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

Lateral cephalometric X-ray films in maximal intercuspation and maximal opening of 68 children were taken and analyzed to examine the pattern of condylar movement and to study the relationship between opening movement and morphologic factors of craniofacial skeleton. The results were as follows : 1. The mean value of maximal opening capacity was 47.1mm, condylar moving distance was 18.1mm, horizontal condyle movement was 17.5mm, vertical condyle movement was 3.8 mm and condylar moving angle was 13.1degrees. 2. The maximal opening capacity had positive relationship with the length of anterior cranial base, mandible and maxillary complex and with posterior facial height and had negative relationship with articular angle, sagittal jaw relationship. 3. Vertical condyle movement and condylar moving angle had positive relationship with articular angle and had negative relationship with gonial angle. 4. Horizontal condyle movement and condylar moving distance had positive relationship with the length of maxillary complex.
Child ; Humans ; Jaw ; Mandible ; Skeleton* ; Skull Base ; X-Ray Film

The purpose of this study was to investigate the factors which might be related to mandibular third molar eruption and to predict the possibility of whether or not it will be erupted. The material of this study was lateral cephalometric radiograms, pantomograms and dental casts obtained from 70 patients (19 males, 51 females) ranging in age from 18.0 to 32.1 years. They were devided into erupted group and impacted group of mandibular third molars. For the comparison of each group, a total of 20 measurement items were employed and the data were analyzed by means of computer statistical method. As a result of this study, the following conclusion can be made; 1. The longer mandibular body length and narrower mandibular ramus width, the higher eruption tendency of the lower third molar, but the degree of gonial angle was not related to mandibular third molar eruption. 2. The lower percentage of posterior mandibular body height to anterior mandibular body height, the higher eruption tendency of the lower third molar. 3. The total tooth size, including the lower second molar, appeared to be larger in the impacted group than in the erupted group of the lower third molar. 4. The arch length discrepancy of the impacted group was more severe in contrast with the erupted group of the lower third molar.
Body Height ; Humans ; Male ; Molar ; Molar, Third* ; Tooth

This study was aimed to observe the effect of Anterior J hook headgear on the craniofacial structures in mixed dentition with Class II malocclusion. The laterial c-phalograms of 20' children treated by Anterior J hook headgear were traced, digitized and statistically analyzed. The results were as follows 1. Forward growth of maxilla was inhibited. 2. Rotational effect of maxilla was not observed. 3. There was distal movement of maxillary dentition. 4. Maxillary_.dentoalveolar growth changes were more effective in anterior portion than posterior portion. &.Mandible maintained a normal growth and mandibular plane angle- was maintained during treatment period. 6. The ratio of anterior facial height to posterior facial height was almostly not changed.
Child ; Dentition ; Dentition, Mixed ; Humans ; Malocclusion ; Maxilla* ; Traction*

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

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

The objective of this experiment is to observe structural differences in the orthodontic movement of vital (control group) and devitalized (experimental group) teeth in the mongrel dogs. The 5 utilized dogs in this experiment were approximately 1 year of age and their average weight was about 12Kg. Endodontic therapy was performed on the 2nd premolars in upper & lower jaws of each animal under the general anesthesia by intravascular injection of 25mg/Kg of pentobarbital sodium. The canals of the teeth were obturated by using gutta percha in conjunction with root canal sealer (AH26 Densply). One of the roots in the 2nd premolars was hemisected to make an extraction space for the devitalized teeth to be moved. The edgewise technique was employed for the movement of the teeth. Orthodontic models and intraoral roentgenograms were taken before and after orthodontic tooth movement. The open coil springs (.010 x .040) were used at interbraket space in order to provide equal forces (75gm) between the teeth in each arch wire. After 13 weeks of active orthodontic tooth movement, dogs were sacrified and the experimental results were examined through the intraoral radiography, microscopic examination and scanning electromicroscopic examination at the root surface. From the results of the study, the following conclusions may be drawn: 1. The root resorption and cemental deposition were observed within the pressure and tension site in both group. 2. The root resorbed lacunae were observed in the cementum and/or into the dentin in both group. 3. The prominent osteoblastic activities were observed on the alveolar margin in the tension site in both group. 4. A few of blood vessels were observed in the pressure site, but also lots of blood vessels were observed in the tension site especially in the periphery of the alveolar bone in both group. 5. In the pressure site, resorbed lacunae were formed with deep and narrow cavity in the control group; the shallow and wide cavity in the experimental group. 6. In the pressure site, the repaired cementum or cementoid tissue was lined on cementum in the experimental group, but not in the control group. 7. There was no significant difference between external root resorption of endodontically and vital teeth when both were subjected to orthodontic forces.
Anesthesia, General ; Animals ; Bicuspid ; Blood Vessels ; Dental Cementum ; Dental Pulp Cavity ; Dentin ; Dogs* ; Gutta-Percha ; Jaw ; Osteoblasts ; Pentobarbital ; Radiography ; Root Resorption* ; Tooth Movement* ; Tooth* ; Tooth, Nonvital

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