• 대한치과의사협회지
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• 제11권1호
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• pp.41-44
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• 1973

The experiment consisted of cementing full veneer crown of extracted teeth and a standardized cylindrical metal dies (6mm diameter, 6mm height, 1mm shoulder) and then measuring the tensile strength required to remove the cemented restoratoins by the Instron testing machine in the Korea Institude of Science and Technology. The Instron machine was operated at a rate of loading of 0.2cm per minute. From the experiments, the following results obtained. 1. The tension of zinc phosphate and alumina EBA cements were highest all of the cements. 2. The tension of Fynal and the addition of eugenol to zinc Phosphate cements were similar. The addition of eugenol to zinc phosphate cement was half stength and Fynal cement was on third strength than zinc phosphate cement. 3. The tension of zinc oxide-eugenol cement was lowest all of the cements.

• 대한치과의사협회지
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• 제10권2호
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• pp.121-128
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• 1972

14 patients, whose were attacked pain dysfunction syndrome of temporomandibular joint in Dental College Infirmary, Seoul National University from June 1970 to Dec. 1971, were examined regarding to clinical observation and electromyographical analysis. This paper established the followings: 1. Especially young female was more frequently attacked by pain dysfunction syndrome of Temporomandibular joint. 2. It is suggested that most of joint pain was occurred initially in opening mouth and forcible bite, and left side is more attacked than right side. 3. It was possible that this dysfunction can be occurred by open-bite, premature contact and ill-fitting prosthetic restoration. 4. Hoby, habit and bruxism as causal factors are not markedly related with this dysfunction. 5. Pain attacked regions, in most patients, are preauricular, joint itself, infra-auricular, cervical and external auditory meatus region. 6. In electromyographical studis, the musle activities of affected side of pain dysfunction syndrome are more strong than that of opposite side.

• 대한치과의사협회지
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• 제48권12호
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• pp.868-879
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• 2010

Adjunctive orthodontic therapy may be required to create appropriate space, to address misalignment and tooth size discrepancy for better function and esthetics. The desired interproximal alveolar contour and gingival embrasure form can be developed during treatment. Various applications of temporary anchorage devices for pre-prosthetic tooth movement allowed clinicians to achieve high efficiency, shorter treatment time, and less discomfort of patient. Biomechanical considerations for the periodontal status of the affected teeth are required to successfully control the vertical and horizontal space. Hence, the interdisciplinary approaches have an essential role in maximizing the favorable treatment outcome. In particular, pivotal Clinical decisions such as whether to open or close the space should be made by consensus of the involved dentists. This article presents the orthodontic treatment approaches for prosthodontic works including mesiodistal and vertical space regaining specially for cases of unrestored teeth over an extended period of time.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.562-565
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• 2002

Recent technologic innovations have created possibilities for restorative dentistry, such as computer-aided design and computer-aided manufacturing. This article presents a CAD process that has been developed for the fabrication of dental restorations. This process uses a 4-axes driving mechanism and an improved optical displacement sensor, successfully applied in other industries. In optical displacement sensor, the light beam emitted from the LED is converged through the light source lenses and thrown on the object to be detected. When the light beam is reflected from the object, however, it is diffused. The diffused light beam is converged again by the receiver lenses and cast on the optical position detector element as a small spot.

• 대한치과의사협회지
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• 제51권11호
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• pp.586-594
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• 2013

The critical factors affecting the esthetics of anterior implants can be summarized as following: 1) Correct positioning of implant fixture 2) Enough amount of alveolar bone 3) Optimum volume of soft tissue. The position of implant is probably the most important factor in obtaining esthetic treatment outcome. The 3-dimensional orientation of implant is determined by the position on the alveolar ridge and its direction. Clinicians often try to mimic natural teeth when fabricating restorations. During the course of esthetic diagnosis and treatment, however, one should not forget to consider the correlation between facial pattern, lips, gingiva, alveolar ridge, as well as remaining dentition. Since anterior region is biologically unfavorable when compared with posterior region, one minor discrepancy in positioning of implant can cause esthetically undesirable treatment outcome. If one understands the biological and prosthetic meaning of implant's 3-dimensional position, he or she can achieve superior esthetic outcome in anterior region.

• The Journal of Advanced Prosthodontics
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• 제2권1호
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• pp.1-3
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• 2010

BACKGROUND. Even though excellent impression materials are now available for making accurate replication for hard and soft tissue, the numerous dentists have faced lots of obstacles in making simultaneous impressions of multiple abutments. CASE DESCRIPTION. This article describes a modified method of tray fabrication using auto-polymerizing acrylic resin and impression technique for multiple prepared teeth in cases with limitations and difficulties in taking dental impressions. CLINICAL IMPLICATION. This segmental tray technique has several advantages, including higher impression quality, fewer impressions, and being more comfortable for the patient and less stressful for the clinician.

• The Journal of Advanced Prosthodontics
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• 제4권4호
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• pp.243-247
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• 2012

The velopharynx is a tridimensional muscular valve located between the oral and nasal cavities, consisting of the lateral and posterior pharyngeal walls and the soft palate, and controls the passage of air. Velopharyngeal insufficiency may take place when the velopharyngeal valve is unable to perform its own closing, due to a lack of tissue or lack of proper movement. Treatment options include surgical correction, prosthetic rehabilitation, and speech therapy; though optimal results often require a multidisciplinary approach for the restoration of both anatomical and physiological defect. We report a case of 56 year old male patient presenting with hypernasal speech pattern and velopharyngeal insufficiency secondary to cleft palate which had been surgically corrected 18 years ago. The patient was treated with a combination of speech therapy and palatal lift prosthesis employing interim prostheses in various phases before the insertion of definitive appliance. This phase-wise treatment plan helped to improve patient's compliance and final outcome.

• 대한치과보철학회지
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• 제44권5호
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• pp.628-641
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• 2006

Statement of problem: Dental magnetic materials have been applied to removable prosthetic appliances, maxillofacial prostheses, obturator and dental implant but they still have some problems such as low corrosion resistance in oral environments. Purpose: To increase the corrosion resistance of dental magnetic materials, surfaces of Sm-Co and Nd-Fe-B based magnetic materials were plated with TiN and sealed with stainless steels. Materials and methods : Surfaces of Sm-Co and Nd-Fe-B based magnetic materials were plated with TiN and sealed with stainless steels, and then three kinds of electrochemical corrosion test were performed in 0.9% NaCl solution; potentiodynamic, potentiostatic, and electrochemical impedance test. From this study, corrosion behavior, amount of elements released, mean average surface roughness values, the changing of retention force, and magnetic force values were measured comparing with control group of non-coated magnetic materials. Results: The values of surface roughness of TiN coated Sm-Co and TiN coated Nd-Fe-B based magnetic materials were lower than those of non coated Sm-Co and Nd-Fe-B alloy. From results of potentiodynamic test, the passive current density of TiN coated Sm-Co alloy were smaller than those of TiN coated Nd-Fe-B alloy and non coated alloys in 0.9% NaCl solution. From results of potentiostatic and electrochemical impedance test, the surface stability of the TiN coated Sm-Co alloy was more drastically increased than that of the TiN coated Nd-Fe-B alloy and non-coated alloy. The retention and magnetic force after and before corrosion test did not change in the case of TiN coated magnetic alloy sealed with stainless steel. Conclusion: It is considered that the corrosion problem and improvement for surface stability of dental magnetic materials could be solved by ion plating with TiN on the surface of dental magnetic materials and by sealing with stainless steels.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권1호
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• pp.41-45
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• 2009

Background: Reduced bone height is one of the major problems faced in restoring tooth loss with implants. By the use of short implants, it is possible to reduce complicated and invasive treatment such as bone graft, allowing more simple surgery. But short implants are generally considered to have lower success rates than that of standard implants. Purpose: To assess the results of short Straumann implants by a retrospective study of short Straumann implants with TPS(titanium plasma-sprayed) and SLA(sandblasted, large grit, acid etched) surfaces. Materials and methods: 173 implants in 106 patients who received short Straumann implant surgery(${\le}8\;mm$) in the department of oral and maxillofacial surgery, Kyunghee Dental Hospital, from February 1996 to October 2006 were selected and studied. All of the implants were followed up after prosthetic rehabilitation. The average follow-up period was 34 months with 119 months as the longest follow up period. The average follow-up period after prosthetic rehabilitation was 31 months. 64 females(60.4%) and 42 males(39.6%) participated in the research with the age range of 19 to 85(mean age 47). 20 patients(18.9%) were under 40, 85 patients(80.2%) were over 40 and under 70, and only one patient(0.9%) was over 70 years old. Results: 27 implants(15.6%) had TPS surface while 146 implants(84.4%) had SLA surface. 9 implants(5.2%) were 3.3, 108 implans(62.4%) were 4.1mm and 56 implants(32.4%) were 4.8mm in diameter. 167 implants(96.5%) were 8mm and 6 implants(3.5%) were 6mm in length. There were 24 implants(13.9%) on the maxillas and 149 implants(68.8%) on the mandibles. 119 implants(68.8%) were rehabilitated with FPD(fixed partial denture), 47 implants(27.2%) with single crowns and 4 implants(2.3%) with overdentures. Among the fixed partial dentures, 30 of them were splinted with short implants only. After over an year of follow-up period, 139 implants(96.5%) out of 144 implants showed marginal bone loss of less than 1mm. 3 out of 173 implants failed showing 98.27% survival rate. Conclusions: The use of short Straumann implants(${\le}8mm$) can be a simple and reliable treatment method in minimal residual bone height.

• 치위생과학회지
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• 제18권3호
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• pp.182-187
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• 2018

As the elderly population increases, they are increasingly affected by oral health problems. Therefore, efforts are being made to improve the oral health of older people, alleviate mental discomfort, and reduce unmet dental needs. This study was conducted to confirm the relationship between the National Health Insurance Elderly Denture Coverage and the unmet dental need for the edentulous elderly, as part of the protection policy. We analyzed the 2011 and 2013 Community Health Survey data of the edentulous elderly, aged 75 years or older, before 2012. In order to more precisely confirm the effects of the denture donation policy on unmet dental care, basic life recipients who were subject to the free elderly prosthetic project were excluded from the analysis. The final analysis included 20,400 subjects. According to our investigation of the factors that affect the unmet dental needs of the elderly, the National Health Insurance Elderly Denture Coverage did not affect unmet dental needs. The statistically significant variables that affected the unmet dental needs of the elderly were education and income levels, which are representative socioeconomic status variables. The lower the level of education, the unhealthier the dental care experience, and income levels showed a similar tendency. The elderly who have a low socioeconomic status are more likely to experience unmet dental needs because they lack the knowledge and socioeconomic ability to pay for dental care. Therefore, the policy for health protection of the entire elderly population should be continuously expanded. In addition, the socioeconomically vulnerable groups may have health problems due to the restriction of medical use, which may lead to quality of life deterioration.