• Archives of Plastic Surgery
• /
• v.35 no.1
• /
• pp.104-106
• /
• 2008

Purpose: Fewer than 100 cases of calcifying aponeurotic fibroma have been reported in the literature since this entity was initially described by Keasbey in 1953 who called it calcifying juvenile aponeurotic fibroma. The tumor is a slowly growing, painless mass. In most cases the mass is poorly circumscribed and causes neither discomfort nor limitation of movement. Most lesions occur in children, with a peak incidence ages of 8-14 years. There is no evidence of any increased familial prevalence. Predilection sites are palm, finger, toe, but it also occurs in the wrist, forearm, elbow, upper arm, neck, abdominal wall, lumbar paravertebral area, leg and ankle. We herein describe a rare case of calcifying aponeurotic fibroma occurring on the chin with review of the literature. Methods: A 14-year-old male had painless, slowly growing mass(${\phi}2.5cm$) on a chin for a year. The tumor was excised elliptically under local anesthesia and the excisional site was repaired directly. Due pathological examination was processed. Results: Histological examination revealed an illdefined fibrous growth that extends with multiple processes into the surrounding tissue with centrally located foci of calcification. The tumor is composed of short spindled plump fibroblasts with round or ovoid nuclei separated by collagenous stroma, showing vaguely palisading pattern. Diagnosis of calcifying aponeurotic fibroma was conferred. Postoperatively, the patient did well, and the lesion had not recurred. Conclusion: Fewer than 100 cases of calcifying aponeurotic fibroma have been reported in the literature. The most common occurring sites are palm, finger & toe, but it has been reported in the wrist, forearm, elbow, upper arm, neck, abdominal wall, lumbar paravertebral area, leg and ankle. Two cases of calcifying aponeurotic fibroma occurring on the neck have been reported in the literature. To the authors knowledge, our case of calcifying aponeurotic fibroma occurring on the chin is the first to be reported.

• Archives of Craniofacial Surgery
• /
• v.23 no.3
• /
• pp.103-110
• /
• 2022

Background: The primary objectives of mandibular surgery are to achieve optimal occlusion, low sensory disturbance, and adequate fixation with early movement. In-depth knowledge of the mandibular structure is required to achieve these goals. This study used computed tomography (CT) to evaluate the mandibular cortical thickness and cancellous space according to age and sex. Methods: We enrolled 230 consecutive patients, aged 20 to 50 years, who underwent CT scanning. The cortex and cancellous space centered around the inferior alveolar nerve (IAN) canal were measured at two specific locations: the lingula and second molar region. Statistical analysis of differences according to increasing age and sex was performed. Results: The t-test revealed that the cancellous space and cortical thickness differed significantly with respect to the threshold of 35 years of age. Both cortical thickness and cancellous space in the molar region were negatively correlated with age. Meanwhile, both cortical thickness and cancellous space in the lingula region showed a positive correlation with age. With respect to sex, significant differences in the cancellous space at the molar region and the cortical thickness at the lingula were observed. However, no further statistically significant differences were observed in other variables with respect to sex. The sum of each measurement on the mandibular body reflected the safe distance from the surface of the outer cortex to the IAN canal. The safe distances also showed statistically significant differences between those above and below 35 years of age. Conclusion: Knowledge of the anatomical structure of the mandible and of changes in bone structure is crucial to ensure optimal surgical outcomes and avoid damage to the IAN. CT examination is useful to identify changes in the bone structure, and these should be taken into account in the planning of surgery for older patients.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1990.10a
• /
• pp.111-128
• /
• 1990

Three numerical analysis carried out for the design of a diaphragm wall were examined by the results of field observation data. Utilizing the wall stiffness, supporting system and construction sequence, the relative merits of those factors on the analysis of diaphragm wall have been investigated and their effects are compared tilth the observed behaviour of the wall. The predicted bending moment and wall displacement by elasto-plastic method agreed well with the observed values. The rigid slab supported system (i.e Top-Down Method) found to be the most effective way of controlling ground movement.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1995.03a
• /
• pp.155-161
• /
• 1995

Superplastic forming/diffusion bonding(SPF/DB) processes are analyzed using a rigid visco-plastic finite element method. The optimum pressure-time relationship for a target strain rate and thickness distributions were predicted using two-node line element based on membrane approximation for plane strain shapes. Material behavior during SPF/DB of the integral structures with complicated shapes are investigated. The tying condition is employed for the analysis inter-sheet contact problems. A movement of rib structure is successfully prodicted during the forming.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.33 no.5
• /
• pp.413-419
• /
• 2011

Purpose: Reposition of the maxilla is a common technique for correction of midfacial deformities. To achieve the goal of the surgery, the maxilla should be repositioned based on the precisely planned position during surgery. The internal reference points (IRPs) and the external reference points (ERPs) are usually used to determine vertical dimension of maxilla, which is an important factor for confirming maxillary position. However, the IRPs are known to be inaccurate in determining the vertical dimension. In this study, we investigated the correlation of positional change of the modified IRPs with repositioned maxilla. Methods: The study group consisted of 26 patients with dentofacial deformities. For the simulation of the surgery, patient maxillary CT data and 3-D virtual surgery programs (V-$Works^{(R)}$ and V-$Surgery^{(R)}$) were used. IRPs of this study were set on both the lateral wall of piriform aperture, inferior margin of both infraorbital foramen, and the labial surfaces of the canine and first molar. The distance from the point on lateral wall of the piriform aperture to the point on the buccal surface of the canine was defined as IRP-C, and the distance from the point on the inferior margin of the infraorbital foramen to the point on the buccal surface of the $1^{st}$ molar was defined as IRP-M. After the virtual simulation of Le Fort I osteotomy, the changes in IRP-C and IRP-M were compared with the maxillary movement. All measures were analyzed statistically. Results: With respect to vertical movements, the IRP-C (approximately 98%) and the IRP-M (approximately 96%) represented the movement of the canine and the $1^{st}$ molar. Regarding rotating movement, the IRPs changed according to the movement of the canine and the $1^{st}$ molar. In particular, the IRP-C was changed in accordance with the canine. Conclusion: IRPs could be good indicators for predicting vertical movements of the maxilla during surgery.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.22 no.2
• /
• pp.191-205
• /
• 2000

The purpose of this study was undertaken to determine the effects of orthognathic surgery on speech. The hyposis stated herein is that functional behaviors of the dentofacial complex, such as speech production, may be adversely affected by deviations of a structural nature(especially, Class III malocclusion). Twenty adults with Class III malocclusion(13 female and 7 male) were studied preoperative, immediate postoperative and either 6 or 12 months postoperative lateral cephalograms. They had mandibular prognathism and had undergone mandible setback operation. The position of tongue, soft palate(Uvula), hyoid bone, respiratory track width, and pharyngeal depth were assessed on lateral cephalograms with 23 cephalometric variables, ANOVA, Paired t-tests and Pearson's product-moment correlation coefficient tests were used to evalute the operative changes in all cephalometric parameters. A experienced speech and language pathologists performed narrow phonetic transcriptions of tape-recorded words and sentences produced by each of the ninth patients and the recording tapes were analyzed by phonetic computer program(Computerized Speech Lab(CSL) Model 4300BI(U.S.A.)) These judges also recorded their ratings of each patient's overall consonants, hypernasality, hyponasality, and articulation proficiency. The results obtained are as follows; 1. There were significant changes in distance of posterior pharyngeal wall to tongue (TI-TW2, TS-TW3) after the surgery at 6 months postoperatively(each p<0.01 p<0.05). 2. The posterior tongue point(TI, TS, PPT) moved posteriorly after surgery and remained to its changed position at 6 months postoperatively(p<0.05). The displacement of tongue was correlated with the movement of mandibular setback amount(p<0.05). The hyoid bone moved posteriorly superiorly after immediate postoperative period. There was significant changes in hyoid bone movement after immediated postoperative period(p<0.05), but returned to its original position during the follow-up period(p>0.05) 3. The soft palate was displaced posteriorly superiorly after immediated operative period and remained to its changed position at 6 months postoperatively(p<0.05). ANS-PNS-SPT angle increasing, PPU-PPPo distance narrowing was showed after surgery, and remained its appearance 6 months postoperatively(p<0.05). 4. There were significant changes in formant value and squre diagram of vowel sound after the orthognathic surgery and the follow-up period. There were significant changes in /ㅅ/sound and posterior tongue sound. 5. The posterior movement of tongue and the posteriosuperior movement of soft palate was correlated with mandibular setback amount after orthognathic surgery. On the vowel squre diagram, the author found that the place of articulation after operation moved downward, backward, upward. 6. In assessing speech abnormalities, dental occlusion should be considered as a contributing factor. The vast majority of subjects with preoperative misarticulations eliminated or reduced their errors following orthognathic surgery. There was significant difference in speech impovement between pre- and postoperation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.34 no.6
• /
• pp.413-420
• /
• 2012

Purpose: The purpose of this setback genioplasty study is to develop a prediction method for the calculated osteotomy angle using horizontal and vertical changes as well as to evaluate the proportion of hard and soft tissue changes. Methods: Twelve patients who had received setback genioplasty with other maxillofacial surgery were examined. Three lateral cephalograms were taken just before surgery, immediately after surgery, and 3 months later surgery. A reference line was established to the reference point of the inner most point of the lingual symphysis cortex, incisor tip, and 2nd molar cusp tip. Measuring was conducted from pogonion (Pg), menton (Me), labrale inferius (Li), Mentolabial fold, soft tissue pogonion (Pg'), and soft tissue menton (Me') to the reference lines. Results: In setback genioplasty, the skeletal Pg moved posteriorly 5.07 mm. The ratios of soft tissue to hard tissue movement were 36% posteriorly and 62% inferiorly at Pg', 67% posteriorly and 104% inferiorly at Me', and 34% anteriorly and 164% posteriorly at Li. In reduction & setback genioplasty, skeletal Pg moved posteriorly 4.63 mm and skeletal Me moved superiorly 3.63 mm. The ratios of soft tissue to hard tissue movement were 76% posteriorly and 18% superiorly at Pg', 68% posteriorly and 42% superiorly at Me', and 44% anteriorly, 124% posteriorly at Li. The calculated mean slope angle, based on ${\Delta}H/{\Delta}V$ ratio, was 61.25 and the measured mean slope angle was 60.17. Thus, the calculated and measured slope angles have a similarity. Conclusion: In setback genioplasty, soft tissue moves posteriorly and inferiorly. In particular, at the Me' and Pg', the inferior movement of the soft tissue is greater than the posterior movement. Also, the predictable results (measured slope angle) after operation can be achieved by the calculated slope angle. Thus, the relationship of soft and hard tissue changes must be considered as the results are predictable.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.6
• /
• pp.1405-1415
• /
• 1994

The soil on the behavior of the nonlinear elastic work-hardening plasticity has a variety of stress paths due to the state of soil and the test conditions. The soil with a specific volume ${\upsilon}$ in principal stress space (${\sigma}_1$, ${\sigma}_2$, ${\sigma}_3$, and ${\upsilon}$v) displays the shape of an irregular hexagonal pyramid with an end cap. With variations of ${\upsilon}$ the size of the cap is changed but its shape remains unchanged and the movement of the cap is controlled by the increase or decrease of the plastic volumetric strain. By reflecting such a property of soil various cap models have been developed by researchers. In this thesis, a constitutive model of soil with a combination of the nonlinear elastic work-hardening plastic cap and the failure surfaces of Mohr-Coulomb (M-C cap model) has been developed. According to the the results of analyses using the work-hardening plastic cap model, the normally consolidated soil under shearing has experienced the work-hardening and plastic flow (movement of the cap). But in the shearing of the overconsolidated soil the elastic behavior is shown until the stress path has reached the failure surface and the cap does not move.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.19 no.2
• /
• pp.117-129
• /
• 1997

Recently, combined with social complexity, increment of medical demand and supply and the change of esthetic category, admission and operation of the patients of facial deformity have been changed with annual change. This study was conducted in the concept of helping the overall character of orthognathic surgery in future understood and being an important index in the establishment of better treatment course, through the patient, on whom was operated orthognathic surgery via sagittal split ramal osteotomy in our Dept. of Oral & Maxillofacial Surgery, Chonbuk National University Hospital from 1991. 1. 1 to 1995. 12. 31. The results were obtained as follows. 1. The ratio of male to female was 1 : 1.33 and the ages between 16 and 25 year was 73.6%, and the mean age was 20.4 years. 2. The ratio of setback amount between 6 to 15mm was 84.6% and the advancement amount between 1 to 10mm was 89% and the mean amount of movement was 9.0mm in setback, and 3.6mm in advancement. 3. After removal of maxillomandibular fixation(MMF), the distinction of sex was not statistically significant in ROM. 4. The ROM following methods of fixation was statistically significant in 3rd(P<0.05), 8th, and 12th week(each P<0.01), with faster rehabilitation in rigid fixation which had shorter MMF period. 5. The rehabilitation of ROM following the operation methods was statistically significant in 1st(P<0.05), 2nd, 3rd, 4th, 6th, 8th, and 12th week(each P<0.01) with faster rehabilitation in the case of SSRO than Lefort I / SSRO (Two jaw surgery). 6. The rehabilitation of ROM following directions of mandibular movement did not manifest a statistically significant difference in both setback and advancement.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.36 no.5
• /
• pp.185-191
• /
• 2014

Purpose: Although there have been several studies of reduced airway space after mandibular setback surgery using the sagittal split ramus osteotomy technique, research on the risk factors for changes of the airway space is lacking. Therefore, this study was performed to examine airway changes and the position of the hyoid bone after orthognathic surgery, and to assess possible risk factors. Methods: In this retrospective study, 50 patients who underwent posterior displacement of the mandible by the bilateral sagittal split ramus osteotomy technique were included. Changes of the position of the hyoid bone and the airway space were analyzed over various follow-up periods, using cephalometric radiography taken preoperatively, immediately after surgery, eight weeks after surgery, six months after surgery, and one year after surgery. To identify risk factors, multiple regression analysis of age, gender, body mass index (BMI), posterior mandibular movement, and the presence of genioplasty was performed. Results: Inferor and posterior movement of the hyoid bone was observed postoperatively, but subsequent observations showed regression towards the anterosuperior aspect. The airway space also significantly decreased after surgery (P<0.05), and increased slightly up until six months after surgery. The airway space significantly decreased (${\beta}=0.47$, P<0.01) as the amount of mandibular setback increased. However, age, sex, BMI, and presence of genioplasty were not associated with airway reduction. Conclusion: The amount of mandibular set back was significantly associated with postoperative reduction of airway space. It is necessary to establish a treatment plan considering this factor.