• Journal of Technologic Dentistry
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• v.13 no.1
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• pp.21-26
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• 1991

The mesiodistal crown diameters and crown length of the permanent anterior teeth have been studied and analyzed about the mean size, S.D, S.E etcs from stone models of 100 Korean male and 74 female. From the study, the following conclusions were made : 1. Statistical differences of left and right teeth were not found in the mesio distal crown diameters and crown length of the permanent anterior teeth. 2. The mean values of mesiodistal crown diameters of permanent anterior teeth were slightly larger in male than in females and statistical differences of males and females were found in maxillary right central incisor, mandibular left canine, mandibular right lateral incisor and mandibular right canine. 3. The mean values of crown length of permanent anterior teeth were slightly larger in male than in female and statistical differences of males and females were found in mandibular left canine, mandibular right canine. 4. Mesiodistal crown diameters and crown length of maxillary left lateral incisors and right lateral incisors of female are larger than that of male.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.15 no.1
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• pp.51-57
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• 1985

The purpose of this study is to investigate possible correlation between the dental anomalies and site of cleft in cleft lip and palate. In this study, 142 patients who had cleft lip and/or cleft palate were examined. The results are as follows. 1. The incidence of missing tooth was high in the permanent dentition as compared to the incidence in the deciduous dentition. 2. There was not much difference of incidence of supernumerary tooth between deciduous and permanent dentition in the group of patients who had cleft lip and jaw with or without cleft palate. 3. In the group of patients who had cleft lip and jaw with or without cleft palate, the frequency of incidence of cleft sides was higer in unilateral than bilateral cases. And, incidence of left sides was higher than right sides. 4. The type of cleft between central incisor and canine with missing lateral incisor was most frequent in permanent dentition and the type of cleft between central and lateral incisor was most frequent in deciduous dentition. 5. The type of cleft associated with tooth position in deciduous dentition was not almost the same in the succeeding permanent dentition.

• 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 the korean academy of Pediatric Dentistry
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• v.44 no.3
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• pp.263-271
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• 2017

The objectives of this study were to classify the first permanent molars showing molar-incisor hypomineralization (MIH) on the basis of defect size and to assess differences in the prognoses of restorations performed with different materials. The first permanent molars with MIH and posteruptive breakdown were categorized into MIH class I, II, and III. After performing restorations, retreatment frequencies were examined according to the defect class and initial restorative material used. Sealants, composite resins, and stainless steel crowns showed the highest survival rates in cases of MIH class I, II, and III defects, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.3
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• pp.370-377
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• 2017

Molar-incisor malformation (MIM) is a recently described dental anomaly characterized by root malformation in permanent first molars accompanied sometimes by abnormal root forms in primary second molars or enamel defects in maxillary central incisors. This report presents three cases of MIM along with a review of previous studies. Three patients exhibited abnormal root forms in the permanent first molars, with varying degrees of deformation. Two of the patients experienced medical events at birth. One of the patients was a monozygotic twin, whose twin sister exhibited normal dentition without any significant abnormalities. The present report also reviews recently reported cases of MIM in literature. In the management of MIM-associated clinical issues, consideration of microscopic features and accompanying characteristics might facilitate early diagnosis and comprehensive treatment planning.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.337-343
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• 2020

Molar-incisor malformation (MIM) is a new type of root anomaly reported recently. The characteristics of MIM are dysplastic root formations, constriction of pulp chambers and presence of calcified matrices at the level of cementoenamel junction in permanent first molars and primary second molars. In some cases, permanent maxillary incisors are also affected. The permanent first molars of the patient in this case report were affected with MIM. Generalized pulp stones were observed in overall primary dentition. Micro-computed tomography (micro-CT) imaging and scanning electron microscope-energy dispersive X-ray spectrometer analysis were performed on the extracted mandibular first molar and maxillary primary second molar of the patient. Micro-CT images revealed the discontinuity of enamel directly connected to an accessory canal of the root.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.179-185
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• 2010

Molar Incisor Hypomineralization(MIH) have recently gained intensive research interests and various clinical trials. Most prevalence, etiology, treatment studies in MIH were carried out in the European countries, and data from the Korean were seldom. This study aimed to investigate the prevalence of MIH and the status of dental caries and treatment on the first permanent molars in primary school children. For this study, 1,344 primary school students in Busan and Ulsan cities were examined directly the permanent incisors and first molars. The results of the survey were as follows: 81 MIH cases were identified among 1,344 cases. The prevalence of MIH in this group of children was 6.0%. Children with MIH showed a significantly higher DMFT value for permanent teeth than children without MIH. The mean number of decayed, missed, and filled in 1st permanent molars(DMFT index) was 1.17. The rate of children with restoration on 1st permanent molar was 13.6% and the sequence of restoration materials was as follows : composite resin, amalgam, gold inlay.

• Imaging Science in Dentistry
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• v.43 no.3
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• pp.209-213
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• 2013

It has been a challenge to establish the accurate diagnosis of developmental tooth anomalies based on periapical radiographs. Recently, three-dimensional imaging by cone beam computed tomography has provided useful information to investigate the complex anatomy of and establish the proper management for tooth anomalies. The most severe variant of dens invaginatus, known as dilated odontome, is a rare occurrence, and the cone beam computed tomographic findings of this anomaly have never been reported for an erupted permanent maxillary central incisor. The occurrence of talon cusp occurring along with dens invaginatus is also unusual. The aim of this report was to show the importance of cone beam computed tomography in contributing to the accurate diagnosis and evaluation of the complex anatomy of this rare anomaly.

• The Journal of the Korean dental association
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• v.58 no.7
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• pp.398-403
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• 2020

Odontogenic anomalies can occur as a result of conjoining defects. These include fusion, gemination and concrescence. The presence of fused teeth can lead to various clinical problems, including the aplasia of permanent successor, the supernumerary teeth and delayed eruption of permanent teeth. In general, the supernumerary teeth associated with fusion is mainly found in the maxillary anterior region. This report describes rare cases of supernumerary tooth associated with fused teeth of mandibular primary lateral incisor and canine. In the first case, fused teeth was extracted. The supernumerary teeth was erupted at canine space. The second case is still being observed. Extraction of fused teeth and observation of supernumerary teeth is planned.

• The Journal of the Korean dental association
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• v.11 no.5
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• pp.313-316
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• 1973

970 children visited attached hospital, S.N.U, were taken orthopantomograph. Of those children, there were 14 patients who have primary fused teeth. The author observed those cases and got following results. 1) Incidence of primary fused teeth was higher in female. 2) In the order of frequency, fused teeth of mandibular right primary lateral incisor and canine were 9 and that of mandibular left primary lateral incisor and canine were 4, and there was only one case in maxillary. 3) 13 cases showed the congenital absence of lateral incisor of the corresponding permanent teeth. 4) Incidence of fused teeth was 1.44%.