• The korean journal of orthodontics
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• v.17 no.2
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• pp.215-221
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• 1987

This study was designed to investigate the growth amount and rate of mandible by the measurements of mandibular lateral surface and the relationship of peak growth increments between mandible and body height The sample consisted of twenty-five boys and fifteen girls between the ages of 6 and 13 The surface of mandible was measured from digitized roentgenocephalometric analysis (A 27 point mandibular model) The findings of this study can be summarized as follows 1 No significant difference was found between mandibular lateral surfaces of the both sexes at the ages studied. 2 The mean growth amount of mandibular lateral surface from 6 to 13 years of ages was $9\;09cm^2$ in boys and $8\;29cm^2$ in girls, and the mean growth rate was 46 07% in boys and 42 57% in girls 3 The prepubertal peak growth increment in mandible was found between the ages of 11-12 in girls and 12-13 in boys 4 The prepubertal peak growth increments of mandible occured one year later that of body height in boys and girls.

• The korean journal of orthodontics
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• v.22 no.3 s.38
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• pp.603-615
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• 1992

This study was undertaken to investigate the interrelationship between the growth change of mandible and the developmental age of growing girls in the longitudinal data from 7 years to 15 years. The data were obtained from maturation stage of cervical vertebrae through the serial lateral cephalogram, height increment records which was taken at one year interval, menarche date through interview. On the basis of findings of this study, the following conclusions were obtained. 1. In general the growth of mandible (Ar-Pog, Ar-Go, Go-Pog) showed two peaks of growth velocity. 2. The maximum growth of mandible (Ar-Pog, Ar-Go, Go-Pog) almost appeared between stage 3 and stage 4 in maturation of cervical vertebrae. 3. It showed the tendency that the maximum increment of height appeared faster than that of mandible (Ar-Pog, Ar-Go, Pog-Go). 4. The maximum growth of height almost appeared between stage 2 and stage 3 in maturation of cervical vertebrae. 5. It showed the tendency that the menarche appeared later than the maximum growth of mandible (Ar-Pog, Ar-Go, Pog-Go). 6. The menarche almost appeared at stage 4, stage 5 in maturation of cervical vertebrae.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.126-132
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• 1999

This article describes the use of an activator with anterior high pull headgear to treat a skeletal Class II malocclusion in children in the mixed-dentition phase. A combination of headgear-activator appliance can inhibit forward and downward growth of the maxillary complex while stimulating mandibular growth. The correction of Class II malocclusion can be achieved by careful case selection of a motivated patient with a favorable growth pattern. The patients who have skeletal Class II malocclusions were treated by means of activator with anterior high pull headgear and the following results were observed; 1. Forward and downward growth of the maxillary complex were inhibited 2. Mandibular growth was stimulated and counterclockwise rotation of the mandible was observed. 3. Large overjet and deep overbite were corrected.

• The korean journal of orthodontics
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• v.19 no.1 s.27
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• pp.77-93
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• 1989

The purpose of the present study were to disclose whether the depth of the mandibular antegonial notch can be used as an indicator of mandibular growth potential. The patients composed of 76 samples and were classified following 3 groups, based on the depth of mandibular antegonial notch : Deep notch group (more than 3mm), Neutral notch group (1-3mm), Shallow notch group (less than 1mm). For each case, the first lateral cephalograms were taken prior to the start of treatment and the second films 3-4 years after. The results were as follows; 1. Deep notch group had a shorter corpus, less ramus height and greater genial angle than did Shallow notch group. 2. Deep notch group had a more retrusive mandibular position than Shallow notch group. 3. Deep notch group had longer total anterior facial height and longer anterior lower facial height group. 4. Deep notch group grow vertical clockwise growth pattern, while Shallow notch group grow horizontal counterclockwise growth pattern. 5. Deep notch group had less mandibular growth than Shallow notch group during observation period.

• The korean journal of orthodontics
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• v.11 no.1
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• pp.25-30
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• 1981

Fifteen young pigs were used in this study. The animals were divided into three groups 1. Group for removal of the temporal muscle, 2. Group for removal of the masseter muscle, 3, Group for removal of masseter and internal pterygoid muscles. The animals were anesthetized with $3.5\%$ chloral hydrate intraperitoneally. In the right side the head was shaved. The masticatory muscle was removed. The animals were sacrificed four months later. The head was separated from trunk and cleaned by boiling in a solution of potassium hydroxide. The results were as follows; 1. In the group for removal of the temporal muscle, the Coronoid process of the mandible was resorbed. 2. In the group for removal of the masseter muscle, there was produced asymmetrical growth of the mandible, attrition of the molar teeth in the control side, and resorption of the mandibular angle. 3. In the group for removal of the Masseter and Internal muscles, the changes were more severe than that of the group for removal of the masseter muscle. The mandibular angle was completely absent. 4. The growth of the bone seems definitely related to the presence of the muscular tissue actively pulling upon it.

• The korean journal of orthodontics
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• v.16 no.1
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• pp.119-131
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• 1986

The purpose of the study is to note the effects of the resection of the lateral pterygoid muscle on the mandibular growth in the growing rats. Twenty four female Wistar rats were used in the experiment. They were divided into three groups: group 1 ; bilateral sham operation group 2 ; bilateral resenction of the lateral pterygoid muscle group 3 ; unilateral resection of the lateral pterygoid muscle (The right lateral pterygoid muscle was resected and the left one was sham-operated.) Groups 1&2 were sacrificed eight weeks lateral and group 3, four weeks later. All specimens were measured with calipers, and stained with hematoxylin and eosin. Groups 1 & 2 were compared with each other. In group 3, the right side was compared with the left. The results were as follows: 1. In the growing rats, the resection of the lateral pterygoid muscle was followed by a decrease of the mandibular growth. After eight weeks, the condyle-mental foramen distance, the angular process-mental foramen distance, the size of the condylar head, the supradentale-first molar distance, and the diameter of the symphysis were significantly smaller than the control. 2. Resection of the lateral pterygoid muscle resulted in decrease of the thickness of the cartilage layer and the prechondroblastic-chondroblastic layer after four weeks. 3. After eight weeks, group 1 and group 2 were not different significantly in the histologic sections. 4. The condylar cartilage was stabilized eight weeks after the experiment.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.3
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• pp.246-250
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• 2018

Ameloblastoma is a benign neoplasm originating from odontogenic epithelium. It is the most common neoplasm in the jaws and is characterized by aggressive behavior and local invasion. Unicystic ameloblastoma (UA) has a unilocular feature in radiologic examination and a cystic feature histologically. Decompression and marsupialization are conservative method of treatment of large UA. The purpose of decompression and marsupialization are size reduction of the mass, which makes it easy to handle at total enucleation with protection of nerve damage and facial deformity. Here we report successful conservative treatment of extensive UA using decompression and marsupialization with a review of literatures.

• The korean journal of orthodontics
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• v.12 no.2
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• pp.117-126
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• 1982

The author evaluated the effect of chin cap for the growing patient with cross-bite. The date were obtained from superimposition of pre and post-treatment lateral cephalograms. The results might be as follows; 1. increase ANB angle, Y-axis angle, SN-MP angle. 2. made anterior facial height more greater than posterior facial height. 3. as a results, rotate mandible backward.

• The korean journal of orthodontics
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• v.15 no.2
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• pp.175-195
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• 1985

Vertical and horizontal growth occur in the craniofacial complex which ensues continuous changes in facial morphology, until the end of active growth period. Longitudinal study for individual is essential, in the research on growth and development, however, the difficulties in obtaining long term subjects in Korea, the research has been limited. The author analyzed the cephalometric roentgenogrems of 43 boys and 47 girls taken from the ages 6 to 10. The subjects were divided into 3 groups according to SN-MP angle and 2 groups according to gonial angle. In this longitudinal study, 21 variables were measure 4. The obtained results were as follows: 1. SN-MP angle and genial angle had no significant changes in each group with age. 2. With age, facial convexity of hard tissue decreased in all groups, facial angle of hard tissue increased in low SN-MP angle group, but facial convexity of soft tissue had no significant changes in all groups with age. 3. In comparison of high SN-MP angle group and low SN-MP angle group, the former had greater facial convexity and smaller facial angle than the latter. 4. SN-MP angle and the ratio of posterior dental height to anterior dental height had reverse correlation in all groups. 5. High genial angle group revealed larger SN-MP angle, anterior dental height facial convexity, but smaller mandibular length, and the ratio of posterior dental height to anterior dental height compared with low genial angle group.

• The Journal of the Korean dental association
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• v.56 no.2
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• pp.103-112
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• 2018

The treatment of skeletal Class II growing patient is to move the mandible into the Class I molar positon via facilitating mandibular growth. The functional appliances are to be designed to exert three major functions such as palatal expansion, forward growth of mandible and increase of the posterior vertical dimension. One of the devices that can achieve both the palatal expansion and the eruption of the mandibular molar is the Twin-Block introduced by Clark in 1982. In this part, we present the treatment method with Twin-Block functional appliance for the correction of skeletal Class II growing patient.