No abstract available.
Malocclusion*

No abstract available.
Malocclusion*

Variation in the facial pattern and effect of the rotational jaw growth on the facial proportion were studied in serial cephalometric radiographs of 40 Korean children (35 boys, 15 girls) ranging in age from 6 to 13 years. According to Y-axis (N-S-Gn) growth change during the 7 years of period, the subject who had exhibited "wave-like" manner of Y-axis growth change within +/- 2degrees was classified to the Parallelwise group and the subject who had exhibited Y-axis increase more than +/- 2degrees was classified to the Clockwise rotation group and the subject who had exhibited Y-axis decrease more than -2degrees was classified to the Counterlockwise rotation group. For the comparison of each group, a total of 22 morphologic variables were employed and the data were analyzed by means of computer morphometrics and statistical methods. On the basis of the finding of this study, the following trends were eatablished: 1. The Parallelwise group was 75%, the Clockwise rotation group was 12.5% and the Counterclockwise rotation group was 12.5%. 2. The growth pattern of cranial base was related to the rotation of mandible. 3. Maxillary prognathism was occured in the Counterclockwise rotation group and the rotation of palatal plane was occured in the Clockwise rotation group. 4. Mandibular prognathism was occured in the Parallelwise and the Counterclockwise rotation groups, especially in the Counterclockwise rotation group. 5. The degree of maxillo-mandibular divergency was constant in the Clockwise rotation group but decreased in the Counterclockwise rotation and the Parallelwise groups, especially in the Counterclockwise group. 6. There were no differences in the size of the anterior upper facial height (N-ANS) and the posterior lower facial height ((Go-Me)-PNS) but there were differences in the size of the anterior lower facial height (ANS-Me) and the posterior upper facial height ((S-N)-PNS) between each group. 7. The growth increment and the size of the facial gepth was not relater to the growth pattern of the face but the growth increment and the size of the facial height was related to the growth pattern of the face. 8. Proportional change due to the facial growth rotation was concentrated in the anterior lower face. 9. The most apparent difference between each group was happened in the size of the posterior cranial base (S-Ba) and the facial length (S-Gn).
Child ; Humans ; Jaw ; Mandible ; Prognathism ; Skull Base

The purpose of this study was to investigate the root resorption and repair pattern of human teeth according to the force magnitude, direction and duration during the initial leveling and alignment phase. 40gms to 500gms of force applied to the 37 experimental teeth with duration of 3 weeks to 7 months. Then, the experimental teeth were extracted. 13 control teeth were extracted without treatment. The results are as follows: 1. 59.5% of 37 teeth exhibited root resorption. The initial resorption site was visible at the apex within 3 weeks with 100 gins samples, and the initial repair site was visible at the apex within 3 months with 400 gms samples. 2. Number of resorbed teeth increased with the duration of the force. 3. The depth of the resorption increased with the magnitude of the,force. 4. The areas of resorbed root corresponded with the loading pattern. 5. The areas of resorbed root were highly correlated with the magnitude of the force. The result of this study suggest that root resorption could occur during the initial leveling and alignment phase. These initial injuries are all small and insignificant. It is the extensive type of apical root resorption that must be regarded as deleterious to the function and stability of the tooth moved. During the initial leveling and alignment phase lighter force of the interrupted type and short treatment period would be favorable with regard to avoidance of root resorption and repair of resorbed root surface.
Humans ; Microscopy, Electron, Scanning ; Orthodontics* ; Root Resorption ; Tooth

The present paper describes 3 clinical cases in which the orthodontic, treatment was effected by the Bioprogressive therapy following the extraction of the upper and lower first premolars. What is most noteworthy in the present treatment is the use of a systems approach to diagnosis and treatment by the application of the visual treatment objective in planning treatment, evaluating anchorage and monitoring results, and the rest being performed routinely by Bioprogressive mechanism. The result achieved by this method is very favorable and the efficiency of the Bioprogressive therapy is quite satisfactory.
Bicuspid ; Diagnosis ; Malocclusion*

The primary objective of this study is to estimate of the mesiodistal crown diameters of the unerupted permanent successors derived from the mesiodistal crown diameters of the deciduous teeth in Korean population. The subjects were 54 indiciduals (twenty nine boys and twenty five girls) with normal occlusion aged 6 to 13 years. The mesiodistal crown diameters of the deciduous and the successional permanent teeth were measured from the longitudinal dental cast models using the shding calipers (Mitutoyo Co.) From the study, the results are as follows, 1. Sex differences of mesiodistal crown diameters were less in the deciduous teeth, but male were more than that of female in the successional permanent teeth. 2. The mesiodistal crown diameters of the deciduous central incisors, lateral incisors, canines were smaller than that of the successional permanent teeth and the deciduous 1st molars, and 2nd molars were more larger than that of the successional permanent teeth. 3. Size differences between sum of the mesiodistal crown diameters of central meisors and lateral meisors in the decidous teeth and the successional permanrnt teeth were 7.20 +/- 1.79 mm in upper, 5.38 +/- 1.64 mm in lower and that of canine, 1st molar and 2nd molar in the deciduous teeth and the successional permanent teeth were 0.56 +/- 1.19 mm in upper, 2.22 +/- 1.19 mm in lower. 4. In male, the correlation coefficients between the upper deciduous central incisor and the successional permanent tooth (r=0.57) and in female, the correlation coefficients between the upper deciduous 1st molar and the successional permanent tooth (r=0.67) appeared the highest. 5. The regression constants were determined to estimate the mesiodistal crown diameters of the unerupted successional permanent teeth.
Crowns* ; Female ; Humans ; Incisor ; Male ; Molar ; Sex Characteristics ; Tooth* ; Tooth, Deciduous

A serial cephalometric study was undertaken to define the growth of the soft tissue facial profile in Korean children. The sample was composed of 25 males and 15 females for whom yearly cephalometric records were taken from the ages of 6 to 13 years. From the tracings, points on skeletal and soft tissue profiles were located and recorded on magnetic tape utilizing a Calcomp Talos RP660 X-Y digitizer. Linear and angular measurements of soft tissues were made directly from tape in a Cyber 174-16 computer after cephalometric enlargement had been corrected. A statistical evaluation was made of the data and the average profile diagrams in male and female were described by a Calcomp 960 pen plotter. On the basis of the findings of this study, the following trends were established. 1. The most prominent growth in soft tissue facial profile thickness was the nose and the least was the forehead. 2. The general growth direction of the soft facial tissue to the cranium described the downward and forward. 3. The degree of soft tissue facial convexity was decidely more than that exhibited earlier in life even though the soft tissue chin had protruded to the cranium. 4. The measurements indicated a general tendency for males to have larger nose and more convex and long soft tissue facial profile than did females. 5. Males showed significantly more growth than females in base of the upper lip and height of the upper anterior facial profile. 6. There was a difference between males and females in the rates of soft tissue facial profile growth. 7. Korean children showed less convex in the soft tissue profile convexity than did American children.
Child* ; Chin ; Female ; Forehead ; Humans ; Lip ; Longitudinal Studies* ; Male ; Nose ; Skull

This study was undertaken to analyze the displacement and stress distribution in the mandible according to the pulling directions during mandibular first molar cervical traction after mandibular second molar extraction. The 3-dimensional finite element method(FEM) was used for a mathematical model composed of 594 elements and 1019 nodes. An orthodontic force, 450gm, was applied to the each mandibular first molar in parallel, and below the occlusal plane by 7degrees and 25degrees and meet the midsagittal plane by 40degrees toward posterior direction. The results were as follows: 1. Mandibular teeth were displaced in more downward, posterior and lateral direction. Especially high stress was noted in case of parallel pull than in case of below the occlusal plane by 7degrees and 25degrees. 2. Mandibular first molar was moved bodily. 3. Generally, alveolar bone, mandibular body, ascending ramus and mandibular angle portion were displaced in downward, posterior and lateral direction. But coronoid process was displaced in downward, forward and lateral direction, and anterior and inner middle portion of condyle head and neck were displaced in downward, forward and medial direction, and posterior and outer middle portion of condyle head and neck were displaced in upward, forward and medial direction. 4. Maximum stress was observed at the condyle head and neck portion. With steeper direction of force, condyle head and neck showed more stress than parallel relation to the occlusal plane.
Dental Occlusion ; Finite Element Analysis* ; Head ; Humans* ; Mandible* ; Models, Theoretical ; Molar* ; Neck ; Tooth ; Traction*

It is the aim of this study to investigate the effects of sodium fluoride and sodium orthovanadate upon the proliferation and activity of the osteoblast (MC3T3-E1 cells). MC3T3-E1 cells were cultured in alpha-MEM containing 10% FBS and various concentration of sodium fluoride and sodium orthovanadate was appended to serum free media. DNA synthesis was examined through the [3H] thymidine incorporation into DNA. Collagen synthesis was examined through the [3H] proline incorporation into collagenase digestible protein and noncollagen protein. The following results were drawn; 1. Sodium fluoride stimulated the DNA synthesis of osteoblast significantly in dose-dependent manner within the concentration from 2micrometer to 10micrometer (P<0.005). 2. Sodium orthovanadate stimulated the DNA synthesis of osteoblast significantly in dosedependent manner within the concentration from 2micrometer to 8micrometer, however showed diminution at 10micrometer (P<0.001). 3. Sodium fluoride and sodium orthovanadate stimulated the percent collagen synthesis of osteoblast significantly in dose-dependent manner within the concentration from 5micrometer to 10micrometer (P<0.001). 4. Sodium fluoride and sodium orthovanadate stimulated the non collagen synthesis of osteoblast significantly in dose-dependent manner within the concentration from 5micrometer to 10micrometer (P<0.001). In conclusion, sodium fluoride and sodium orthovanadate stimulate the proliferation and activity of osteoblast by stimulation of DNA synthesis and collagen and noncollagen synthesis in osteoblast.
Cell Line* ; Collagen ; Collagenases ; Culture Media, Serum-Free ; DNA ; Osteoblasts* ; Proline ; Sodium Fluoride* ; Sodium* ; Thymidine ; Vanadates*

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 patterns, 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 and 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 summerizcd 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.
Axis, Cervical Vertebra ; Female ; Humans ; Male ; Mandible ; Maxilla ; Skull Base