• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.2
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• pp.365-374
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• 1996

The prupose of this study was to obtain standard measurements of the tooth size, Bolton ratio, width and length of dental arch and basal arch, overbite and overjet of the children who have normal dentition. The plaster cast of 97 children(47 boys and 50 girls) among the contestants in 1992, 1994, 1995 Healthy Dentition contest in Seoul were measured and following results were obtained. 1. Means and standard deviations of the mesio-distal maximum width of the permanent teeth, Bolton ratio, width and length of the dental arch and basal arch of the upper and lower dentition and overbite and overjet of the children were obtained. 2. Mesio-distal width of the teeth, width and length of the dental arch and basal arch of the upper and lower dentition of the boys were larger than those of the girls. 3. Bolton Overall ratio, Anterior ratio and overjet of the boys were larger than those of the girls and overbite of the boys were smaller than those of the girls, but no significant differences were noted between the boys and the girls(p>0.05). 4. In the comparision of the Healthy Dentition Contestants with Korean adults of Shur, all teeth of the Contestants were larger than those of Korean adults, especially upper and lower bicuspids(p<0.01). In the comparision of the Healthy Dentition Contestants with Caucasians, all teeth except upper and lower central incisor and upper first molar of the contestants were larger than those of Caucasians(p<0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.6
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• pp.553-560
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• 2008

STATEMENT OF PROBLEM: Proximal contact plays an important role in the stability and maintenance of the integrity of the dental arches. However, it is difficult to evaluate quantitatively the tightness of proximal tooth contact (TPTC). PURPOSE: The aim of this study was to measure the TPTC in permanent dentition. MATERIAL AND METHODS: Ten young adult volunteers with healthy dentition participated in this experiment. The TPTC between the teeth of both the maxilla and the mandible was measured at rest state by a novel device which records the TPTC by pulling of a stainless steel strip (0.03 mm thick) using the electric motor. One-way ANOVA test was used to compare the values in all measured area. When a statistically significant difference was calculated, Bonferroni correction was applied. Independent samples t-test was used to compare the values in male and female. RESULTS: The lowest TPTC and the highest TPTC was measured between the lower central incisors (0.87 ${\pm}$ 0.20 N), and between the lower left first molar and second molar (1.99 ${\pm}$ 0.68 N), respectively. All TPTC per quadrant demonstrated a similar pattern of a continuous increased gradient in an anterior-posterior direction. There are no significant difference between the maxilla and mandible. CONCLUSION: The TPTC was measured quantitatively by a novel device and decreased progressively in a posterior-anterior direction.

• The korean journal of orthodontics
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• v.19 no.3
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• pp.49-58
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• 1989

The permanent second molars, erupted about 12-13 years old, are finally erupted except wisdom teeth. Although they are likely to be excluded in the orthodontic treatment because located in the most posterior area of the dentition, about twenty percents of the orthodontic patients have abnormal occlusion of the permanent second molars, and we usually observed the malalignment of the permanent second molars in the finished case without including this teeth. These permanent second molars should be necessarily corrected by orthodontic appliances for the dynamic-normal occlusion. Moreover, according to the previously mentioned treatment philosophy, there are clear advantages in the cases which the permanent second molars were used for anchorage source, and this has been proposed convincingly by many authers. Therefore it is reasonable that orthodontists determine to include the permanent second molars among orthodontic treatment, but particular cases.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.678-685
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• 2006

A certain width of attached gingiva is required to maintain gingival health The purpose of this study was to examine the dimensional changes in the width of attached gingiva and the depth of gingival sulcus among the deciduous, mixed and permanent dentitions and establish baseline information on the width of attached gingiva in Korean children. Eighty-eight children aged 4 to 14, who visited the Department of Pediatric Dentistry at Samsung Medical Center, were selected and divided into 3 groups according to the periods of dentition: deciduous, mixed and permanent dentitions. The width of keratinized gingiva and the depth of gingival sulcus were measured in each group with a periodontal probe and the width of attached gingiva was determined. The width of attached gingiva in maxillary and mandibular first molars increased significantly with age after eruption in the permanent dentition (p<0.05). The sulcus depth significantly increased in newly erupted permanent teeth with narrower width of attached gingiva (p<0.05) in all of the experimented teeth with the exception of the mandibular central incisor during the transition period. The results suggest that the mean width of attached gingiva does not increase steadily from the deciduous to the permanent dentition.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.1
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• pp.11-19
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• 2017

The purpose of the study was to investigate the distribution of primary fused teeth and identify the correlation between primary fused teeth and their effect on permanent dentition. 2575 children between the age of 4 and 6 in Kyungpook National University Hospital from January 2009 to August 2015 were investigated. A total of 84 children (46 boys and 38 girls) had fused teeth. 14 of these children had two fused teeth. Prevalence of caries involvement was in 65% of maxilla and 6% of mandible. Prevalence of permanent successors missing was 86.3% in the cases involving maxillary central and lateral incisor, 70% in mandibular lateral incisor and cuspid, 11.7% in mandibular central and lateral incisor. 27 of 84 children (32.1%) had supernumerary teeth. The highest prevalence rate is seen in the cases involving maxillary central and lateral incisor. Delayed permanent tooth eruption was only observed in the maxilla because of developing supernumerary tooth. Early diagnosis of fused tooth in the primary dentition can allow the dentist to make treatment plan at the appropriate time in accordance with the tooth arrangement and tooth development.

• Journal of Korean Academy of Oral Health
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• v.41 no.4
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• pp.296-302
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• 2017

Objectives: The water fluoridation program has been implemented since 2008, in a region of Geoje City. This study aimed to evaluate the effectiveness of the water fluoridation program on caries prevention in the permanent dentition. Methods: Evaluation surveys were conducted on 8-, 10- and 12-year-old children in the fluoridated and non-fluoridated regions of Geoje City, in 2015. The survey included 834 children from the fluoridated regions and 703 from the non-fluoridated regions. The data obtained from the survey were analyzed using the IBM SPSS statistical package version 23.0. The effectiveness of community water fluoridation in caries prevention was estimated by the differences in the decayed, missing, filled teeth (DMFT) and decayed, missing, filled surfaces (DMFS) scores, between the program and control groups. The mean numbers of fissure-sealed teeth and surfaces were adjusted to reduce their confounding effect. Results: The mean DMFT and DMFS scores (0.69 and 0.91, respectively) of 10-year-olds from the fluoridated regions, after adjusting for the numbers of fissure-sealed teeth and surfaces, were significantly lower than those of the 10 year olds (DMFT: 0.95, DMFS: 1.32) from the non-fluoridated regions. The effectiveness of water fluoridation on caries prevention in the permanent dentition, estimated based on the differences in the mean DMFT and DMFS scores, adjusted for the number of fissure-sealed teeth and surfaces, between the program and control groups of 10-year-old children, was 27.4% and 31.1%, respectively. Conclusions: These results suggest that the effectiveness of water fluoridation on caries prevention in the permanent dentition, in Geoje City was so high that this program should be implemented in other regions in Korea as well.

• The korean journal of orthodontics
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• v.20 no.1
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• pp.169-179
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• 1990

Utilizing the repelling force of permanent magnet of find out weather it shows the findings of molar intrusion histologically and compares the result with the resin bite plane. As for the experimental animals, 10 cats of completion of permanent dentition with mean weight of 2.2kg which have flat occlusal plane of molar areas were used. I raised the cats under the condition of their being attached with manufactured appliance by direct bonding system and of their wearing vertical chin strap anesthetized for 12-14 hours per day through 5 days. Then, observing the root apex areas with lightmicroscope. The results were as follows; 1. In the group with resin bite plane, osteoblasts and osteoclasts could not find out but could find out periodontal ligment fiber obliquely angulated in the apical and lingual direction. 2. In the group with the permanent magnet, not only the obliquely angulated periodontal ligament fiber but also the osteoclasts at the apical areas were observed.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.700-708
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• 2007

A midline deviation is divided into three types, such as a skeletal midline deviation, a dental midline deviation, and a combination. Among them, the midline deviation which appear in the early mixed dentition without any skeletal problem can be managed differently by the stage of dental development. The location of the permanent incisors can be improved without using artificial force in consideration of the condition of the space, the eruption timing or the eruption path of the adjacent permanent teeth in early mixed dentition, especially when the permanent incisors are erupting. Therefore, the space supervision technique, which can have the teeth align themselves utilizing physiologic events such as sequence or timing of the eruption of permanent teeth, can be an alternative to orthodontic movement. This case report describes midline deviation improvement by space supervision.

• The korean journal of orthodontics
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• v.46 no.3
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• pp.171-179
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• 2016

Objective: The primary aim of the study was to generate new prediction equations for the estimation of maxillary and mandibular canine and premolar widths based on mandibular incisors and first permanent molar widths. Methods: A total of 2,340 calculations (768 based on the sum of mandibular incisor and first permanent molar widths, and 1,572 based on the maxillary and mandibular canine and premolar widths) were performed, and a digital stereomicroscope was used to derive the the digital models and measurements. Mesiodistal widths of maxillary and mandibular teeth were measured via scanned digital models. Results: There was a strong positive correlation between the estimation of maxillary (r = 0.85994, $r^2=0.7395$) and mandibular (r = 0.8708, $r^2=0.7582$) canine and premolar widths. The intraclass correlation coefficients were statistically significant, and the coefficients were in the strong correlation range, with an average of 0.9. Linear regression analysis was used to establish prediction equations. Prediction equations were developed to estimate maxillary arches based on $Y=15.746+0.602{\times}sum$ of mandibular incisors and mandibular first permanent molar widths (sum of mandibular incisors [SMI] + molars), $Y=18.224+0.540{\times}(SMI+molars)$, and $Y=16.186+0.586{\times}(SMI+molars)$ for both genders, and to estimate mandibular arches the parameters used were $Y=16.391+0.564{\times}(SMI+molars)$, $Y=14.444+0.609{\times}(SMI+molars)$, and $Y=19.915+0.481{\times}(SMI+molars)$. Conclusions: These formulas will be helpful for orthodontic diagnosis and clinical treatment planning during the mixed dentition stage.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.345-350
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• 2008

In children with Class III malocclusion, it is important to identify whether the etiology is functional, dental, skeletal. FR-III developed by Rolf Frankel in 1970, has been used during deciduous, mixed, and early permanent dentition to correct class III malocclusion characterized by maxillary skeletal retrusion. According Frankel, the vestibular shields and upper labial pads act to counteract the forces of the surrounding musculature that restrict forward maxillary development and cause a retrusion in maxillary tooth position. This can achieve favorable developments with the basal bone, teeth and alveolar bone. We report FR-III that can be applicated in cases of early mixed dentition with mild maxillary deficiency and deepbite before the eruption of permanent maxillary incisor.