• The korean journal of orthodontics
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• v.12 no.2
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• pp.145-154
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• 1982

Plaster models were constructed and orthopantomographs were taken for 86 male and 70 female primary school pupils, whose upper and lower permanent 4 incisors and 1st molars were completely erupted without crowding; whose deciduous canines and molars were found almost uniformly even without any visible tooth fractures, dental caries or restorations on proximal surfaces of the teeth. Certain reference points on the orthophantomograph were set up and measured and the values were compared with actual or predicted values from the models. The following results were obtained: 1. In regards to available space, the values from the orthopantomograph were greater than the values from the models by a mean of 3.24% on the upper and 10.06% on the lower for males; 3.05% on the upper and 10.01% on the lower for females. 2. In regards to total mesiodistal widths of permanent canine, 1st and 2nd premolars, the values from the orthopantomograph were greater than the presumed values based on the size of lower permanent 4 incisors from the models by a mean of 18.50% on the upper and 24.09% on the lower for males; 14.54 on the upper and 20.51% on the lower for females. 3. Comparing the magnified values of total mesiodistal widths of permanent canine, 1st and 2nd premolars with those of available space, the regression constants of regression equation (Y = a + bX) between them were a=3.2336, b=0.6533 on the upper and a=5.0138, b=0.3290 on the lower for males; a=2.5994, b=0.6521 on the upper and a=3.0113, b=0.6586 on the lower for females. 4. The correlation coefficients between the magnified values of available space and permanent canine, 1st and 2nd premolars were moderately positive as 0.6474 in the upper and 0.505 on the lower for males; 0.6493 on the upper and 0.6183 on the lower for females. 5. In regards to magnified values of the available space from the orthopantomographs there were no significant difference between sexes, (P>0.05) but of the total mesiodistal widths of permanent canine, 1st and 2nd premolars, a significant difference between sexes was found.(p<0.01).

• Journal of Korean society of Dental Hygiene
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• v.9 no.2
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• pp.165-178
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• 2009

The purpose of this study was to provide basic information for improving oral health and dental hygiene through comprehensive dental hygiene care. The subjects in this study were 54 patients who had been treated for 4 weeks in clinic of the Dental Hygiene Department of G University under comprehensive dental hygiene control and care and measured their oral condition, intensity of oral malodor, Simplified Oral Hygiene Index (S-OHI), and Modified Personal Hygiene Performance Index (PHP-M), and surveyed their oral health behavior and oral health consciousness. The results of the study were as follows: 1. The intensity of malodor decreased by 16.49ppb from 75.33ppb on the first visit to 50.84ppb on the last visit when the comprehensive dental hygiene care had been finished. 2. As to change in S-OHI according to gender between the first visit and the last visit for comprehensive dental hygiene care, S-OHI decreased from 2.89 on the first visit to 1.16 on the last visit, and the difference was statistically highly significant. 3. As to change in PHP-M index by tooth according to gender and age between the first visit and the last visit, PHP-M index of the first 6 teeth decreased very significantly from 0.50 on the first visit to 0.34 on the last visit. 4. As a whole, significant improvement was observed in every tooth. According to gender and age, PHP-M index for Tooth No. 26, 36 and 32 decreased significantly in men and women, and those aged under 30 and those aged 30 or over, but for Tooth No. 13 and 15 and 44 it decreased significantly only in men and those aged 30 or over, and for Tooth No. 44 only in men. As presented above, the oral health behavior and oral health consciousness of the visitors to the oral prophylaxis practice room are very important, and it is necessary to enhance their interest in and knowledge of how to improve oral health. Furthermore, comprehensive dental hygiene care required for improving the visitors' oral health.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.3
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• pp.342-347
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• 2009

Statement of problem: when using resin for class II restoration, micoleakage by instrumentation can be regarded as the primary negative characteristic. A review of the available literature suggests that using flowable resin as liner to decreased microleakage. Purpose: The aim of this study was to determine the influence of the nanofilled flowable resin lining on marginal microleakage after load cycling in class II composite restoration fillings using nanofiller resin. Material and methods: 24 extracted premolars were prepared with class II cavity. F group was restored the nanofilled resin with the nanofilled flowable resin as liner. NF group was restored the nanofilled resin only. After restoration, an experiment was performed on 2 groups using a 300N load at 104, 105 and 106 cycles. Prior to and before each load cycling, it was gauged length on total marginal microleakage, axial marginal microleakage and buccal, gingival, lingual marginal microleakage. Data were analyzed with the Mann-Whitney test & Kruskal-Wallis test. Results: There were statistically significant differences between 2 groups and between individual groups. (P <.05) The result showed less microleakage in teeth restored by the nanofilled resin, which was lined by the nanofilled flowable resin. Conclusion: There was significant reduction in microleakage when the nanofilled flowable resin lining was placed underneath the nanofilled resin in class II composite restoration fillings.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.270-277
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• 2002

Since founded in 1959, it's well known that the KAPD has pioneered in the researches and clinical aspects of pediatric dentistry in Korea. It's official journal, the Journal of the KAPD, was first published in 1974 and has pressed total 956 articles up to now(March, 2001). In this study, all the articles pressed in this journal have been surveyed, focussing in their main theme, their chronological and thematic distribution. The thematic classification was made with the reference of the previous studies and renowned textbooks in pediatric dentistry. And we obtained the results as follows: 1. The researches on dental materials and dental equipments have shown continuous increase throughout the period. 2. The researches on dental caries, caries prevention and systemic disorders have occupied relatively high proportion consistently. 3. The researches on malocclusions and cysts/minor surgery have shown increasing tendency in the second period, but are decreasing in the third period. 4. The researches on craniofacial growth/development, tooth development/eruption, developmental disorders of teeth, management of eruption space have shown decreasing tendency. 5. The researches on behavioral research, oral habits, occlusion of primary-mixed dentition have shown very low proportion, reaching no more than 1% throughout the period.

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.2
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• pp.172-179
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• 2015

The developmental mechanism of root formation is a complex process. Hereditary and environmental factors may affect the morphology of the developing root. A total of 12 cases was presented with permanent first molars with abberant root morphology. Clinically, these teeth appeared as a normal crown. However, radiographically, the root was slender, twisted and characterized by irregular lengths. In addition, root trunk length was shorter and pulp chamber was obliterated. In these cases, periapical radiolucency and loss of lamina dura were often observed. In 6 cases, an abnormal root of the primary second molars were also present, as well as root malformation of permanent first molars. In 3 cases, permanent central incisors also had a dysmorphic crown. These cases almost all had medical history, such as premature birth, brain infection or congenital heart disease in infants. The present paper describes cases of permanent first molars with an abnormal root that are rarely reported in literature. This case may intensify the variation in the permanent first molar and is intended to reinforce the clinician's awareness of rare morphology of the roots.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.69-75
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• 2002

A number of techniques may be employed to reduce the discomfort of syringe or needle for dental care. The use of topical anesthesia is one such method. Topical anesthetics are applied to alleviate pain during many clinical procedures, such as injection of local infiltration anesthetics, primary tooth extraction, X-ray taking of sensitive patients, reducing gag reflex prior to impression taking. In children, placement of a rubber dam clamp, however, may cause significant discomfort for purpose of pit and fissure sealant and preventive resin restoration(PRR). A topical anesthetic would be beneficial to aid in rubber dam placement for this purpose. It has been suggested that all intra-oral topical anesthetics are equally effective on reflected mucosa, however EMLA(an acronym for eutectic mixture of local anesthetics), which was developed in the 1980s and produces surface anesthesia of skin, has been shown to be more effective than conventional topical anesthetics when used on attached gingivae. This report is topical anesthesized 4 case by EMLA cream, who showed better effect in reducing the pain of infiltration anesthesia, extraction of deciduous teeth, rubber dam clamp placement and reducing the pain of preformed crown adaptation.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.12 no.2
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• pp.82-86
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• 2016

Lowe syndrome is X-linked gene disorder, characterized by cataracts, renal dysfunction and brain abnormalities. Oral healthcare of young patients with Lowe syndrome could be easily neglected due to the uncooperative behavior or other systemic condition of the child. We are presenting a case of successful treatment under general anesthesia with uncooperative child with Lowe syndrome. A 3-year old boy with Lowe syndrome visited Seoul National University Dental Hospital for multiple caries. He had been suffering from congenital cataract, medullary nephrocalcinosis and hypotonia. Multiple caries were observed from clinical and radiographic examination. Concerning behavior management problem and possibility of aspiration due to hypotonia, dental treatment under general anesthesia was planned. Left upper primary first molar was extracted to prevent further infection. Other teeth were treated with Stainless steel crown or composite resin restoration based upon the extent and the severity of dental caries. Under general anesthesia, dental procedure was carried out successfully and safely. Considering uncooperative behavior and other medical conditions of the patient, general anesthesia could be effective. Home oral care and periodic visit to dental clinic should be emphasized to the caregiver of patient with Lowe syndrome, considering the susceptibility of dental caries and other oral manifestation.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.694-699
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• 2001

The prognosis for class III patients in growing child can be made in mixed dentition and the severity of the symptom is often amenable to early intervention. Class III malocclusion can be classified as functional class lit and skeletal origin. Skeletal Class III malocclusion is usually characterized by overdeveloped mandible, underdeveloped maxilla, but the cause of pseudo class III is most dentoalveolar or functional shift of mandible. The primary goal of early intervention of malocclusion is to supply an environment that is conducive to the development of favorable occlusal relationships and avoiding of worsening of the problems. Inverted labial bow appliance is introduced as an appliance to combine the advantage of active plate and activator. It is undemanding with this appliance to initiate not only dentoalveolar expansion of upper dentition but also to orient the functional retrusion of mandible. With simple design the compliance for patients such as mouth breathing problem can be improved. For successful use of this appliance it is utmost important to make accurate and early diagnosis between pseudo- and skeletal class III malocclusion. This article will demonstrate the use of an Inverted labial bow appliance for early treatment of a functional Class III malocclusion. After 4 month treatment, anterior crossbite was treated and the results were achieved mainly dentoalveolar change of upper and lower anterior teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.701-704
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• 2004

In this case, we would like to discuss about the single rooted deciduous mandibular first molar. The deciduous mandibular molar of a five years old boy was shown to have a single root, bilaterally. Ordinarily, the maxilary molars have three roots and the mandibular molars have two roots. However, when the hertwig's epithelial root sheath do not invaginate properly during tooth development, root fusion can occur from the absence of root separation. Molars with fused roots not only have unfavorable crown to root ratio, but also according to many reports, have higher probability of having multiple congenitally missing teeth or dens invaginatus in the maxillary incisors, consequently requiring preventive dental treatment In addition, disorders such as ectodermal dysplasia, syndactyly, clinodactyly, bluish sclera can also be related to this condition. Root fusion is known to be of autosomal recessive inheritance. Up to date, single rooted molars have been reported several times in permanent dentitions but hardly in deciduous dentition, which is the motive for this paper.

• Applied Microscopy
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• v.34 no.2
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• pp.145-157
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• 2004

The aim of the present study was to examine in detail, both at light and electron microscopical levels, the morphological variations in ameloblast of the fetal rat incisor enamel organ. Rats were started on distilled water at the beginning of pregnancy. The pups were sacrificed 11 days after delivery and animals were perfused intravascularly with glutaraldehyde and the incisors were removed. To examine on the ultrastructure of the ameloblast, the study employed primary light microscopy but electron microscopy was used to clarify some of the light microscopic finding. Longitudinal sections through the incisors of the rat show a continuous layer of ameloblasts on the labial surface of the tooth. This layer contains the entire sequence of developmental stages in enamel production. The ameloblast layer was divided into three main zones: 1) Presecretory zone, region of ameloblasts facing pulp. 2) Secretory zone, region of inner and outer enamel secretion. 3) Maturation zone, region of reduced ameloblasts. In particularly, the present study has shown that two distinctively different types of ameloblasts appear in the enamel organ during enamel maturation in the rat incisor. These two types have been designated ruffle-ended ameloblasts (rAB) and smooth-ended ameloblasts (sAB). The fluoride produces marked alteration in the fine structure of ameloblast from teeth of young rats, such as large confluent distensions of the endoplasmic reticulum and swelling of isolated mitochondria. This experimental data suggested that exposure prolonged of animal to high level of fluoride appears to induce a few dramatic changes in the normal appositional growth and initial mineralization of enamel created during amelogenesis.