• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권3호
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• pp.276-281
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• 2010

The maxillary posterior area is the most challenging site for the dental implant. After missing of teeth on maxillary posterior area due to periodontal problems, the remaining alveolar ridge is usually very thin because of not only pneumatization of maxillary sinus but also destruction of alveolar bone. The maxillary sinus bone graft procedure is one of the most predictable and successful treatments for the rehabilitation of atrophic and pneumatized endentulous posterior maxilla. But, in case of severe destruction of alveolar bone due to periodontal problems, very long crown length is still remaining problem after successful sinus graft procedures. We performed vertical augmentation of maxillary posterior alveolar ridge using mandibular ramal block bone graft with simultaneous sinus graft. After this procedures, we could get more favorable crown-implant ratio of final prosthodontic appliance and more satisfactory results on biomechanics. This is a preliminary report of the vertical augmentation of maxillary posterior alveolar ridge using mandibular ramal block bone graft with simultaneous sinus graft, so requires more long-term follow up and further studies.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2005년도 춘계 국제심포지엄 및 학술대회
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• pp.51-82
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• 2005

To compare the pulmonary toxicity between ultrafine colloidal silica particles (UFCSs) and fine colloidal silica particles (FCSs), mice were intratracheally instilled with 3 mg of 14-nm UFCSs and 230-nm FCSs and pathologically examined from 30 mill to 24 hr post-exposure. Histopathologically, lungs exposed to both sizes of particles showed bronchiolar degeneration and necrosis, neutrophilic inflammation in alveoli with alveolar type II cell proliferation and particle-laden alveolar macrophage accumulation. UFCSs, however, induced extensive alveolar hemorrhage compared to FCSs from 30 min onwards. UFCSs also caused more severe bronchiolar epithelial cell necrosis and neutrophil influx in alveoli than FCSs at 12 and 24 hr post-exposure. Laminin positive immunolabellings in basement membranes of bronchioles and alveoli of UFCSs treated animals was weaker than those of FCSs treated animals in all observation times. Electron microscopy demonstrated UFCSs and FCSs on bronchiolar and alveolar wall surface as well as in the cytoplasm of alveolar epithelial cells, alveolar macrophages and neutrophils. Type I alveolar epithelial cell erosion with basement membrane damage in UFCSs treated animals was more severe than those in FCSs treated animals. At 12 and 24 hr post-exposure, bronchiolar epithelia cells in UFCSs treated animals showed more intense vacuolation and necrosis compared to FCSs treated animals. These findings suggest that UFCSs has greater ability to induce lung inflammation and tissue damages than FCSs.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권4호
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• pp.679-700
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• 1996

Inferior alveolar nerve dysfunction may be the result of trauma, disease, or iatrogenic injury. Inferior alveolar nerve injury is inherent risk in endodontic therapy, orthognathic surgery of the mandible, and extraction of mandibular teeth, particularly the third molars. The sensory disturbances of inferior alveolar nerve associated with such injury have been well documented clinical problem that is commonly evaluated by several clinical sensory test including Tinels sign, Von Frey test(static light touch detection), directional discrimination, two-point discrimination, pin pressure nociceptive discrimination, and thermal test. These methods used to detect and assess inferior alveolar nerve injury have been subjective in nature, relying on the cooperation of the patients. In addition, many of these techniques are sensitive to differences in the examiners experience and skill with the particular technique. Data obtained at different times or by different examiners are therefore difficult to compare. Prior experimental studies have used electro diagnostic methods(sensory evoked potential) to objectively evaluate inferior alveolar nerve after nerve injury. This study was designed with inferior alveolar nerve of rabbit. Several types of injury including mind, moderate, severe compression and perforation with 19 gauze, 21 gauze needle and 6mm, 10mm traction were applied for taking the sesory evoked ppterntial. Latency and amplitude of injury rabbit inferior alveolar nerve were investigated with sensory evoked potential using unpaired t-test. The results were as follows : 1. Intensity of threshold (T1) was $128{\pm}16{\mu}A$ : latency, $0.87{\pm}0.07$ microsecond : amplitude, $0.4{\pm}0.1{\mu}V$ : conduction velocity, 23.3 m/s in sensory evoked potential of uninjured rabbit inferior alveolar nerve. 2. Rabbit inferior alveolar nerve consists of type II and III sensory nerve fiber. 3. Latency was increased and amplitude was decreased in compression injury. The more injured, the more changed in latency and amplitude. 4. Findings in perforation injury was similar to compression injury. Waveform for sensory evoked potential improved by increasing postinjured time. 5. Increasing latency was prominent in traction injury rabbit inferior alveolar nerve. 6. In microscopic histopathological findings, significant degeneration and disorganization of the internal architecture were seen in nerve facicle of severe compression and 10mm traction group. From the above findings, electrophysiological assessment(sensory evoked potential) of rabbit injured inferior alveolar nerve is reliable technique in diagnosis and prognosis of nerve injury.

• Journal of Dental Anesthesia and Pain Medicine
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• 제15권2호
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• pp.93-96
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• 2015

Although inferior alveolar nerve block is one of the most common procedures performed at dental clinics, complications or adverse effects can still occur. On rare occasions, ocular disturbances, such as diplopia, blurred vision, amaurosis, mydriasis, abnormal pupillary light reflex, retrobulbar pain, miosis, and enophthalmos, have also been reported after maxillary and mandibular anesthesia. Generally, these symptoms are temporary but they can be rather distressing to both patients and dental practitioners. Herein, we describe a case of diplopia caused by routine inferior alveolar nerve anesthesia, its related physiology, and management.

• 대한치과교정학회지
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• 제29권2호
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• pp.209-217
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• 1999

하악 전돌자에서의 치은퇴축 발생 소인을 알아보기 위하여 20세 전후의 악교정수술을 요하는 하악전돌자와 비슷한 연령대의 정상교합자를 대상으로 측모 두부방사선 사진과 하악 전치부의 단층 촬영사진을 사용하여 순측 치조골 계측치를 비교 연구한 바 다음과 같은 결과를 얻었다. 1. 하악전돌자의 순측 치조골 피질판의 단면적은 정상군보다 의미있게 작았다. 2. 하악전돌자의 치조정은 정상군에 비하여 낮은 것으로 나타났다. 3. 순측 치조골판의 면적은 백아법랑질 경계에서 치조정까지의 거리와는 역상관관계를, 치조정에서 치근단까지의 거리와는 순상관관계를 보였다. 4. 하악전돌자에서 IMPA의 증가는 symphysis의 두께와 순상관 관계를, 치조골의 높이와는 역상관 관계를 보였다. 이상의 결과에서 골격성 하악전돌자는 변연부 순측 치조골이 정상교합자보다 작음으로 치은퇴축 발생 가능성이 큼을 시사하였다.

• 대한치과교정학회지
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• 제28권6호
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• pp.905-914
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• 1998

본 연구의 목적은 1) 편측성 순구개열 신생아 환자에 대한 술전 비치조 정형장치(PNAM) 치료를 소개하고, 2) 이 장치의 치조골 정형 효과를 평가하는 것이다. 서울대학교병원 교정과에 내원하여 PNAM장치를 사용하여 치료받은 4명의 편측성 순구개열 환자(남자 3명, 여자 1명, 평균 초진연령 : 23.2일)을 대상으로 하였으며, 치조골에서 대분절과 소분절 파열부간의 평균거리는 8.27mm였고 치조골 정형치료의 평균 기간은 9.7주였다. 초진시 (Ti)와 성공적인 치조골 정형술이 이루어진 시기(T2)에 이들 환자의 인상을 채득하여 모형을 제작한 후, 사진촬영과 digital caliper를 사용하여 7개의 길이항목과 5개의 각도항목을 계측하였다. SPSS win. ver 7.5 프로그램을 사용하여 통계처리하였고, 평균치의 차이를 비교하기 위하여 paired t-test를 사용하였다. 1. 신생아의 치조골 후방부는 치조골 정형술을 시행하는 동안 안정된 구조물이었다. 2. 치조골 정형술에 의하여 대분절의 전방 성장이 억제되었다. 3. 피조골 정형술에 의한 파열부의 폐쇄는 주로 대분절 전방부의 내측과 후방 굴곡 및 소분절 전체의 외측 굴곡에 의한 것이었다.

• 대한치과교정학회지
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• 제54권2호
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• pp.79-88
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• 2024

Objective: Alveolar bone loss is a common adverse effect of intrusion treatment. Mandibular incisors are prone to dehiscence and fenestrations as they suffer from thinner alveolar bone thickness. Methods: Thirty skeletal class II patients treated with mandibular intrusion arch therapy were included in this study. Lateral cephalograms and cone-beam computed tomography images were taken before treatment (T1) and immediately after intrusion arch removal (T2) to evaluate the tooth displacement and the alveolar bone changes. Pearson's and Spearman's correlation was used to identify risk factors of alveolar bone loss during the intrusion treatment. Results: Deep overbite was successfully corrected (P < 0.05), accompanied by mandibular incisor proclination (P < 0.05). There were no statistically significant change in the true incisor intrusion (P > 0.05). The labial and lingual vertical alveolar bone levels showed a significant decrease (P < 0.05). The alveolar bone is thinning in the labial crestal area and lingual apical area (P < 0.05); accompanied by thickening in the labial apical area (P < 0.05). Proclined incisors, non-extraction treatment, and increased A point-nasion-B point (ANB) degree were positively correlated with alveolar bone loss. Conclusions: While the mandibular intrusion arch effectively corrected the deep overbite, it did cause some unwanted incisor labial tipping/flaring. During the intrusion treatment, the alveolar bone underwent corresponding changes, which was thinning in the labial crestal area and thickening in the labial apical area vice versa. And increased axis change of incisors, non-extraction treatment, and increased ANB were identified as risk factors for alveolar bone loss in patients with mandibular intrusion therapy.

• 대한치과교정학회지
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• 제48권6호
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• pp.367-376
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• 2018

Objective: This study was performed to investigate the changes in alveolar bone after maxillary incisor intrusion and to determine the related factors in deep-bite patients. Methods: Fifty maxillary central incisors of 25 patients were evaluated retrospectively. The maxillary incisors in Group I (12 patients; mean age, $16.51{\pm}1.32years$) were intruded with a base-arch, while those in Group II (13 patients; mean age, $17.47{\pm}2.71years$) were intruded with miniscrews. Changes in the alveolar envelope were assessed using pre-intrusion and post-intrusion cone-beam computed tomography images. Labial, palatal, and total bone thicknesses were evaluated at the crestal (3 mm), midroot (6 mm), and apical (9 mm) levels. Buccal and palatal alveolar crestal height, buccal bone height, and the prevalence of dehiscence were evaluated. Two-way repeated measure ANOVA was used to determine the significance of the changes. Pearson's correlation coefficient analysis was performed to assess the relationship between dental and alveolar bone measurement changes. Results: Upper incisor inclination and intrusion changes were significantly greater in Group II than in Group I. With treatment, the alveolar bone thickness at the labial bone thickness (LBT, 3 and 6 mm) decreased significantly in Group II (p < 0.001) as compared to Group I. The LBT change at 3 mm was strongly and positively correlated with the amount of upper incisor intrusion (r = 0.539; p = 0.005). Conclusions: Change in the labial inclination and the amount of intrusion should be considered during upper incisor intrusion, as these factors increase the risk of alveolar bone loss.

• Journal of Periodontal and Implant Science
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• 제41권2호
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• pp.60-66
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• 2011

Purpose: The aim of this study is to evaluate the buccal and lingual bone thickness in the anterior teeth and the relationship between bone thickness and the tissue biotype. Methods: Three male and two female human cadaver heads (mean age, 55.4 years) were used in this study. First, the biotype of periodontium was evaluated and categorized into a thick or a thin group. Next, full thickness reflections of the mandible and the maxilla to expose the underlying bone for accurate measurements in the anterior regions were performed. After the removal of the half of the alveolar bone, the probe with a stopper was used to measure the thickness of bone plate at the alveolar crest (AC), 3 mm apical to the alveolar crest (AC-3), 6 mm apical to the alveolar crest (AC-6), and 9 mm apical to the alveolar crest (AC-9). The thickness of the buccal plates at the alveolar crest were $0.97{\pm}0.18\;mm$,$0.78{\pm}0.21\;mm$, and $0.95{\pm}0.35\;mm$ in the maxillary central incisors, lateral incisors, and canines, respectively. The thickness of the labial plates at the alveolar crest were $0.86{\pm}0.59\;mm$, $0.88{\pm}0.70\;mm$, and $1.17{\pm}0.70\;mm$ in the mandibular central incisors, lateral incisors and canines, respectively. Conclusions: The thickness of the labial plate in the maxillary anteriors is very thin that great caution is needed for placing an implant. The present study showed the bone thickness of maxillary and mandibular anteriors at different positions. Therefore, these data can be useful for the understanding of the bone thickness of the anteriors and a successful implant placement.

• Journal of Periodontal and Implant Science
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• 제35권1호
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• pp.251-261
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• 2005

Alveolar ridge defects may limit or restrict placement of implants. The purpose of this study was to evaluate clinical and histopathologic results which occur following guided bone regeneration using platelet-rich plasma, bovine bone powder and e-PTFE membrane in the localized alveolar bone defects. Ten patients who required guided bone regeneration in implant placemnet, were slelected. Alveolar crest height and width were measured at baseline and, afer 2nd surgery 5 months later At 5 months , we obtained histopathological results as follows: 1. Alveolar crest height was an average of $8.20{\pm}3.74$ mm preoperatively and decreased to an average of $7.40{\pm}1.84$ mm postoperatively. There was no significant difference. 2. Alveolar crest width was an average of $4.25{\pm}2.03$ mm preoperatively and significantly increased to an average of $7.20{\pm}2.44$ mm postoperatively (P<0.01) 3. The change of Alveolar crest height and width were $0.80{\pm}1.40$ mm, $2.95{\pm}1.09$ mm 4. Histopathological evaluations revealed new bone formation with graft material and laminated bone containing the presence of osteocyte-like cell In conclusion, guided bone regeneration using platelet-rich plasma, bovine bone powder and e-PTFE membrane would provide a viable therapeutic alternative for implant placement in the localized alveolar defect or implant failure