• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.3
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• pp.185-193
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• 2013

Mineral trioxide aggregate (MTA) has recently been used as a pulpotomy medicament for primary molars. The aim of this study was to evaluate and compare the proliferation and differentiation potential of dental pulp stromal cells of permanent teeth and deciduous teeth cultured on MTA-coated surface. Human dental pulp stromal cells were obtained from human permanent premolars and deciduous teeth and cultured on MTA-coated culture plates. The cells were subjected to proliferation assay and cell cycle analysis. Their differentiation potential was evaluated by analysing changes in the mRNA expressions of runt-related transcriptional factor 2 (Runx2) and alkaline phosphatase (ALP). Morphological changes of cells in direct contact with MTA were observed using scanning electron microscopy (SEM). The proliferation rates, distribution of cell cycles and mRNA expression patterns of Runx2 and ALP were similar in both types of pulpal cells. SEM observations revealed that both types changed into more dendrite-like cells. On the surface of MTA, human dental pulp stromal cells from deciduous and permanent teeth were able to both proliferate and differentiate into cells that induce mineralization. MTA is suitable as a biocompatible pulpotomy medicament for primary teeth.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.1
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• pp.81-87
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• 2019

Patients with Down's syndrome have several dental complications such as small teeth caused by underdevelopment of dentin and enamel, periodontitis, agenesis of teeth, prolonged retention of primary teeth and malocclusion due to narrow palate. Removable denture with maxillary double crowns would be a good treatment option to solve the problems of the patient with Down's syndrome. Double crowns compensate the insufficient support and retention of denture and easily solve the cross bite problem. Double crowns also allow easy repair of denture in case of abutment teeth extraction. In this case, 26-year-old female patient with Down's syndrome and dental phobia had small number of teeth with enamel hypoplasia, prolonged retention of primary teeth and dental cross bite. Prosthetic treatment was done using removable denture with double crowns in the maxilla. In the mandible, teeth preparation was done on enamel margin without anesthesia. Anterior laminate and posterior complete zirconia crown restorations were performed. As a result, the cross bite was effectively corrected by denture with double crowns. Pronunciation and appearance were also improved without extraction of teeth and dental anesthesia.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.232-239
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• 1999

Exfoliation of the primary teeth and eruption of the permanent teeth is a normal and predictable physiologic process. The accurate prediction of tooth development is of major importance in treatment planning for children. Norms that correspond to the child's age and development have been determined by many investigators. However, there are a variety of factors that may hasten, retard, or otherwise affect the normal developmental process. Among the factors that influence tooth eruption is the premature loss of primary teeth. An abscess of a primary molar, followed by bone resorption and early extraction or exfoliation may lead to premature eruprion of the permanent succesor, and a variety of clinical sequelae. I, hereby present the patients who have prematurely erupted permanent successor in Seoul National University Hospital Pediatric Dentistry, and report the clinical and radiologic characteristics, its sequelae, proper managements, and followed up findings.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.1
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• pp.12-19
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• 2009

The aim of this study is to assess the antibiotic activity of Actinomyces in plaque from black stained primary teeth to Streptococcus mutans. Samples were obtained from four children, 2-6 years of age, who had black stains on all erupted primary teeth. 16 different Actinomyces spp. were isolated, and antibiotic activity test with paper disc method was done. The results were as follows, 1. No.1 and No.5 Actinomyces spp. showed the antibiotic activity to Streptococcus mutans and the activity of No.5 Actinomyces spp. could compete with that of Oxacillin. 2. No.1 and No.5 Actinomyces spp. also exhibited the antibiotic activity to Bacillus cereus, Bacillus subtilis commonly used as experimental bacteria for testing antibiotic activity. 3. For identification of No.1 and No.5 spp., PCR analysis was done. No.5 spp. matched Actinomyces viscosus at 97% level but No.1 spp. didn't match.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.1
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• pp.126-131
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• 2005

The purpose of this study was to observe the potentiality of a mixture of antibiotics to relieve the endodontic and periapical infections in primary teeth. A mixture of metronidazole, ciprofloxacin, and minocyclin in distilled water or in a root canal sealer were used to disinfect the infected endodontic and periapical lesions. For application of this mixture, medication cavities were prepared at orifices of root canals by using the $Fissurotomy^{(R)}$ burs(S S White, USA). The cavities and bottom of pulp chamber were filled with antibiotics mixture. In this cases, clinical symptoms were improved following a single application of that mixture. Gingival swelling, pain, and fistulae were disappeared within a week. More long term evaluation will be needed. Although there were no reports of side effects, care should be taken if children are sensitive to antibiotics. Within the limitations of this case, the mixture of 3 antibiotics provided an excellent improvement in treatment of infected primary teeth under the physiologic root resorption.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.277-292
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• 2020

The pulp treatment of primary and immature teeth in the children and adolescents is affected by the environment of the patients, clinical careers and dentists performing the techniques, as well as clinical modalities and pulpal diagnosis. The purpose of this study was to investigate the current status of pulp treatment performed in real clinical practice, as well as the reasons behind the choice of treatment methods. The study was conducted on a total of 153 members of the Korean Academy of Pediatric Dentistry, and statistical data from the Health Insurance Review and Assessment Service (HIRA) from 2010 to 2018 were analyzed together. Both the survey results and the statistics from the HIRA showed that 1-visit pulpectomies of primary teeth were most common, and the frequency of the use of the Ni-Ti file was increased in children with primary or mixed-dentition. In the treatment of immature permanent teeth, regenerative endodontic treatment by individual dentists was found to be less frequent than in university hospitals.

• Molecules and Cells
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• v.37 no.7
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• pp.562-567
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• 2014

Human Hertwig's epithelial root sheath/epithelial rests of Malassez (HERS/ERM) cells are epithelial remnants of teeth residing in the periodontium. Although the functional roles of HERS/ERM cells have yet to be elucidated, they are a unique epithelial cell population in adult teeth and are reported to have stem cell characteristics. Therefore, HERS/ERM cells might play a role as an epithelial component for the repair or regeneration of dental hard tissues; however, they are very rare population in periodontium and the primary isolation of them is considered to be difficult. To overcome these problems, we immortalized primary HERS/ERM cells isolated from human periodontium using SV40 large T antigen (SV40 LT) and performed a characterization of the immortalized cell line. Primary HERS/ERM cells could not be maintained for more than 6 passages; however, immortalized HERS/ERM cells were maintained for more than 20 passages. There were no differences in the morphological and immunophenotypic characteristics of HERS/ERM cells and immortalized HERS/ERM cells. The expression of epithelial stem cell and embryonic stem cell markers was maintained in immortalized HERS/ERM cells. Moreover, immortalized HERS/ERM cells could acquire mesenchymal phenotypes through the epithelial-mesenchymal transition via TGF-${\beta}1$. In conclusion, we established an immortalized human HERS/ERM cell line with SV40 LT and expect this cell line to contribute to the understanding of the functional roles of HERS/ERM cells and the tissue engineering of teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.4
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• pp.514-520
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• 2018

Congenital absence of the primary canines is very rare. Congenital absence of primary teeth often causes their successors to not develop at all or affects the eruption of their successors. The purpose of this paper was to report the cases of 2 children with early eruption of the maxillary permanent canines at ages 4 and 6 years, respectively, following congenital absence of their maxillary primary canines, which are not common in earlier studies. Although tooth eruption and shedding exhibit some physiological variation, certain clinical cases are extreme. Premature eruption of the maxillary permanent canines may cause complications in terms of the space available for the eruption of adjacent teeth. Additionally, early eruption of permanent teeth increases the need for more careful oral hygiene. Therefore, the pediatric dentist must be alert to such rare cases.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.19-26
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• 1997

Odontodysplasia is a rare developmental anomaly of tooth formation in which hard tissue are affected. Odontodyplasia affects the primary and permanent dentitions in the maxilla, mandible, or both jaws. The maxilla is involved twice as often as the mandible. The condition is more common in female than in male patients and in the anterior than in the posterior regions. The clinical manifestation of odontodysplasia are hypoplasia and hypocalcification of the enamel and dentin of affected teeth. Teeth tend to be small and discolored, with short roots and widely open pulp canal. Delayed eruption of affected teeth with abscess formation is common. Radiographically teeth assume a faint radiolucent image ("ghost teeth"). enamel and dentin appear thin and are similar in radiodensity. The pulp chambers are often larger than normal, calcifications(pulp stone and denticle) are found within them. The etiology of regional odontodysplasia is unknown. However, several causes have been discussed, including somatic mutation, local circulatory disorders, local trauma, failure of migration and differentiation of neural crest cells, local infection.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.1
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• pp.78-83
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• 2009

In case of endodontic treatment and extensive restoration of severe dental caries, trauma, and developmental defect, esthetic restoration of primary incisors and permanent anterior teeth for children and adolescents period is delicate matter for pediatric dentists. Existing restorative methods for anterior teeth have retentive and esthetic limitations for badly damaged teeth, especially for the adolescent anterior teeth. Therefore, the preparative stage for setting the permanent prosthesis as well as the retention and esthetics have to be considered. In this case, esthetic restoration for badly destroyed anterior teeth was tried with fiber-reinforced post and the result was satisfactory.