• 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.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.632-638
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• 2007

The purpose of this study was to investigate the effect of xylitol chewing gums on mutans streptococci (MS) counts in saliva. Sixty two children 6 to 11 years old were randomly assigned into one of three groups. Stimulated saliva specimens were plated in duplicate on conventional selective culture (mitis salivarius kanamycin bacitracin agar) for mutans streptococci. Polymerase chain reaction (PCR) amplication was performed to identify MS. After the 4-month period a significant decrease of the MS counts occurred in the group B (two gum 3 times a day; P < 0.05) but not in group A (one gum 3 times a day) and control group (didn't receive xylitol gum). According to qualitative evaluations, xylitol use did reduce the levels of MS in mixed dentition children. It has been suggested that a daily intake of 2 tablet for 3 times a day (about 10g) is needed in order to obtain a clinical anticariogenic effect.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.1
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• pp.21-31
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• 2018

This study aimed to investigate the correlation between the inclinations of the incisors and lips in mixed dentition aged 7 - 11 years. Lateral cephalometric radiographs of 353 children were analyzed to measure the upper incisor inclination, lower incisor inclination, lower-nasolabial angle, and mentolabial angle in relation to the skeletal malocclusion classification. The measurements were then assessed using the Kruskal-Wallis test, Pearson correlation, and multiple regression analysis. There were significant negative correlations between the inclination of the upper incisors and lower-nasolabial angle in all classes of skeletal malocclusion. There was a negative correlation between the inclination of the lower incisors and mentolabial angle; however, class II malocclusion had a significant positive correlation. This study identified the factors that affect lip inclination and verified their associations.

• 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.49 no.1
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• pp.121-130
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• 2022

Molar-incisor malformation (MIM) is a newly reported dental anomaly with molar root deformity and incisor crown defects. MIM-affected teeth may cause severe pain with no apparent tooth caries. Since the affected molars clinically appear normal, radiographs are recommended for accurate diagnosis on the first visit. Since MIM-affected patients are in mixed dentition, timely and appropriate interventions are needed to avoid unnecessary pain and complicated clinical issues. This report was written to describe two patients who had MIM in early mixed dentition and report their 2-year follow-ups.

• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.145-150
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• 1984

Author have measured the depth of gingival sulcus of the primary teeth. 333 teeth were selected from the children who attended on the department of pedodontic, College of dentistry, Yonsei University, and kindergarten children at Won Ju city aged from 1 year 8 months to 10 year 2 months. 1998 point were measured. The results were as follows. ; 1. Facial surface was the shallowest in sulcus depth compared with other surfaces. It was 1.56 mm. The depth of sulcus in lingual surface was deeper than facial. 2. The deepest part of each surface was mesial and distal, There were no statistical differences between mesial and distal part of the sulcus depth. 3. The mean sulcus depth of each tooth was as follows. Primary central incisor.....1.71mm. Primary canine....1.75mm. Primary second molar.....2.03mm. 4. The mean sulcus depth of upper was 1.86mm, and the lower was 1.76mg. The upper tooth was deeper than lower in sulcus depth. 5. The lower primary central incisor had the shallowest sulcus and the upper 2nd primary molar had the deepest compared with other tooth. 6. There wasn't specific statistical differences between the age groups of primary dentition and mixed dentition.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.1
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• pp.79-89
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• 1990

The incidence and several characteristic features of fused and geminated teeth were studied radiographically, with full mouth periapical radiogram and pantomogram, in 4201 patients of mixed dentition and 5358 patients of permanent dentition. The obtained results were as follows: 1. The prevalence was revealed to 2.86%, 0.32%, 0.33%, and 0.06% in deciduous fused tooth, permanent fused tooth, deciduous geminated tooth and permanent geminated tooth respectively, and these anomalies were occured in female more than male. 2. Fused teeth were observed predominantly in lower anterior teeth area, especially in lateral incisor and canine region, and many cases of deciduous geminated tooth were observed in upper central incisor region. 3. Congenital missing rates of succedaneous tooth in deciduous fused teeth were 57.1 %, 85.7%, 71.0%, 69.0% in upper right and left central-lateral incisor regions, lower right and left lateral incisor-canine regions, respectively. 4. Prevalence of dental caries was 42.3%, 18.8% and 5.6% in deciduous fused, deciduous geminated and permanent fused tooth, respectively. 5. In classifying of fused and geminated teeth into 9 types, by following appearance such as number of crown, root, pulp chamber and pulp canal of those teeth, it was more favorable that Type Ⅰ(2 crown, 2 root, 2 pulp chamber, 2 pulp canal) in deciduous fused tooth and Type Ⅸ (I crown, 1 root, 1 pulp chamber, 1 pulp canal) in permanent fused tooth, deciduous and permanent geminated tooth.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.122-128
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• 2021

Short root anomaly (SRA) is a rare dental condition with abnormally short and blunt root morphology. It mostly affects maxillary central incisors symmetrically and only has been observed in permanent teeth. A 9-year-old girl was referred from a local dental clinic for short root development in mixed dentition with no symptoms. Radiographic and intraoral examinations revealed SRA on upper and lower incisors and mandibular first molars along with other dental anomalies such as enamel hypoplasia and dens invaginatus. During long - term follow - up for 5 years, her mixed dentition has changed to permanent dentition and generalized SRA was observed in all permanent teeth. Cephalometric radiograph also revealed the calcification between the anterior and posterior clinoid processes described as a sella turcica bridge which was reported associating with dental anomalies. Early diagnosis of SRA is emphasized for successful management and prevention of root resorption and tooth loss. This report aimed to present a rare case of generalized SRA along with other dental anomalies and sella turcica bridging in a female patient through long - term follow - up.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.7 no.1
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• pp.19-26
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• 1977

The purpose of this study was to obtain the cephalometric maxillofacial soft tissue measurements, and to define the differences that exist between males and females on the soft tissue profile who had normal occlusion in mixed dentitions. For the object of this study, cephalometric radiographs were obtained from the centric occlusion with the relaxed lip position. Copper filter was designed to obtain both hard and soft tissue structure on the same film. The subjects consist of 100 males and 100 females from 8 to 12.4 years with the normal occlusion and acceptable profiles. The author measured facial depth, vertical height from the tissue profiles in the mixed dentitions. The significant test compare males with females. The following results were obtained from the study 1. In facial convexity, much more larger females than that of males. 2. Inclination of the lip posture were more larger in maxilla (male) and in females more larger in the mandible. 3. The thickness of soft tissue were thicker in males, the height of nose were more prominent in females. 4. There were no significant differences in both sexes.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.15-25
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• 1994

Keratinized ginigva has clinical singificance in periodontal health because it plays important roles in resistance to mechanical trauma, to penetration of bacteria, and to tensional stress by muscle attachment. In order to investigate the width change of anterior keratinized gingvial during transitional period, the width of kerainized gingiva on anterior teeth was measured annually in elementary school children with deciduous dentition until the successive anterior teeth were completely erupted. The distance from the gingival margin on mid-portion of crown to mucogingival junction was measured by Boley gauge(Hu-Friedy, U.S.A.) and was recorded as the width of keratinized gingiva. The difference of the width of keratinized gingiva according to sex and dentition was analyzed statistically by Student t-test. Following results were obtained : 1. In deciduous dentition, it was shown that the width of keratinized gingiva on maxillary central incisors($3.28{\pm}0.83mm$) was the widest(p<0.01), and that on maxillary lateral incisors, mandibular central and lateral incisors was $2.69{\pm}0.86mm$, $2.51{\pm}0.71mm$, $2.43{\pm}0.68mm$, respectively. 2. In mixed dentition, it was shown that the width of keratinized gingiva on maxillary central incisors ($5.10{\pm}0.86$) was the widest(p<0.01), and that on maxillary lateral incisors, mandibular central and lateral incisors was $4.35{\pm}0.83mm$, $3.51{\pm}0.60mm$, $3.57{\pm}0.66mm$, respectively. 3. The width of anterior keratinized gingiva was significantly increased after the successive anterior teeth were completely erupted(p<0.001). The width of keratinized gingiva on maxillary central and lateral incisors, and mandibular central and lateral incisors was increased by $1.82{\pm}0.83mm$, $1.65{\pm}0.69mm$, $0.99{\pm}0.39mm$, and $1.14{\pm}0.98mm$, respectively. 4. There was no statistical significance in the difference of the width of anterior keratinized gingiva between male and female(p>0.05).