• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.253-261
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• 2009

The purpose of this study was to present new data on the timing and sequence of permanent teeth emergence and to compare these findings with the results of earlier studies. The dental examinations had been performed to E-elementary school students, who visited the Yonsei University Dental Hospital between 1998 and 2005; 1,307 boys and 1,312 girls with the age ranging from 6 to 12 years old. The followings were concluded. 1. Eruption time of the maxillary permanent teeth is as follows. It was 6.81 years in male and 6.73 years in female for the central incisor, 7.78 years in male and 7.65 years in female for the lateral incisor, 10.48 years in male and 9.92 years in female for the canine, 9.76 years in male and 9.63 years in female for the first premolar, 10.66 years in male and 10.49 years in female for the second premolar, 6.39 years in male and 6.26 years in female for the first permanent molar, and 12.13 years in male and 12.03 years in female for the second permanent molar. 2. Eruption time of the mandibular permanent teeth is as follows. The central incisor could not be determined in this study, but it is assumed to erupt before the age of 6.08. In the mandible, eruption time was 6.78 years in male and 6.65 years in female for the lateral incisor, 9.76 years in male and 9.05 years in female for the canine, 9.82 years in male and 9.59 years in female for the first premolar, 10.67 years in male and 10.52 years in female for the second premolar, 6.22 years in male and 6.12 years in female for the first permanent molar, and 11.58 years in male and 11.14 years in female for the second permanent molar. 3. The eruption sequence is as follows. In the maxilla, the first permanent molar erupted first, followed by the central incisor, the lateral incisor, the first premolar, the canine, the second premolar, and the second permanent molar. In the mandible, the central incisor erupted first, followed by the first permanent molar, the lateral incisor, the canine, the first premolar, the second premolar, and the second permanent molar. 4. Tooth eruption occurred earlier in female compared to male by average of 0.19 year in the maxilla and 0.29 year in the mandible. 5. In both male and female, the hiatus (interval of rest) occurred between the emergence of lateral incisor and first premolar in the maxilla while it was observed between the lateral incisor and canine in the mandible. Male had a hiatus of 1.98 years in the maxilla and 2.90 years in the mandible, while the female's were 1.98 years and 2.40 years, respectively.

• Journal of Korean society of Dental Hygiene
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• v.21 no.3
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• pp.319-319
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• 2021

• Journal of dental hygiene science
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• v.2 no.1
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• pp.39-45
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• 2002

Our study shows the following results of the patterns and reality of oral health of 862 Government employees and private school employees who had received oral examinations from April to May, 2000. For the exposition of each group to dental service, the male groups(37.4%) were more exposed than the female ones(30.0%, p<0.05), while the scaling experience results indicated that more ages mean more scaling(the over 50 year group 27.1%, 41-50 group 23.9%, 31-40 group 20.5%, 21-30 group 10.8%, p<0.001). The data involving sweet food and refreshments revealed that 'positive respondents' in the male groups were 19.7% with 12.5% positive in the female ones, and 'negative respondents' were 32.3% and 51.0% in the male and female groups respectively(p<0.001). For the oral odor, the male groups(37.9%) are more severe than the female ones(25.5%, p<0.01). The results of dental caries revealed that 19.1% of the male and 13.9% of the female said 'yes'(p<0.05), with 25.1% of the male and 11.1% of the female suffering from missing teeth(p<0.001); 77.4% of the male and 51.0% of the female from periodontal disease (p<0.001).

• The korean journal of orthodontics
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• v.27 no.2
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• pp.181-196
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• 1997

The purpose of this study was to describe growth changes of soft tissue profile in koreans with normal occlusion and to get differences between male and female. The biennial serial cephalometric radiographs of 26 samples (15 males, 11 females) with normal occlusion from 8.5 years to 18.5 years of age were used in this study. The following results were obtained : 1. Both sexes had lower facial parts more protruded at 18.5 years of age than 8.5 years of age : in total facial convexity angle, male showed a decrease(P<0.01) and female showed no significant difference(P>0.05). 2. In the growth changes of soft tissue thickness, male outgrew female in the areas of nose and upper and lower lips, and female outgrew male in the pogonion area 3. In the growth changes of upper facial height and upper part of lower facial height, male's was higher than female's growth (P<0.05). 4. The ratio of the upper facial height over the lower facial height showed a decrease at 18.5 years of age than 8.5 years of age(P<0.01). The ratio of upper vs lower part of lower facial height and that of upper lip height vs lower lip height showed no significant difference(P>0.05). 5. Male showed a sustained change into older age compared with female in soft tissue profiles.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.312-319
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• 2020

Precocious puberty (PP) is defined as the early development of secondary sexual characteristics (before the ages of 8 years in girls and 9 years in boys). The aim of this study is to identify characteristics of the dental maturity in girls with PP that discriminate them from normal healthy girls. This study included 99 girls aged 6 - 8 years with PP and 99 girls without past medical history of same chronological age (control group). The study was performed on 198 panoramic radiographs (99 PP girls, 99 control group girls). Demirjian method was used to evaluate the panoramic radiographs and determine dental maturity. Difference in dental maturity score and tooth formation stages between the two groups were analyzed. The PP group showed significant higher maturity score than control group. Among mandibular teeth, mandibular 2nd premolar and 2nd molar were significantly more mature in the PP group than control group. Logistic regression analysis showed that mandibular 2nd molar was only significant predictor for PP girls.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2150-2159
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• 2014

This study was designed to investigate the status of orthodontic treatment and facial plastic surgery among 389 patients who visited dental clinics located in Seoul and Gyeonggi Province. After the collection of data, an analysis was carried out using a spss statistical program. The analysis results are as follows. the level of satisfaction with orthodontic treatment from patients with experience of the orthodontic treatment turned out to be high(p<0.01). Women considered 3.01 to 4 million won to be reasonable cost for orthodontic treatment (p<0.05), which is higher cost recognized by men, and patients with experience of orthodontic treatment recognized 19 to 24 months as the proper orthodontic treatment period(p<0.01). In addition, women showed higher figures than men in their awareness on the need for orthodontic treatment checkups(p<0.001), and facial plastic surgery experience (p<0.01). With respect to the part of the face on which they hoped to have plastic surgery, eye plastic surgery was higher in women (p<0.01), and nose surgery turned out to be higher in patients with experience of orthodontic treatment(p<0.05). Meanwhile, women considered the eye as the most important part among other facial areas (p<0.001), and they recognized that dentist should perform plastic surgery on both jaws among facial areas(p<0.01). In conclusion, the dental medical staff should provide consultations and operate treatment systems in consideration of gender differences and needs of dental patients. In the case of orthodontic treatment for the improvement of facial appearance, especially double jaw surgery which is closely related to the oral function, professional dental medical staff needs to perform the operation, considering the special oral environment. In addition, it is determined that provision of relevant medical information and promotion of dental service is required to provide patients with correct knowledge about orthodontic treatment and facial plastic surgery.

• The korean journal of orthodontics
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• v.32 no.1 s.90
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• pp.33-42
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• 2002

This study was performed to compare the pattern of dentoalveolar characteristics in different vertical and anteroposterior skeletal types in skeletal Class III malocclusion. The samples selected for this study were consisted of 60 subjects(29 males and 31 females, mean age; 19.7 years) in Class III group, 43 subjects(14males and 29 females, mean age : 20.5 years) in normal group. The findings of this study were as follows : 1. The IMPA of the Class III group was smaller than that of the Class I group(p<0.01). 2. In the Class III groups, SNB and NtoPog had negative correlation with IMPA(p<0.01). The SNB and NtoPog had correlations with SNU1, FHU1 and PalU1(p<0.01) in the male samples, and in the female samples, the SNB and NtoPog had correlations with SNU1(p<0.01). 3. In the Class III male samples, SNMP, FMA, PalMP had negative correlation with IMPA(p<0.01). SNMP, FMA, PalMP had not significant correlation with SNU1, FHU1, PalU1. In the Class III female samples, FMA, PalMP had negative correlation with IMPA(p<0.01). 4. In the high angle group of Class III samples, SNU1, IMPA is smaller than that of low angle group of Class III samples(p<0.05).

• Journal of Korean society of Dental Hygiene
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• v.18 no.6
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• pp.863-878
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• 2018

Objectives: The purpose of the study was to investigate the regional distribution and working environment of clinical dental hygienists in Korea. Methods: From 2015 to October 2016, a questionnaire was completed by 5,708 participants and the data were analyzed. Results: The region with the largest increase in clinical dental hygienist employees compared to graduates is Seoul. More than 50.0% of clinical dental hygienists working for less than 1.8 million won in the payroll period of 4-6 years were working in the Gwangju Jeonnam, Jeonbuk, and Gangwon regions. In addition, incentives and bonuses were rarely provided by localities and agencies. Although 43.4% provided both parental leave and maternity leave. Conclusions: In order to solve the fundamental problem of inter-regional movement and employee turnover rate of clinical dental hygienists, as well as address the regional imbalance in labor supply and demand, efforts should be made for institutional improvement to strengthen management and implementation.

• Journal of Korean society of Dental Hygiene
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• v.18 no.6
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• pp.1057-1066
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• 2018

Objectives: The purpose of this study is to provide a reference material for improving the work environment to reduce the turnover intention of clinical dental hygienists in the future by identifying the problem of the turnover phenomenon of clinical dental hygienists in Seoul and Gyeonggi-do. Methods: The method of this study used the raw data of 'A Survey on the Current Work Environment of Clinical Dental Hygienists' from August 29 to September 28, 2017, and 2,974 clinical dental hygienists in Seoul and Gyeonggi-do were finally selected as the study subjects. Results: The results showed that excessive workload, inadequate pay, and hierarchical organizational culture of a workplace were the main factors influencing the turnover intention of clinical dental hygienists, and the lack of welfare system, low wage and practical experience also affected their turnover intention. Conclusions: In order to reduce the turnover intention of clinical dental hygienists, it is important to create a working atmosphere where the members of an organization can freely share and communicate suggestions and improvements, and to pay their salary appropriate to the duties and roles of dental hygienists, and accordingly they will be able to carry out the duties with responsibility for a long time without moving to another organization.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.31-41
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• 2021

The aim of this retrospective study was to evaluate the correlation between the midpalatal suture maturation and skeletal maturation in growing children aged 7 - 15 years and predict the maturational stages of the midpalatal suture corresponding to skeletal maturity assessed by the skeletal maturation indicators (SMI) and middle phalanx of the third finger (MP3) stages. The group of this retrospective study was consisted of randomly selected 132 male and 135 female in age from 7 - 15 years. The maturation of the midpalatal suture was evaluated by using images from cone-beam computed tomography (CBCT) while the skeletal age was assessed by hand-wrist radiography. CBCT images and hand-wrist radiographs used in this study were obtained from all subjects for orthodontic diagnosis before orthodontic treatment. The maturational stages of the midpalatal suture showed strong correlations with both SMI and MP3 stages. The correlation between the midpalatal suture maturation and SMI (Spearman's correlation coefficient, ϒ_S = 0.905, p < 0.05) was slightly greater than that of MP3 stages (ϒ_S = 0.830, p < 0.05). There was a positive significant correlation between the midpalatal suture maturation and chronological age (ϒ_S = 0.868,p < 0.05). CBCT for evaluation of the midpalatal suture maturational stages may be unnecessary in every pediatric patients because SMI and MP3 stages were both replaceable useful methods for assessing maturation of the midpalatal suture before orthopedic treatment. In this retrospective study, the diagnostic reliability of the SMI method for estimating midpalatal suture maturation showed better reliability than the MP3 method.