• Journal of Technologic Dentistry
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• v.15 no.1
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• pp.89-94
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• 1993

The tooth size and shape of the permanent incisor teeth have been studied and analyzed about the mean size, S.D, S.E, etcs and percentage from stone model of 100 Korean male and 74 Korean female. The results were as follows. 1. The crown length of permanent incisor teeth were longer in males than in females statistical differences of males and female were not found. 2. the mesio-distal diameters of permanent incisor teeth were larger in males than in females and statistical differences of males and females were found in mandibular lateral incisor and the bigest were max. central incisor, 2nd max. lateral incisor, 3rd man. lateral incisor and the smallest were man. central incisor. 3. The square form in max. central incisor was the greatest percentage and the tapering form in max. lateral incisor and man, incisor was the greatest percentage but tapering form and ovoid form and other shape were found in max. lateral at the same ratio. 4. Concerning the labial developmental groove "midium" was the greatest percentage in the max. central incisor and "low" was the greatest percentage in the man incisor. Concerning the incisal line, straight line was the greatest percentage in the max, incisor and man, incisor and concerning the lingual tubercle "none" was the greatest percentage in the max. incisor. 5. In comparison between left side and right side of incisor, the ratio of same shape ware 22.4%-36.2% but similar or dissimilar cases were more frequently found.

• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.25-39
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• 1984

The author has sought to determine the time and the sequence of permanent teeth eruption in Korean children. The study group consisted of 15,671 healthy children (male 8,015 ; female 7,656) aged 5-13 years old who lived in Seoul or Cheongju. The results were as follows : 1. The eruption times of permanent teeth were 0.45 years earlier in females than in males. 2. The ages corresponding to $ER_{50}$ of permanent teeth were as follows : In Maxilla 1) central incisor was 7.37 yrs 2) lateral incisor was 8.50 yrs 3) canine was 10.83 yrs 4) 1st premolar was 10.30 yrs 5) 2nd premolar was 11.09 yrs 6) 1st molar was 6.49 yrs 7) 2nd molar was 12.79 yrs In Mandible 1) central incisor was 6.40 yrs 2) lateral incisor was 7.41 yrs 3) canine was 10.18 yrs 4) 1st premolar was 10.26 yrs 5) 2nd premolar was 11.15 yrs 6) 1st molar was 6.32 yrs 7) 2nd molar was 12.05 yrs 3. The eruption sequence of permanent teeth by Z-test was as follow: In Male 1st : Mandibular 1st molar, and Mandibular central incisor 2nd : Maxillary 1st molar 3rd : Maxillary central incisor 4th : Mandibular lateral incisor 5th : Maxillary lateral incisor 6th : Mandibular canine, Maxillary and Mandibular 1st premolar 7th : Maxillary canine 8th : Maxillary and Mandibular 2nd premolar 9th : Mandibular 2nd molar 10th : Maxillary 2nd molar In Female 1st : Mandibular 1st molar, and Mandibular central incisor 2nd : Maxillary 1st molar 3rd : Mandibular lateral incisor, Maxillary central incisor 4th : Maxillary lateral incisor 5th : Mandibular canine, Maxillary and Mandibular 1st premolar 6th : Maxillary canine 7th : Maxillary and Mandibular 2nd premolar 8th : Mandibular 2nd molar 9th : Maxillary 2nd molar 4. The corresponding permanent teeth in the mandible generally erupted earlier than the corresponding permanent teeth in the maxilla by an average of 0.73 years, but the mean eruption time of mandibular 1st premolars was almost the same as those of maxillary 1st premolars, and the mean eruption time of mandibular 2nd premolars was 0.06 years later than those of maxillary 2nd premolars. 5. There is no significant difference between left and right arch in the eruption time and sequence. 6. Generally, the ages of permanent teeth eruption tended to be earlier than those of Dr. Cha's data from 1963.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.475-483
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• 1997

Fracture of the crown in a permanent incisor is relatively common. When it occurs with pulp exposure, it presents both restorative and endodontic problems. In the restoration of a fractured incisor, reattachment of the original fragment or restoration with a composite resin is preferred over a temporary crown. If fractured fragment is intact, the tooth can be restored with reattachment of the fragment. An exposed pulp in a young crown-fractured incisor is usually treated with either pulp capping or pulpotomy depending on the size of an exposure and time elapsed since injury. However, in teeth showing vital and/or hyperplastic pulp tissue at the exposure, only superficial layers of the pulp and surrounding dentin should be removed : i.e. partial pulpotomy can be performed in immature as well as mature teeth. This paper reports 2 cases of crown-fractured permanent incisors with pulp exposure that had been treated by reattachment of original fragment followed by partial pulpotomy or partial pulpectomy. The following results are obtained. ; 1. Fragment reattachment is an acceptable semi-permanent restoration of crown fractured young permanent incisor. 2. Partial pulpotomy is recommended as the treatment of choice in crown-fractured permanent teeth with pulp exposure.

• 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.

• The Journal of the Korean dental association
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• v.42 no.2 s.417
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• pp.150-157
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• 2004

Inverted maxillary incisor is that maxillary incisor rotates counterclockwise direction. The cause of this 'Inverted incisor' is the injury of the deciduous predecessor transmitted to the developing permanent tooth germ or displacement of permanent tooth crown portion from unknown origin. Dilaceration, defined as a distorted root from, may result from mechanical injury during eruption period or ectopic development of tooth germ. This article presents a case of an inverted and dilacerated maxillary right central incisor. Through orthodontic traction, the dilacerated and inverted incisor was successfully moved into the proper position.

• Journal of Oral Medicine and Pain
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• v.4 no.1
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• pp.22-30
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• 1979

In order to evaluate the normal eruption time of Korean permanent teeth, the uthor had examined the eruption phases of permanent central incisors in 714 malw and 581 female children aged from 4.5 to 9-year old and analysed. The eruption was divided into 3 phases; the tip of crown can be seen, the half of the crown can be easily seen, and full length of the crown can be seen. The obtained results were as follows : 1. It seemed that percentage of the erupting and erupted permanent central incisor in female by age was higher than that of male. 2. In general, percentage of the erupting and erupted lower central incisor by age was higher than that of upper first molar.

• The Journal of the Korean dental association
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• v.57 no.11
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• pp.679-688
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• 2019

A 8-year-old patient presented with a crown-root fracture of the maxillary right central incisor with an oblique subgingival fracture line. A multidisciplinary treatment approach including endodontic treatment, surgical extraction and intraalveolar repositioning was used to gain sufficient crown length of the fractured maxillary incisor. The coronally repositioned maxillary right central incisor was stabilized by a resin wire splint. Apexification using MTA was performed. Resin core and direct resin restoration(Cl IV) on fractured teeth was built up. Clinical and radiographic follow-up of the maxillary right central incisor after 36 months showed no signs of root resorption or pathology and acceptable aesthetics and functions were maintained. Surgical extrusion can be considered as a good treatment modality for young patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.7 no.1
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• pp.21-32
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• 1980

The purpose of this study is to determine the developmental relationship between the maxillary primary central incisors and their permanent successor. The auther took 315 cases of lateral cephalogram of the children (males were 171, females were 141) Angular change of the teeth and horizontal and vertical linear change were observed. The obtained results were as follows: 1. The inclination of the long axes of both incisor teeth was relatively stable and labio-version of both incisore was significant at 7 years of age. 2. The distance between the incisal edge of the permanent central insisor and the resorbing apex of the primary maxillary central incisor remained within 2mm of each other, 3. Vertical growth of the maxillary anterior portion was greater than horizontal growth from 6 to 7 years of age. 4. There was not a significant sexual difference.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.693-702
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• 2005

Accurate timing and sequence of eruption of permanent teeth are indicies of growth and essential for pediatric dentistry and pediatric clinical orthodontics. From the children brought to the Yonsei Dental Hospital during 2001 to 2003, 654 boys and 542 girls, ranging in age from five to fourteen years, were selected and analysed. The following was concluded. 1. Eruption time of maxillary teeth is 6.81 years in boys, 6.78 years in girls for central incisor, 8.30 years in boys, 7.98 years in girls for lateral incisor, 10.28 years in boys, 10.04 years in girls for canine, 9.74 years in boys, 9.90 years in girls for first premolar, 10.87 years in boys, 10.41 years in girls for second premolar, 6.25 years in boys, 6.54 years in girls for first permanent molar, 12.21 years in boys, 12.03 years in girls for second permanent molar 2. Eruption time of mandibular teeth is 6.00 years in boys, 6.06 years in girls for central incisor, 6.99 years in boys, 6.74 years in girls for lateral incisor, 9.83 years in boys, 9.17 years in girls for canine, 9.92 years in boys, 9.75 years in girls for first premolar, 10.66 years in boys, 10.39 years in girls for second premolar, 5.99 years in boys, 5.75 years in girls for first permanent molar, 11.92 years in boys, 12.17 years in girls or second permanent molar. 3. The following eruption sequence was observed 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 maxilla. The first permanent molar erupted first, followed by the central incisor, the lateral incisor, the canine, the first premolar, the second premolar and the second permanent molar in the mandible.

• The Journal of the Korean dental association
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• v.11 no.12
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• pp.787-799
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• 1973

Surveying the calcification degree of permanent tooth crown in 719 Korean children (Male 387, female 332) from 2 to 10 years old by orthopantomograph, the author got the following results. 1. Female was earlier than male in calcification of permanent teeth. 2. The results of the complete calcification of the permanent tooth crown were as follows. 3. The completion of calcification in the mandibular crown was seen earlier than that of the maxilla. 4. The order of calcification in permanent tooth crowns was as follows : 1 st molar, central incisor, lateral incisor, canine, 1st premolar, 2nd premolar, and 2nd molar. 5. The completion of calcification of the permanent crowns in Korean children was slightly retarded comparing with the Japanese and the American children.