• The Journal of Advanced Prosthodontics
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• 제2권2호
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• pp.46-49
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• 2010

BACKGROUND. Though implant dentistry is very successful and predictable in treatment of patients with destroyed dentition, there are some cases with limitations to implant therapy. In these cases, alternative treatment modality should be considered. CASE DESCRIPTION. A patient with destroyed dentition was rehabilitated with a lateral rotational path removable partial denture. According to the diagnosis, we determined to raise vertical dimension for esthetic and functional restoration. The final restoration was performed after four months of provisional period. CLINICAL IMPLICATION. The edentulous patients with compromised esthetics and functions can be successfully treated with a rotational path removable partial denture through adequate treatment planning and precise laboratory procedure.

• 대한치과교정학회지
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• 제46권1호
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• pp.42-54
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• 2016

The aim of this clinical report is to describe the complex treatment of an adult Class III malocclusion patient who was disappointed with the outcome of a previous oral rehabilitation. Interdisciplinary treatment planning was performed with a primary indication for implant removal because of marginal bone loss and gingival recession, followed by orthodontic and surgical procedures to correct the esthetics and skeletal malocclusion. The comprehensive treatment approach included: (1) implant removal in the area of the central incisors; (2) combined orthodontic decompensation with mesial displacement and forced extrusion of the lateral incisors; (3) extraction of the lateral incisors and placement of new implants corresponding to the central incisors, which received provisional crowns; (4) orthognathic surgery for maxillary advancement to improve occlusal and facial relationships; and finally, (5) orthodontic refinement followed by definitive prosthetic rehabilitation of the maxillary central incisors and reshaping of the adjacent teeth. At the three-year follow-up, clinical and radiographic examinations showed successful replacement of the central incisors and improved skeletal and esthetic appearances. Moreover, a Class II molar relationship was obtained with an ideal overbite, overjet, and intercuspation. In conclusion, we report the successful esthetic anterior rehabilitation of a complex case in which interdisciplinary treatment planning improved facial harmony, provided gingival architecture with sufficient width and thickness, and improved smile esthetics, resulting in enhanced patient comfort and satisfaction. This clinical case report might be useful to improve facial esthetics and occlusion in patients with dentoalveolar and skeletal defects.

• The Journal of Advanced Prosthodontics
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• 제8권3호
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• pp.235-240
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• 2016

PURPOSE. In this study, the aim of this study was to evaluate the effect of implant surface treatment on cell differentiation of osteoblast cells. For this purpose, three surfaces were compared: (1) a modified SLA (MSLA: sand-blasted with large grit, acid-etched, and immersed in 0.9% NaCl), (2) a laser treatment (LT: laser treatment) titanium surface and (3) a laser and acid-treated (LAT: laser treatment, acid-etched) titanium surface. MATERIALS AND METHODS. The MSLA surfaces were considered as the control group, and LT and LAT surfaces as test groups. Alkaline phosphatase expression (ALP) was used to quantify osteoblastic differentiation of MC3T3-E1 cell. Surface roughness was evaluated by a contact profilometer (URFPAK-SV; Mitutoyo, Kawasaki, Japan) and characterized by two parameters: mean roughness (Ra) and maximum peak-to-valley height (Rt). RESULTS. Scanning electron microscope revealed that MSLA (control group) surface was not as rough as LT, LAT surface (test groups). Alkaline phosphatase expression, the measure of osteoblastic differentiation, and total ALP expression by surface-adherent cells were found to be highest at 21 days for all three surfaces tested (P<.05). Furthermore, ALP expression levels of MSLA and LAT surfaces were significantly higher than expression levels of LT surface-adherent cells at 7, 14, and 21 days, respectively (P<.05). However, ALP expression levels between MSLA and LAT surface were equal at 7, 14, and 21 days (P>.05). CONCLUSION. This study suggested that MSLA and LAT surfaces exhibited more favorable environment for osteoblast differentiation when compared with LT surface, the results that are important for implant surface modification studies.

• 대한치과보철학회지
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• 제44권5호
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• pp.617-627
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• 2006

Statement of problem: HA has been used as a coating material on Ti implants to improve osteoconductivity. However. it is difficult to form uniform HA coatings on implants with complex surface geometries using a plasma spraying technique. Purpose : To determine if Ti6Al4V sintered porous-surfaced implants coated with HA sol-gel coated and hydrothermal treated would accelerate osseointegration. Materials and Methods : Porous implants which were made by electric discharge were used in this study. Implants were anodized and hydrothermal treatment or HA sol-gel coating was performed. Hydrothermal treatment was conducted by high pressure steam at $300^{\circ}C$ for 2 hours using a autoclave. To make a HA sol, triethyl phosphite and calcium nitrate were diluted and dissolved in anhydrous ethanol and mixed. Then anodized implant were spin-coated with the prepared HA sols and heat treated. Samples were soaked in the Hanks solution with pH 7.4 at $37^{\circ}C$ for 6 weeks. The microstructure of the specimens was observed with a scanning electron microscope (SEM), and the composition of the surface layer was analyzed with an energy dispersive spectroscope (EDS). Results : The scanning electron micrographs of HA sol-gel coated and hydrothermal treated surface did not show any significant change in the size or shape of the pores. After immersion in Hanks' solution the precipitated HA crystals covered macro- and micro-pores The precipitated Ca and P increased in Hanks' solution that surface treatment caused increased activity. Conclusion : This study shows that sol-gel coated HA and hydrothermal treatment significantly enhance the rate of HA formation due to the altered surface chemistry.

• Journal of Periodontal and Implant Science
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• 제47권1호
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• pp.2-12
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• 2017

The aim of this narrative review is to describe treatment options for the posterior regions of the mandible and the maxilla, comparing short implants vs. longer implants in an augmented bone. The dental literature was screened for treatment options enabling the placement of dental implants in posterior sites with a reduced vertical bone height in the maxilla and the mandible. Short dental implants have been increasingly used recently, providing a number of advantages including reduced patient morbidity, shorter treatment time, and lower costs. In the posterior maxilla, sinus elevation procedures were for long considered to be the gold standard using various bone substitute materials and rendering high implant survival rates. More recently, implants were even placed without any further use of bone substitute materials, but the long-term outcomes have yet to be documented. Vertical bone augmentation procedures in the mandible require a relatively high level of surgical skill and allow the placement of standard-length dental implants by the use of autogenous bone blocks. Both treatment options, short dental implants, and standard-length implants in combination with vertical bone augmentation procedures, appear to result in predictable outcomes in terms of implant survival rates. According to recent clinical studies comparing the therapeutic options of short implants vs. long implants in augmented bone, the use of short dental implants leads to a number of advantages for the patients and the clinician.

• 대한치과교정학회지
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• 제38권1호
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• pp.31-40
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• 2008

최근 절대적인 고정원의 등장으로 다른 부작용 없이 구치부 압하 치료를 가능하게 하였고, 비수술적으로 개방교 합의 심미적인 치료를 가능하게 하였다. 그러나, 이러한 치료법의 장기적인 안정성에 대한 연구는 많이 부족한 실정이다. 이에 본 연구에서는 miniscrew implant 를 이용하여 상악 구치를 압하시켜 치료한 성인 개방교합 환자 11명(남자 1명, 여자 10명) 을 대상으로 치료 전후, 그리고 유지기의 골격성, 치아 치조성 변화를 측모 두부 방사선사진을 이용하여 평가하였으며 계측치의 치료 전후 변화량간의 상관관계와 치료에 의한 변화량과 재발량과의 상관관계를 규명하여 상악구치의 압하를 통해서 개방교합을 치료할 때에 안정성을 평가하였다. 그 결과로 상악 구치는 2.22 mm 압하 (p < 0.001) 가 일어났고, 평균 17.4 개월 유지 후 0.23 mm 의 정출 (p = 0.359) 이 나타났으며, 재발율은 10.36%로 나타났다. 전치부의 수직피개는 평균 5.47 mm 의 증가 (p < 0.01) 가 나타났고 평균 17.4 개월 유지 후 0.99 mm의 감소 (p < 0.05) 가 나타나서, 재발량은 18.10%로 계산되었다. 치료 전후 수치 변화량의 상관분석을 통해 상악 구치 압하량과 하악 평면각 변화량이 상관관계 (p < 0.05) 가 있었다. 치료 전의 개방교합량, 하악 평면각, 전하안면고 경과 치료 후의 수직피개 재발량과는 상관관계가 없었다. 상악 구치 압하량과 수직피개 개선량에서 치료에 의한 변화량과 재발량이 통계적으로 유의한 상관관계를 보였고, 이를 토대로 재발량을 예측할 수 있었다. 이상의 결과를 통하여 성인 개방교합 환자에서 miniscrew implant를 이용한 상악구치부의 압하는 비수술, 심미적 접근방법으로 효율적이고 안정적인 치료방법으로 유용하게 사용할 수 있을 것으로 생각된다.

• Journal of International Society for Simulation Surgery
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• 제1권1호
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• pp.13-15
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• 2014

Nowadays, with advanced 3D printing techniques, the custom-made implant can be manufactured for the patient. Especially in skull reconstruction, it is difficult to design the implant due to complicated geometry. In large defect, an autograft is inappropriate to cover the defect due to donor morbidity. We present the process of manufacturing the 3D custom-made implant for skull reconstruction. There was one patient with skull defect repaired using custom-made 3D titanium implant in the plastic and reconstructive surgery department. The patient had defect of the left parieto-temporal area after craniectomy due to traumatic subdural hematoma. Custom-made 3D titanium implants were manufactured by Medyssey Co., Ltd. using 3D CT data, Mimics software and an EBM (Electron Beam Melting) machine. The engineer and surgeon reviewed several different designs and simulated a mock surgery on 3D skull model. During the operation, the custom-made implant was fit to the defect properly without dead space. The operative site healed without any specific complications. In skull reconstruction, autograft has been the treatment of choice. However, it is not always available and depends on the size of defect and donor morbidity. As 3D printing technique has been advanced, it is useful to manufacture custom-made implant for skull reconstruction.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권2호
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• pp.178-183
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• 2001

Since the introduction of the concept of osseointegration, the success rate of dental implant has increased dramatically. So, the uses of dental implant in the treatment of partially or fully edentulous patients have played an important role in dental rehabilitation. Regardless of high success rate of dental implant, some amounts of fixtures cannot help failing. We can classify dental implant failure according to timing, causative factor, etc. This study is focused on dental implant fixture failure, occurring during preprosthetic stage. There are various reasons that cause implant failure on this periods, such as improper patient selection, poor bone quality, and periimplantitis, etc. We investigate the survival rate of 1058 fixtures, which installed in 306 patients in our clinic from January 1997 to December 1999, according to type, sex, location, fixture length and width, using Kaplan-Meier product-limit method and to compare each other with log-rank test. Overall survival rate was 96.80%, and 33 implants failed over the preprosthetic stage. Our survey data identified posterior location of mandible as being associated with implant failure(P<0.05).

• Journal of Periodontal and Implant Science
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• 제38권4호
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• pp.723-728
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• 2008

Purpose: During guided bone regeneration procedures for the augmentation of deficient alveolar ridge, primary closure of flap is necessary. For primary flap closure, flap is repositioned coronally and the zone of attached keratinized mucosa may decreased. The need for attached keratinized mucosa around dental implants is still controversial, but sufficient peri-implant attached keratinized mucosa would be beneficial for functional and esthetic aspects. This case report presents three cases that demonstrated free gingival graft for increasing the zone of peri-implant attached keratinized mucosa which was decreased after guided bone regeneration. Materials and Methods: In first case, maxillary incisors were extracted and guided bone regeneration was performed simultaneously. Because the membrane was exposed at 3 weeks after operation, the membrane was removed and free gingival graft was performed for primary flap closure. Free gingival graft was performed again at implant placement for the increase of attached keratinized mucosa. In second case, guided bone regeneration was performed on lower right first molar area, and implant was placed with free gingival graft. In third case, lower right molar area showed insufficient attached keratinized mucosa after implant placement with guided bone regeneration. When abutments were connected, free gingival graft with apically positioned flap was performed. Result: In these three cases, the zone of attached keratinized mucosa around dental implants was decreased after guided bone regeneration. And the increase of peri-implant attached keratinized mucosa could be obtained effectively by free gingival graft. Conclusion: Free gingival graft could be a effective treatment method increasing the zone of attached keratinized mucosa which was decreased after guided bone regeneration procedures.

• The Journal of Advanced Prosthodontics
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• 제6권5호
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• pp.361-371
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• 2014

PURPOSE. In case of large horizontal discrepancy of alveolar ridge due to severe resorption, cantilevered crown is usually an unavoidable treatment modality. The purpose of this study was to evaluate the clinical criteria for the placement of the aforementioned implant crown. MATERIALS AND METHODS. The mandible model with 2 mm thick cortical bone and cancellous bone was fabricated from CT cross-section image. An external connection type implant was installed and cantilevered crowns with increasing offset of 3, 4, 5, 6, and 7 mm were connected. Vertical load and $30^{\circ}$ oblique load of 300 N was applied and stress around bone and implant component was analyzed. A total of 14 cases were modeled and finite element analysis was performed using COSMOS Works (Solid works Inc, USA). RESULTS. As for the location of the vertical load, the maximum stress generated on the lingual side of the implant became larger according to the increase of offset distance. When the oblique load was applied at $30^{\circ}$, the maximum stress was generated on the buccal side and its magnitude gradually decreased as the distance of the offset load increased to 5 mm. After that point, the magnitude of implant component's stress increased gradually. CONCLUSION. The results of this study suggest that for the patient with atrophied alveolar ridge following the loss of molar teeth, von-Mises stress on implant components was the lowest under the $30^{\circ}$ oblique load at the 5 mm offset point. Further studies for the various crown height and numbers of occusal points are needed to generalize the conclusion of present study.