• The Journal of Korean Academy of Prosthodontics
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• v.46 no.6
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• pp.553-560
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• 2008

STATEMENT OF PROBLEM: Proximal contact plays an important role in the stability and maintenance of the integrity of the dental arches. However, it is difficult to evaluate quantitatively the tightness of proximal tooth contact (TPTC). PURPOSE: The aim of this study was to measure the TPTC in permanent dentition. MATERIAL AND METHODS: Ten young adult volunteers with healthy dentition participated in this experiment. The TPTC between the teeth of both the maxilla and the mandible was measured at rest state by a novel device which records the TPTC by pulling of a stainless steel strip (0.03 mm thick) using the electric motor. One-way ANOVA test was used to compare the values in all measured area. When a statistically significant difference was calculated, Bonferroni correction was applied. Independent samples t-test was used to compare the values in male and female. RESULTS: The lowest TPTC and the highest TPTC was measured between the lower central incisors (0.87 ${\pm}$ 0.20 N), and between the lower left first molar and second molar (1.99 ${\pm}$ 0.68 N), respectively. All TPTC per quadrant demonstrated a similar pattern of a continuous increased gradient in an anterior-posterior direction. There are no significant difference between the maxilla and mandible. CONCLUSION: The TPTC was measured quantitatively by a novel device and decreased progressively in a posterior-anterior direction.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.548-555
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• 2008

Dentigerous cyst is the most common type of odontogenic cyst followed by radicular cyst. Most of dentigerous cysts originate from the permanent dentition and a few of them are associated with mesiodens. The complications of a dentigerous cyst associated with mesiodens are eruption abnomalies of adjacent teeth, root resorption, displacement, rotation, diastema and the secondary infection of the cyst due to adjacent teeth. The treatment of a dentigerous cyst of a maxillary mesiodens is to enucleate a cyst with a mesiodens. Otherwise, when it is close to adjacent teeth, a cyst is to reduce the through marsupialization after removing a mesiodens. There are numerous studies on dentigerous cysts and mesiodentes alone; however, the studies on the association of the two are rare. These are case reports about patients with mixed dentition whose dentigerous cyst of a maxillary mesiodens had been removed. After removal, the patients have been regularly checked up and shown satisfactory progress.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.586-591
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• 2002

Bruxism can be generally regarded as a diurnal clenching or nocturnal teeth grinding or a combination of both. Clenching of the teeth is forceful closure of the opposing dentition in a static relationship of the mandible to the maxilla, whereas grinding of the dentition is forceful closure of the opposing dentition in a dynamic maxillo-mandibular relationship as the mandibular arch moves through various excursive positions. The causes of bruxism are not yet discovered clearly, but most consistently mentioned cause is psychological stress. Bruxism can be also associated with sleep disorders, medication, and disturbances of the central nervous system. There is no permanent treatment method of bruxism, so the objectives for management of bruxism are reduction of psychological stress and treatment of signs and symptoms of bruxism by occlusal adjustment, occlusal splint, systemic medication and physical therapy. These cases report present three cases of children with bruxism. The bruxism was reduced in these patients wearing occlusal splint.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.489-494
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• 2003

Odontomas are the common type of odontogenic tumors and generally they are asymptomatic, depending upon size, location and their limited growth potential. they are rarely diagnosed before the second decade of life, and the frequently lead to impaction or delayed eruption of permanent teeth. Odontomas are classified of compound as compound or complex by morphology. Complex odontomas are unorganized masses of odontogenic tissues, morphologically not resembling the teeth, account for approximately 25 percent of all odontomas, 22 percent of odontogenic tumor of the jaws, and have a predilection for the posterior mandible in males. The etiology of odontomas is unknown, although local trauma, infection, and genetic factors have been suggested. Usually, treatment of odontoma is conservative sugical removal and their is little probability of recurrence. This paper describes two cases of complex odontomas diagnosed in children due to impaction of maxillary first molar in all cases, the surgical excision of the lesions was performed. Follow-up after 2 years, showed spontaneous eruption of the first permanent molar to the occlusal plane.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.3
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• pp.299-305
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• 2016

The aim of this study was to identify the causative genetic mutation in a family with non-syndromic oligodontia. The 7-year-old female proband and her mother underwent oral examination, panoramic radiographs were obtained and blood samples were collected. All exons of the PAX9 gene were amplified by polymerase chain reaction and sequenced. The sequencing results were compared with the standard human gene sequence. The proband lacked 11 permanent teeth, and her mother lacked 19 permanent teeth. No other birth defects were observed. As a result of gene analysis, there was a novel heterozygous nonsense mutation (c.184G>T, $p.Glu62^*$) in exon 2 in both affected subjects. It is suspected that the nonsense mutation leads premature termination of translation, yields a truncated protein 280 amino acids shorter than the wild-type protein. These defects include parts of the paired box domain, a DNA-binding site that plays an essential role in protein function. Otherwise, more likely the mutant transcript would be degraded by nonsense-mediated decay system, resulting haploinsufficiency to cause oligodontia in this family.

• The korean journal of orthodontics
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• v.38 no.2
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• pp.95-103
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• 2008

Objective: This study was performed to investigate the labio/buccal clinical crown curvatures of Korean permanent teeth and to obtain the curve-ratio data in an attempt to fabricate bracket bases fit for each individual Korean permanent tooth. Methods: Three-dimensional digital models were made from 30 sets of dental casts with normal anatomic structures. According to the FA points, horizontal and vertical reference planes were established and lines were drawn on the tooth surfaces in reference to these planes. The curvature was expressed as the coefficient of a quadratic equation. Lines mesial, distal, gingival and occlusal to the horizontal, vertical reference planes and the FA point were drawn. Results: The curvature measured for each line revealed that there are no significant differences between male and female, except for maxillary canines and maxillary second bicuspids (p > 0.05). There were notable differences in the mesio-distal or gingivo-occlusal curvatures among the mandibular lateral incisors, maxillary canines, maxillary and mandibular first and second bicuspids and first molars (p < 0.05). Conclusions: The labial & buccal crown curvatures of teeth in Korean normal occlusion were measured on the mesial and distal, gingival and occlusal sides respectively in this study. Based on these data, a SWA can be developed to fit the individual features of Korean tooth crowns.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.15 no.1
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• pp.35-39
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• 2019

Oculo-cerebro-renal syndrome, known as Lowe syndrome, is an X-linked gene disorder characterized by congenital cataracts, brain abnormalities and renal dysfunction. Tooth crowding, taurodontism, delayed eruption in the permanent dentition and over-retained primary teeth with ectopic eruption of the permanent teeth have been reported as dental findings. Because of the high incidence of poor cooperation, patients with Lowe syndrome have difficulties in maintaining good oral hygiene, which may require dental treatment. We present a case of dental treatment for the uncooperative child with Lowe syndrome under general anesthesia. A 4-year-old, 11.2 kg boy with Lowe syndrome visited Seoul National University Dental Hospital for gingival swelling. The patient had multiple caries requiring dental treatment. Because of his past history of malignant hyperthermia during inhalation induction, anesthesia was induced and maintained with total intravenous anesthesia (TIVA) after medical consultation. Dental restorative treatments were successfully performed and no complications were observed during and after the procedure. Safe and effective dental management of the patients with Lowe syndrome could be performed with the help of general anesthesia and careful monitoring.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.3
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• pp.267-272
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• 2009

Bone grafting the alveolar cleft allows for stability and continuity of the dental arch, provides bone for eruption of permanent teeth or placement of dental implants, and gives support to the lateral ala of the nose. Closure of residual oronasal fistula can occur simultaneously. Repair of alveolar clefts can occur at a variety of stages defined as primary, early secondary, secondary, and late. Most centers perform this surgery as secondary bone grafting. Autogenous bone provides osteogenesis, osteoinduction and conduction and is recommended for grafting to the cleft alveolus and several donor sites are available. The surgeon should select the best flap design considering the amount of mucosa available, blood supply and tension-free closure, and the extent of the oronasal communication. The authors provide a comprehensive understanding of alveolar clefts and their repair by reviewing the historical perspective, objectives for treatment, timing, source of graft, presurgical orthodontics, surgical techniques, postoperative care, and complications.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.2
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• pp.150-160
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• 2005

Background: For normalization of displaced anatomical structure by large cyst, two-step procedure (decompression and enucleation afterward) has been recommended. However, the histological transformation after cystotomy for decompression was shown frequently in secondary enucleation. Therefore, analyses about effects and histological changes after decompression have been necessary. Methods: 48 cases diagnosed as large odontogenic cyst in the jaw and treated by decompression and secondary enucleation were retrospectively analyzed in clinical, rediographical, and histological aspects. Results: In dentigerous cyst, decompression was much useful. Impacted permanent teeth were erupted and reduction rate was higher than that of odontogenic keratocyst (OKC) and apical periodontal cyst. In OKC, among the 29 cases, 11 cases showed no-keratosis, proliferation and rete-ridge elongation after decompression. 4 cases showed no-keratosis, only. 7 cases showed orthokeratosis and rete-ridge elongation and 6 cases showed reteridge elongation, only. 1 case had no change. And the recurrence rate for OKCs was 10.3%. For all odontogenic cysts in this study, dysplasia was not found in cystic lining after decompression. Conclusions: This study implied that decompression for large odontogenic cyst was useful treatment modality because it was conservative treatment and recurrence rate was low although long treatment period was required.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.161-173
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• 1996

The cariostatic effect of fluoride had been established by many epidemiologic and experimental studies. But, there are still different views on the mechnism of cariostasis and remineralization, especially about the proper fluoride concentration. The purpose of this study is to ascertain the remineralization of caries lesion and influence of fluoride concentration which affect remineralization by a study based on dynamic mechanism. The subjects, sound permanent teeth without demineralization or crack, were immersed in lactic acid buffered demineralization solution for 4 days. Dental caries with surface zone and subsurface lesion were artificially produced. All specimens were immersed in lactic acid buffered remineralization solution which had fluoride concentrations of 1 ppm, 2 ppm, 3 ppm for 10days. Final conclusions were obtained by observing the specimens for every 10 days under polarized microscopy. 1. Remineralization of caries lesion as well as demineralization of enamel were produced by changing the degree of saturation of lactic acid buffer solution. 2. Remineralization of caries lesion was facillitated by fluoride ion in lactic acid buffer solution. but, remineralization of the entire caries lesion was not increased as fluoride ion concentration increased.