• The Korean Journal of Health Service Management
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• v.4 no.2
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• pp.63-72
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• 2010

The present study purposed to prevent oral diseases and to improve oral health in children. For this purpose, we selected 70 cases who are 5~7 years old preschoolers at the kindergarten affiliated to G College in Gyeongsangbukdo, and analyzed the general patterns of oral care and the relation of the patterns with dental plaque and deciduous dental caries in the children. Specifically, we conducted oral examination and applied pit and fissure sealant according to the eruption of deciduous molar and first molar. In addition, we executed the 1st and 2nd tooth brushing instruction (TBI), and surveyed S-OHI and PHP twice. Excluding 14 preschoolers who did not appear in the 2nd survey, we performed the study with 56 preschoolers and drew conclusions as follows. 1. The number of decayed or missed or filled teeth among deciduous teeth was 3 or more in 42.9% of female children, and 46.4% of male children, so male children showed a slightly higher rate. 2. The degree of dental plaque formation was $1.64{\pm}1.22$ among the surveyed children. 3. The oral health index was lower after TBI than before in all the children (P<.001). 4. Change in the oral health index was particularly larger in 7 year old female children (p<.005). 5. The patient hygiene performance index was lower after TBI than before in both the buccal surface and lingual surface of the children (p<.005). 6. The patient hygiene performance index was lower after TBI than before in all of male children's teeth except the right maxillary first deciduous molar (p<.001).

• Imaging Science in Dentistry
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• v.37 no.3
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• pp.133-138
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• 2007

Purpose: The purpose of this study was to evaluate the morphologic features of posterior edentulous mandible for Korean patients using cross-sectional CT images. Materials and Methods: Computed tomographic cross-sectional views taken in 2004 and 2005 at Seoul National University Dental Hospital were analyzed by an oral and maxillofacial radiologist. Four indices were measured to meet the purpose of this study: 1) the horizontal distance between the alveolar crest and mandibular canal (Type), 2) the angle of the mandibular long axis (Angle), 3) the bucco-lingual location of mandibular canal, and 4) the depth of the submandibular fossa. The averages and standard deviations of the measurements were compared according to the location (the first and second molar area) and sex of the patients. Results: Statistically significant difference was found in Type, Angle, and submandibular fossa depth between the first and second molar area (p<0.05). However, there was no significant difference between men and women in any of the measured indices. Most of the mandibular canals were located in lingual side of posterior mandible. Conclusion: More care should be taken when an implant is installed on the mandibular second molar area.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.2
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• pp.106-111
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• 2009

Bisphosphonates have been approved for Paget's disease, cancer-related hypercalcemia, bone involvement in multiple myeloma or solid tumors and osteoporosis. Although, underlying pathophysiological mechanisms remain unclear, it seems that bisphosphonates inhibit osteoclast precursor cells, modulate migratory and adhesive characteristics and induce apoptosis of osteoclasts. Furthermore impacts on angiogenesis, microenvironment and signal transduction between osteoclasts and osteoblasts. In this report, we present a case of oral bisphosphonates induced osteonecrosis of the mandible in a 84-year-old patient who received for two years. Two tapered screw vent implants(Zimmer, USA) were placed in the area of first and second molar. Two weeks later after crowns restored, some inflammatory signs and symptoms were observed on the second molar area. Sequestrum was formed and the sequestrum was removed with the implant. Frequent follow-up checks and oral hygiene maintenances were done and the first molar implant was restored. There is insufficient evidence suggests that duration of oral bisphosphonate therapy correlates with the development and severity of osteonecrosis. Therefore, dentists should not overlook the possibility of development of bisphosphonate induced osteonecrosis in patients who have taken oral forms of medication for less than three years.

• Journal of Korean Dental Science
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• v.7 no.2
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• pp.66-79
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• 2014

Purpose: To analyze the amount and pattern of tooth movement and the changes in arch dimension of mandibular dentition after orthodontic treatment using a new three-dimensional (3D)-indirect superimposition method. Materials and Methods: The samples consisted of fifteen adult patients with class I bialveolar protrusion and minimal anterior crowding, treated by extraction of four first premolars with conventional sliding mechanics. After superimposition of 3D-virtual maxillary models before and after treatment using best-fit method, 3D-virtual mandibular model at each stage was placed into a common coordinate of superimposition using 3D-bite information, which resulted in 3D-indirect superimposition for mandibular dentition. The changes in mandibular dental and arch dimensional variables were measured with Rapidform 2006 (INUS Technology). Paired t-test was used for statistical analysis. Result: The anterior teeth moved backward, displaced laterally, and inclined lingually. The posterior teeth showed statistically significant contraction toward midsagittal plane. The amounts of backward movement of anterior teeth and forward movement of posterior teeth showed a ratio of 6 : 1. Although the inter-canine width increased slightly (0.8 mm, P<0.05), the inter-second premolar, inter-first molar, and inter-second molar widths decreased significantly with similar amounts (2.2 mm, P<0.05; 2.3 mm, P<0.01; 2.3 mm, P<0.001). The molar depth decreased (6.7 mm, P<0.001) but canine depth did not change. Conclusion: A new 3D-indirect superimposition of the mandibular dentitions using best-fit method and 3D-bite information can present a guideline for virtual treatment planning in terms of tooth position and arch dimension.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.2
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• pp.104-111
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• 2015

Purpose: The aim of this retrospective study was to investigate the prevalence rate and types of C-shaped roots and C-shaped canal in maxillary molars by analyzing cone-beam computed tomography (CBCT) in a Korean population. Materials and Methods: Total of 357 CBCT images of maxillary molars (186 first molar, 171 second molar) were evaluated by two Endodontic specialists. Results: Eight types of C-shaped roots and 5 types of C-shaped canals were founded, the prevalence rate of C-shaped roots and canals were 21.0% and 5.3% respectively. Conclusion: These anatomical variations were more frequent in second molars than the first molars. Clinicians should have anatomical knowledge about various types of C-shaped root and root canal for successful root canal therapy.

• Journal of Oral Medicine and Pain
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• v.46 no.4
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• pp.125-130
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• 2021

Purpose: The dental age estimation of children is performed using dental maturity. Postmortem missing of the anterior teeth or the distortion of image of the anterior teeth in panoramic radiographs can make it difficult to analyze the development of the anterior teeth. This pilot study was conducted to derive a new age estimation method based only on the developmental stage of mandibular posterior teeth. Methods: This study was conducted using panoramic radiographs of 650 subjects aged 3 to 15 years old. The dental developmental stages of the lower left first premolar, second premolar, first molar and second molar were evaluated according to the Demirjian's criteria. The intra-/inter-observer reliability was evaluated, and multiple linear regression analyses were performed including the developmental stage of each tooth as an independent variable. Results: The intra-/inter-observer reliability was 0.9626 and 0.8877, respectively, and showed very high reproducibility. Multiple linear regression analyses were performed for males and females, and the age calculation table was derived by obtaining the intercept and the coefficient according to the development stage of each tooth. The coefficient of determination (r²) of the age calculation method was 0.9634 for male and 0.9570 for female subjects, and the mean difference between chronological age and estimated dental age was -0.42 and -0.21, respectively. Conclusions: This pilot study evaluated the developmental stages of four lower posterior teeth in the Korean group according to Demirjian's criteria, and derived age estimation method. The accuracy was lower than when more teeth were used, but it will be useful to estimate age of children when the anterior teeth are difficult to accurately analyze.

• Proceedings of the KACD Conference
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• 2002.11a
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• pp.680-680
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• 2002

No Abstract, See Full Text

• Journal of Periodontal and Implant Science
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• v.21 no.2
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• pp.187-187
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• 1991

• Journal of Periodontal and Implant Science
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• v.22 no.1
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• pp.202-202
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• 1992

• 대한치과보철학회:학술대회논문집
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• 2003.04a
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• pp.101-101
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• 2003