• The korean journal of orthodontics
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• v.25 no.4
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• pp.447-451
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• 1995

The purpose of this study was to investigate the effects of cleft on mesiodistal dimensions of permanent teeth in unilateral cleft lip and palate patients. Mesiodistal dimensions of permanent teeth were measured to the nearest 0.01mm on plaster models of 50 subjects with unilateral complete cleft lip and palate, 10 siblings and 50 Controls. The results were as follows : 1. Tooth size discrepancy in the cleft group was significant in all regions except maxillary cuspid, mandibular cuspid and mandibular first premolar. 2. Some of the mesiodistal dimensions of the teeth on the cleft side were significantly smaller than those of their antimeres on the non-cleft side in the cleft group. 3. A comparison of mesiodistal dimensions of the teeth for the right and left sides of the control group showed no statisically significant differences excepts maxillary lateral incisor. 4. Asymmetries of mesiodistal dimensions of the teeth in the sibling group was not found except maxillary first molar.

• The korean journal of orthodontics
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• v.15 no.2
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• pp.341-352
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• 1985

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 individuals (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 sliding calipers (Mitutoyo Co.). From the study, the results are as follows; 1. Sex differences of mesiodistal won 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 incisors and lateral incisors in the decidous teeth and the successional permanent teeth were $7.20{\pm}1.79mm$ in upper, $5.38{\pm}1.64mm$ in lower and that of canine,1st molar and 2nd molar in the deciduous teeth and the successional permanent teeth were $0.56{\pm}1.19mm$ in upper, $2.22{\pm}1.19mm$ 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.

• The korean journal of orthodontics
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• v.11 no.1
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• pp.31-34
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• 1981

A study of a sample of 81 Korean adolescents was taken to determine the degree of correlation between mandibular anterior teeth size and the size of the canines and premolars. The correlation between the total mesiodistal width of the mandibular permanent incisors and that of maxillary or mandibular canine and first and second premolars was found to be 0.53 and 0.58, respectively. Further , regression constants were determined in an attempt to estimate the buccal segments from the mandibular incisors.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.502-509
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• 2003

After 800 students of Chonbuk National University was examined, 86 people (male : 43, female : 43, mean age : 22.2 years old) was selected as a group of normal occlusion. From their gypsum cast, this conclusion was obtained. 1. Intra-observer measurement errors in buccolingual diameter, maxillary lateral incisors have somewhat bigger errors. In mesiodistal diameter, maxillary first molars and maxillary second molar have bigger numerical value. Mean errors of measurement are 0.051mm at buccolingual diameter of crown and 0.083mm at mesiodistal diameter. 2. Fluctuating asymmetry is 0.030 average in buccolingual diameter, and 0.037 average in mesiodistal diameter. Statistically there are no big differences. 3. Male has longer buccolingual diameter than female in every permanent teeth. Teeth which have statistical difference in buccolingual diameter are maxillary lateral incisor, maxillary canine, maxillary second molar, mandibular central incisor, mandibular canine, mandibular second premolar, and mandibular first molar. In mesiodistal diameter maxillary central incisor, maxillary canine, and mandibular first molar have statistically difference. 4. Tooth which has the biggest difference depending on gender is maxillary lateral incisor in buccolingual diameter and mandibular canine in mesiodistal diameter. 5. Both sexes have similar crown index. Male has bigger value of crown module measurement and crown area measurement in every tooth. Crown area considered as size of tooth from occlusal surface was bigger in male than in female statistically except some teeth, maxillary first premolar, mandibular lateral incisor, first premolar and second premolar.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.2
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• pp.253-261
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• 2006

Estimating the size of unerupted teeth is an essential aspect of orthodontic diagnosis and treatment planning in the mixed dentition. Several methods were introduced and used for the prediction. The most common methods among these would be Moyers probability chart and Tanaka and Johnston equations. These are currently used widely, but they were developed for Caucasians. Because there are clear racial differences in teeth size, the objectives of this study were to produce correlation coefficients between the combined mesiodistal widths of the permanent mandibular incisors and those of the canines and premolars for each quadrant, and prediction tables with regression equations, specifically for Korean. 178 young adults (70 women, 108 men, mean age 21.63 years) were selected from the College of Dentistry, Yonsei University, Seoul, Korea. The mesiodistal crown diameters of the permanent teeth were measured with calipers. Significant sexual dimorphism was found in tooth sizes. The correlation coefficients between the total mesiodistal width of the mandibular permanent incisors and those of the maxillary and mandibular canines and premolars were found to be between 0.52 and 0.64. The standard error of the estimatation was better (0.60) for women and the ${\gamma}^2$ values ranged from 0.27 to 0.41 for both sexes Prediction tables were prepared for Korean. This study showed larger canine and premolar diameters than Tanaka and Johnston's and Moyers' studies which might be due to the racial differences. Further investigations with a larger sample size will be needed for more representative data on the Korean population.

• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.217-225
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• 1988

This study was undertaken to examine relationship between tooth size and arch dimension in dental crowding. Two groups of dental casts were selected on the basis of dental crowding. One group, consisting of 51 pairs of dental casts (24 male and 27 female), exhibited remarkable dental crowding. A second group, consisting of 60 pairs of dental casts (30 male and 30 female), exhibited little or no crowding. Mean and standard deviation of the following parameters were used to compare two groups. individual and collective mesiodistal tooth diameters, buccal and lingual arch widths and arch area. The following results were obtained. 1. The crowed group revealed larger tooth size than noncrowded group. (p < 0.01) 2. The crowded group smaller maxillary dental arch dimension than noncrowded group except lingual arch width at canine region. (p < 0.01) 3. The corwded group revealed smaller mandibular dental arch dimension than noncrowded group except lingal arch width at second premalar region in the male and buccal arch width at canine, premolar region in the female. (p < 0.01) 4. The crowded group revealed smaller arch area than noncrowded group in the female (p < 0.01), but there was no significance in the male.

• The Journal of the Korean dental association
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• v.48 no.3
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• pp.196-204
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• 2010

To establish the ideal occlusal relationship, the values of tooth size and ratio must be in a normal range. In this study, the means and standard deviations of Bolton's anterior ratio and overall ratio using mesiodistal dimensions of teeth measured on diagnostic models of 334 Korean malocclusion patients were calculated and differences in Bolton ratio according to the groups of malocclusion patients were studied. Also the changes that can occur in overall ratio before and after hypothetical tooth extractions were observed. The results are as follows. 1. The mean anterior ratio of Korean malocclusion patients was $78.0\;{\pm}\;2.69%$, and the mean overall ratio was $91.56\;{\pm}\;2.28%$. 2. The largest value of tooth size ratio could be found in Class III group, followed by Class I and Class II groups in order. However there was no statically significant difference. 3. The values of overall ratio reduced significantly after premolar extractions in all malocclusion groups, which was much more significant in the extraction of upper second premolar and lower first premolar(U5L4) or upper second premolar and lower second premolar(U5L5). 4. The values of overall ratio reduced significantly after premolar extractions in all 3 groups divided based on Bolton ratio, which was much more significant in the extraction of upper second premolar and lower first premolar(U5L4) or upper second premolar and lower second premolar(U5L5).

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.157-167
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• 2003

The purpose of this study was to find whether there is a correlation between tooth size and jaw size. Dental stone models and cephalometric radiographic films of 87 untreated individuals were evaluated. Repeated measurements of the maximum mesiodistal width of the teeth were taken by means of a digital vernier caliper. Linear measurements of jaw size were assessed by means of a digitizer and Visual C++ program. All measurements were taken separately according to the subject's gender. To determine the relationship between jaw and tooth size, the Pearson correlation was used. The results were as follows: 1. Male and female subjects showed a statistical difference in regard to tooth size and jaw size 2. In contrast to the results of the male subjects, there were no statistically significant correlations between maxillary size and maxillary teeth size in female subjects 3. In male subjects, the two maxillary sizes of PTM vert-ANS vert (FH plane) and PTM vert-A yen (palatal plane) were significantly correlated with themaxillary teeth size. Especially, the size of the upper central incisor showed significant correlation with all maxillary sizes. 4. In both male and female subjects, mandibular size B vert- Point J vert (mandibular plane) showed significant correlation with mandibular teeth size. As gleaned kom the results of this study, the relationship between jaw size and tooth size was fair or little in natural occurring good occlusion.

• The korean journal of orthodontics
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• v.34 no.6 s.107
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• pp.488-496
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• 2004

The purpose of the present study was to investigate the relationship of dental crowding to tooth size and arch dimension in Korean subjects. Two groups of dental casts with Class I molar relationship, were selected on the basis of crowding. One group, consisting of 82 pairs of study cast (29 males and 53 females), exhibited at least 7 millimeters of crowding in each arch. A second group, consisting of 82 sets of study cast (37 males and 45 females), exhibited normal occlusion with little or no crowding. Mesiodistal tooth diameters, and buccal and lingual dental arch widths were measured and compared between the crowding and normal occlusion groups. Significant differences were observed between the two groups not only in arch widths but also in tooth sizes. The results of the present study suggest that both extraction and expansion can be used as a treatment approach for the crowding cases.

• The Journal of the Korean dental association
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• v.48 no.12
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• pp.868-879
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• 2010

Adjunctive orthodontic therapy may be required to create appropriate space, to address misalignment and tooth size discrepancy for better function and esthetics. The desired interproximal alveolar contour and gingival embrasure form can be developed during treatment. Various applications of temporary anchorage devices for pre-prosthetic tooth movement allowed clinicians to achieve high efficiency, shorter treatment time, and less discomfort of patient. Biomechanical considerations for the periodontal status of the affected teeth are required to successfully control the vertical and horizontal space. Hence, the interdisciplinary approaches have an essential role in maximizing the favorable treatment outcome. In particular, pivotal Clinical decisions such as whether to open or close the space should be made by consensus of the involved dentists. This article presents the orthodontic treatment approaches for prosthodontic works including mesiodistal and vertical space regaining specially for cases of unrestored teeth over an extended period of time.