• Journal of Dental Rehabilitation and Applied Science
• /
• v.22 no.1
• /
• pp.89-100
• /
• 2006

Traditionally, goals of orthodontic treatment fall into four categories: good tooth alignment, improvement of skeletal profile and good soft tissue, and rehabilitation of the normal function. Electromyography (EMG) has proven as useful tool in evaluating masticatory function among the maxillomandibular relationship and could be useful in accompanying orthodontic treatment objectives. But in pursuit of clinical application, it is necceassry to systemize clinical guideline for diagnosis by EMG records in evaluating the effects of orthodontic, orthopedic, or surgical treatment. This study present 3 orthodontic cases, which treatment results, ie neuromuscular balances of masticatory muscle, could be moitered by EMG procedure.

• Proceedings of the KIEE Conference
• /
• 1998.07b
• /
• pp.611-613
• /
• 1998

A structure of musculotendon model with a fatigue profile is investigated. The Hill-type musculotendon model can predicts the decline in muscle force for a given fatigue profile. It consists of nonlinear activation and contraction dynamics based on the physiological concepts. It is normalized for generalization to deal with the various muscles. Muscle force generated by continuous tetanic electrical monophasic pulsewidth modulation stimulation is decreased in time. A fatigue profile is expressed by a function of intramuscular acidification and applied to the relationship between muscle force and shortening velocity in contraction dynamics. The results of computer simulation are well matched with data in a literature which are isometrically performed for knee extension muscles. Also change in optimal fiber length has an effect only on muscle time, constant not on the steady-state tetanic force.

• The korean journal of orthodontics
• /
• v.32 no.4 s.93
• /
• pp.265-274
• /
• 2002

Among many maturation indicators of growing patients, menarche and skeletal maturity are useful to assess growth and development, and the changes of the first and third finger are relatively important in hand-wrist X-rays. The objective of this study was to evaluate the relationship between menarche and the changes of the phalanx of the first and third finger and compare skeletal maturation among different malocclusion types. The sample used in this study was 29 Class 1,27 Class II and 27 Class III females whose hand-wrist X-rays had been taken with 6 month interval before the appearance of ulnar sesamoid ossification till the phalanges of the fingers were almost fused. The results were as follows. 1. There was no skeletal maturity difference among malocclusion types. 2. There was no difference in the mean chronologic age of menarche among different malocclusion types and that was $12.30\pm0.98$ years. 3. The ulnar sesamoid was observed at $10.35\pm1.01$ years, and on distal phalanx of the first finger, epiphyseal capping appeared at $11.26\pm1.04$ years and fusion at $13.12\pm1.06$ years. The epiphyseal capping on middle phalanx of the third finger was observed at $11.57\pm1.02$ years and fusion at $13.72\pm1.04$ years. 4. The timing of menarche occurred around the same time as the fusion process of distal phalanx of the first finger(p<0.001, r=0.82) and the initiation of fusion of middle phalanx of the third finger(p<0.001, r=0.78). Therefore, we can give the aid when we evaluate the growth and development of growing females seeing the changes at phalanx of the first and third finger.

• The korean journal of orthodontics
• /
• v.30 no.1 s.78
• /
• pp.1-7
• /
• 2000

It is important that the orthodontist accurately assess the degree to which facial asymmetry contributes to a given malocclusion before treatment planning. P-A, submentovertex and verticosubmental view have been used in the assessment of facial asymmetry. Among them, submentovertex view is rarely used because it has low reproducibility and is short of normal data and proper analysis method. The purpose of this study was to develop a submentovertex cephalomentrics and obtain normal data in Korean adults. The subjects consisted of 40 normal adults (male : 22, female 18) without the experience of orthodontic treatment. We find the 2 angular and 9 linear measurements. Though submentovertex cephalomentrics has the limitation in comparing the absolute length between right and left, it is useful to examine the relationship of skeletal and dental midline, the shape and location of condyle head and the shape of mandibular body in submentovertex view Therefore, if we understand the limitation of submentovertex cephalomentrics and use lateral , P-A and submentovertex cephalomentrics together, we will measure the location and amount of skeletal disharmony more exactly.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.6
• /
• pp.994-1001
• /
• 2007

Changes in shear force value, transverse sections, myofibrils and intramuscular connective tissue of bovine skeletal muscle exposed to the combination of high-pressure up to 400 MPa and heat (30 and $60^{\circ}C$) were studied. The shear force value decreased by pressure-heat treatment up to 200 MPa at 30 and $60^{\circ}C$, and then slightly increased over 200 MPa at $30^{\circ}C$. Shear force values of treated muscles were lower than those of untreated ones. Gaps between muscle fibers in the untreated muscle were a little clear, and then they became very clear in the treated muscles up to 200 MPa at 30 and $60^{\circ}C$. However, the gaps reduced significantly over 200 MPa at $30^{\circ}C$. The remarkable rupture of I-band and loss of M-line materials progressed in the myofibrils with increasing pressure applied. However, degradation and loss of the Z-line in myofibrils observed in the muscle treated at $60^{\circ}C$ was not apparent in the muscle treated at $30^{\circ}C$. The length of the sarcomere initially contracted by pressure-heat treatment of 100 MPa at $30^{\circ}C$ seemed to have recovered with increase of the pressure up to 400 MPa. In the muscle treated at $60^{\circ}C$, the length of sarcomere gradually decreased with increase of the pressure up to 400 MPa. In the treated muscles, changes in the honeycomb-like structure of endomysium were observed and accelerated with increase of the pressure. A wavy appearance clearly observed at the inside surface of endomysium in the untreated muscles gradually decreased in the treated muscles with increase of the pressure. Tearing of the membrane was observed in the muscles treated over 150 MPa at $30^{\circ}C$, as observed in the sample pressurized at 100 MPa at $60^{\circ}C$. The roughening, disruption and fraying of the membrane were observed over 200 MPa at $60^{\circ}C$. From the results obtained, the combination of high-pressure and heat treatments seems to be effective to tenderize tough meat. The shear force value may have some relationship with deformation of intramuscular connective tissue and myofibrils.

• Imaging Science in Dentistry
• /
• v.44 no.1
• /
• pp.61-65
• /
• 2014

Purpose: This study was performed to evaluate the position of impacted mandibular third molars in different skeletal facial types among a group of Iranian patients. Materials and Methods: A total of 400 mandibular third molars in 200 subjects with different types of facial growth were radiographically investigated for their positions according to their types of facial growth on the basis of the ${\beta}$ angle. The subjects were divided into three groups (class I, II, and III) according to ANB angle, representing the anteroposterior relationship of the maxilla to the mandible. Meanwhile, the subjects were also divided into three groups (long, normal, and short face) according to the angle between the stella-nasion and mandibular plane (SNGoGn angle). ANOVA was used for statistical analysis. Results: The mean ${\beta}$ angle showed no significant difference among class I, II, and III malocclusions (df=2, F=0.669, p=0.513). The same results were also found in short, normal, and long faces (df=1.842, F=2, p=0.160). The mesioangular position was the most frequent one in almost all of the facial growth patterns. Distoangular and horizontal positions of impaction were not found in the subjects with class III and normal faces. In the long facial growth pattern, the frequency of vertical and distoangular positions were not different. Conclusion: In almost all of the skeletal facial types, the mesioangular impaction of the mandibular third molar was the most prevalent position, followed by the horizontal position. In addition, ${\beta}$ angle showed no significant difference in different types of facial growth.

• 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.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.39 no.3
• /
• pp.133-145
• /
• 2023

Class III malocclusion with mandibular protrusion can be divided into skeletal and pseudo malocclusion due to tooth displacement. For skeletal malocclusion, favorable treatment results can be obtained by establishing an appropriate vertical and horizontal intermaxillary relationship in order to secure a restoration space and obtain aesthetic and functional results. In this case, complete mouth rehabilitation was performed using an implant and a fixed prosthesis in a patient with mandibular protrusion and anterior teeth wear and reduced occlusal vertical dimension. After cast analysis and digital diagnosis, a provisional restoration with increased vertical dimension was fabricated to secure posterior support and evaluate stable centric occlusion. With the definitive prosthesis reflecting the provisional restoration, favorable function and aesthetics were obtained.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.38 no.2
• /
• pp.119-128
• /
• 2011

In the process of assessing the children with anterior crossbite in early mixed dentition, it has frequently been detected that the stronger the skeletal pattern of the malocclusion is, the more markedly delayed the development and eruption of maxillary teeth are. If the anteroposterior characteristics of craniofacial skeleton has any relationship with dental maturation, the evaluation of dental development and eruption was thought to be able to contribute to early diagnosis of crossbite in children. This study was performed for the purpose of elucidating the relationship between dental maturation of maxillary teeth and some cephalometric values in children with anterior crossbite of maxillary undergrowth type in early mixed dentition. Among the children in Hellman dental age IIA and IIC who attended the Pediatric Dental Clinic of Pusan National University Hospital with orthodontic problems, cases with Class III malocclusion were classified and 50 cases of maxillary undergrowth type and type with normal maxilla respectively were randomly selected and studied as subjects. From their lateral cephalographs and panoramic radiographs, their anteroposterior skeletal features, the dental maturity and eruption rate were obtained of each group and data were analyzed to yield the results as follows: 1. Comparing the maturity of maxillary teeth of both groups, only the first molars of maxillary undergrowth group showed significantly slower development and eruption (p<0.05). 2. There was high correlation between maturation of maxillary 1st molar and chronological age(p<0.05). 3. Among the parameters of anteroposterior relationship of skeletal pattern in maxilla and mandible. Wits was revealed as a useful index to predict both the calcification and eruption rate of the 1st molars whereas SNA was to eruption rate(p<0.05).

• Journal of agricultural medicine and community health
• /
• v.26 no.2
• /
• pp.193-203
• /
• 2001

The purpose of this study was to identify the relationship between depression and physical health of the elderly and to provide fundamental data for programs which improve the health of this population. The subjects were 168 elderly people(55 years and older) who resided at home in Taegu. They were surveyed by interview using a closed- ended questionnaire. The survey was done from September 16 to October 16 in 2000. The instruments used in this study were general characteristics, Short form Geriatric Depression Scale(SGDS), Barthel Index, Muscular skeletal symptoms scale, Northern Illinois University's Health Self Rating Scale. The data were analyzed by using descriptive statistics, t-test, ANOVA, Pearson Correlation Coefficient, multiple regression with SPSS PC 10.0 version for Windows. The findings were as follows: 1. As compared 65-74 years elderly group, 75-84 years group was significantly higher score for depression(F=3.17, p=.026). As compared elderly group who has own spouse, the group who has no own spouse was significantly higher score for depression(t=- 2.44, p=.016). 2. The aged who have more limitation of Activities of Daily Living(ADL)(t=3.93, p=.000), pain of muscular skeletal symptoms(F=5.33, p=.002) and poor perceived health state(F=17.04, p=.000) showed the higher severity of depression than the aged who have not. 3. ADL correlated negatively with depression(r=- .293, p=.000), pain of muscular skeletal symptoms correlated positively(r=.251, p=.001), perceived health status correlated negatively(r=-.522, p=.000). 4. The combination of perceived health status and ADL explained 29.1% of the varience of depression. On the basis of the above findings the following recommendations are made; 1. Developing health programs is needed considering ADL, pain of muscular skeletal symptoms, perceived health status, demographic variables (age, spouse status) which have an significant effects on depression of the elderly. 2. In the following study, the use of the various scale is needed which reflects physical status of the elderly in home.