• 대한치과보철학회지
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• 제34권4호
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• pp.833-849
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• 1996

The material of choice for functional and esthetic reconstruction of maxillofacial defects is silicone. Silicone has appropriate physical properties for maxillofacial prosthesis but it has weak edge strength. Therefore, a proper combination of silicone and polyurethane sheet is recommended to improve this weakness. Various primers are also used to enhance the adhesive strength between silicone and polyurethane sheet. The purpose of this study was to determine the adhesive strength of silicone and polyurethane sheet. Silicone elastomer mixture was made by admixing MDX4-4210 elastomer (40%) and Silastic Medical Adhesive Type A(60%). This silicone elastomer mixture was attached to polyurethane sheet, using one of three different primers(1205, S-2260, or A-304), treated for 1, 2, 4, 6, and 8 hours. These were then polymerized in room temperature, dry-heat oven or microwave oven. Six specimens per each group, a total of 270 specimens were prepared for final test. The differences of T-peel bonding strengths were then determined by a test. The differences of T-peel bonding strengths were then determined by a test method that was recommended by American Society for Testing and Materials C794-80. The results were statistically analyzed using the ANOVA and Mutiple Range Tests(Tukey' HSD). The reults were as follow. 1. Type of primer, primer reaction time, and methods of polymerization showed significant correlation on the T-peel bonding strengths in adhesiveness between silicone and polyurethane sheet. 2. A-304 primer showed statistically higher in T-peel bonding strength than otehr type of primers except for the polymerization in microwave oven with reaction times of 2, 6 hours(p<0.05). 3. No significant differences in T-peel bonding strength were observed among the polymerization methods. 4. The effect of reaction time by the primer type and polymerization method showed statistically significant differences in bonding strength among different reaction times. And in most cases, reaction time of 1 or 2 hours showed higher T-peel bonding strength.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제39권
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• pp.13.1-13.8
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• 2017

Background: Oronasal/antral communication, loss of teeth and/or tooth-supporting bone, and facial contour deformity may occur as a consequence of maxillectomy for cancer. As a result, speaking, chewing, swallowing, and appearance are variably affected. The restoration is focused on rebuilding the oronasal wall, using either flaps (local or free) for primary closure, either prosthetic obturator. Postoperative radiotherapy surely postpones every dental procedure aimed to set fixed devices, often makes it difficult and risky, even unfeasible. Regular prosthesis, tooth-bearing obturator, and endosseous implants (in native and/or transplanted bone) are used in order to complete dental rehabilitation. Zygomatic implantology (ZI) is a valid, usually delayed, multi-staged procedure, either after having primarily closed the oronasal/antral communication or after left it untreated or amended with obturator. The present paper is an early report of a relatively new, one-stage approach for rehabilitation of patients after tumour resection, with palatal repair with loco-regional flaps and zygomatic implant insertion: supposed advantages are concentration of surgical procedures, reduced time of rehabilitation, and lowered patient discomfort. Cases presentation: We report three patients who underwent alveolo-maxillary resection for cancer and had the resulting oroantral communication directly closed with loco-regional flaps. Simultaneous zygomatic implant insertion was added, in view of granting the optimal dental rehabilitation. Conclusions: All surgical procedures were successful in terms of oroantral separation and implant survival. One patient had the fixed dental restoration just after 3 months, and the others had to receive postoperative radiotherapy; thus, rehabilitation timing was longer, as expected. We think this approach could improve the outcome in selected patients.

• 대한치과의사협회지
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• 제56권11호
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• pp.605-614
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• 2018

PURPOSE. The purpose of this study is to determine the efficacy of the DENTIS submerged-type implant with an internal hex connection and to build corresponding abutment-selection criteria. MATERIAL AND METHODS. A total of 204 patients received submerged implant fixtures with an internal hex connection at the Dong-A University Hospital Dental clinic in Busan from January 2013 and May 2016. Three specific abutments, UCLA abutments, customized abutments, ready-made abutments, were randomly selected. Implant success was defined as the basis of the International Congress of Oral Implantologists(ICOI, 2007) criteria. The relationship between the implant success rate and the abutment factor was analyzed using the Kruskal-Wallis test(P<.05). RESULTS. A total of 508 implants were placed in 204 patients. After a mean observation period of 38.6 months, 493 out of 508 implants were in normal function, yielding an overall success rate of 97.05%. A total of 15 implants failed: 10 in the maxillary molar area, 4 in the mandibular molar area, and 1 in the mandibular incisal area. All of the implant failures occurred in a single-implant prosthesis, especially high in the maxillary molar area. The Kruskal-Wallis analysis showed that abutment selection has no significant correlation with implant failure(P>.05). CONCLUSION. DENTIS submerged implants with an internal hex connection showed predictable results with a success rate of 97.05%. It is no influence on the success rate in the selection of submerged implant abutment with an internal hex connection.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권5호
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• pp.402-407
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• 2010

Introduction: The planning of implant surgery is an important factor for the implant prosthesis. Stereolithographic (SLA) surgical stents based on a computer simulation are quite helpful for clinicians to perform the surgery as planned. Although many clinical and technical trials have been performed for computed tomography (CT)-guided implant stents to improve the surgical procedures and prosthetic treatment, there are still many problems to solve. We developed a system of a surgical guide based on 3 dimensional (3D) CT for implant therapy and achieved satisfactory results in the terms of planning and operation. Materials and Methods: Fifteen patients were selected and 30 implant fixtures were installed. The preoperative CT data for surgical planning were prepared after obtaining informed consent. Surgical planning was performed using the simulation program, Ondemend3D In2Guide. The stents were fabricated based on the simulation data containing information of the residual bone, the location of the nerve, and the expected design of the prostheses. After surgery with these customized stents, the accuracy and reproducibility of implant surgery were evaluated based on the computer simulation. The data of postoperative CT were used to confirm this system using the image fusion technique and compare the implant fixtures between the planned and implanted. Results: The mean error was 1.18 (${\pm}0.73$) mm at the occlusal center, 1.23 (${\pm}0.67$) mm at the apical center, and the axis error between the two fixtures was $3.25^{\circ}C$ (${\pm}3.00$). These stents showed superior accuracy in maxilla cases. The lateral side error at the apical center was significantly different from the error at the occlusal center but there were no significant differences between the premolars, 1st molars and 2nd molars. Conclusion: SLA surgical stents based on a computer simulation have the satisfactory accuracy and are expected to be useful for accurate planning and surgery if some errors can be improved.

• 대한치과보철학회지
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• 제55권1호
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• pp.61-70
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• 2017

본 증례에서는 기존의 총의치 사용 환자에서 의치의 이장된 인상면을 스캔하고 이를 삼차원적으로 반전하여 잔존 치조제의 형태를 재현하고, 의치에 방사선 불투과성 마커를 부착한 상태로 스캔 및 CT 촬영을 진행하여 스캔 이미지와 CT 영상이 중첩된 데이터 상에서 임플란트 식립을 계획하였다. 수술 당일에는 치은 형태에 맞게 제작된 맞춤형 지대주와 임시 수복물을 장착하였다. 임플란트 고정체의 골유착이 완료된 이후 최종 보철물을 제작하는 과정에서는 임플란트 식립 전 미리 스캔하여 저장된 임플란트 지대주 이미지 파일과 구강 내 지대주 상태에서 채득된 구강 스캔 이미지를 중첩하였다. 중첩을 통해 얻어진 정확한 지대주 형태 상에서 최종 보철물을 제작함으로써 최종 보철물의 변연 적합도를 높이고 임상 과정을 간소화 할 수 있었다.

• Journal of Korean Dental Science
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• 제6권1호
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• pp.27-33
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• 2013

The introduction of osseointegrated dental implants in dentistry brought about a new era in everyday dental practice. For the past 50 years, prosthetic restoration with implant-supported prosthesis has developed into a viable and predictable treatment option. Alongside the increasing use of dental implants is the occurrence of many complications during implant placement (surgery), in the mechanical or prosthetic problem, and in the biological aspect. In particular, abutment or screw fracture as one of the mechanical complications can put the dentist in a tight spot in a clinical situation. It is hard to remove the fractured abutment and screw to restore it properly. Therefore, it is very important that clinicians consider possible complications in advance and make an appropriate treatment plan. We discuss cases of abutment fracture and mechanical/prosthetic complications together with the causes and solutions.

• The Journal of Advanced Prosthodontics
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• 제3권2호
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• pp.106-109
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• 2011

Oral cancer treatment involves the surgical removal of all or part of the maxilla, leaving the patient with a defect that compromises the integrity and function of the oral cavity. The postoperative restoration of esthetics, deglutition, and speech shortens recovery time in the hospital and expedites the patient's return to the community as a functioning member. The surgical obturator is the proven treatment option in such situations. This article describes a simple technique to fabricate a surgical obturator that restores patient's original dentition and facial and palatal tissue form. The obturator fabricated with this technique utilizes the vacuum formed index of patient's original tissue form and duplicated partly in heat and partly in auto polymerizing acrylic resin. Duplication of the original tissue form helps patient to minimize the immense physiological trauma immediately after the surgical resection. The obturator fabricated with this technique supports soft tissues after surgery and minimizes scar contracture and disfigurement, and thus may have a positive effect on the patients' psychology.

• 대한구순구개열학회지
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• 제8권2호
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• pp.95-105
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• 2005

Cleft lip and palate is a congenital deformity which needs a professional and consistent management from the birth and along with the physical growth of patients. The patients with cleft lip and palate can have general speech problems with resonance disorders, voice disorders and articulation disorders after the successful primary surgical management and the physical growth. Speech problems of Cleft lip and palate are characterized hypernasality, nasal air emission, increased nasal air flow, and aberrant speech marks which decrease intelligibility. These speech problems of cleft lip and palate can be treated with the secondary surgical procedure, the application of temporary prosthesis and the effective and well-timed speech therapy. The speech and language problems of cleft lip and palate, the general procedures and schedules of the speech assessment and therapy based on the multidisciplinary approach are introduced for the patients with cleft lip and palate, their family and the other members of the cleft palate treatment team.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.41.1-41.6
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• 2016

Background: The goal of this study was to retrospectively evaluate the prognosis of minimal invasive horizontal ridge augmentation (MIHRA) technique using small incision and subperiosteal tunneling technique. Methods: This study targeted 25 partially edentulous patients (10 males and 15 females, mean age $48.8{\pm19.7years$) who needed bone graft for installation of the implants due to alveolar bone deficiency. The patients took the radiographic exam, panoramic and periapical view at first visit, and had implant fixture installation surgery. All patients received immediate or delayed implant surgery with bone graft using U-shaped incision and tunneling technique. After an average of 2.8 months, the prosthesis was connected and functioned. The clinical prognosis was recorded by observation of the peri-implant tissue at every visit. A year after restoration, the crestal bone loss around the implant was measured by taking the follow-up radiographs. One patient took 3D-CT before bone graft, after bone graft, and 2 years after restoration to compare and analyze change of alveolar bone width. Results: This study included 25 patients and 39 implants. Thirty eight implants (97.4 %) survived. As for postoperative complications, five patients showed minor infection symptoms, like swelling and tenderness after bone graft. The other one had buccal fenestration, and secondary bone graft was done by the same technique. No complications related with bone graft were found except in these patients. The mean crestal bone loss around the implants was 0.03 mm 1 year after restoration, and this was an adequate clinical prognosis. A patient took 3D-CT after bone graft, and the width of alveolar bone increased 4.32 mm added to 4.6 mm of former alveolar bone width. Two years after bone graft, the width of alveolar bone was 8.13 mm, and this suggested that the resorption rate of bone graft material was 18.29 % during 2 years. Conclusions: The bone graft material retained within a pouch formed using U-shaped incision and tunneling technique resulted with a few complications, and the prognosis of the implants placed above the alveolar bone was adequate.

• 대한치과보철학회지
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• 제55권3호
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• pp.279-285
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• 2017

구강암에 대한 외과적 처치로 구강 내 광범위한 경조직, 연조직을 제거한 환자는 저작, 연하, 발음 등의 기능적 문제와 치열, 안모의 심미적 문제를 갖게 된다. 악골 재건 후에도 치조골 등 합병증으로 인해 가철성 보철물의 유지 및 지지를 받는데 제한적이다. 임플란트 지지 고정성 보철물은 이러한 환자들에게 적절한 보철수복 방법이 되어 왔다. 본 증례는 하악 재건 후 computer-aided design과 computer-aided manufacturing을 이용하여 지르코니아 프레임워크 상부에 단일 구조 지르코니아 크라운을 제작하여 현재 치열의 기능적, 심미적 회복을 하여 이에 보고하고자 한다.