1.Experimental study on the effect of heat treatment on the orthodontic wires.
Myung Seok LEE ; Byung Wha SOHN
Korean Journal of Orthodontics 1992;22(3):591-601
No abstract available.
Hot Temperature*
;
Orthodontic Wires*
2.A roentgenocephalometric study on soft tissue profile changes in pre-post treatment of Angle's Class II division I malocclusion.
Korean Journal of Orthodontics 1983;13(2):193-198
No abstract available.
Malocclusion*
3.A roentgenocephalometric study on soft tissue profile changes in pre-post treatment of Angle's Class III malocculusion.
Korean Journal of Orthodontics 1983;13(2):177-183
No abstract available.
4.Radiologic Evaluation About Urinary Tract Infection In Children.
Soon Wha KIM ; Byung Rai CHO ; Don Hee AHN ; Keun Chan SOHN ; Chong Hyun YOON
Journal of the Korean Pediatric Society 1989;32(6):797-803
No abstract available.
Child*
;
Humans
;
Urinary Tract Infections*
;
Urinary Tract*
5.A longitudinal study on the interrelationship between the growth change of the mandible and developmental age of growing girls.
Young Joon KIM ; Byung Wha SOHN
Korean Journal of Orthodontics 1992;22(3):603-615
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.
Cervical Vertebrae
;
Female*
;
Humans
;
Longitudinal Studies*
;
Mandible*
;
Menarche
6.A study of biting force in long face and normal face adults.
Tai Jyung YOO ; Byung Wha SOHN
Korean Journal of Orthodontics 1990;20(3):591-602
Until now it has not surely been pointed out about the relation between the biting force and the facial types in scientific view. But it's correlation was assumed by several scientists: recently some literatures reported about the maximum biting force and facial types, but there's only a little articles about the relation between the biting force(biting force contain maximum biting force, chewing force and swallowing force) and facial type. So this study was, firstly, performed to establish the relation of the normal face and long face versus biting force. 2ndly it was performed to establish the relation between the difference in mouth opening degrees versus biting force. 3rdly it was performed to establish the relation between male and female versus biting force. Biting force was measured from 56 adults (normal 26, long 30) whose samples was selected from Yonsei university students and Hospital patients. Sample was divided into 2groups (normal and long) by lateral cephalogram. The results of this study was obtained as follows. 1. Maximum biting force and chewing force in long face was smaller than normal face. 2. When the thickness of transducer was changed from 6mm to 9mm, maximum biting force and chewing force was larger than before. 3. In case of comparing with male and female, male was larger than female in maximum biting force and chewing force.
Adult*
;
Deglutition
;
Female
;
Humans
;
Male
;
Mastication
;
Mouth
;
Transducers
7.A study of the crown angulation in normal occlusion.
Jung Jin YOON ; Byung Wha SOHN
Korean Journal of Orthodontics 1986;16(2):123-133
The purpose of this study was to collect the information of the straight-wire appliance and to determine the amount of second-order bends in clinical orthodontics. The author analysed the study model of 50 individuals with normal occlusion and results were obtained as follows 1. The crown angulation was 4 degree in upper central incisor, 7 degree in upper lateral incisor, and 0 degree in lower central incisor and lateral incisor. 2. The crown angulation was 8 degree in upper cuspid and 2 degree in lower cuspid. 3. The crown angulations were 4 degree in upper first bicuspid, upper second bicuspid and lower second bicuspid and 1 degree m lower first bicuspid. 4. The crown angulation was 3 degree in upper first molar, 0 degree in upper second molar, 5 degree in lower first molar and 8 degree in lower second molar. 5. The crown angulations in lower arch were progressively increased from first premolar to second molar. 6. In upper arch, as the crown angulation of one tooth was increased, those of adjacent teeth were increased, too. 7. In the case of lower arch, the crown angulation of cuspid was increased as that of lateral incisor was increased, the crown angulation of second premolar was increased as that of first premolar was increased, and similarity the crown angulation of second molar was increased as that of first molar was increased.
Bicuspid
;
Crowns*
;
Cuspid
;
Decompression Sickness
;
Incisor
;
Molar
;
Orthodontics
;
Tooth
8.A statistical study of dental crowding with dental cast analysis.
Byung Wha SOHN ; Chung Ju HWANG
Korean Journal of Orthodontics 1991;21(2):273-285
Crowded group is composed of 60 subjects who visited Yonsei University for orthodontic treatment and has no history of orthodontic treatment. Noncrowded group is composed of 26 subjects who has no crowding, considered to have a normal occlusion and no history of orthodontic treatment. Currently available and approved analytic method was used. Interrelationship between tooth size and arch size, and it's correlation on tooth crowding was studied and the following results were obtained. 1. In comparison of sum of mesiodistal width, of crown size of teeth was greater in noncrowded group than that of crowded group on both arch. (p<0.01). 2. In comparison of arch lengths, the values measured from arch length 2 showed greater in non crowded group (p<0.01). Also in crowded group, arch length 1 showed greater value than arch length 2 on both arch (p<0.01). 3. In comparison of arch widths, upper interlateral (p<0.01) and upper intercanine width (p<0.05) showed greater value in noncrowded group on upper arch and intermolar width showed greater value in noncrowded group on both upper and lower arches (p<0.05). 4. In comparison of arch perimeters, arch perimeter 2 was greater value in noncrowded group on both upper and lower arches (p<0.01). 5. Dentoalveolar disproportion was greater in noncrowded group on both upper and lower arches (p<0.01). 6. In lower incisors MD/FL ratio, the central and lateral incisors were greater in crowded group, but statistial significance was only in lateral incisors (p<0.01) 7. The irregularity index of lower incisors showed greater value in crowded group (p<0.01).
Crowns
;
Incisor
;
Malocclusion
;
Statistics as Topic*
;
Tooth
9.Study on masticatory pattern of adult having anterior cross bite.
Byung Wha SOHN ; Hyung Seog YU ; Jong Jin PARK
Korean Journal of Orthodontics 1997;27(1):35-44
mastication is basically regulated by central pattern regulator(CPG) of brain system target organ output from CPG is modulated by oral sensory feedback. anterior cross bite pattern infuluence the feedback mechanism and change muscle activity and jaw movement. .The purpose of this study was to investigate diffemce anterior cross bite group from normal group. the selected sample groups were 30 normal patient, 30 anterior cross bite patient. EMG and EGN of Biopak system were used for this study The following results were obtained 1. In resting state of mandible, anterior cross-bite showed the high r muscle activities in all the muscle.(exeeption:left digastric muscle) than normal group. 2. In clenching state, No significant difference in muscle activities of normal group and anterior cross bite group was noticed 3. In swallowing state Normal group showed the higher muscle activities in left and right masseter muscle, right posterior temporal muscle. 4. In maximum opening and closing velocity, normal group showed the higher value than anterior cross-bite. 5. In the mean value of the maximum operiing,the maximum anterior-posterior movement from centric-occlusion, the lateral deviation from centric-occclusion, normal group showed the higher value than anterior cross-bite group.
Adult*
;
Brain
;
Deglutition
;
Feedback, Sensory
;
Humans
;
Jaw
;
Malocclusion*
;
Mandible
;
Masseter Muscle
;
Mastication
;
Temporal Muscle
10.An analysis of stress distribution in the case of unilateral molar expansion with precision lingual arch by finite element method.
Korean Journal of Orthodontics 1994;24(3):721-733
Orthodontic tooth movement is closely related to the stress on the periodontal tissue. In this research the finite element method was used to observe the stress distribution and to find the best condition for effective tooth movement in the case of unilateral molar expansion. The author constructed the model of lower dental arch of average Korean adult and used .032" x .032" x 60mm TMA wire. The wire was deflected in the horizontal and vertical direction to give the 16 conditions. The following results were obtained; 1. When the moment and force were controlled properly the movement of anchor tooth was minimized and the movement of moving tooth was maximized. 2. As the initial horizontal deflection increased the buccal displacement of both teeth was also increased. As the initial vertical deflection increased the lingual movement of anchor tooth and the buccal movement of moving tooth increased. 3. When the initial horizontal and vertical deflection rate was 1.5 the effective movement of moving tooth was observed with minimal displacement of anchor tooth.
Adult
;
Dental Arch
;
Humans
;
Molar*
;
Tooth
;
Tooth Movement