• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.141-141
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• 2015

In this study, a series of hydroxyaptite (HAp) are produced on Ti dental implant using electrochemical deposition. Based on the preliminary analysis of the coating structure, composition and morphology. In vitro studies were performed with MC3T3-E1 cell to investigate the effect of biological change on different surface conditions.

• The Journal of the Korean dental association
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• v.57 no.11
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• pp.708-713
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• 2019

Chronic obstructive inflammatory disease of salivary glands is the most frequent disease of the salivary glands and is characterized by recurrent swelling and pain caused by pressure. Sialography is recommended for the diagnosis of obstructive sialadenitis to observe changes in duct morphology, such as stricture and dilatation. Intraductal irrigation using normal saline is a simple treatment for patients with chronic obstructive inflammatory disease by removing the microlith and mucous plugs in the duct. It can be used as a conservative treatment option for resolving the obstructive symptoms.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.3
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• pp.241-252
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• 2022

The purpose of this study was to evaluate the relationship between sella turcica morphology and delayed dental age. In total, 389 participants under 16 years old were selected. Dental age was evaluated by the Demirjian method and age discrepancy (AD), the value subtracted from dental age to chronological age, was calculated. The participants were divided into 8 groups based on the sella turcica type. Bridging ratio (BR) was defined as interclinoid distance divided by sella turcica length to determine the degree of sella turcica bridging (STB) and the participants were classified into 4 groups by BR. The data were statistically analyzed using the Kruskal Wallis test and the Mann Whitney test. Some groups with sella turcica abnormality showed lower AD than that of the normal group and the AD differences varied from 4 months to 1.3 year. As the STB severity increased, AD decreased. AD differences varied from 7 months to 1.19 year. No distinct differences were observed in sella turcica type and STB groups according to sex. The results indicate that sella turcica morphology is associated with delayed dental age. Sella turcica can be used as a supplementary indicator to predict dental development.

• The Journal of the Korean dental association
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• v.55 no.1
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• pp.63-70
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• 2017

Materials and methods: Sixty extracted premolars were assigned to three groups according to the root canal system (Weine's classification; type I, II and III) of 20 teeth each using radiographic examination. The root tip was cut horizontally 1 mm from the anatomical apex and the apical cross-section was visualized using microscope at x50 magnification and photographed. Minimum and maximum apical root canal diameter of each tooth was measured and classified into three types by canal morphology (round, oval and flattened shape). Statistical analysis was performed to compare the apical root canal diameter and morphology according to the root canal system. Results: In apical root canal morphology at cross-sectional view, the most common shape was round in type I, flat in type II, and oval in type III. In apical root canal diameters at cross-sectional view, there was a significant difference between the minimum and maximum diameter in all types (p<0.05). The maximum diameter was 0.331 mm in type I, 0.519 mm in type II, and 0.310 mm in type III. There was a significant difference among type I, III and type II (p<0.05). Conclusion: The morphology and diameter of apical root canal was different according to the root canal system. Therefore, clinicians should consider the apical file size in view of the apical root canal shape according to the root canal system.

• Journal of Korean Dental Science
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• v.9 no.2
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• pp.49-54
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• 2016

Purpose: The purpose of this study was to assess the relationship between gingival biotype and underlying crestal bone morphology in the maxillary anterior region. Materials and Methods: The maxillary anterior teeth from 40 subjects (20 thin biotype, 20 thick biotype) with ages from 20 to 50 years were included in this study. All subjects had healthy gingiva in the maxillary anterior region and had no history of orthodontic treatment, periodontal treatment, or hyperplastic medication. Using the probe transparency method, the scalloped distance (SCD) between the contact point-bone crest and the midface-bone crest was measured for each maxillary anterior teeth of two groups. Result: The mean SCD was $3.00{\pm}0.21mm$ in thin biotype and $2.81{\pm}0.20mm$ in thick biotype. The SCD value in the thin biotype was statistically significantly greater than in the thick biotype (t=2.982, P<0.01). Comparing the degree of crestal bone scallop in each maxillary anterior teeth in the two groups, all six teeth in the thin biotype showed higher bone scallop than in the thick biotype. Conclusion: A simple procedure using a probe could to determine gingival biotype and to predict the underlying crestal bone morphology was introduced. This may be useful for effective treatment planning.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.543-564
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• 1993

A cephalometric study was undertaken to reveal significant differences of craniofacial morphology of operated congenital cleft lip and palate subjects and control subjects. The material for this study consisted of 73 subjects with operated congenital cleft lip and palate subjects(53 males, 20 females) and 110 control subjects (7 males, 34 females) ranging from 3 to 14 years old. Each group was divided into four age groups (3-5, 6-8, 9-11, 12-14 year) and analyzed by Cohen's method and Burstone's method. The following conclusions were obtained ; 1. In Wit's appraisal, there was no difference the cleft lip and palate subjects and the control subjects. 2. In the cleft lip and palate subjects, they had smaller and more retrusive maxilla than the control subjects in both sexes. 3. In the cleft lip and palate subjects, they had more retrusive mandible than the control subjects in both sexes. 4. In the cleft lip and palate subjects, they had more concave profile than the control subjects.

• The Journal of the Korean dental association
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• v.55 no.9
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• pp.592-603
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• 2017

Purpose: The effects of various concentrations of ascorbic acid on stem cell spheroids derived from intraoral areas are not known yet. Thus, the purpose of this study is to evaluate the effects of different concentrations of ascorbic acid on the morphology and cellular viability of stem cell spheroids derived from the gingival tissues. Materials and Methods: Stem cells were plated onto silicon elastomer-based concave microwells and grown in the presence of ascorbic acid at concentrations ranging from 0.003% to 0.3%. The morphology of the cells was viewed under an inverted microscope at day 1, 2, 3 and 5. Qualitative live/dead assay and quantitative cellular viability using Cell Counting Kit-8 were performed on day 2 and day 5. Results: Gingiva-derived stem cells formed spheroids irrespective of ascorbic acid concentration in silicon elastomer-based concave microwells. Increase in the diameter of spheroid were seen with higher concentrations of ascorbic acid. Higher cellular viability was seen in higher concentrations of ascorbic acid. Conclusion: Within the experimental setting, the application of ascorbic acid on stem-cell spheroids produced an increase in the size and higher viability with higher dosage. It can be suggested ascorbic acid be applied with stem cell spheroids for tissue engineering purposes.

• Imaging Science in Dentistry
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• v.50 no.2
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• pp.105-115
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• 2020

Purpose: This study investigated the position of the hyoid bone and its relationship with airway dimensions in different skeletal malocclusion classes using cone-beam computed tomography (CBCT). Materials and Methods: CBCT scans of 180 participants were categorized based on the A point-nasion-B point angle into class I, class II, and class III malocclusions. Eight linear and 2 angular hyoid parameters(H-C3, H-EB, H-PNS, H-Me, H-X, H-Y, H-[C3-Me], C3-Me, H-S-Ba, and H-N-S) were measured. A 3-dimensional airway model was designed to measure the minimum cross-sectional area, volume, and total and upper airway length. The mean crosssectional area, morphology, and location of the airway were also evaluated. Data were analyzed using analysis of variance and the Pearson correlation test, with P values <0.05 indicating statistical significance. Results: The mean airway volume differed significantly among the malocclusion classes(P<0.05). The smallest and largest volumes were noted in class II (2107.8±844.7 ㎣) and class III (2826.6±2505.3 ㎣), respectively. The means of most hyoid parameters (C3-Me, C3-H, H-Eb, H-Me, H-S-Ba, H-N-S, and H-PNS) differed significantly among the malocclusion classes. In all classes, H-Eb was correlated with the minimum cross-sectional area and airway morphology, and H-PNS was correlated with total airway length. A significant correlation was also noted between H-Y and total airway length in class II and III malocclusions and between H-Y and upper airway length in class I malocclusions. Conclusion: The position of the hyoid bone was associated with airway dimensions and should be considered during orthognathic surgery due to the risk of airway obstruction.

• Restorative Dentistry and Endodontics
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• v.46 no.1
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• pp.4.1-4.16
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• 2021

Objectives: This study evaluated the biocompatibility and bioactive potential of NeoMTA Plus mixed as a root canal sealer in comparison with MTA Fillapex. Materials and Methods: Polyethylene tubes filled with NeoMTA Plus (n = 20), MTA Fillapex (n = 20), or nothing (control group, CG; n = 20) were inserted into the connective tissue in the dorsal subcutaneous layer of rats. After 7, 15, 30 and 60 days, the specimens were processed for paraffin embedding. The capsule thickness, collagen content, and number of inflammatory cells (ICs) and interleukin-6 (IL-6) immunolabeled cells were measured. von Kossa-positive structures were evaluated and unstained sections were analyzed under polarized light. Two-way analysis of variance was performed, followed by the post hoc Tukey test (p ≤ 0.05). Results: At 7 days, the capsules around NeoMTA Plus and MTA Fillapex had more ICs and IL-6-immunostained cells than the CG. However, at 60 days, there was no significant difference in the IC number between NeoMTA Plus and the CG (p = 0.1137) or the MTA Fillapex group (p = 0.4062), although a greater number of IL-6-immunostained cells was observed in the MTA Fillapex group (p = 0.0353). From 7 to 60 days, the capsule thickness of the NeoMTA Plus and MTA Fillapex specimens significantly decreased, concomitantly with an increase in the collagen content. The capsules around root canal sealers showed positivity to the von Kossa stain and birefringent structures. Conclusions: The NeoMTA Plus root canal sealer is biocompatible and exhibits bioactive potential.

• Journal of Korean society of Dental Hygiene
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• v.7 no.2
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• pp.189-196
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• 2007

A study of the J health college dept of dental hygiene practice vistant a total of 35 supragingival calculus and subgingival calculus picking SEM observation and bacteria identification of the result are followings. 1. As observed by dental calculus SEM, the surface roughness appeared as peaks, valleys, and pits. 2. About bacteteria morphology blood agar plate small green zone partial hemolysis colony streptococcus observation 3. Isolated colony gram stain gram are positive display 4. Supragingival calculus at Lactococcus lactis spp. Leuconostoc spp. Streptococcus mitis, Aerococcus viridans bacteria 1, 3, 3, 16 species detection 5. Subgingival calculus at Aerococcus viridans, Leuconostoc spp. bacteria 5, 1 species detection.