• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.27.1-27.9
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• 2019

Background: Implants are becoming the first choice of rehabilitation for tooth loss. Even though they have a high success rate, failures still occur for many reasons. The objective of this study is to analyze the reasons for recurring failure at the same site and the results of re-implantation. Methods: Thirteen patients (11 males and 2 females, mean age 60 ± 9.9 years) who experienced implant surgery failure at the same site (same tooth extraction area) two or more times in the Department of Oral and Maxillofacial Surgery, Seoul National University Bundang Hospital, between 2004 and 2017 were selected. The medical records on a type, sites, diameter, and length of implants; time and estimated cause of failure; and radiographs were reviewed. Data were collected and analyzed retrospectively, and the current statuses were evaluated. Results: A total of 14 implants experienced failure in the same site more than two times. Twelve implants were placed in the maxilla, while 2 implants were placed in the mandible. The maxillary molar area was the most common site of failure (57.1%), followed by the mandibular molar, anterior maxilla, and premolar areas (14.3% each). The first failure occurred most commonly after prosthetic treatment (35.7%) with an average period of failure of 3.8 months after loading. Ten cases were treated as immediate re-implantation, while the other 4 were delayed reimplantation after an average of 3.9 months. The second failure occurred most commonly after prosthetic treatment (42.9%), with an average of 31 months after loading; during the healing period (42.9%); and during the ongoing prosthetic period (14.3%). In 3 cases (21.4%), the treatment plan was altered to an implant bridge, while the other 11 cases underwent another implant placement procedure (78.6%). Finally, a total of 9 implants (64.3%) survived, with an average functioning period of 60 months. Conclusions: Implants can fail repeatedly at the same site due to overloading, infection, and other unspecified reasons. The age and sex of the patient and the location of implant placement seem to be associated with recurring failure. Type of implant, bone augmentation, and bone materials used are less relevant.

• 대한장애인치과학회지
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• 제2권1호
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• pp.39-44
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• 2006

Cerebral palsy(CP) is one of the most common motor disease, due to brain injury during fetal and neonatal development which results in neuromotor paralysis and associated neuromuscular symptoms. Features of CP include motor disability due to the lack of muscle control, often accompanied by sensory disorders, mental retardation, speech disorders, hearing loss, epilepsy, behavior disorders, etc. There are increasing chances of treatment of dental patients with cerebral palsy, as the occurrence of CP is increasing with the decrease in infant mortality and an increase in immature birth and premature birth and also, there is a trend to pursue of higher quality of life. Reports on the relationship between CP and maxillofacial deformity are uncommon, but it is well known that the unbalance and discontrol of the facial muscles, lip, tongue and the jaws leads to malocclusion and temporomandibular joint disorders, and statistics show that class 2 relationship of the jaws and open bite is frequently reported. However, it is difficult to perform maxillofacial deformity treatment, which consists of orthodontic treatment, maxillofacial surgery and muscle adaptation training, due to difficulties in communication and problems of muscle adaptation caused by difficulties in motor control which leads to a high recurrence rate. This case report is to trearment of maxillofacial deformity in CP patient. A 26 year old female patient came to the department with the chief complaint of prognathism of the mandible and facial asymmetry. According to the past medical history, she was diagnosed as cerebral palsy 1 week after birth, classified as GMFC, classII accompanied with left side torticollis. The patient's intelligence was moderate, and there were no serious problems in communication. For two years time, the patient underwent lingual frenectomy, pre-operation orthodontic treatment and then bimaxillary orthognathic surgery to treat mandibular prognathism and facial asymmetry followed by rehabilitatory exercise of facial muscle. After 6 months of follow up, there was a good result. This is to report to the typical signs and symptoms of DFD in CP patient and the limitation of the usual method of the treatment of DFD in CP patient with literature review.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제37권
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• pp.34.1-34.14
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• 2015

Background: Over the past 30-40 years, various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). The aim of this study is to present the long-term clinical results of carbon/carbon implants, and the results of the scanning electron microscope and energy dispersive spectrometer investigation of an implant retrieved from the human body after 8 years. Methods: Mandibular reconstruction (8-10 years ago) was performed with pure (99.99 %) carbon implants in 16 patients (10 malignant tumours, 4 large cystic lesions and 2 augmentative processes). The long-term effect of the human body on the carbon/carbon implant was investigated by comparing the structure, the surface morphology and the composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Results: Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. During the long-term follow-up, plate fracture, loosening of the screws, infection or inflammations around the carbon/carbon implants were not observed. The thickness of the carbon fibres constituting the implants did not change during the 8-year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering implants. Conclusions: The surface morphology and the structure were not changed after 8 years. The two main components of the implant retrieved from the human body are still carbon and oxygen, but the amount of oxygen is 3-4 times higher than on the surface of the reference implant, which can be attributed to the oxidative effect of the human body, consequently in the integration and biocompatibility of the implant. The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권3호
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• pp.176-183
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• 2011

Introduction: Very high aggressiveness and recurrence are important clinical characteristics of ameloblastoma compared to the other benign tumors. Therefore, an accurate diagnosis and treatment plan is important. This study examined the association of the clinical findings and recurrence based on the radiological findings of ameloblastoma. In recurrent cases, these results are expected to help in the diagnosis and treatment of ameloblastoma to examine the relevance with the clinical characteristics and radiological features. Materials and Methods: For a clinical (gender, age) and radiological (location, internal pattern, size, perforation, border pattern, impacted tooth, root resorption) evaluation, this study examined 156 cases of 147 patients diagnosed with ameloblastoma, who had been treated and in most cases regularly checked at the department of oral and maxillofacial surgery, Kyungpook National University Hospital, between January 1993 and December 2009. For a recurrent rate evaluation, a more than 3 years follow-up period is needed. Accordingly, 116 patients diagnosed with ameloblastoma between January 1994 and December 2007 were investigated. Results: The recurrence rate in all cases was 6.1% but was 7.8% in cases with follow-up periods more than 3 years. The male-to-female ratio was 3:2, showing a slight male predilection. Ameloblastoma had a peak occurrence in the second decade of life followed by the fourth decade of life. The mandibular angle area is the most frequent site of ameloblastoma (50.8%) in the jaws. Six cases of unilocular (7.8%) and 3 cases of multilocular (7.7%) ameloblastomas recurred. Seven cases of smooth (10%) and 2 cases of irregular (4.3%) ameloblastomas recurred. No cases of ameloblastomas without perforation of the cortical bone (0%) and 9 cases with a perforation of cortical bone (11.1%) recurred. Four cases of the ameloblastomas with impacted teeth (11.4%) and 5 cases of ameloblastomas without impacted tooth (6.2%) recurred. Seven cases of ameloblastomas with root resorption (10.9%) and 2 cases of ameloblastomas without root resorption (3.8%) recurred. Conclusion: A multiple smooth margin, unilocular ameloblastoma with an impacted tooth, root resorption tends to recur more easily. Therefore, they need to be treated more carefully and require a a longer follow-up.

• Imaging Science in Dentistry
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• 제46권1호
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• pp.25-31
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• 2016

Purpose: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. Materials and Methods: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using 3D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. Results: The mean of the average point-to-point distances on condylar surface was $0.11{\pm}0.03mm$. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. Conclusion: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

• 구강회복응용과학지
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• 제35권4호
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• pp.244-252
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• 2019

상악 전치의 위치 결정은 수술을 동반한 교정치료의 성공을 위해 꼭 필요한 열쇠이다. 따라서 상악 전치가 전부 소실된 환자에서 수술계획을 수립하는 것은 매우 어려운 일이다. 본 환자는 상악 전치를 외상으로 인해 모두 상실하였으며, 보철 치료를 위한 교정치료를 주소로 내원하였다. 보철 개수를 최소화할 수 있도록 상악의 악궁 형태를 변형하여 4개의 보철 공간을 확립하여 술전교정을 진행하였으며, 3D 가상 보철수복을 참고하여 상악 전치의 위치를 결정하고 하악골 편악수술을 시행하였다. 악교정수술 시 상악골 이식술 및 임플란트 식립이 함께 진행되었으며 비교적 짧은 28개월의 교정치료 기간 후 치료를 마무리하였다. 골격성 III급 환자가 전치 소실 후 치조골이 함께 흡수된 경우 하악궁과의 조화로운 보철수복이 매우 어려우며, 이와 같은 경우에 전략적인 술전교정을 통해 하악골 후방이동수술을 시행하는 것이 더 나은 치료 환경을 제공할 수 있을 것이다.

• Journal of Periodontal and Implant Science
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• 제51권6호
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• pp.374-385
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• 2021

Purpose: The aim of this study was to evaluate the effects of locally delivered 1% alendronate (ALN) gel used as an adjunct to non-invasive periodontal therapy. Methods: Ligature-induced periodontitis was performed in 96 rats. The ligature was tied in the cervical area of the mandibular left first molar. The animals were randomly divided into 4 groups: 1) NT, no treatment; 2) SRP, scaling and root planning; 3) SRP/PLA, SRP followed by filling the periodontal pocket with placebo gel (PLA); and 4) SRP/ALN, SRP followed by filling the periodontal pockets with 1% ALN gel. Histomorphometric (percentage of bone in the furcation region [PBF]) and immunohistochemical (receptor activator of nuclear factor-κB ligand, osteoprotegerin, and tartrate-resistant acid phosphatase) analyses were performed. Data were statistically analyzed, with the threshold of statistical significance set at P≤0.05. Results: The SRP, SRP/PLA, and SRP/ALN groups presented a higher PBF than the NT group (P≤0.01) at 7, 15, and 30 days. The SRP/ALN group presented a higher PBF than the SRP/PLA group in all experimental periods, as well as a higher PBF than the SRP group at 15 and 30 days. No differences were observed in the immunohistochemical analyses (P>0.05 for all). Conclusions: Locally delivered 1% ALN gel used as an adjunct to SRP enhanced bone regeneration in the furcation region in a rat model of experimental periodontitis.

• 대한치과보철학회지
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• 제60권3호
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• pp.283-292
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• 2022

임플란트를 이용한 고정성 보철 치료를 위해서는 보철 치료에 적합한 위치에 임플란트가 식립되어야 하며 이를 위해 guided implant surgery와 CAD-CAM을 활용한 보철물 제작이 최근 널리 사용되고 있다. 수술 시에는 surgical guide를 이용해 flapless 방식으로 최소침습 보철수복이 가능 하다. 본 증례의 환자는 86세 남성 환자로 기존 의치 사용 시 불편함으로 치료를 원하였다. 환자는 전신질환으로 인해 가철성 국소의치 사용이 어려워 상악은 총의치, 하악의 경우 임플란트 고정성 보철물 수복하였다. 전신질환으로 인해 높은 출혈 위험성을 가지므로 surgical guide를 사용해 flapless 방식으로 임플란트를 식립하였다. 최종적으로 상악 총의치 및 하악 나사 유지형 지르코니아를 보철물을 제작하였으며, 만족스러운 기능 및 심미 회복을 보였기에 보고하는 바이다.

• 대한치과교정학회지
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• 제19권1호
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• pp.169-185
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• 1989

정상교합 및 안모가 단정한 성인(남자 60명, 여자 62명)을 대상으로 악교정수술을 위한 한국인 기준치를 얻고자 측모 두부방사선 규격사진을 이용하여 계측 분석과 결과 다음과 같은 결론을 얻었다. 카 계측항목의 평균치, 표준편차를 구하였다. 골격계측 항목중 각도계측치에서는 FH-SN과 SN-MP가 여자에서 더 크며, 거리계측치에서는 전 항목에서 남자가 더 큰 것으로 나타났다. 치아계측 항목에서는 수직적 관계를 나타내는 항목에서만 남녀간에 유의한 차를(P<0.05) 보였는데 ADH, PDH, overbite에서는 여자가 더 크고 Incisor exposure에서는 여자가 더 크게 나타났다. 연조직계측 항목에서는 NLA를 제외한 전 항목 즉 FCA, UFH, ULL, LLL에서 남자가 여자보다 더 크게 나타났다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권2호
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• pp.79-85
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• 2003

The purpose of this study is to observe histopathologic changes in the bilateral craniomandibular joints after allowing 6 weeks of consolidation by varying the amount of distraction in rabbit mandible. Eight rabbits weighing about 2 to 3 kg were used. After corticotomy was performed on the left mandibular body between the first premolar and the second premolar region, a unilateral fixation device was placed. Then, a 7-day period was allowed without distraction of the device. The mandible was lengthened 0.5 mm/day. Corticotomy and lengthening of mandible were not performed in control group. After the completion of the lengthening process, a 6-week-consolidation period was allowed. Then, the rabbits were sacrificed, and histologic examination of the craniomandibular joints was performed. Proliferative changes were observed in the craniomandibular joints in all groups. With the increasing amount of distraction, hypertrophy of the cartilage layer became more severe, bone formed was dense and enchondral ossification was clearly shown in subchondral bone. Hypertrophy of the cartilage layer was also seen in the non-distracted side as the distracted side in the experimental group. These results indicate that when physical force is applied constantly to joints, the proliferation of articular cartilage and bone formation are present. When more than 6 weeks of consolidation period is allowed at the time of performing distraction for more than 5 mm, articular changes, especially, in the contralateral side should also be noted.