• The Journal of Advanced Prosthodontics
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• v.7 no.6
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• pp.431-436
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• 2015

PURPOSE. The aim of this study was to evaluate occlusal contacts generated by 3 different biogeneric design modes (individual (BI), copy (BC), reference (BR)) of CEREC software and to assess the designs subjectively. MATERIALS AND METHODS. Ten pairs of maxillary and mandibular casts were obtained from full dentate individuals. Gypsum cast contacts were quantified with articulating paper and digital impressions were taken. Then, all ceramic crown preparation was performed on the left first molar teeth and digital impressions of prepared teeth were made. BI, BC, and BR crowns were designed. Occlusal images of designs including occlusal contacts were superimposed on the gypsum cast images and corresponding contacts were determined. Three designs were evaluated by the students. RESULTS. The results of the study revealed that there was significant difference among the number of contacts of gypsum cast and digital models (P<.05). The comparison of the percentage of virtual contacts of three crown designs which were identical to the contacts of original gypsum cast revealed that BI and BR designs showed significantly higher percentages of identical contacts compared with BC design (P<.05). Subjective assessment revealed that students generally found BI designs and BR designs natural regarding naturalness of fissure morphology and cusp shape and cusp tip position. For general occlusal morphology, student groups generally found BI design "too strong" or "perfect", BC design "too weak", and BR design "perfect". CONCLUSION. On a prepared tooth, three different biogeneric design modes of a CAD/CAM software reveals different crown designs regarding occlusal contacts and morphology.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.4
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• pp.407-421
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• 2012

Orthodontic problems of the oral maxillofacial area could be classified into skeletal and dental problems. Dental problems might cause various occlusal disharmony and among them congenital missing or eruption failure might cause not only functional problems but also esthetic problems. Additional psychological problems are also one of the reasons for patients seeking treatment. In cases showing eruption failure of many teeth in the maxilla, not only occlusal and esthetic problems but also difficulty in alveolar bone maintainment could occur. Therefore, successive approach is necessary when multiple teeth show eruption problems. In this case, a patient with eruption problems of #13, 12, 11, 23, 43 was successfully treated by surgical exposure and successive orthodontic extrusion resulting perfect occlusion. By additional periodontal treatment, gingival recession that occurred along with teeth eruption was solved. The impacted right mandibular canine was erupted successfully only by natural arch expansion and leeway space without any special surgical treatment.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.4
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• pp.307-313
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• 2016

Overdenture is one of the methods of patients with severely worn dentition. Remaining natural teeth help preserve alveolar bone and proprioception and provide rigid support. Also, overdenture distributes the concentrated stress applied to the abutment tooth and denture supporting tissues. There is an advantage that it can provide long-term stability to denture. In this case, the patient with only a few teeth due to severe wear and caries was satisfied with good function and favorable esthetics by using overdenture.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.3
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• pp.501-532
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• 1996

This study investigated the effects of cantilever length, location and load condition on stress distribution developed in the implants, prostheses and supporting tissues. The osseointegrated prostheses with two 10mm Branemark implants at 2nd premolar and 1st molar sites with cantilever extensions at 1st premolar, 2nd and 3rd molar sites were constructed. Under 100N, 200N of vertical and $45^{\circ}$ oblique loads at the cantilever pontics, stress distribution patterns and displacement were analyzed with three dimensional finite element method. The results were as follows : 1. The stress was concentrated at the joint of the cantilever pontic and implant superstructure, the neck of implant and the ridge crest near the cantilever But there was little load transfer to the lower supporting tissues of implants. 2. The implant near the cantilever was displaced inferiorly while the implant far from the cantilever was displaced superiorly. In horizontal direction the implants were displaced to the direction where the loads were applied, except the apexes of the implants. 3. In case of anterior cantilever, the stress and displacement were higher than the prosthesis connected with natural tooth. 4. The stress developed in the posterior cantilevered type was higher than in the anterior cantilevered type. The greastest stress was concentrated at the ridge crest near the posterior cantilever. 5. The longer the cantilever, the more the stress was developed and was concentrated at the joint of the cantilever pontic and implant superstructure. 6. Under oblique load, the stress was concentrated at the necks of implants and the ridge crests, but decreased at the joint of the cantilever pontic and implant superstructure than under vertical load.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.31.1-31.20
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• 2020

Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (synthetic-peptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.

• Restorative Dentistry and Endodontics
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• v.36 no.2
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• pp.114-118
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• 2011

Objectives: This study was aimed to examine the patients' perception and satisfaction with the results of endodontic microsurgery which was apicoectomy with retrofilling. Materials and Methods: A questionnaire was given to 109 patients, who were recalled after a minimum of 3 months upon endodontic microsurgery in the Department of Conservative Dentistry, Yonsei University. A contingency table and correlation analysis were used to determine if there were any correlations between age/gender and the patients' responses (p = 0.05). Results: Approximately 60% of respondents answered they had never heard of surgical endodontic procedures. 63.3% of respondents chose the surgical option because they wanted to keep their natural teeth. If the patient required the same procedure on another tooth later, 100 out of 109 respondents answered they would choose microsurgery instead of extraction. Most patients (82.57%) appeared to be satisfied with the surgical procedure. Conclusions: Endodontic microsurgery consisting of apicoectomy and retrofilling seems to appeal to majority of patients as a satisfactory and valuable treatment choice.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.469-477
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• 2021

For successful restoration of maxillary anterior implants, both pink esthetics and white esthetics must be satisfied. For pink esthetic part, the role of appropriate provisional prosthesis restoration is important, and for white esthetic part, the color and shape of the definitive prosthesis is important. Multilayer zirconia can be used for natural tooth appearance due to the higher transparency of the incisal area compared to the conventional monolithic zirconia. Therefore, in this case, white esthetic part was achieved through multilayer zirconia after recovering function and esthetics through appropriate provisional prosthesis in a patient who lost the maxillary anterior teeth.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.896-903
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• 2019

Objective: Qianbei-Pockmarked goats are affected by a disorder locally referred to as 'Ruanguzheng Disorder', which is characterized by emaciation, lameness, muscular relaxation, stiffness of the extremities, and abnormal curvatures of the long bones. Our objective was to determine the relationship between the disorder and phosphorus deficiency. Methods: Tissue samples were collected from affected and healthy animals, while soil and herbage samples were collected from affected and healthy pastures. Biochemical parameters were determined using an automatic biochemical analyzer (OLYMPUS AU 640, Olympus Optical Co., Tokyo, Japan). Mineral contents in soil, forage, and tissue were determined using a Perkin-Elmer AAS5000 atomic absorption spectrophotometer (Perkin-Elmer, Norwalk, CT, USA). Results: The results showed that phosphorus contents in herbages from affected pastures were markedly lower than those from healthy areas (p<0.01), and the ratio of calcium to phosphorus in the affected herbages was 12.93:1. The phosphorus contents of wool, blood, tooth, and bone from affected animals were also markedly lower than those from healthy animals (p<0.01). Serum phosphorus values in affected animals were much lower than those in healthy animals, while serum alkaline phosphatase values from affected animals were markedly higher than those from healthy animals (p<0.01). Inorganic phosphorus values from affected animals were approximately half of that in the control group. Supplementation of disodium hydrogen phosphate prevented and cured the disorder. Conclusion: This study demonstrates that Ruanguzheng disorder in Qianbei-Pockmarked goats is primarily caused by phosphorus deficiencies in herbage due to fenced pastures and natural habitat fragmentation.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.454-459
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• 2020

The main cause of oral disease is the formation of tooth surface bacteria, and a chemical mouthwash is used as a suppression method. However, chemical preparations have side effects, so we tried to verify the antibacterial effect of bamboo extract against oral microbes. Subjects were 15 college students as a control group and an experimental group, and the changes in oral microbes before and after the use of distilled water and bamboo extract were compared. Analysis of SPSS Windows ver. 20.0 was used (p<0.05). Results The total number of pathogenic microorganisms further decreased after using bamboo extract solution after using gargling solution between groups.

• Natural Product Sciences
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• v.26 no.4
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• pp.326-333
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• 2020

The aerial parts of Eclipta prostrata is used as a traditional medicine and vegetable. In traditional folk medicine, it is used for treatment of hemorrhages, hepatic, disease, renal injuries, hair loss, tooth mobility, and viper bites. In this study, ten compounds (1 - 10) were isolated from the aerial parts of E. prostrata. A reliable high performance liquid chromatography equipped with photometric diode array detector (HPLC-PDA) method was developed to simultaneously quantitate 10 marker compounds [chlorogenic acid (1), paratensein 7-O-��-ᴅ-glucoside (2), quercetin 7-O-��-ᴅ-glucoside (3), luteolin 7-O-��-ᴅ-glucoside (4), apigenin 7-O-��-ᴅ-glucoside (5), apigenin 4'-O-��-ᴅ-glucoside (6), apigenin (7), luteolin (8), wedelolactone (9), and paratensein (10)]. In addition, compounds 5 and 6 showed considerable inhibitory effects against protein-tyrosine phosphatase 1B (PTP1B) enzyme. Moreover, compounds 6 - 8, and 10 exhibited potent α-glucosidase inhibitory effects with IC50 values of 24.5 ± 1.9, 33.0 ± 0.5, 45.5 ± 0.1, and 23.8 ± 1.0 µM, respectively. All compounds (1 - 10) showed considerable acetylcholinesterase (AChE) inhibitory effects with IC50 ranging from 30.1 to 75.2 µM.