• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.399-417
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• 2008

The aim of this study was to investigate the relationships between bite force, masseter muscle and craniofacial morphology. 141 individuals were included. Bite forces were measured with a bite force transducer(SKT 2004). The facial morphology of the samples was evaluated on the Lateral and PA cephalometric radiographs(Asahi CX-90 SP). Ultrasonographic images were obtained for 36 individuals(Logiq 500). General status of the subjects were also measured for investigating possible relationships. Their relationships were analyzed by means of t-test, Pearson's correlation coefficients and simple regression analysis. In conclusion, bite force of molar was significantly correlated with craniofacial morphology for males and females, but not to masseter muscles. The masseter muscle for males had a significant correlation with craniofacial morphology. The unexpected negative correlations between size of masseter muscle and maxillary width was revealed for males. One possible way to arrive at a plausible explanation for the correlation between masster muscle, bite force and craniofacial morphology of males were the deep layer of masseter muscle had a great influence on males and the superficial layer of masseter muscle had a great influence on females.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.119-127
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• 1997

The configuration of mandibular symphysis is likely to be dependent upon the genetic predeterminants and/or compensatory adjustments onto functional demands. The interrelation of morphological distinctives of symphysis in conjunction to the craniofacial skeleton had been scarcely anecdotal, therefore, the objective was to determine the correlation of morphological modifications between the mandibular symphysis and craniofacial complex. Lateral cephalometric headfilms of 212 subjects were employed for the conventional measurements. The proportion of chin height against chin depth length was referred as chin ratio, then, Low Symphysis (IS) and High Symphysis (HS) groups were turned out by means of the chin ratio. These samples yielded 35 in LS and 35 in HS groups. The data per capita were statistically analyzed and the following results were drawn ; 1. Overall characteristics of the craniofacial skeleton in HS group manifested hyperdivergence and LS group showed hypodivergence. 2. Gonial angle increased as chin ratio increased and was highly correlated to the chin ratio. 3. The chin ratio presented high correlation to the vertical face height, especially in terms of the chin height to anterior face height and the chin depth to posterior face height. 4. The morphological configuration of chin was hardly correlated with hyoid bone position.

• Journal of Yeungnam Medical Science
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• v.18 no.1
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• pp.112-122
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• 2001

Background: Cleft lip and palate deformity have unknown patterns of maxillofacial growth and development. The maxillofacial growth can be affected either by congenital or environmental factors such as infection and trauma. Surgical repair of cleft lip and palate may interfere the subsequent growth and development of maxillofacial region. The purpose of this study is to evaluate the characteristics of maxillofacial growth patterns in adult cleft lip and palate patients. Materials and Methods: The material for this study consisted of 17 adult male patients with cleft lip and palate. Cephalometric tracing and measurements were done by one investigator. The relationship between 17 cleft lip and palate patients and Korean norms were evaluated statistically. Results: There were statistically differences in Na. perpendicular to point A, SNA angle, effective maxillary length, maxillofacial differencial. Wit's appraisal and upper incisor to point A(p < 0.01). Pogonion to Na. perpendicular also statistically differed(p < 0.05). Other measurements didn't statistically differ. Conclusion: It was evident that in adult cleft lip and palate patients, maxilla was retruded and short. Careful cleft lip and palate repair and treatment are recommended for facilitating normal growth of maxilla.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.159-172
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• 2001

Three dimensional analysis of malocclusion and craniofacial deformation is essential for the successful orthodontic treatment. But the orthodontists are not familiar with diagnosis and treatment plane based on lateral cephalometric analysis. Since orthodontists do not posses a sufficient knowledge in standard value of posteroanterior cephalometric anaysis and of clinical importance for transverse jaw growth. In this study male(n=130) and female(n=171) aged from 6 to 16 and diagnosed as Class I malocclusion were selected to analysis width of cranium, maxilla and mandible on the posteroanterior cephalogram. The changes as a function of chronologic age and cervical vertebrae maturity index(CVXI) were examined. The Proper regression model was selected by sex with polynominal regression models and method of variable selection. Mean of each measurements and 70% confidence interval of individual measurement according to age was assesed and a graphs were made. Results are as follows :1. All the measurements for the width are gradually incresed as increase in chronologic age and CVMI. From the total amount of change between age 6 and 16, there is a tendency that mandibular width is broader than maxillary width and the width of male is broader than female. 2. There is no statistically significant sexual difference in Mx-Mn difference, Mx-Mn width differential, Mx/Mn ratio according to age and CVMI. 3. Mean of each measurement and 70% confidence interval of individual measurement according to age and sex were assessed and graphs were made for maxillary width, mandibular width, Mx-Mn difference, Mx/Mn ratio. 4. The width of maxilla and mandible in Korean children are broader than Western children during growth period.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.855-864
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• 1998

The purposes of this study were to evaluate the cephalometric characteristics of Korean female patients with Class II division 2 malocclusion and to compare Korean females with Caucasian females who had same type of malocclusion. All of the samples had Class II division 2 malocclusion with deep overbite (more than 4mm) and full permanent dentition. These samples were divided into two groups according to the races: Group 1(N=16; Korean females; average age=18Y 2M) and Group 2 (N:20; Caucasian females; average age=14Y 2M). The pretreatment lateral cephalograms were measured, analyzed and compared by using 38 variables and independent t-test. And the results were as follows: 1. Although there were no differences in Overbite, SN to mandibular plane angle, Palatomandibular plane angle, and FMA between Group 1 and 2, the other vertical relation variables of maxilla and mandible (SN to palatal plane angle, SN to occlusal plane angle, ODI) of Group 1 showed more clockwise rotation tendency of occlusal plane and less hypodivergency tendency than those of Group 2. 2. There were no differences in mandibular body length and ramus height between Group 1 and 2 except small upper genial angle of Group 1. There was less counterclockwise rotation tendency of mandible in Group 1. 3. There were no statistical significant differences in UAFH/LAFH and PFH/AFH between Group 1 and 2. 4. Although there were no differences of overjet and anteroposterior position of mandible between Group 1 and 2, the position of maxilla of Group 1 was more retropositioned than that of Group 2. 5. Except the more protrusion of lower incisor to A-Pog of Group 1, there were no differences of inclination and distance of upper and lower incisors to basal plane between Group 1 and 2. 6. The distance from upper- first molar to palatal plane showed no difference between Group 1 and 2. But the distance from lower first molar to mandibular plane of Group 1 was greater than that of Group 2. So it may be partially related to the clockwise rotation of occlusal plane and the less counterclockwise rotation tendency of mandible of Group 1. 7. Group 1 had more protrusive upper and lower lips than Group 2.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.343-351
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• 1998

The purpose of this study was to investigate the pretreatment and posttreatment dentofacial characteristics of non-extraction patients with Class I malocclusion. And to compare this result with matched non-orthodontic normal occlusion and Class I premolar extraction patients. Such comparison might help identify morphologic characteristics of the non-extraction patients. Initial and final cephalometric evaluation were compared in a sample of 22 patients with Class I malocclusions treated in non-extraction manner with edgewise appliance and MEAW The mean age of the total population was 14 years 9 months and the average treatment time was 2 years 8 months. 32 landmarks were located and digitized on each cephalogram. From these landmarks, 24 linear and angular dimension were obtained. Student's t-test were used to compare the pretreatment - posttreatment results, Nonextraction - Normal groups, and nonextraction Extraction groups. Significance was predetermined at $p{\leq}0.05$. The results were as follows. 1. Before treatment, the mean value of the $ODI\;was\;69.9^{\circ},\;APDI\;was\;82.1^{\circ},\;CF\;was\;152^{\circ},\;EI\;was\;152^{\circ}$ in the non-extraction groups. 2. The skeletal pattern of the non-extraction groups were similar with non-orthodontic normal groupsr, but the non-extraction groups had larger interincisal angle. 3. Comparison between groups treated with and without extraction indicated at pretreatment, the extraction groups had more protrusive lips, smaller interincisal angle, and EI. 4. After treatment, there was no significant changes in the skeletal pattern of the non-extraction groups, but uprighting of the maxillary and mandibular first molar and decrease of the interincisal angle were seen.

• The korean journal of orthodontics
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• v.19 no.1 s.27
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• pp.187-200
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• 1989

The purpose of this study was to find out the craniofacial skeletal characteristics and to establish standards in facial patterns of Korean adolescences with normal occlusion. The subjects consisted of 54 males and 71 females ranging in age from 12 to 16 years. To classify facial patrons, number the clinical deviations from the normal five key measurements: the facial axis, facial angle, mandibular plane angle, lower face height, mandibular arc, are added and averaged with the proper sign to divide subjects into three groups ; brachyfacial, mesofacial dolichofacial groups. For the comparison of each group, a total of 43 morphologic variables were employed and the data were analyzed by statistical methods. The findings of this study can be summerized as follows; 1. The mesofacial group was $54.4\%$, the brachyfacial group was $29.6\%$ and the dolichofacial group was $16.0\%$ in this subjects. 2. There were no significant differences in size and shape of cranial base among each groups. 3. The brachyfacial group manifested the forward positioned maxilla and mandible to anterior cranial base, smaller cant of the mandibular plane, square shaped mandible, and prominent symphysis as compared with dolichofacial group. 4. There were no significant differences in the cant of the maxilla to the anterior cranial base among each groups. 5. Ramal height and madibular body length of brachyfacial group were larger than those of dolichofacial group. 6. Brachyfacial group indicated the smallest degree in divergency of maxilla and mandible while dolichofacial group showed the largest degree.

• The korean journal of orthodontics
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• v.24 no.1 s.44
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• pp.199-220
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• 1994

This study was conducted to determine the electromyographic features in the perioral muscles of class II division 1 malocclusion with incompetent lips, and to grope the correlation between its activities and craniofacial morphology. Tn this study, 14 subjects with class II division 1 malocclusion with incompetent lips(mean age of 20.5 years) and 20 subjects with normal occlusion(mean age of 23.9 years) were investigated. Electromyographic data were recorded from orbicularis oris, mentalis, buccinator and suprahyoid muscles durig rest lip posture, lip position at sealing, maximum sealing, maximal blowing, maximal biting, sipping milk, sipping and swallowing milk, chewing gum, masticating almond, swallowing almond and phonation utilizing the Medelec MS-25 electromyographic apparatus. Lateral cephalometric radiographs were taken with the mandible in intercuspal position on all subjects. All data were recorded statistically processed. The findings of this study can be summerized as follows : 1. In class II division 1 malocclusion with incompetent lips, the overall augmentations of perioral muscle activities during various functionel movements set for lip sealing were manifested and particular swelling in mentalis activity at rest was detected. 2. On the other hand remarkable diminution of upper lip acitivities at lip sealing movements was drawn. 3. In Class II division 1 malocclusion with incompetent lips, negative correlations existed between the diversity of upper lip activities and upper incisor position and overjet as well in contrast to positive correlations in the lower lip. 4. It was suggested that the abnormal function of lower lip and mentalis muscle contributed somewhat the revelation of the characteristics of Class II division 1 malocclusion.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.6
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• pp.606-612
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• 2000

This study was performed to investigate the average anthropometric value of normal Korean men and women and to compare the preceding literatures. Additionally, average Korean profilogram was made to serve as a template for diagnosis of facial form. Eighty five Korean subjects(41 men, 44 women) aged between 21 to 26 were selected by members of the author's department on the basis of intact dentition and Class I occlusion without facial asymmetry. Frontal and lateral photographs were taken under standardized condition with digital camera. The image was magnified and adjusted according to the FH plane of cephalometric radiographs and digitized using personal computer. To compare the Western beauty, 25 esthetically pleasing female was selected to measure various angle and distance of the face. 1. It was possible to calculate the mean coordinate value of Korean normal samples which enables the direct visualization and comparison with the use of template. The method in this study was easy to applicate under the Microsoft $Windows^{(R)}$ bases. 2. Maxillary vertical hypoplasia, upper and lower lip protrusion was characteristics of Korean norms and relatively narrow alar base distance, less conspicuous nasal projection was observed. As the vermilion exposure and upper lip length was more than western norm, chin looks shorter than western. To compare the Korean and Western esthetically pleasing profile, facial convexity and nose was less conspicuous in Korean women.

• Journal of Korean Dental Science
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• v.13 no.1
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• pp.11-20
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• 2020

Purpose: This study sought to identify differences in hard and soft tissue chin profile changes in skeletal Class III patients after bimaxillary surgery, with or without advancement genioplasty. Materials and Methods: The retrospective study was conducted based on cephalometric analysis of skeletal and soft tissue variables. Lateral cephalograms taken at 3 different time points were utilized: pre-operation (T0), immediately post-operation (T1), and at least 6 months (11.0±2.6 months) post-operation (T2). The 2 groups were matched for sample size (n=20 each). Data were analyzed using independent t-tests with Bonferroni correction. Result: Group N (bimaxillary surgery alone) and Group G (bimaxillary surgery with an advancement genioplasty by horizontal sliding osteotomy) did not differ significantly in terms of demographic characteristics. The soft tissue chin thickness of Group G increased more after surgery, followed by a greater decrease during the postoperative period, and was eventually not significantly different from Group N at T2. On the other hand, the mentolabial sulcus depth of Group G (5.5±1.3 mm) was significantly greater than that of Group N (4.4±0.9 mm) (P=0.006) at T2. Conclusion: Although Group G showed a statistically significantly greater decrease in soft tissue chin thickness during the postoperative period, there were no significant intergroup differences in the chin profile for at least 6 months after the surgery, except for the mentolabial sulcus depth, which was greater in Group G than in Group N.