• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제30권4호
• /
• pp.345-352
• /
• 2008

Purpose: This study was performed to evaluate the stress distribution in the bone and the displacement distribution of the miniscrew under orthopedic force with two different types of miniplate design as skeletal anchorage for orthopedic treatment. Materials and methods: Finite element models were made for 6-hole miniplate (0.8mm in thickness), which were designed in two different shapes-one is curvilinear shaped (C plate, Jeil Medical Co., Korea) and another, Y shaped (Y plate), fixed with 3 pieces of miniscrew 2mm-diameter and 6mm-long respectively. A traction force of 4 N was applied in $0^{\circ}$, $30^{\circ}$ and $60^{\circ}$ to imaginary axis connecting two unfixed distalmost holes of the miniplate. Results: The maximum von Mises stress in the bone was much greater in the cortical portion rather than in the cancellous portion. C plate showed greater maximum von Mises stress in the cortical bone than Y plate. The maximum displacement of the miniscrew was greater in C plate than Y plate. The more increased the angle of the applied orthopedic force, the greater maximum von Mises stress in the bone and maximum displacement of the miniscrew. It was observed that in C plate, the von Mises stress in the bone and displacement of the miniscrew were distributed around the distalmost screw-fixed area. Conclusions: The results suggest that Y plate should have the advantage over C plate and in the placement of the miniplate, its imaginary axis should be placed as parallel as possible to the direction of orthopedic force to obtain its primary stability.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제31권2호
• /
• pp.149-157
• /
• 2009

Purpose: This study was to evaluate the validity of superimposition range at facial images constructed with 3-dimensional (3D) surface laser scanning system. Materials and methods: For the present study, thirty adults, who had no severe skeletal discrepancy, were selected and scanned twice by a 3D laser scanner (VIVID 910, Minolta, Tokyo, Japan) with 12 markers placed on the face. Then, two 3D facial images (T1-baseline, T2-30 minutes later) were reconstructed respectably and superimposed in several manners with $RapidForm^{TM}2006$ (Inus, Seoul, Korea) software program. The distances between markers at the same place of face were measured in superimposed 3D facial images and measurement were done all the 12 makers respectably. Results: The average linear distances between the markers at the same place in the superimposed image constructed by upper 2/3 of the face was $0.92{\pm}0.23\;mm$, in the superimposed image constructed by upper 1/2 of the face was $0.98{\pm}0.26\;mm$, in the superimposed image constructed by upper 1/3 of the face and nose area was $0.99{\pm}0.24\;mm$, in the superimposed image constructed by upper 1/3 of the face was $1.41{\pm}0.48\;mm$, and in the superimposed image constructed by whole face was $0.83{\pm}0.13\;mm$. There were no statistically significant differences in the liner distances of the makers placed on the area included in superimposition range used for partial registration methods but there were significant differences in the linear distances of the markers placed on the areas not included in superimposition range between whole registration method and partial registration methods used in this study. Conclusion: The results of the present study suggest that the validity of superimposition is decreased as superimposition range is reduced in the superimposition of 3D images constructed with 3D laser scanner for the same subject.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권4호
• /
• pp.337-345
• /
• 2011

Purpose: The purpose of this study was to define the relation of the degree of menton deviation and 3-D CT (computerized tomography) measurements of the glenoid fossa and the mandible, which are considered to have an influence on menton deviation. Methods: The CT images were obtained in 60 adults and these were transmitted to a computer and reconstructed using computer software. According to the degree of the menton deviation, which was measured on the posteroanterior cephalogram, the subjects were divided into the menton deviated group (30 adults) and the symmetry group (30 adults). A total of 11 measurements that might have an effect on menton deviation were determined and these were measured in the right and left sides using the function of 3-D measurement in the computer program. The 11 measurements consist of 6 measurements in the glenoid fossa (vertical position of the glenoid fossa and articular eminence, the sagittal position of the glenoid fossa and articular eminence, the depth of the glenoid fossa, and the anterior angle of the glenoid fossa), and 5 measurements in the mandible (ramus length, frontal ramal inclination, lateral ramal inclination, body length, body height). Results: The comparison of the differences between the menton deviated and symmetry groups and correlation analysis on the degree of menton deviation were carried out. The results of comparison of the right and the left difference between the menton deviated and symmetry groups showed that the vertical position and depth of the glenoid fossa were significantly increased in the menton deviated group. Conclusion: The results of the present study show that consideration of the shape and position of the glenoid fossa is necessary for making the diagnosis and administering proper treatment in facial asymmetry patients and especially growing patients.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제37권
• /
• pp.32.1-32.5
• /
• 2015

Background: The aims of present study were (1) to evaluate new bone formation among the 4-hexylresorcinol (4HR)-incorporated silk fabric membrane (SFM), conventional SFM, and uncovered control groups and (2) to compare the amount of residual membrane between the 4HR-incorporated SFM and conventional SFM in a rabbit parietal defect model. Methods: Nine New Zealand white rabbits were used for this animal study. After the formation of a bilateral parietal bone defect (diameter 8.0 mm), either 4HR-incorporated SFM or conventional SFM was grafted into the defect. The defect in the control was left uncovered. New bone formation and the amount of residual membrane were evaluated by histomorphometry at 8 weeks after the operation. Results: The total amount of new bone was $37.84{\pm}8.30%$ in the control, $56.64{\pm}15.74%$ in the 4HR-incorporated SFM group, and $53.35{\pm}10.52%$ in the conventional SFM group 8 weeks after the operation. The differences were significant between the control and 4HR-incorporated SFM group (P = 0.016) and between the control and conventional SFM group (P = 0.040). The residual membrane was $75.08{\pm}10.52%$ in the 4HR-incorporated SFM group and $92.23{\pm}5.46%$ in the conventional SFM group 8 weeks after the operation. The difference was significant (P = 0.039). Conclusions: The 4HR-incorporated SFM and conventional SFM groups showed more bone regeneration than the control group. The incorporated 4HR accelerated the partial degradation of the silk fabric membrane in a rabbit parietal defect model 8 weeks after the operation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권6호
• /
• pp.432-439
• /
• 2012

Purpose: The aim of this study was to investigate the blood supply to the maxillary sinus in Koreans using computed tomography of the lateral wall of the sinus, and to analyze the data according to demographic data, and to compare our results with previously published research. Methods: One hundred and three patients (males 51, females 52) who visited the dental clinic were evaluated. We investigated the canals with cone-beam computed tomography, and measured the diameter and length from the bony notch of the vascular canal at the lateral wall of the sinus to each of the reference planes. Results: Most types of vascular canal were type I & II (total 72.2%) which were driving through inside the sinus wall. Type IV, V were frequently investigated in 1st premolar and 2nd molar. Mean height; from anterior nasal spine-posterior nasal spine plane to vascular canal was 5.56 mm in 1st premolar, 2.11 mm in 2nd premolar, 0.98 mm in 1st molar, 4.32 mm in 2nd molar; from the basal layer of the sinus was 4.93 mm in 1st premolar, 5.00 mm in 2nd premolar, 6.05 mm in 1st molar, 7.91 mm in 2nd molar; and from alveolar crest, 20.80 mm in 1st premolar, 16.57 mm in 2nd premolar, 14.01 mm in 1st molar, 16.17 mm in 2nd molar. The mean height of the vascular canal of each reference plane showed no significant difference between sex, site (left or right) and age. The mean diameters of the canals were 1.76 mm in male, and 1.50 mm in female. Diameter decreased with age, and tooth site (from 1st premolar to 2nd molar). Conclusion: These results show that the mean diameter of the vascular canal of the maxillary sinus varies according to age, sex, and tooth site, but that the mean height of canal had no significant difference based on these three factors.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제11권1호
• /
• pp.50-62
• /
• 1989

저자는 1982년 1월부터 1987년 12월까지 대구시내 주의료기관인 5개 종합병원에 입원가료한 바 있는 하악골 골절환자 677명을 대상으로 임상적 연구를 시행한 바 다음과 같은 결과를 얻었다. 발생빈도에 있어서 연도별로는 약간의 증가추세에 있었고, 월별로는 5월과 9월에 호발하였고 지역별로는 대구시(55.7%)가 많았으며 대도시 (63.0%)에서 다소 높았다. 연령별 및 성별에서 20대(38.3%)에서 가장 호발하였으며 10대(18.5%), 30대 (18.0%)의 순으로 나타났으며 남녀비는 4.64 : 1로서 남자에게서 호발하였다. 원인별로 볼때 구타(31.5%), 교통사고 (29.5%)와 추락(15.2%), 전도(15.1%)로 많은 비중을 나타내었으며,별로 보면 20-40시 사이에 구타가 가장 많았다. 골절부위별로는 하악골 단독골절이 95.5%였으며 중안면골 골절이 동반된 경우가 4.5%였으며 골절 부위 수는 총 1,033개로서 1인당 평균 1.53개였으며 정중부(39.8%), 우각부(25.2%), 과두부(22.7%)의 순이었으며 정중부를 제외한 좌우측 비교에서 좌측이 364례로서 우측의 257례보다 많았다. 수상후 24시간이내에 전체의 62.9%가 내원하였으며, 1차 진료기관을 거친 경우가 42.4%였으며 유형별로는 일반의원(44.6%), 일반병원(27.9%) 및 치과의원(25.4%)의 순으로 나타났다. 처치내용별로는 관혈적정복수술이 전체의 55.0%를 차지하였고 37.2%는 비관혈적 정복수술을 받았으며, 소아에서는 주로 비관혈적 정복수술이 50.6%를 차지하였다.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제14권4호
• /
• pp.295-304
• /
• 1992

The author investigated the 162 patients with the condylar fractres of the mandible who were admitted in Dept. of Oral and Maxillofacial Surgery, Hospital of Chosun Dental School from January 1985 to September 1992 clinically, including fracture incidennce, age and sex of the patients, causes of injures, associated injures, treatments and complications and obtained the following results. 1. Of the 449 patients with mandibular fractures, 162patients suffered condylar fractures(36.1%). 2. Of the 162 patients, males with condylar fractures were 128 patients, by a ratio of 3.8 : 1. 3. The most frequently affected age group was the third decade(32.7%). 4. Falls were ranked as the predominant cause(50.6%), followed by traffic accident(27.8%) and violence (16.0%). 5. The incidence of single condylar fractures was 28% and symphysis fractures were the most commomest of the concomittant injuries(60%). 6. The subcondylar fractures occurred most frequently(41.6%) and anteromedial displacement of the condylar fragments occurred most frequently(45.4%) 7. Of the all condylar fracture patients, children under 15 of age comprized 31 patients(19.1%) and condylar head fractures occurred most frequently at those children. 8. Of the managetments in condylar fractures, open reduction was 52.5% and remainder were closed reduction(47.5%). 9. Complications ensured such as TMJ ankylosis, limitation of mouth opening and mandibular movements, TMJ dysfunction, and anterior open bite.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제18권2호
• /
• pp.224-235
• /
• 1996

Early implantation before sufficient ossification has taken place usually results in osseointegartion failure due to reduced bone-fixture interface area. However, various studies have shown successful osseointegration results following immediate implants concurrently with GTR. The clinical trends have been to shorten the patients' edentulous state by immediate implantation, and reduce the alveolar bone resorption. However, it may be difficult to attain the complete soft tissue coverage of the sites, increasing the chance of infection. Furthermore, there may be more studies needed on the clinical behaviors of e-PTFE membranes, various modofications in the membrane materials and bone graft materials. Various animal and clinical studies have been reported on the successful osseointagration following immediate implantation, but the long-term follow-up studies are limited. The present study investigated 16 immediately-implanted implants with GTR therapy with or without calcium carbonate grafting on 11 patients 3 years after installation and 24-30 months after functional loading. Based on the clinical, radiographic and histologic findings, the following results have been attained. 1. Clinically, stability has been shown on all 16 implants throughout the investigated periods. 2. Radiologically, the alveolar bone loss has progressed up to the polished neck portion but not beyond it, suggesting the progressive osseointegration from the GTR therapy. 3. The GTR method used in the present study is easy to use clinically, and may be appied in the regeneration of ossoeous defects around implants and in the immediate implantation. 4. The difficulty in complete tissue coverage may be avoided by delaying the installation for 2 to 3 weeks after the extraction allowing certain degree of soft tissue healing.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제13권1호
• /
• pp.1-8
• /
• 1991

체중 100g 내외의 Sprague Dawley계 정상백서 암, 수 각 50마리씩을 실험동물로 하여 분말형태의 순수 DMBA를 소구(pellet)로 압착제작하여 우측 악하선에 매식후 즉시, 1,3,5,7,9,11,13,15,17주째 10마리씩 희생시켜 좌, 우측악하선을 적출, 무게를 측정하고, 육안적, 조직학적, 생화학적으로 실험기간에 따라 비교분석하여 다음과 같은 결론을 얻었다. 1. 매식후 11 주째부터 우측 경부 악하선부위의 종창을 관찰할 수 있었으며, 결절덩어리를 촉진할 수 있었다. 2. 우측악하선의 무게의 크기는 실험기간의 경과에 따라 괄목할만한 증가를 보였다(매식후 17주째는 좌측에 비해 약 5.5배의 무게를 나타냈다). 3. 매식후 7주와 11주째부터 조직학적으로 상피이형성과 침윤성 유표피암의 소견을 각각 관찰할 수 있었다. 4. 우측 악하선에서의 유표피암의 발생율은 매식후 17주째 76%이었다. 5. DMBA 는 현저히 억제된 $Na^+,K^+$-ATPase 활성도를 야기하며 실험기간의 경과의 따라 활성도 비율도 현저히 저하시킨다.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제15권3호
• /
• pp.217-228
• /
• 1993

The purpose or this study was to observe the histological alteration of Langerhans cells on wound healing process in applying low energy laser irradiation. For this study, 50 Spraque-Dewly rats, weighing 150Gm or more were devided into control, experimental control group(0), 47.5Hz(1), 190Hz(3), 380Hz(5), 760Hz(7), lased group. All the experimental animals were made excision wound on buccal mucosa, 2mm depth, and lased with stoma laser (904nm, semconductor type ASGaAI, Sedalac France) 47.5Hz, 380Hz, 960Hz, 3minutes one time respectively except experimental control group. After the experiment, experimental animals were sacrificed after 24hours, 48hours, 72hours on each. Taken specimens were embedden in paraffin, sectioned 6-8u in thickness. And the langerhans cell were detected using ant S-100 protein antibody, and histochemically processed with Avidin Biotin complex method. All the Langerhan cells were calculated under light microspe in 400 multiplication field and standard deviation, probability test between each group were evaluated using statistical analysis system(S.A.S)program. Following results were obtained. 1. Langerhan cells were increased in experimental control group compared to that in control group(P<0.01). 2. 24hour after experiments, Langerhans cell were decreased compare to that in control group and control experimental group 5, 1, 3. Probability test shows significance between control experimental and 5, 1, 3 group on a =0.05 range. 3. 48our after experiment, Langerhans cells were decreased compare to that on experimental control group, and probability test shows significance between control experimental and 3, 7, 5 group an a=0.05 range. 4. 72hour after experiments, Langerhans cells were decreased compare to that on experimental control group and probability test on group comparison shows significance between control experimental and 1, 5 and 1 between 3, 7 between 3, and 5, between 7, respeilively on a=0.05 range. 5. Langerhans cells number in experimental group were decreased compare to that on experimental control group in applying laser irradiation.