• The Journal of Advanced Prosthodontics
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• v.2 no.3
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• pp.65-70
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• 2010

Large oro-facial defects result from cancer treatment consequences in serious functional as well as cosmetic deformities. Acceptable cosmetic results usually can be obtained with a facial prosthesis. However, retention of a large facial prosthesis can be challenging because of its size and weight. This article describes prosthetic rehabilitation of a 57-year-old man having a right lateral mid-facial defect with intraoral-extraoral combination prosthesis. A modified technique to fabricate a hollow substructure in heat-polymerizing polymethyl-methacrylate to support silicone facial prosthesis was illustrated. The resultant facial prosthesis was structurally durable and light in weight facilitating the retention with magnets satisfactorily. This technique is advantageous as there is no need to fabricate the whole prosthesis again in case of damage of the silicone layer because the outer silicone layer can be removed and re-packed on the substructure if the gypsum-mold is preserved.

• Journal of Biomedical Engineering Research
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• v.31 no.4
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• pp.292-301
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• 2010

To restore visual sensation of blind patients, we have proposed a fully implantable retinal prosthesis comprising an three dimensionally (3D) stacked retinal chip for transforming optical signal to electrical signal, a flexible cable with stimulus electrode array for stimulating retina cells, and coupling coils for power transmission. The 3D stacked retinal chip is consisted of several LSI chips such as photodetector, signal processing circuit, and stimulus current generator. They are vertically stacked and electrically connected using 3D integration technology. Our retinal prosthesis has a small size and lightweight with high resolution, therefore it could increase the patients` quality of life (QOL). For realizing the fully implantable retinal prosthesis, we developed a retinal prosthesis module comprising a retinal prosthesis chip and a flexible cable with stimulus electrode array for generating optimal stimulus current. In this study, we used a 2D retinal chip as a prototype retinal prosthesis chip. We fabricated the polymide-based flexible cable of $20{\mu}m$ thickness where 16 channels Pt stimulus electrode array was formed in the cable. Pt electrode has an impedance of $9.9k{\Omega}$ at 400Hz frequency. The retinal prosthesis chip was mounted on the flexible cable by an epoxy and electrically connected by Au wire. The retinal prosthesis chip was cappted by a silicone to pretect from corrosive environments in an eyeball. Then, the fabricated retinal prosthesis module was implanted into an eyeball of a rabbit. We successfully recorded electrically evoked potential (EEP) elicited from the rabbit brain by the current stimulation supplied from the implanted retinal prosthesis module. EEP amplitude was increased linearly with illumination intensity and irradiation time of incident light. The retinal prosthesis chip was well functioned after implanting into the eyeball of the rabbit.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.4
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• pp.423-430
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• 2016

The implant prosthesis can be divided into the screw retained prosthesis and cement retained prosthesis. Each type has advantages as well as disadvantages which is unfavorable to maintain the implants. To overcome these drawbacks, T-screw system was developed. T-screw system which utilizes a lingual direction of the screw to retain the implant prosthesis, has advantages of retrievability of the prosthesis, passive fit, and possibility to form esthetic and functional occlusal surface. The prior prosthesis which utilized horizontal screws had difficulty in fabrication especially in the case of multiple units, and also limited use with all-ceramic prosthesis. In this case, fabricating the implant prosthesis by using the T-screw system showed superior results in easy maintenance, esthetics, and also functions. In addition, we are to report the method of using the T-screw system in implant prosthesis, such as multiple units of implant prosthesis and all ceramic prosthesis.

• Journal of Technologic Dentistry
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• v.31 no.3
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• pp.59-66
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• 2009

In this study 240 geriatric patients, aged 60 year and over were evaluated using a questionnaire and oral examination for their oral status, demand and satisfaction of prosthesis treatment. 1. The single main complaint was regarding from the existing removable prosthesis. When the complaints were catagorized into larger groups, complaints regarding existing prosthesis were 32% and followed by 30% in caries and endodontic problems. 2. DMFT index woman appeared the man the age when will increase more highly recording where highly and considered statistically. 3. According to the result from questionnaire, 48% of patients wearing removable prosthesis and 43% with fixed prosthesis were not satisfied with existing prosthesis. Thirty-seven percentages of patients were not satisfied with aesthetics and unable to chew food properly. 4. Thirty-nine percentage of patients were wearing removable prosthesis. More complete dentures were found on maxilla and partial dentures on mandible. 5. Seventy-seven percentage of patients requested for new prosthesis and the majority of these patients had complaints of difficulties in chewing and discomfort.

• Journal of Technologic Dentistry
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• v.40 no.3
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• pp.173-180
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• 2018

Purpose: The purpose of this study was to verify the remake rate and cause of dental prosthesis and to investigate major factors of remake of dental prosthesis. Methods: This study carried out self-administered questionnaire survey from 126 nationwide dental laboratory CEO and directors, which was conducted from September to October in 2016. Results: Total remake rate of dental prosthesis was 10.1% at the nationwide dental laboratories. It was in order of remake rate of dental prosthesis 11.8% for CAD/CAM, 11.5% for porcelain and 11.0% for implant prosthesis. Error of clinical impression was the highest remake cause(63.7%). Nevertheless, dental laboratory take the responsibility of expense for remake of dental prosthesis, regardless of remake cause(67.4%). There was no relation between dental laboratory characteristics and the remake rate of dental prosthesis(p>.05). Conclusion : The remake rate of dental prostheses should be reduced to minimize the economic loss of dental laboratories and raise dental prosthesis satisfaction. It is required to communicate of dentist, dental technicians, and patients, moreover, undistorted information about oral environment should be provided to the dental technicians.

• Journal of Technologic Dentistry
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• v.29 no.2
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• pp.105-117
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• 2007

As a dental technician, the aim of the present study on maxillofacial prosthesis was to research its relation with dental technology and further development aspects by looking into its history, kinds, production materials and process. Dental technicians are to expect a great potential to work as maxillofacial prosthetist if having an interest in education of maxillofacial prosthesis field, and developing and operating the education process by expanding the range of dental technology. This article is to present overall history of maxillofacial prosthesis and some background information on the materials which have been used from the past. The maxillofacial field plays essential functions of mastication and speech, as well as performs appearance, which evokes good or bad feelings as an instant and instinctive response. The use of maxillofacial prostheses is not merely the replacement of a missing part of the face, resulted from injuries, but a rehabilitation process to help individuals come back to society. Rehabilitation includes both patient's physical and psychological recovery, such as self-esteem and selfconfidence. There has been a rapid development in application potentials of maxillofacial prosthesis technology which include implant, which can penetrate skin, and new materials. In order to produce maxillofacial prosthesis, general procedures of maxillofacial laboratory work should be understood first. Maxillofacial prosthesis and the dental prosthesis have many similarities in its academic perspective and originality. Maxillofacial prosthesis should be added into the curriculum for dental technology to achieve co-enhancement of the two fields.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.46-59
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• 1999

A fixed bridge is preferred as a prosthetic option supported by oral implants. However, it is very difficult to re tore edentulous maxilla with fixed prosthesis in cases with improper position and angulation of fixtures, abnormal jaw relation, and need for proper lip support. Six Br${\aa}$nemark implants were installed in edentulous maxilla opposing mandible with natural dentition. A removable hybrid prosthesis attached to a bar milled by 6 degrees was therefore designed to overcome such disadvantages of fixed prosthesis. Lateral stabilization of removable prosthesis was obtained by framework closely fitting the milled bar. Support for the prosthesis was ensured by three elevated areas on the bar. Two precision attachments(CEKA REVAX) provided appropriate direct and indirect retention without influencing support. A clinical and laboratory procedure was presented.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.10 no.1
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• pp.104-113
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• 2001

This article described a procedure for fabricating an esthetic gingival porcelain restoration as an implant-supported fixed prosthesis for edentulous maxilla. Alternative treatments for fully edentulous patients include an implant-supported overdenture or a fixed implant-supported prosthesis with bilateral distal cantilevers. But, from a functional and biomechanical point of view, the fixed implant-supported prosthesis with posterior cantilevers or implant-supported tissue-borne overdenture do not significantly improve masticatory effectiveness compared with a distributed implant restoration as a fixed implant-supported prosthesis. The fact that the prosthesis is supported by distributed implants over eight for edentulous maxilla in general, provides increased masticatory efficiency as a fixed restoration and similar gingival appearance with esthetic gingival porcelain. It is also detachable by dentist to allow easier after-care of soft tissue and the prosthesis.

• Journal of Korean society of Dental Hygiene
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• v.7 no.1
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• pp.15-30
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• 2007

The main objective of this study is to investigate the improvement of the quality of dental health based on the dental service satisfaction factors of the old dental prosthesis patients of more than 60 years of age who use the dental institutes including dental hospital, clinic, and public health center and to identify the interest in the dental prosthesis as changing paint. Across the country through a questionnaire survey of a question and answer type conducted by the trained dental hygienists or dentist's. Major results of the empirical analysis are as follows. 1. looking at variation of the variables of socio-demographic features of the respondents, the group of female, age distribution of 60-65, average monthly income of 0.5-1 million Won, and schooling background of college showed significant difference. And the prosthesis treatment in terms of the purpose of isiting a dental institute, and the dental clinic in terms of the type of visiting dental institute showed a remarkably significant difference. 2. looking at variation of variables of the general features of the respondents, a prosthesis satisfaction service in terms of age showed significant difference: a prosthesis satisfaction service, dental staffs' service and dental facilities' service in terms of average monthly income showed significant difference: the entire conditions except for the dental facilities' service in terms of schooling and general features showed significant difference: and in terms of the purpose of visiting dental institute, it showed no significant difference. In terms of a visiting dental institute, the prosthesis satisfaction service, dental facilities, overall level of satisfaction, result of treatment, word of mouth and revisit showed significant difference. 3. looking at variation of the variables of post-installation prosthesis satisfaction of the respondents, the prosthesis satisfaction service, dentist's dental service, staffs' service, dental facilities' service and revisit in terms of the prosthesis type: and the prosthesis satisfaction service, word of mouth, revisit and overall level of satisfaction from the perspective of serious concern showed significant difference. The prosthesis satisfaction service and dentist's service in terms of the solving the economic burden: and the entire variables in terms of dissatisfaction elements showed a similar level of significant difference 4. in regard to the satisfaction of dental service and the change of the recognition of prosthesis patients, it was revealed that the level of dental prosthesis satisfaction of the respondents was closely related to the dentist's service, staffs' service, and dental facilities' service. Finally, looking at the influence of the dental service on the treatment result, satisfaction, word of mouth, revisit and the overall satisfaction level, it was revealed that they had a great impact on the prosthesis satisfaction service.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.12 no.2
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• pp.152-157
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• 2001

Background : Electrolarynx, Esophageal voice, and Silicone voice prosthesis with tracheoesophageal(T-E) fistula have been used as vocal rehabilitating methods for the post-laryngectomized patients. Prosthetic rehabilitation of voice after total laryngectomy has gained wide acceptance and has become a common practice in many clinics since the pioneering works of Singer and Blom In 1979. Since the introduction of tracheo-esophageal puncture and application of Blom Singer$\circledR$ voice prosthesis in 1980, several reliable voice prostheses have been developed and are successfully being used. Objectives : Even though quality of voice produced by Silicone voice prosthesis with T-E fistula is superior to other modalities, it still has some disadvantages. We devised a new cannulatyped silicone voice prosthesis. Methods : 1) Devising a new prototype of cannula-typed silicone voice prosthesis. 2) Application of the prototype using canine animal model(laryngectormized dog) and fitting trial on human patient whose previously inserted Silicone voice prosthesis is not functioning due to presumed fungal infection. Discussion : Final form of prototype was made after several times of major and minor modifications. Insertion of the newly developed Cannula-typed Silicone voice prosthesis on canine animal model and human trial were done without any difficulty. There were no serious leakage of saliva or food during swallowing. Conclusion : The newly developed Cannula-typed Silicone voice prosthesis(So-Mang$\circledR$) and the modified replacement method will further improve the results of post-laryngectomized prosthetic voice rehabilitation. Long-term animal study and human trial are planned in the near future.