• Title/Summary/Keyword: 안면성형

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THREE DIMENSIONAL ANALYSIS OF MAXILLOFACIAL STRUCTURE BY FRONTAL AND LATERAL CEPHALOGRAM (두부 방사선 규격사진을 이용한 악안면 구조의 3차원적 분석법)

  • Kwon, Kui-Young;Lee, Sang-Han;Kwon, Tae-Geon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.21 no.2
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    • pp.174-188
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    • 1999
  • The purpose of this study is to evaluate the precision and accuracy of a three dimensional cephalogram constructed by using the frontal and lateral cephalogram of twelve human dry skulls. After achieving the three dimensional image reconstruction program, we tried to apply this program to two dentofacial deformity patients. 1. Conventional nasion relator in cephalostat was used to reproduce the same head position for the same dry skull. The mean difference of the three dimensional cephalogram for the same dry skull was $0.34{\pm}0.33mm$. Closeness of repeated measures to each skull reveals the precision of this method for the three dimensional cephalogram. 2. Concerning the accuracy, the mean difference between the three dimensional reconstruction data and actual lineal measurements was $1.47{\pm}1.45mm$ and the mean magnification ratio was $100.24{\pm}4.68%$. This Diffrerence is attributed mainly to the ill defined cephalometric landmarks, not to the positional change of the dry skull. 3. Cephalometric measurement of lateral and frontal radiographs had no consecutive magnification ratio because of the different focus-object distance. The mean difference between the frontal and lateral cephalogram to the actual lineal measurements was $4.72{\pm}2.01mm$ and $-5.22{\pm}3.36mm$. Vertical measurements were slightly more accurate than horizontal measurements. 4. Applying to the actual patient analysis, it is recommendable to use this program for analyzing the asymmetry or spatial change after operation. The orthodontic bracket would be a favorable cephalometric landmark for constructing the three dimensional images.

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A CLINICAL STUDY ON ZYGOMATIC BONE FRACTURE (관골 골절에 대한 임상적 연구)

  • Ryu, Sun-Youl;Jung, Hyun;Park, Se-Chan;Oh, Yu-Keun;Park, Hong-Ju;So, Kwang-Sub;Cho, Yong-Ki;Oh, Hee-Kyun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.21 no.1
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    • pp.54-59
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    • 1999
  • This study was based on a series of 164 patients with zygomatic bone fracture treated at Department of Oral and Maxillofacial Surgery of Chonnam University Hospital from January 1992 to December 1996. The male-to-female ratio was 7:1. Their ages ranged from 8 to 78 years, with a median age of 35.6 years. The age frequency was highest in the second decade (30.5%), and third decade (23.8%), fifth decade (16.5%) in orders. The monthly distrbution of incidence showed October to be the month in which the greatest percentage occured (14.0%). The major cause of zygomatic bone fracture was alleged traffic accidents (53.7%). The incidence of concomitant facial bone fractures was 69,5%, and maxilla fracture (52.4%) was most frequently combined. The admission route was through emergency room (72.3%) and through outpatient department (26.8%). The incidence of associated injuries was 37.2%. The intraoral approach was the major method of treatment in zygomatic bone fracture (57.1%). The most frequent type of zygoma fracture was class IV (33.5%), and class III (25.6%) was next in order of frequency. Complications were enophthalmos (7.3%), facial asymmetry (6.7%), paresthesia (6.1%), and diplopia (2.4%) These results suggest that correct diagnosis and treatment of severity of fracture, concomitant fracture, and associated injuries are necessary, and co-operative treatment with medical department should be performed to reduce postoperative complication.

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EVALUATION OF CONDYLAR DISPLACEMENT USING COMPUTER TOMOGRAPHY AFTER THE SURGICAL CORRECTION OF MANDIBULAR PROGNATHISM (전산화단층촬영법을 이용한 하악전돌증 환자의 외과적 악교정술후 하악과두 위치 변화 검토)

  • Lee, Ho-Kyung;Jang, Hyun-Jung;Lee, Sang-Han
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.20 no.3
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    • pp.191-200
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    • 1998
  • This study was intended to perform the influence of condyle positional change after surgical correction of skeletal Class III malocclusion after orthognathic surgery in 37 patients(male 13, female 24) using computed tomogram that were taken in centric occlusion before, immediate after, and long term after surgery and lateral cephalogram that were taken in centric occlusion before, 7 days within the period of intermaxillary fixation, at the 24 hours later removing intermaxillary fixation and long term after surgery. 1. Mean intercondylar distance was $84.42{\pm}5.30mm$ and horizontal long axis of condylar angle was $12.79{\pm}4.92^{\circ}$ on the right, $13.53{\pm}5.56^{\circ}$ on the left side. Condylar lateral poles were located about 12mm and medial poles about 7mm away from the reference line(AA') on the axial tomogram. Mean intercondylar distance was $83.15{\pm}4.62mm$ and vertical axis angle of condylar angle was $76.28{\pm}428^{\circ}$ on the right, $78.30{\pm}3.79^{\circ}$ on the left. 2. In amount of set back, We found the condylar change(T2C-T1C) which had increasing tendency in group III (amount of setback : 10-15mm). but there was no statistical significance(p>0.05). 3. There was some correlation between condylar change(T2C-T1C) and TMJ dysfunction. It seemed that postoperative condylar change had influenced postoperative TMJ dysfunction, through there was no statistical significance (p>0.05). As we have observed the change of condylar axis in the group that complained of TMJ dysfunction in cases of large amount of mandibular setback. So we consider that the more trying to conserve condylar position will decrease occurrence rate of post operational TMJ dysfunction.

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THE CERVICAL ISLAND FLAP FOR INTRAORAL RECONSTRUCTION FOLLOWING EXCISION OF ORAL CANCER -REPORT OF 3 CASES- (구강암 적출후 경부 도상 피판을 이용한 구강내 결손부의 재건 -3 치험례-)

  • LEE, Seong-Geun;LIM, Jong-Soo;KIM, Kyung-Hyun;JEON, So-Yeun;CHO, Young-Sung;SHIN, Sang-Hun;CHO, Young-Cheol;SUNG, Iel-Yong;KIM, Uk-Kyu;KIM, Jong-Ryoul;CHUNG, In-Kyo;YANG, Dong-Kyu
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.20 no.3
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    • pp.263-268
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    • 1998
  • Many myocutaneous flaps have been used for the reconstruction of intraoral defects caused by the excision of oral cancer. Among these myocutaneous flaps, cervical island flap has been introduced by Farr et al. Although different in detail, this flap was designed as the platysma myocutaneous flap by Futrell et al in the supraclavicular site. Since many authors applied this flap to cover intraoral defect, they discussed deeply the blood supply of this flap. To improve further flap survival, it was modified by Tashiro et al. This flap makes its vascularity highly reliable. The amount of tissue needed for reconstruction can be accurately planned. The surgical and reconstruction procedure can be performed simply, rapidly, and effectively. Oral functions including deglutition, speech, and denture fitting are not compromised. With it's minimal deformity, new donor fields is not necessory. Of course, we keep in mind that this flap has limitations in patients where much bulk of tissue defects is needed and more than 3000 rad radiation due to the metastasis of neck lymph node is exposed. In three patients with intraoral squamous cell carcinoma($T_{1-3}N_0M_0$), we performed induction chemotherapy with FP regimen including pepleomycin. Thereafter, we ablated oral cancer and peformed reconstruction of intraoral defects with cervical island flap designed by Tashiro et al. Due to these significant benefits and minimal limitations, we have found that this flap is adequate for reconstruction of most intraoral defects following cancer ablation.

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MORPHOLOGIC STUDY FOR SAGITTAL SPLIT RAMUS OSTEOTOMY USING 3-D IMAGE IN MANDIBULAR PROGNATHISM (하악전돌자에서 3차원영상을 이용한 하악지시상분할골절단술과 관련된 하악골의 해부학적 연구)

  • Park, Chung-Ryoul;Kook, Min-Suk;Park, Hong-Ju;Oh, Hee-Kyun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.27 no.4
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    • pp.350-359
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    • 2005
  • Sagittal split ramus osteotomy(SSRO) has been commonly performed in the mandibular prognathism. The previous studies of the mandibular anatomy for SSRO have mostly been used in dry skull without consideration of age, sex or jaw relationship of patients. This study was performed to evaluate the location of mandibular canal and the anatomy of ramus, such as the location of mandibular lingula and the ramal bone marrow, which were associated with SSRO procedures, in the patients with mandibular prognathism and normal young adults by using computerized tomographs(CT) and 3D images. The young adults at their twenties, who were considered to complete their skeletal growth, and seen in the Department of Orthodontics and Oral and Maxillofacial Surgery in Chonnam National University Hospital between March 2000 and May 2003, were selected. This study was performed in 30 patients (15men, 15women) who were diagnosed as skeletal class I normal relationship, and another 30 patients (15men, 15women) who were diagnosed as skeletal class III relationship upon clinical examination and lateral cephalometric radiographs. The patients were divided into 2 groups : Class I group, the patients who had skeletal class Ⅰ normal relationship(n=30, 15men, 15women), and Class III group, the patients who had skeletal class III relationship(n=30, 15men, 15women). Facial CT was taken in all patients, and pure 3D mandibular model was constructed by V-works version 4.0. The occlusal plane was designed by three points, such as the mesiobuccal cusp of both mandibular 1st molar and the incisal edge of the right mandibular central incisor, and used as a reference plane. Distances between the tip of mandibular lingula and the occlusal plane, the sigmoid notch, the anterior and the posterior borders of ramus were measured. The height of ramal bone marrow from the occlusal plane and the distance between mid-point of mandibular canal and the buccal or lingual cortex of the mandible in the 1st and 2nd molars were measured by V-works version 4.0. Distance(Li-OP) between the occlusal plane and the tip of mandibular lingula of Class III Group was longer than that of Class I Group in men(p<0.01), but there was no significant difference in women between both groups. Distance(Li-SN) between the sigmoid notch and the tip of mandibular ligula of Class III group was longer than that of Class I Group in men(p<0.05), but there was no significant difference in women between both groups. Distance(Li-RA) between the anterior border of ramus and the tip of mandibular lingula of Class III Group was shorter than that of Class I Group in men and women(p<0.01). Distance(Li-RP) between the posterior border of ramus and the tip of mandibular lingula of Class III Group was slightly shorter than that of Class I Group in men(p<0.05), but there was no significant difference in women between both groups. Distance(RA-RP) between the anterior and the posterior borders of ramus of Class III Group was shorter than that of Class I Group in men and women(p<0.01). Longer the distance(SN-AN) between the sigmoid notch and the antegonial notch was, longer the vertical ramal length above occlusal plane, higher the location of mandibular lingula, and shorter the antero-posterior ramal length were observed(p<0.01). Height of ramal bone marrow of Class III Group was higher than that of Class I Group in men and women(p<0.01). Distance between mandibular canal and buccal cortex of Class III Group in 1st and 2nd lower molars was shorter than that of Class I Group in men and women (p<0.05 in 1st lower molar in men, p<0.01 in others). These results indicate that there are some anatomical differences between the normal occlusal patients and the mandibular prognathic patients, such as the anterior-posterior length of ramus, the height of ramal bone marrow, and the location of mandibular canal.

GENE EXPRESSION PATTERNS INDUCED BY $TAXOL^{(R)}$ AND CYCLOSPORIN A IN ORAL SQUAMOUS CELL CARCINOMA CELL LINE USING CDNA MICROARRAY (cDNA Microarray를 이용한 구강편평세포암종 세포주에서 $Taxol^{(R)}$과 Cyclosporin A로 유도된 유전자 발현양상)

  • Kim, Yong-Kwan;Lee, Jae-Hoon;Kim, Chul-Hwan
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.28 no.3
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    • pp.202-212
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    • 2006
  • It is well-known that paclitaxel($Taxol^{(R)}$), which is extracted from the pacific and English yew, has been used as a chemotherapeutic agent for ovarian carcinoma and advanced breast carcinoma and Cyclosporin A, which is highly lipophilic cyclic peptide and isolated from a fungus, has been also used as an useful immunosuppressive drug after transplantation and is associated with cellular apoptosis. Since 1953, in which James Watson, Rosalind Franklin and Francis Crick discovered the double helical structure of DNA, a few kinds of techniques for identifying gene expression have been developed. In postgenomic period, many of researchers have used the DNA microarray which is high throughput screening technique to screen large numbers of gene expression simultaneously. In this study, we searched and screened the gene expression in the oral squamous cell carcinoma cell lines treated with $Taxol^{(R)}$, cyclosporin or cyclosporin combined with $Taxol^{(R)}$ using cDNA microarray. The results were as following; 1. It was useful that the appropriate concentration of Cyclosporin A and $Taxol^{(R)}$ used in oral squamous cell carcinoma cell line was under 1${\mu}g/ml$ and 3${\mu}g/ml$. 2. In the experimental group in which $Taxol^{(R)}$ and $Taxol^{(R)}$ + Cyclosporin A were used, the cell growth was extremely decreased. 3. In the group in which Cyclosporin A was used, the MTT assay was rarely decreased which means the activity of succinyl dehydrogenase is remained in mitochondria but in the group in which the mixture of Cyclosporin A and $Taxol^{(R)}$ were used, the MTT assay was extremely decreased. 4. In the each group in which Cyclosporin A(3 ${\mu}g/ml$) and $Taxol^{(R)}$(1 ${\mu}g/ml$) were used, the cell arrest was appeared in $G_2/M$ phase and in the group in which $Taxol^{(R)}$(3 ${\mu}g/ml$) was used, the cell arrest was appeared in both S phase and $G_2/M$ phase. 5. In the oral squamous cell carcinoma cell line treated with $Taxol^{(R)}$, several genes including ANGPTL4, RALBP1 and TXNRD1, associated with apoptosis, SUI1, MAC30, RRAGA and CTGF, related with cell growth, HUS1 and DUSP5, related with cell cycle and proliferation, ATF4 and CEBPG, associated with transcription factor, BTG1 and VEGF, associated with angiogenesis, FDPS, FCER1G, GPA33 and EPHA4 associated with signal transduction and receptor activity and AKR1C2 and UGTA10 related with carcinogenesis were detected in increased levels. The genes that showed increaced expression in the oral squamous cell carcinoma cell line treated with Cyclosporin A were CYR61, SERPINB2, SSR3 and UPA3A which are known as genes associated with cell growth, carcinogenesis, receptor activity and transcription factor. The genes expressed in the HN22 cell line treated with cyclosporin combined with $taxol^{(R)}$ were ALCAM and GTSE1 associated with cancer invasiveness and cell cycle regulation.

SINUS FLOOR GRAFTING USING CALCIUM PHOSPHATE NANO-CRYSTAL COATED XENOGENIC BONE AND AUTOLOGOUS BONE (칼슘포스페이트 나노-크리스탈이 코팅된 골이식재와 자가골을 병행 이용한 상악동 거상술)

  • Pang, Kang-Mi;Li, Bo-Han;Alrashidan, Mohamed;Yoo, Sang-Bae;Sung, Mi-Ae;Kim, Soung-Min;Jahng, Jeong-Won;Kim, Myung-Jin;Ko, Jea-Seung;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.31 no.3
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    • pp.243-248
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    • 2009
  • Purpose: Rehabilitation of the edentulous posterior maxilla with dental implants often poses difficulty because of insufficient bone volume caused by pneumatization of the maxillary sinus and by crestal bone resorption. Sinus grafting technique was developed to increase the vertical height to overcome this problem. The present study was designed to evaluate the sinus floor augmentation with anorganic bovine bone (Bio-$cera^{TM}$) using histomorphometric and clinical measures. Patients and methods: Thirteen patients were involved in this study and underwent total 14 sinus lift procedures. Residual bone height was ${\geq}2mm$ and ${\leq}6mm$. Lateral window approach was used, with grafting using Bio-$cera^{TM}$ only(n=1) or mixed with autogenous bone from ramus and/or maxillary tuberosity(n=13). After 6 months of healing, implant sites were created with 3mm diameter trephine and biopsies taken for histomorphometric analysis. The parameters assessed were area fraction of new bone, graft material and connective tissue. Immediate and 6 months after grafting surgery, and 6 months after implantation, computed tomography (CT) was taken and the sinus graft was evaluated morphometric analysis. After implant installation at the grafted area, the clinical outcome was checked. Results: Histomorphometry was done in ten patients.Bio-$cera^{TM}$ particles were surrounded by newly formed bone. The graft particles and newly formed bone were surrounded by connective tissue including small capillaries in some fields. Imaging processing revealed $24.86{\pm}7.59%$ of new bone, $38.20{\pm}13.19%$ connective tissue, and $36.92{\pm}14.51%$ of remaining Bio-$cera^{TM}$ particles. All grafted sites received an implant, and in all cases sufficient bone height was achieved to install implants. The increase in ridge height was about $15.9{\pm}1.8mm$ immediately after operation (from 13mm to 19mm). After 6 months operation, ridge height was reduced about $11.5{\pm}13.5%$. After implant installation, average marginal bone loss after 6 months was $0.3{\pm}0.15mm$. Conclusion: Bio-$cera^{TM}$ showed new bone formation similar with Bio-$Oss^{(R)}$ histomorphometrically and appeared to be an effective bone substitute in maxillary sinus augmentation procedure with the residual bone height from 2 to 6mm.

ELECTRON MICROSCOPIC STUDY OF SLOWLY ADAPTING PERIODONTAL MECHANORECEPTIVE PRIMARY AFFERENT FIBERS WITHIN THE SUBNUCLEUS ORALIS OF THE CAT (서순응형 치근막 일차구심성 신경섬유 종말부의 Subnucleus oralis에서의 시냅스 양상에 관한 전자현미경적 연구)

  • Kim, Moo-Jung;Bae, Yong-Chul;Kim, Chin-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.15 no.4
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    • pp.281-301
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    • 1993
  • It was revealed that the morphology and projection pattern of terminal arbors from single primary afferent are different among distinct fiber types, functional types and the different subdivision of trigeminal sensory nucleus complex(TSNC). But it was not identified the ultrastructural morphology and synaptic connections of terminal arbors from each primary afferent within TSNC. So we employed the intra-axonal horseradish peroxidase(HRP) injection technique to define the terminal arbors of primary afferent fiber from slowly adapting mechanoreceptors in the periodontal ligament of the cat, and examined 66 labeled terminal arbors within the rostrodorsomedial part(Vo.r) of the trigeminal nucleus oralis, electromicroscopically with 90nm serial sections. All the boutons labelled with HRP contained clear, spherical and uniform sized synaptic vesicles(diameter : $47.66{\pm}3.58nm$ ). Most of the labelled boutons were boutons en passant type and they were connected by unmyelinated axonal strand. In which neurofilament and microtubule was not developed but occasionally contained synaptic vesicle in contrast to the myelinated axon. The size of the labelled bouton was relatively small(long diameter : $1.46{\pm}0.24{\mu}m$, short diameter $0.85{\pm}0.26{\mu}m$, average diameter $1.15{\pm}0.24{\mu}m$) and the shape of which varied from dome to elongated shape, but scalloped glomerulus shape was not developed. Each primary ending in Vo.r made synapse with one or two neuronal propiles(average : $1.11{\pm}0.31$), of which, 89.4% of labelled boutons made synapse with only one neuronal pro pile, the remainder, 10.6% of labelled boutons, made synapse with two neuronal propile. So characteristically they made very simple synapse. Most of labelled boutons(80.03%) made asymmetrical synapse only with dendritic shaft or spine, and 6.1% of labelled boutons received symmetrical synapse from pleomorphic vesicle containing axonal ending(p-ending). So presynaptic inhibiton was relatively scarce. Synaptic triad, in which a p-ending is presynaptic both pre-and post-synaptic element of the axo-dendritic contact from the labelled primary ending was not observed.

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THE CLINICO-STATISTICAL ANALYSIS OF THE TREATMENT OF THE AMELOBLASTOMA (법랑아세포종의 치료에 관한 임상통계학적 분석)

  • OH, Myoung Chul;Kim, Chin Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.15 no.4
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    • pp.253-268
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    • 1993
  • The author studied on the 109 cases of ameloblastoma which had been diagnosed with biopsy during the period of 1962 to 1992 at the Kyungpook National University Hospital, Kyemyung University Hospital, Youngnam University Hospital, Catholic Medical School Hospital, Pusan National University and Maryknoll Hospital. This study contains the statistical analysis of the treatment method according to the clinicopathological findings such as sex, age, location, chief complaints, duration, radiographic findings, size and recurrence. The results were as follows : 1. The incidence rate was 59.7% in male and 40.3% in female. 2. At the time of diagnosis, the age of the patients ranged from 9 to 69 years(average 31.4years). The cases of 72.4% were in the 2nd, 3rd, and 4th decades of life. 3. The majority of cases occurred in the mandible 88.9%, especially in the mandiblar angle area 57.8%. 4. The most prevalent chief complaints was swelling 58.7%. 5. As regards duration, the cases less than 1 year appeared 49.5% and average duration is 31.34months. 6. Unilocular type showed 43.1% and multilocular type appeared 56.9%. 7. Conservative treatment was performed 39.4% and radical treatment was employed 60.6%. 8. There were variations of lesional sizes between 2.0cm and 15cm(average 6.26cm). 9. The recurrence rate is 29.4%. 10. The frequency of treatment was not in association with sexes, locations, chief complaints and sizes. 11. Radical treatment was performed more frequently in cases of older age group(above 20 years old), multilocular cases, above average duration(31.34 months) group and recurrent cases (P<0.05).

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MORPHOLOGY OF THE TERMINAL ARBORS FROM THE MASSETERIC MUSCLE SPINDLE AFFERENTS IN THE TRIGEMINAL MOTOR NUCLEUS (삼차신경 운동핵에서 교근 근방추 구심성 신경섬유 종말지의 미세구조)

  • Lee, Kyung-Woo;Bae, Yong-Chul;Kim, Chin-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.16 no.3
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    • pp.321-347
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    • 1994
  • Muscle spindle afferents from masseter muscle were labelled by the intra-axonal HRP injection and were processed for light microscopic reconstruction. Regions containing terminal arbors scattered in the central portion of the masseteric motor neuron pool (type I a) and those restricted to 2-3 small portion of it (type II) were selected and processed for electronmicroscopic analysis with serial sections. The shape of the labelled boutons was dome or elongated shape. Scalloped or glomerulus shape with peripherial indentation containing pre or postsynaptic neuronal propiles, which is occasionally found in the trigeminal main sensory nucleus and spinal dorsal horn, was not observed. Both type Ia and type II boutons had pale axoplasm and contained clear, spherical vesicles of uniform size(dia : 49-52nm) and occasionally large dense cored vesicles(dia : 87-118nm). The synaptic vesicles were evenly distributed throughout the boutons although there was a slight tendency of vesicles to accumulate at the presynaptic site. The average of short and long diameter(short D. + long D./2) of type I a bouton was smaller than that of type II bouton. All the labelled boutons, which showed prominent postsynaptic density, large synaptic area and multiple synaptic contact, made asymmetrical synaptic contact with postsynaptic neuronal propiles. Most of the type Ia and type II boutons made synaptic contact with only one neuronal propile and boutons which shows synaptic contact or more neuronal propiles was not observed. Most of the type Ia boutons(87.2%) were presynaptic to the soma or proximal dendrite and a few remainder(12.8%) made synaptic contact with dendritic shaft or distal dendrite. In contrast, majority of type II boutons showed synaptic contact with dendritic shaft and remainder with soma or proximal dendrite. In conclusion, terminal boutons which participate in the excitatory monosynaptic jaw jerk reflex made synaptic contact with more proximal region of the neuron, and showed very simple synaptic connection, compared with those from the primary afferenst in the other region of the central nervous system such as spinal dorsal horn and trigeminal main sensory nucleus which assumed to be responsible for the mediating pain, tactile sensation, sensory processing or sensory discrimination.

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