistry to date. Looking at these developments, while it could be seen that functional elements such as mastication were prioritized rather than aesthetic aspect in the past, aesthetic needs of patients have steadily increased over time and accordingly the aesthetic has become considered a priority in the development of dentistry. Although the first to be considered in discussing the aesthetic in clinical dentistry will be the white aesthetic that is the tooth part of prosthesis, the pink aesthetic that refers to the harmony of such prosthesis with gingiva can be an important consideration not to be ignored aesthetically. However, the harmony with the gingiva often cannot be obtained only by the beautiful prosthesis, and in particular, the pontic and implant areas have poor conditions to achieve the gingival (pink) aesthetic due to the absorption of alveolar ridge compared to natural teeth. Among the most important elements of the gingival aesthetic are the gingival level and the interproximal papilla height. It is very difficult to make the gingival aesthetic in the case of insufficient alveolar ridge, and the recovery of ridge volume and contour is necessary in order to overcome this condition. To this end, the most widely used method is the "connective tissue graft". Many techniques of the connective tissue graft have already been introduced for the ridge augmentation, and each technique has different purposes, and advantages and disadvantages. Rather, due to the excessive amount of techniques, there is confusion about selecting the right technique at a certain time. However, the goal is clear. Ways to increase the success rates must be found, and at the same time, a more favorable way to the gingival aesthetic is to be chosen. Thus, in this study, considerations for the gingival aesthetic that makes harmony and the techniques to achieve it are discussed.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.36-44
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• 1999

No one really doubts that the hottest area of dentistry in 21st century would most likely be 'implant'. With the support of a vast amount of research, implant has been successfully and rapidly absorbed into the field of general dentistry including private practitioners. For teeth with hopeless(or refractory) periodontitis or periapical pathosis, with no hesitation most dentists would think extraction as the sole treatment option followed by prosthodontic replacement possibly including implant. Not many dentists would take Trasplantation/Replantation as another treatment option for a particular condition. Dentistry is often more focused on 'Restoration' than 'Preservation' of natural dentition. 'Biologic Implant' is obviously much closer to the concept of 'Preservation'. Many different types of biologic implant system have been introduced to clinical dentistry so far. Many of those have failed to earn reasonable acknowledgement despite of the clinical success they brought. For some reason biologic implant has rather been alienated for long time. RPI(Ring Pin Implant) is designed to improve the prognosis and success rate of transplanted/replanted teeth. RPI is a Ti-based custom made implant system. It is fabricated either by electric casting or milling process. The major feature RPI gas is the 'ring & hole' structure. The hole should be no less than 1mm diameter to allow bone bridge formation thru it. The ring structure and bone bridge formation creates anti-torque activity, which largely increases the 'initial stability' of the transplanted/replanted teeth. It is also reported that RPI is beneficial in the aspect of resisting root resorption following replantation/transplantation procedure.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.29 no.1
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• pp.54-61
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• 2020

Forced orthodontic eruption(FOE) is a non-surgical treatment approach that allows augmenting both soft- and hard-tissue profiles of potential implant sites, by forced orthodontic extrusion of "hopeless" teeth and their periodontal apparatus. By stretching the gingival and periodontal ligament fibers during extrusion, tension is imparted to the entire alveolar socket, stimulating osseous apposition at the alveolar crest. FOE increases the width of the attached gingiva, and the mucogingival junction remains stable when the gingival margin migrates coronally. Based on these effects, FOE of non-restorable teeth prior to implant placement is a viable alternative to conventional surgical augmentative procedures in implant site development. The aim of this case report is to describes coronal soft-tissue augmentation around fractured teeth, which was achieved by FOE before implant placement.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.168-174
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• 2022

In case of gingival recession or bone defect in maxillary anterior implant treatment, it is not easy to obtain satisfactory clinical results. In this case, loss of the labial alveolar plate was diagnosed in the maxillary right central incisor, so after tooth extraction, soft tissue was secured and implant placement with bone graft was planned. In addition, digital guide surgery was performed for the ideal implant position, and GBR (Guided Bone Regeneration) was accompanied with the xenogeneic bone and the autologous bone collected from the mandibular ramus since alveolar bone defects were extensive. After a sufficient period of osseointegration of the implant, a temporary prosthesis was fabricated through secondary stage surgery and impression taking, and through periodic external adjustment, the shape of soft tissue was improved. In the final prosthesis fabrication, a color tone of natural teeth was induced by an gold anodized customized abutment, and an aesthetic and functional zirconia prosthesis with reproducing the shape of the temporary prosthesis through intraoral scan was delivered.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.46-54
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• 2024

Purpose: The purpose of this study was to compare the periodontal status of end-stage renal disease patients undergoing dialysis and referred for intraoral evaluation prior to renal transplantation surgery with those having normal kidney function. Materials and Methods: Patients who had been undergoing dialysis for end-stage renal disease and been referred to the Dental Clinic Center by the Department of Nephrology at University Hospital for intraoral evaluation prior to kidney transplantation surgery. For comparison of periodontal status, subjects without abnormalities in kidney function were matched with the patients by age and gender and selected as healthy controls. The patients' age, gender, comorbidities, type of dialysis received, and duration of dialysis were investigated by reference to their medical records, and data on their periodontal status were analyzed via the relevant periodontal records. Results: A total of 102 patients, including 51 dialyzed patients and 51 healthy control group subjects, participated in this study. In the patients with end-stage renal disease undergoing dialysis with periodontal probing depth of 5 mm or more, percentage of sites with clinical attachment level of 4 mm or more, percentage of teeth with bleeding on probing, number of missing teeth, and ratio of moderate to severe periodontitis were all significantly greater than in the healthy controls. Conclusion: The periodontal status of end-stage renal disease patients undergoing dialysis and referred for intraoral evaluation prior to kidney transplantation was worse than that of healthy controls.

• Restorative Dentistry and Endodontics
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• v.35 no.4
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• pp.285-294
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• 2010

The purpose of this study was to evaluate the viability of periodontal ligament cells of rat teeth after low-temperature preservation under high pressure by means of MTT assay, WST-1 assay. 12 teeth of Sprague-Dawley white female rats of 4 week-old were used for each group. Both side of the first and second maxillary molars were extracted as atraumatically as possible under tiletamine anesthesia. The experimental groups were group 1 (Immediate extraction), group 2 (Slow freezing under pressure of 3 MPa), group 3 (Slow freezing under pressure of 2 MPa), group 4 (Slow freezing under no additional pressure), group 5 (Rapid freezing in liquid nitrogen under pressure of 2 MPa), group 6 (Rapid freezing in liquid nitrogen under no additional pressure), group 7 (low-temperature preservation at $0^{\circ}C$ under pressure of 2 MPa), group 8 (low-temperature preservation at $0^{\circ}C$ under no additional pressure), group 9 (low-temperature preservation at $-5^{\circ}C$ under pressure of 90 MPa). F-medium and 10% DMSO were used as preservation medium and cryo-protectant. For cryo-preservation groups, thawing was performed in $37^{\circ}C$ water bath, then MTT assay, WST-1 assay were processed. One way ANOVA and Tukey HSD method were performed at the 95% level of confidence. The values of optical density obtained by MTT assay and WST-1 were divided by the values of eosin staining for tissue volume standardization. In both MTT and WST-1 assay, group 7 ($0^{\circ}C$/2 MPa) showed higher viability of periodontal ligament cells than other group (2-6, 8) and this was statistically significant (p < 0.05), but showed lower viability than group 1, immediate extraction group (no statistical significance). By the results of this study, low-temperature preservation at $0^{\circ}C$ under pressure of 2 MPa suggest the possibility for long term preservation of teeth.

• Restorative Dentistry and Endodontics
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• v.34 no.4
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• pp.356-363
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• 2009

The purpose of this study was to evaluate the viability of periodontal ligament cells in rat teeth using slow cryo-preservation method under pressure by means of MTT assay and WST-1 assay. Eighteen teeth of Sprague-Dawley white female rats of 4 week-old were used for each group. Both sides of the first and second maxillary molars were extracted as atraumatically as possible under Tiletamine anesthesia. The experimental groups were group 1 (Immediate control), group 2 (Cold preservation at $4^{\circ}C$for 1 week), group 3 (Slow freezing), group 4 (Slow freezing under pressure of 3 MPa). F-medium and 10% DMSO were used as preservation medium and cryo-protectant. For cryo-preservation groups, thawing was performed in $37^{\circ}C$water bath, then MTT assay and WST-1 assay were processed. One way ANOVA and Tukey method were performed at the 95% level of confidence. The values of optical density obtained by MTT assay and WST-1 were divided by the values of eosin staining for tissue volume standardization. In both MTT and WST-1 assay, group 4 showed significantly higher viability of periodontal ligament cells than group 2 and 3 (p < 0.05), but showed lower viability than immediate control group. By the results of this study, slow cryo-preservation method under pressure suggests the possibility for long term cryo-preservation of the teeth.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.1025-1033
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• 2019

Although magnetic resonance imaging without linear hardening of CT is recognized as a method of obtaining high contrast of tissue and excellent resolution image in brain disease and head and neck examination, magnetic susceptibility artifact is generated in case of metal implants in the oral cavity, which is an obstacle to image diagnosis. Therefore, an effort was made in this thesis to find a method to reduce artifacts caused by dental implants and prosthesis in MRI. Implant-induced artifacts in magnetic resonance imaging showed that the signal size increased with shorter TE in GE technique and was inconsistent with water temperature change. In SE technique as well, the signal size of water was generally higher than that of air, but the signal to noise ratio (SNR) was not different by air and temperature. In EPI technique, images with fewer artifacts were obtained quantitatively and qualitatively when there was more water than air, and the signal to noise ratio was measured the highest, especially at water temperatures of 20° and 30°. In conclusion, when examining using the EPI technique rather than the SE or the GE technique, obtaining brain diffusion using a 20° and 30° water bag reduces the magnetic susceptibility artifacts caused by implants and prosthesis, suggesting that it may provide images with high diagnostic value.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.757-765
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• 2008

Maxillary central incisor impactions occur infrequently. Their origins include various local causes, such as odontoma, supernumerary teeth, space loss, and disturbances in the eruption path, also trauma and apical follicular cysts. Impacted teeth can cause serious dental and aesthetic difficulties as well as psychological problems especially in anterior regions. Although the impaction of maxillary incisor occurs less frequently than that of the maxillary canine, it is of concern to parents during the early mixed dentition stage because of the uneruption of the tooth. Forced eruption of impacted teeth should be considered in young patients because this technique can lead to suitable results from a periodontal, occlusal, and esthetic perspective at an earlier stage better than with other treatment options. This report presents the surgical and orthodontic treatment of cases with horizontally impacted and dilacerated maxillary central incisors. For each patient, we used the closed eruption method, placed an attachment on the impacted tooth on surgery, and fully closed the flap. Traction was applied immediately. The impacted tooth erupts through the healed tissue in a manner resembling normal eruption.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.3
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• pp.253-268
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• 2012

Full-mouth reconstruction of a patient using dental implants is a challenge if there is vertical and horizontal bone resorption, since this includes the gingival area and restricts the position of the implants. however, hard- and soft-tissue grafting may allow the implants to be placed into the desired position. Although it is possible to regenerate lost tissues, an alternative is to use fixed detachable prostheses that restore the function and the esthetics of the gingiva and teeth. Various material combinations including metal/acrylic, metal/ceramic, and zirconia/ceramic have been used for constructing this type of restoration. Other problems include wear, separation or fracture of the resin teeth from the metal/acrylic prosthesis, chipping or fracture of porcelain from the metal/ceramic or zirconia/ceramic prosthesis, and fracture of the framework in some free-end prostheses. With virtually unbreakable, chip-proof, life-like nature, monolithic zirconia frameworks can prospectively replace other framework materials. This clinical report describes the restoration of a patient with complete fixed detachable maxillary and mandibular prostheses made of monolithic zirconia with dental implants. The occluding surfaces were made of monolithic zirconia, to decrease the risk of chipping or fracture. The prostheses were esthetically pleasing, and no clinical complications have been reported after two years.