1.A Study on the Relation between Delaire's Ideal Occlusal Plane and Masticatory Muscle Activity in Korean Normal Angle Class I Occlusion Individuals.
Seong Kyu BYUN ; Choong Kook YI
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2000;26(3):229-237
According to the functional matrix theory, Delaire proposes that individual occlusal plane was determined by variable effects of teeth, maxilla, mandible, cranium, cranial base and soft tissue matrix including the orofacial musculature. and that there is the ideal occlusal plane determined by the most proper spatial position of maxilla and mandible, functionally and esthetically. This study was designed to find out the relation between Delaire's ideal occlusal plane and muscle activity of masticatory muscles in individuals who have normal maxillo-mandibular relationships. Lateral cephalometric radiographs were taken and his/her individual occlusal plane and ideal occlusal plane were analyzed with Delaire's architectural and structural craniofacial analytic method. For evaluation of muscle activities of masticatory muscles, electromyography of anterior temporal muscle, superficial masseter muscle, and anterior belly of digastric muscle was recorded in fifty Korean normal Angle class I occlusion individuals. According to the average value of ideal occlusal plane, fifty normal Angle class I occlusion individuals were classified into three groups: Ideal occlusal plane group(I group), hyperrotation group(I+ group) and hyporotation group(I-group). The result of this study was as follows: 1. The results of Delaire's architectural and structural craniofacial analysis of lateral cephalography of the fifty Korean normal Angle class I occlusion individuals are that twelve persons(24%) have consistent or parallel with ideal occlusal plane and the average of angular difference was 1.22 degrees +/-3.69 degrees. 2. There is no significant difference in muscle activities of masticatory muscles during resting(p<0.05), but significant increases of muscle activity of ipsilateral anterior temporal and masseter muscle, contralateral anterior belly of digastric muscle during unilateral chewing and of anterior temporal and masseter muscle during bilateral clenching(p<0.05). 3. To find out the effect of the angular difference between Delaire's ideal occlusal plane and real occlusal plane to muscle activity, muscle activities of masticatory muscles were compared with three groups in each other; I group, I+ group and I-group. The results were no significant differences during resting, unilateral chewing and bilateral clenching.(p>0.05) 4. Although there is no significant differences of masticatory muscle activities among the three groups, the fact that increasing tendency of masseter muscle activity of ideal occlusal plane group(I+) than those of any other groups(I+ and I-) during bilateral clenching was noted. There is only the implication that occlusal plane makes some effects on masticatory muscle activities, espacially that of masseter muscle during bilateral clenching. In conclusion, the hypothesis that occlusal plane is one of the factors which affect the muscle activities of masticatory muscles and that anyone whose occlusal plane consistent with Delaire's ideal occlusal plane has an extraordinary functional advantage in masticatory muscle function cannot be proven with electromyography methods.
Dental Occlusion*
;
Electromyography
;
Malocclusion, Angle Class I*
;
Mandible
;
Masseter Muscle
;
Mastication
;
Masticatory Muscles*
;
Maxilla
;
Skull
;
Skull Base
;
Temporal Muscle
;
Tooth
2.Mandibulotomy, A Surgical approach for Oral cancer: Its Complications and contributing factors.
Seong Kyu BYUN ; Eun Chang CHOI ; Won Se PARK ; Eui Woong LEE ; In Ho CHA
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2000;26(4):422-426
We reviewed 56 patients who received mandibulotomy at Yonsei medical center between 1989 and 1999. We also analysed the complications associated with mandibulotomy and its contributing factors. The complications occur in 16 patients(28.6%) and are classified into two categories; intraoperative and postperative complications. Nonunion was observed in 5 patients and osteoradionecrosis in 5. The patients who received preoperative radiation therapy were more tend to develop nonunion and osteoradionecrosis. This study suggests the benefits of mandibulotomy as a surgical approach to oral cancer: 1. Paramedian osteotomy was recommended for preservation of neurovascular bundle and ease of surgical access. 2. By using thin saw blade, reapproximation was improved with minimal bone loss. 3. osteotomy on anterior mandible which lies outside the usual portals of radiation therapy decreases the incidence of osteoradionecrosis.
Humans
;
Incidence
;
Mandible
;
Mouth Neoplasms*
;
Osteoradionecrosis
;
Osteotomy
3.Prognostic Significance of the Tumor Volume and Tumor Percentage for Localized Prostate Cancer.
Jae Seung CHUNG ; Byoung Kyu HAN ; Seong Jin JEONG ; Sung Kyu HONG ; Seok Soo BYUN ; Gheeyoung CHOE ; Sang Eun LEE
Korean Journal of Urology 2008;49(12):1074-1080
PURPOSE: Tumor volume has been thought to be an important predictive factor for significant prostate cancer. We assessed the impact of the tumor volume(TV) and the tumor percentage(TP) of radical prostatectomy specimens on the pathological variables and the oncological outcome. MARERIALS AND METHODS: The tumor percentage and tumor volume were calculated for 525 cases by a single pathologist who determined the volume based on the surface area of the slides involved by tumor of the prostate. Univariate and multivariate logistic regression analyses were used to characterize the association of TP categories(<5%, 5-10%, 11-20% and >20%) and TV(<1.8cc, 1.8-3.7cc, 3.8-7.5cc, >7.5cc) with the clinicopathological variables. Biochemical recurrence(BCR) was estimated using Kaplan-Meier analysis and Cox's hazard regression model. RESULTS: The mean prostate cancer volume was 6.5+/-8.5cc(median: 3.8, range: 0.04-73.8) and the mean percent tumor composition was 0.17+/-0.19 (median: 0.1, range: 0.01-0.95). A higher tumor volume and a higher tumor percentage were associated with extra-capsular extension(ECE), a positive surgical margin(PSM), a higher pT stage and a higher prostate-specific antigen(PSA) Gleason score(all p<0.05). In addition, TP was the independent predictor of ECE(adjusted odds ratio(OR): 22.66, 95% confidence interval(CI): 1.801-285.079, p=0.016), but the tumor volume was not associated with ECE on the multivariate logistic analyses. On the Kaplan-Meier analysis, but not on the Cox-hazard analyses, the TP did demonstrate a significant association with biochemical recurrence(p=0.035), yet the TV did not reach statistical significance(p=0.190). CONCLUSIONS: Our data indicates that the tumor percentage had a significant effect on the BCR on the Kaplan-Meier analysis. The tumor percentage rather than the tumor volume might be more useful to predict the prognosis of prostate cancer.
Kaplan-Meier Estimate
;
Logistic Models
;
Prognosis
;
Prostate
;
Prostatectomy
;
Prostatic Neoplasms
;
Recurrence
;
Tumor Burden
4.Are Risk Factors for Failure after Mid-Urethral Sling Operation Different between Patients with Pure Stress and Those with Mixed Urinary Incontinence in the Short-Term Follow-Up?.
Seong Jin JEONG ; In Sik HWANG ; Seong Soo KIM ; Seung Tae LEE ; Kyung Eun MIN ; Byung Kyu HAN ; Sung Kyu HONG ; Seok Soo BYUN ; Sang Eun LEE
Korean Journal of Urology 2009;50(6):573-580
PURPOSE: Although application of the mid-urethral sling (MUS) operation has expanded to more complicated cases such as patients with mixed urinary incontinence (MUI), the success rates in patients with MUI have been reported to be lower than those in patients with pure stress urinary incontinence (SUI). We evaluated and compared the risk factors for failure after MUS surgery in patients with pure SUI and in those with MUI. MATERIALS AND METHODS: Two hundred twenty-eight women were categorized as having pure SUI (Group A, 163 patients) or MUI (Group B, 65 patients). Preoperative evaluations including a symptom questionnaire, physical examination, and urodynamic study were performed. Patients underwent retropubic (17.5%) or trans-obturator (82.5%) MUS surgery. RESULTS: The demographic characteristics that differed between the 2 groups were body mass index, presence of cystocele, and severity of incontinence. The success rate in Group A (95.7%) was higher than that in Group B (84.6%) (p=0.015, chi-square test). In Group A, VLPP, PdetQmax, and weight of the 1-hour pad test were identified as risk factors for failure of the operation in the univariate analysis, but only weight of the 1-hour pad test was an independent risk factor in the multivariate analysis (adjusted odds ratio [OR]=3.5; 95% confidence interval [CI]=1.204-8.895, p=0.045). In Group B, menopause without hormone replacement, AUA Symptom Index-QoL score, maximal cystometric capacity (MCC), and involuntary detrusor contraction (IDC) were the risk factors in the univariate analysis, but only MCC (adjusted OR=0.9; 95% CI=0.645-0.984, p=0.032) and IDC (adjusted OR=2.3; 95% CI=1.014-3.309, p=0.044) were independent risk factors in the multivariate analysis. CONCLUSIONS: Unlike in pure SUI, weight of the 1-hour pad test was not a significant predictor of failure of surgery in MUI. Meanwhile, MCC and IDC, which indicate the pathophysiologic status of the detrusor muscle itself, were important predictors of failure of surgery in MUI.
Animals
;
Body Mass Index
;
Contracts
;
Cystocele
;
Female
;
Humans
;
Menopause
;
Mice
;
Multivariate Analysis
;
Muscles
;
Odds Ratio
;
Physical Examination
;
Questionnaires
;
Risk Factors
;
Suburethral Slings
;
Urinary Incontinence
;
Urodynamics
5.Stability of unilateral sagittal split ramus osteotomy for correction of facial asymmetry: long-term case series and literature review.
Seong Geun LEE ; Young Hoon KANG ; June Ho BYUN ; Uk Kyu KIM ; Jong Ryoul KIM ; Bong Wook PARK
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2015;41(3):156-164
Bilateral sagittal split ramus osteotomy is considered a standard technique in mandibular orthognathic surgeries to reduce unexpected bilateral stress in the temporomandibular joints. Unilateral sagittal split ramus osteotomy (USSO) was recently introduced to correct facial asymmetry caused by asymmetric mandibular prognathism and has shown favorable outcomes. If unilateral surgery could guarantee long-term postoperative stability as well as favorable results, operation time and the incidence of postoperative complications could be reduced compared to those in bilateral surgery. This report highlights three consecutive cases with long-term follow-up in which USSO was used to correct asymmetric mandibular prognathism. Long-term postoperative changes in the condylar contour and ramus and condylar head length were analyzed using routine radiography and computed tomography. In addition, prior USSO studies were reviewed to outline clear criteria for applying this technique. In conclusion, patients showing functional-type asymmetry with predicted unilateral mandibular movement of less than 7 mm can be considered suitable candidates for USSO-based correction of asymmetric mandibular prognathism with or without maxillary arch surgeries.
Facial Asymmetry*
;
Follow-Up Studies
;
Head
;
Humans
;
Incidence
;
Orthognathic Surgery
;
Osteotomy, Sagittal Split Ramus*
;
Postoperative Complications
;
Prognathism
;
Radiography
;
Temporomandibular Joint
6.Immediate Postoperative Care in the General Thoracic Ward Is Safe for Low-risk Patients after Lobectomy for Lung Cancer.
Seong Yong PARK ; In Kyu PARK ; Yoohwa HWANG ; Chun Sung BYUN ; Mi Kyung BAE ; Chang Young LEE
The Korean Journal of Thoracic and Cardiovascular Surgery 2011;44(3):229-235
BACKGROUND: Following major lung resection, patients have routinely been monitored in the intensive care unit (ICU). Recently, however, patients are increasingly being placed in a general thoracic ward (GTW). We investigated the safety and efficacy of the GTW care after lobectomy for lung cancer. MATERIALS AND METHODS: 316 patients who had undergone lobectomy for lung cancer were reviewed. These patients were divided into two groups: 275 patients were cared for in the ICU while 41 patients were care for in the GTW immediately post-operation. After propensity score matching, postoperative complications and hospital costs were analyzed. Risk factors for early complications were analyzed with the whole cohort. RESULTS: Early complications (until the end of the first postoperative day) occurred in 11 (3.5%) patients. Late complications occurred in 42 patients (13.3%). After propensity score matching, the incidence of early complications, late complications, and mortality were not different between the two groups. The mean expense was higher in the ICU group. Risk factors for early complications were cardiac comorbidities and low expected forced expiratory volume in one second. The location of postoperative care had no influence on outcome. CONCLUSION: Immediate postoperative care after lobectomy for lung cancer in a GTW was safe and cost-effective without compromising outcomes in low-risk patients.
Comorbidity
;
Forced Expiratory Volume
;
Hospital Costs
;
Humans
;
Incidence
;
Intensive Care Units
;
Lung
;
Lung Neoplasms
;
Postoperative Care
;
Postoperative Complications
;
Propensity Score
;
Risk Factors
7.A Case Report of Multiple odontogenic keratocysts associated with basal cell nevus syndrome.
June Ho BYUN ; Seong Hee PARK ; Uc Kyu KIM ; Hae Ryoun PARK ; In Kyo CHUNG
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2000;26(3):305-309
The basal cell nevus syndrome is a well recognized entity, the major symptoms of which are basal cell nevi, multiple jaw cysts, skeletal anomalies, and ectopic calcification. The syndrome follows a hereditary pattern, which is characterized by a highly penetrant, autosomal dominant gene with multiple and variable effects. The patient often has a characteristic face, with frontal and temporoparietal bossing, which results in an increased cranial circumference. The eyes may appear widely separated, and 40 percent of patients have true ocular hypertelorism. Jaw cysts are one of the most constant features of the syndrome and are present in at least 75 percent of the patients. The cysts are odontogenic keratocysts and frequently multiple. Radiographically, the cysts in patients with basal cell nevus syndrome do not differ significantly from isolated keratocysts. The cysts in patients with this syndrome are often associated with the crowns of unerupted teeth; on radiographs they may mimic dentigerous cysts. We report a case of multiple odontogenic keratocysts associated with basal cell nevus syndrome with the literature of review.
Basal Cell Nevus Syndrome*
;
Crowns
;
Dentigerous Cyst
;
Genes, Dominant
;
Humans
;
Hypertelorism
;
Jaw Cysts
;
Nevus
;
Odontogenic Cysts*
;
Tooth, Unerupted
8.Validity assessment of self-reported smoking status in firefighters using the urine cotinine test
Han Cheol HEO ; Young Seok BYUN ; Soo Ho SOHN ; Seong Min JO ; Sung Kyu PARK ; Joon SAKONG
Annals of Occupational and Environmental Medicine 2020;32(1):e2-
BACKGROUND:
In firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters.
METHODS:
This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results.
RESULTS:
The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease.
CONCLUSIONS
In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.
9.Validity assessment of self-reported smoking status in firefighters using the urine cotinine test
Han Cheol HEO ; Young Seok BYUN ; Soo Ho SOHN ; Seong Min JO ; Sung Kyu PARK ; Joon SAKONG
Annals of Occupational and Environmental Medicine 2020;32(1):2-
Cotinine
;
Daegu
;
Firefighters
;
Fires
;
Humans
;
Male
;
Sensitivity and Specificity
;
Smoke
;
Smoking
;
Tobacco Use
10.Validity assessment of self-reported smoking status in firefighters using the urine cotinine test
Han Cheol HEO ; Young Seok BYUN ; Soo Ho SOHN ; Seong Min JO ; Sung Kyu PARK ; Joon SAKONG
Annals of Occupational and Environmental Medicine 2020;32(1):e2-
BACKGROUND:
In firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters.
METHODS:
This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results.
RESULTS:
The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease.
CONCLUSIONS
In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.