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 observe the effects of sodium fluoride on the bony iepair and regeneration processes after the rapid palatal expansion in the growing dogs. Eighteen dogs were divided into experimental and control groups. They were in the late mixed dentition. The rapid palatal expansion was undertaken in all the animals(180 turn/day) for ten days. The animals were sacrificed on 0, 15 and 45 days; after the finish of expansion. One mg NaF/kg of body weight/day were given orally to the experimental group. Blood sampl, s were drawn before and after expansion and the serum calcium, phosphate and alkaline phosphatase level were measured. The undecalcified bone section of midpalatal suture area was made, and observed under the light microscopy. The results were as follows; 1. The day after expansion, the infiltration of inflammatory cells were prominent and the new bone formation started at the edges of the two palatal plates bodering the midpalatal suture in both groups. Especially, the newly formed osteoid were very extensive and the osteoblasts lining the osteoid were very active in the experimental group. 2. At fifteen days after expansion, the active osteoblasts lining the osteoid at the surface of trabecular bony spicules and active new bone formation were observed in the both groups. However, the cellular activity and new bone formation were more prominent in the experimental group. 3. At forty five days after expansion, the continuous osteoid and new bone formation and active osteoblasts were observed in the experimental group. But these phenomena were not observed in the control group. In the control group, the numerous osteoclasts were adjacent midpalatal suture and the bony remodeling process was begun. The serum alkaline phosphatase level was maintained highly in the experimental group, but decreased in the control. According to the above results, the author reached the conclusion that sodium fluoride has the stimulation effects on the osteoid production of the osteoblasts during the healing process after the rapid palatal expansion more continuously.
Alkaline Phosphatase ; Animals ; Calcium ; Dentition, Mixed ; Dogs* ; Microscopy ; Osteoblasts ; Osteoclasts ; Osteogenesis ; Regeneration ; Sodium Fluoride* ; Sodium* ; Sutures

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

The purpose of this study is to observe the effect of high pull headgear on the craniofacial structures of mixed dentition with Class II malocclusion. The cephalometric headplates of 16 children treated by high pull headgear during 6 months and 18 children during 12 months were traced, digitized and statistically analyzed. The results were as follows. 1. Inhibition of forward growth of maxilla was observed in both group. 2. Clockwise rotation of maxilla was observed in both group. 3. There were distal movement of maxillary 1st molar and inhibition of alveolar bone growth of maxilla. 4. There was compensatory extrusion on mandibular 1st molar. 5. The ratio of anterior facial height to posterior facial height was almostly not changed. In the treatment plan of C II malocclusion by high pull headgear, we must prevent the mandibulasr 1st molar from extruding, and for orthopedic effect, at least 6 months is needed.
Bone Development ; Child ; Dentition, Mixed ; Humans ; Malocclusion* ; Maxilla ; Molar ; Orthopedics

Serial lateral cephalometric radiographs of 40 Korean children(25 males, 15 females) ranging in age from 6 to 13 years were studied by means of computer morphometrics and statistical analysis. As a result of this study, the following conclusions can be made: 1. In both sexes, the mean growth patterns of the face were very stable and the growth directions of the face were more prominent both forward and downward away from the cranial base(S-N). 2. In the mandible, the rotation and the "wave-like" manner of migration were observed. 3. The size of the lateral faces in males was larger than females at 6 and 13 years of age, and the forms of the lateral faces in males were slightly more squared than females at 13 years of age. 4. The sex differences and practical means in the growth increments and gro wth rates during 7 years of the growth period were as follows: (1) In the total face, there was a significant -sex difference:. in the growth increments(males 26.21cm2, females 23.24cm2) and growth rates(males 42.02%, females 39-28%). (2) In the facial surface 1, there was a significant sex difference in the growth increments(males 21.30cm2, females 19.19cm2) but there was no significant sex difference in the growth rates(males 41.35%, females 39.10%). (3) In the anterior total facial height(N-Ne), there was no significant sex difference in the growth increments(males 18.23mm, females 17.45mm) and the growth rates(males 18.44%, females 18.19%). (4) In the posterior total facial height(S-Go), there was a significant sex difference in the growth increments(males 14.61mm, females 12.98mm) but there was no significant sex difference in the growth rates(males 23.78%, females 22.25%). 5. The percentages of anterior upper facial height to anterior total facial height in both sexes were very stable in spite of the age increase. 6. The percentage of total facial height to standing height was reduced by the age increase, and the reduced rate of anterior total facial height(males 13.26%, females 13.75%) was larger than the posterior total facial height(males 9.95%, females 11. 70%). 7. The correlations of lateral facial surfaces to the standing height and the weight were higher in males. than females, but the level of correlation in males was in the moderate range.
Child* ; Female ; Humans ; Longitudinal Studies* ; Male ; Mandible ; Sex Characteristics