• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제28권4호
• /
• pp.249-255
• /
• 2002

Recently, Skeletal Anchorage System (SAS) has been focused clinically with the view point that it could provide the absolute intraoral anchorage. First, it began to be used for the patient of orthognathic surgery who had difficulty in taking intermaxillary fixation due to multiple loss of teeth. And then, its uses have been extended to many cases, the control of bone segments after orthognathic surgery, stable anchorage in orthodontic treatment, and anchorage for temporary prosthesis and so on. SAS has been developed as dental implants technique has been developed and also called in several names; mini-screw anchorage, micro-screw anchorage, mini-implant anchorage, micro-implant anchorage (MIA), and orthosystem implant etc. Now many clinicians use SAS, but the anatomical knowledges for the installed depth of intraosseous screws are totally dependent on general experiences. So we try to study for the cortical thickness of maxilla and mandible in Korean adults without any pathologic conditions with the use of Computed Tomography at the representative sites for the screw installation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제41권5호
• /
• pp.251-258
• /
• 2015

Objectives: This study was performed to evaluate the impact of glycosylated hemoglobin (HbA1c) level on characteristics and prognosis of maxillofacial fascial infection in diabetic patients. Materials and Methods: We reviewed the medical records of 72 patients (35 patients with HbA1c lower than 7.0% and 37 patients with HbA1c higher than 7.0%) diagnosed with maxillofacial fascial space infection and hospitalized for treatment at the Department of Oral and Maxillofacial Surgery in Dankook University Hospital (Cheonan, Korea) from January 2005 to February 2014. We compared demographics, parameters of glucoregulation (HbA1c), laboratory parameters of inflammation (white blood cell [WBC], C-reactive protein [CRP] count), type and number of involved spaces, type and number of antibiotics, period of hospitalization, number of surgical operations, need for tracheostomy, complications, computed tomography (CT), and microorganisms between the two groups. Results: Compared with the well-controlled diabetes mellitus (DM) group (HbA1c <7.0%), patients in the poorly-controlled (HbA1c ${\geq}7.0%$) DM group had the following characteristics: longer hospitalization periods, higher values of laboratory parameters of inflammation (WBC, CRP count) at the time of admission, higher number of antibiotics prescribed, more frequent complications, frequent deep neck space involvement, and distinctive main causative microorganisms. As the HbA1c level increases, hospitalization periods and incidence of complications increase gradually. Conclusion: This retrospective study suggests that regulation of DM significantly impacts maxillofacial fascial infection. Poorly controlled DM with high HbA1c level negatively influences the prognosis of infection.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제37권1호
• /
• pp.54-61
• /
• 2011

Introduction: Bisphosphonates is used widely for the treatment of the Paget's disease, multiple myeloma, bone metastases of malignant tumors with the prevention of pain and their pathological fracture. However, it was recently suggested that bisphosphonates related osteonecrosis of the jaw (BRONJ) is a side effect of bisphosphonate use. Materials and Methods: Twenty-four individuals, who were referred to the Department of Oral and Maxillofacial surgery, Dankook University Dental Hospital, were selected from those who had exposed bone associated with bisphosphonates from January, 2005 to December, 2009 according to the criteria of American Association of Oral and Maxillofacial Surgeons (AAOMS) for BRONJ. The patients group consisted of 7 males and 17 females between the age of 46 to 78 years (average 61.8 years). Each patient had panoramic imaging, computed tomography (CT), whole body bone scanning performed for a diagnosis and biopsy sampling from the necrotizing tissue. C-terminal cross-linking telopeptide of type I collagen (CTX) level of patients who had undergone surgical intervention was measured 7 days before surgery. Results: The main cause of bone exposure was post-extraction (15), chronic periodontitis (4), persistent irritation of the denture (3). Twenty people had undergone BRONJ treatment for two to eight months except for 4 people who had to maintain the bisphosphonates treatment to prevent a metastasis and bone trabecular pain with medical treatment. When the bisphosphonate treatment was suspended at least for 3 months and followed up according to the AAOMS protocols, the exposed necrotizing bones were found to be covered by soft tissue. Conclusion: Prevention therapy, interruption of bisphophonates for at least 3 months and cooperation with the physician for conservative treatment are the essential for treating BRONJ patient with high risk factors. The CTX level of BRONJ patients should be checked before undergoing surgical intervention. Surgical treatments should be delayed in the case of a CTX level <150 pg/mL.

• 대한방사선기술학회지:방사선기술과학
• /
• 제23권1호
• /
• pp.63-76
• /
• 2000

License system of radiologic technologists has been started since 1965 in Korea. This study is to explore directions on radiotechnologists' license system classified by subspecialty. For this purpose, the authors surveyed on radiotechnologists' license system classified by subspecialty, with the subject related to radiotechnologic societies. Additionally, data on qualification and license system associated with medical and health care field were collected. The results are as follows. 1. The main body for subspecialty system for radiologic technologists should be the Korea Radiologic Technologists Association and the Association should maintain a close cooperation with radiotechnologic societies. 2. A radiologic technologist should be a basic role once they pass the license examination. In addition, they can get a special qualification by subspecialty in radiologic technology. 3. Radiotechnologists' license system classified by subspecialty will be keep priorities in order and done systematically. Execution order is as follows ; This study proposes that radiotechnologists responsible for ultrasonography, computed tomography(CT), magnetic resonance imaging(MRI) and security management be started for the first stage. For the second stage, radiotechnologists for mammography, angio-cardiography, digital imaging, maxillo-facial and dental radiography, nuclear medicine, radio-therapeutic field should be in force. 4. Professional education course(basic and intensive) and clinical training program have to be made for the eligibility of radiotechnologists' license system classified by subspecialty. 5. Eligibility system of radiotechnologists' license system classified by subspecialty(non-government or government) has to be made. Further more, inquiry commission to investigate eligibility for radiotechnologists' license system should be established.

• Restorative Dentistry and Endodontics
• /
• 제41권1호
• /
• pp.22-28
• /
• 2016

Objectives: The goal of this study was to compare the density of gutta-percha root fillings obturated with the following techniques: cold lateral (CL) compaction, ultrasonic lateral (UL) compaction, and warm vertical (WV) compaction. Materials and Methods: Thirty-three extracted mandibular first molars, with two separate mesial canals in each, were selected. After instrumentation, the canals were stratified into three groups based on canal length and curvature, and underwent obturation with one of the techniques. No sealer was used in order to avoid masking any voids. The teeth were imaged pre- and post-obturation using micro-computed tomography. The reconstructed three-dimensional images were analyzed volumetrically to determine the amount of gutta-percha present in every 2 mm segment of the canal. P values < 0.05 were considered to indicate statistical significance. Results: The overall mean volume fraction of gutta-percha was $68.51{\pm}6.75%$ for CL, $86.56{\pm}5.00%$ for UL, and $88.91{\pm}5.16%$ for WV. Significant differences were found between CL and UL and between CL and WV (p < 0.05), but not between UL and WV (p = 0.526). The gutta-percha density of the roots treated with WV and UL increased towards the coronal aspect, but this trend was not noted in the CL group. Conclusions: WV compaction and UL compaction produced a significantly denser gutta-percha root filling than CL compaction. The density of gutta-percha was observed to increase towards the coronal aspect when the former two techniques were used.

• Imaging Science in Dentistry
• /
• 제41권4호
• /
• pp.143-150
• /
• 2011

Purpose : The aim of this study was to compare the diagnostic accuracy of cone-beam computed tomography (CBCT) images and bitewing images in detection of secondary caries. Materials and Methods : One hundred and twenty proximal slots of Class II cavities were randomly prepared on human premolar and molar teeth, and restored with amalgam (n=60) and composite resin (n=60). Then, artificial secondary caries lesions were randomly created using round steel No. 4 bur. The teeth were radiographed with a conventional bitewing technique and two CBCT systems; Pax-500ECT and Promax 3D. All images were evaluated by five observers. The area under the receiver operating characteristic (ROC) curve ($A_z$) was used to evaluate the diagnostic accuracy. Significant difference was tested using the Friedman test (p value<0.05). Results : The mean $A_z$ values for bitewing, Pax-500ECT, and Promax 3D imaging systems were 0.882, 0.995, and 0.978, respectively. Significant differences were found between the two CBCT systems and film (p=0.007). For CBCT systems, the axial plane showed the greatest $A_z$ value. Conclusion : Based on the design of this study, CBCT images were better than bitewing radiographs in detection of secondary caries.

• Imaging Science in Dentistry
• /
• 제35권2호
• /
• pp.77-82
• /
• 2005

Purpose : To reveal what is the distinct differential diagnostic differences between unicystic ameloblastoma and solid or multicystic ameloblastoma. Materials and Methods : 56 cases of ameloblastoma were retrospectively reviewed and evaluated among the patients who had taken CT scans at the department of Oral & Maxillofacial Radiology in Yonsei University Dental Hospital from January 1996 to December 2003. Results : In 56 cases, 21 cases $(37.5\%)$ were unicystic ameloblastoma, 35 cases $(62.5\%)$ were solid or multicystic ameloblastoma. Only 1 case $(4.8\%)$ of unicystic ameloblastoma and 4 cases $(11.4\%)$ of solid or multicystic ameloblastoma were occurred in maxilla. 13 cases $(61.9\%)$ of unicystic ameloblastoma were observed as unilocular, and 8 cases $(38.1\%)$ as lobulated. 5 cases $(14.3\%)$ of solid or multicystic ameloblastoma were observed as unilocular, 13 cases $(37.1\%)$ as lobulated, and 17 cases $(48.6\%)$ as multilocular. Tn the results from the measurements after correction of the buccolingual widths and heights to the mesiodistal lengths, there is a statistically significant difference between unicystic ameloblastoma and solid or multicystic ameloblastoma in ANCOVA test (p<0.05). Hounsfield units in the lesion were $24.9{\pm}8.8\;HU$ in unicystic ameloblastoma, $31.2{\pm}11.5\;HU$ in solid or multicystic ameloblastoma. There is no statistically significant difference (p>0.05). Conclusion : Characteristic differences between unicystic ameloblastoma and solid or multicystic ameloblastoma is that there is higher prevalence of solid or multicystic ameloblastoma that have lobulated or multilocular patterns. To measure the Hounsfield units in the lesion is helpful, but it is not a differential diagnostic point between unicystic ameloblastoma and solid or multicystic ameloblastoma.

• Journal of Periodontal and Implant Science
• /
• 제28권2호
• /
• pp.377-388
• /
• 1998

This double-blind controlled clinical and microbiological study was carried out to determine the effects of mouthwash preparation containing the mixture of herbal extract on developing plaque and gingivitis in the experimental gingivitis model. Following a 2-week normalization period, 34 dental students were distributed randomly into 1 of 3 treatment groups. They rinsed, under supervision, two times daily for 3 weeks with either normal saline(CT), 0.1% chlorhexidine(CH), or the mixture of herbal extract (HT), but refrained from any oral hygiene measures. The Plaque Index(PlI), the Gingival Index(GI), and the amount of Gingival Crevicular Fluid(GCF) were measured at week 0,1,2, and 3 of the experimental period, while the assessment of total wet weight of plaque and the phase contrast microscopic examination of plaque were performed at the end of experimental period(3 weeks). Subjects using mouthrinse preparation containing the mixture of herbal extract demonstrated negligible, if any, changes in the accumulation and microbial composition of plaque compared to those using normal saline, while the reduction of gingival inflammation by this mixture was highly significant and comparable to that of chlorhexidine. The results of this study indicate that the preparation containing the mixture of herbal extract do not provide any antiplaque benefits but is very effective in inhibiting the development of and in reducing existing experimental gingivitis when used as mouthrinse. Further research is needed to determine whether a significant reduction of gingival inflammation without a concomitant decrease in plaque accumulation is of clinical importance.

• 대한소아치과학회지
• /
• 제39권2호
• /
• pp.166-173
• /
• 2012

만곡치는 치관과 치근 사이의 경계부에서 굽어 있는 형태적 특징이 있다. 만곡치는 영구치열에서 3% 유병율을 나타내고 있으며 확실한 원인은 아직 정립된 바 없으나 유치의 외상으로 인한 계승 영구치의 만곡과 외상과 관계없는 치배의 특발성 발육장애가 2가지 주요 원인으로 추측되고 있다. 특히 만곡된 상악 절치는 흔히 맹출지연으로 인한 매복이 유발되며 이를 방치할 경우 정중선 불일치, 인접 치아의 이동에 의한 공간부족과 치조골 높이의 불일치가 발생된다. 본 증례는 상악 중절치의 매복을 주소로 한 8세 남아로 CT상 매복된 상태에서 치관부가 전비극에 근접하여 협측으로 위치되어 있으며 치근부에서 만곡이 관찰되어 교정적 견인을 시도하였으나 이동이 되지 않아 외과적 재위치술로 치료하여 양호한 결과를 얻었기에 보고하는 바이다.

• Molecules and Cells
• /
• 제41권5호
• /
• pp.476-485
• /
• 2018

Although tectorigenin (TG), a major compound in the rhizome of Belamcanda chinensis, is conventionally used for the treatment of inflammatory diseases, its effects on osteogenesis and osteoclastogenesis have not been reported. The objective of this study was to investigate the effects and possible underlying mechanism of TG on in vitro osteoblastic differentiation and in vivo bone formation, as well as in vitro osteoclast differentiation and in vivo bone resorption. TG promoted the osteogenic differentiation of primary osteoblasts and periodontal ligament cells. Moreover, TG upregulated the expression of the BMP2, BMP4, and Smad-4 genes, and enhanced the expression of Runx2 and Osterix. In vivo studies involving mouse calvarial bone defects with ${\mu}CT$ and histologic analysis revealed that TG significantly increased new bone formation. Furthermore, TG treatment inhibited osteoclast differentiation and the mRNA levels of osteoclast markers. In vivo studies of mice demonstrated that TG caused the marked attenuation of bone resorption. These results collectively demonstrated that TG stimulated osteogenic differentiation in vitro, increased in vivo bone regeneration, inhibited osteoclast differentiation in vitro, and suppressed inflammatory bone loss in vivo. These novel findings suggest that TG may be useful for bone regeneration and treatment of bone diseases.