• The Journal of Korean Academy of Prosthodontics
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• v.31 no.1
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• pp.87-99
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• 1993

Many studies have been reported on the successful replacement of missing teeth with osseointegrated dental Implants. However, little research has been carried out on the bio-mechanical aspect of the stress on the surrounding bone of the free-standing type of dental implant prostheses. This experimental study was aimed to analyze the stress distribution pattern on the supporting tissues depending upon the position of osseointegrated implants supporting fixed bridges. In the cases of unilateral partially edentulous mandible (the 2nd premolar and the 1st and 2nd molars missing), two osseointegrated implants were placed at the 2nd premolar and 2nd molar sites (Model A) , the 1st and 2nd molar sites (Model B, Anterior cantilevered type), the 2nd premolar and 1st molar sites (Model C, Posterior cantilevered type). Chewing forces of dentate patients and denture wearer were applied vertically on the 2nd premolar, the 1st molar, and the 2nd molar of each model. A 3-Unit fixed partial denture was constructed at each model and cantilevered extension parts were involved in Model B and Model C. Two dimensional finite element analysis was undertaken. The commercial software (Super SAP) for IBM 16 bit personal computer was utilized. The results were as follows : 1. The magnitude of applied load influenced on the total value of stresses, but did not in-fluence on the pattern of stress distribution. 2. The magnitude of stress developed from the supporting tissues were in order of Model C,Model A,Model B. 3. High stresses were concentrated on the cervical and apical portion of the implant/bone interface. 4. A difference of the stress magnitude on the implant/bone interface between mesial and distal implant was most prominant in Model C and in order of Model A and Model B. 5. The stresses developed in Model A were evenly distributed throughout both implants. 6. The stresses concentrated on the cervical portion of cantilevered side were higher in the posterior cantilevered type than in the anterior cantilevered type.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.3
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• pp.145-154
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• 2001

In the past, many dentist were interested mainly in the mechanical aspects such as tooth preparation and retainer types for making dental restoration. But, these days, the concept of restorative treatment emphasizes the importarce of gnatic system and masticatory muscles in addition to oral cavity. So, the current considerations for the fixed prosthodontic treatment include the stabilization of temporomandibular joint and neuromuscualr system and the relationship of periodontal ligament and occlusion. To achieve the above objectives, occlusal splint has been used as one of the mouth preparations for restorative treatment. The objectives of occlusal splint are as follows; 1. To use as preliminary application for periodontal-occlusal treatment 2. To provide proper vertical dimension 3. To control abnormal habits and parafunction 4. To treat the temporomandibular disease and myofascial pain 5. To establish the new therapeutic position In some cases, the patients had improper vertical dimension and occlusal interferences caused by prostheses reconstucted using centric relation recorded without considering the health of TMJ and manticatory muscle. And these prosthesis act as primary source that cause pathologic phenomenon in periodontal ligament, muscles and TMJ. Physiologically, in order to make the treatment occlusion guided by proper centric relation method, the method should be guided after the use of occlusal splint for some period. The main objective of prosthetic treatment is to maintain the function and health of stomatognathic system. So, one of the most important things that have to be performed by clinicians is a clinical ability to do the correct diagnosis and treatment planning based on the stomatognatic function and occlusion.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.31.1-31.7
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• 2016

Background: The objective of this retrospective study was to show results from platform-switched narrow-diameter implants in the posterior edentulous region, which we followed up for more than 1 year after functional loading. Methods: Ninety-eight narrow implants were inserted into 66 patients. After healing, fixed implant-supported prostheses were delivered to the patients, and Periotest and radiographic examinations were performed. After the first year of loading, the implant outcome was again evaluated clinically and radiographically using the Periotest analysis. Crestal bone loss and Periotest values (PTVs) were used to evaluate the effect of surgery, prosthesis, implant, and a host-related factor. A general linear model was used to statistically detect variables statistically associated with crestal bone loss and Periotest value. Results: We followed up on the implants over 1 to 4 years after loading; their survival rate was 100 %, and pronounced differences from PTVs were noted among jaw location, bone quality, and loading period. No difference was detected in bone loss among the variables studied. Bone loss after functional loading was $0.14{\pm}0.39mm$. The stability value from the Periotest was $-3.29{\pm}0.50$. Conclusions: Within the limitations of this study, judicious use of platform-switched narrow implants with a conical connection must be considered an alternative for wide-diameter implants to restore a posterior edentulous region.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.1
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• pp.31-39
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• 2018

The collapse of the posterior occlusion destroys the normal occlusal plane and causes excessive wear reducing the vertical dimension. Reduced vertical dimension of occlusion causes not only aesthetic and functional problems but also overloading on the temporomandibular joints and abnormalities of muscle nerve system. In order to improve the collapsed occlusal relationship, it is necessary to consider the change of the vertical dimension. It is necessary to make a precise diagnosis and analysis before the treatment and to evaluate the adaption of patient to the new vertical dimension of occlusion. A patient with excessive overbite often has occlusal problems of tooth wear and tooth eruption. Considering these considerations, overall prosthodontic restoration is required to solve the problem. A patient of 68 year old man in this case who suffered major tooth wear and maxillary posterior teeth loss was treated with elevation of vertical dimension of occlusion by maxillary removable dental prosthesis and mandibular fixed prosthesis.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.246-252
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• 2014

$Br{\aa}nemark^{\prime}s$ original protocol required 4 to 6 months for implant osseointegration before placement of the definitive prosthesis. Although this approach gave very predictable results, it had certain drawbacks. The main disadvantages of this approach were prolonged treatment time, two surgical procedures, placement of a removable prosthesis that required modifications during the course of treatment, and a greater number of appointments. Immediate implant loading is a viable treatment method for selected cases. One of the greatest advantages of this method is the virtual surgery, which precedes the actual clinical treatment and eliminates any need for last minute decisions. The actual surgery time is decreased, since all steps are predetermined. These advantages aren't only more useful for normal patients but also for the mental retardation patients whose cooperation is difficult. This article presents a clinical approach made possible due to the guided implant surgery and CAD/CAM technique.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.79-87
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• 2021

The digital workflow of optical impressions by the intraoral scanner and CADCAM manufacture of dental prostheses is actively developing. The complex process of traditional impression taking, definite cast fabrication, wax pattern making, and casting has been shortened, and the number of patient's visits can also be reduced. Advances in intraoral scanner technology have increased the precision and accuracy of optical impression, and its indication is progressively widened toward the long span fixed dental prosthesis. This case report describes the long span implant case, and the operator fully utilized digital workflow such as computer-guided implant surgical template and CAD-CAM produced restoration after the digital impression. The provisional restoration and customized abutments were prepared with the optical impression taken on the same day of implant surgery. Moreover, the final prosthesis was fabricated with the digital scan while utilizing the same customized abutment from the provisional restoration. During the data acquisition step, stl data of customized abutments, previously scanned at the time of provisional restoration delivery, were imported and automatically aligned with digital impression data using an 'A.I. abutment matching algorithm' the intraoral scanner software. By using this algorithm, it was possible to obtain the subgingival margin without the gingival retraction or abutment removal. Using the digital intraoral scanner's advanced functions, the operator could shorten the total treatment time. So that both the patient and the clinician could experience convenient and effective treatment, and it was possible to manufacture a prosthesis with predictability.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.2
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• pp.150-156
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• 2015

As dental implant treatment becomes popular for both partial and complete edentulous patients, old people with complex systemic diseases also tend to prefer implant-assisted-overdenture or implant-supported-fixed prostheses to conventional complete denture. In this case, 77-year-old female who was on medication for hypertension and osteoporosis and paralyzed on right side due to stroke visited for implant-assisted-overdenture on lower jaw. After oral and radiographic examination, root-assisted magnet overdenture on upper jaw and implant-assisted magnet overdenture on lower jaw are planned. Consequently, overdentures using self-adjusting magnetic attachment(SA) system on both jaws resulted in recovering satisfying function and retention, which is enable to insert and remove with only one hand.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.417-423
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• 2014

The aim of this study was to evaluate the relationship between prosthetic status and health related quality of elderly by using EuroQol-5 dimension (EQ-5D) which is a standardized instrument used as a measure of health outcome. Data from 1,179 elderly subjects (over 65 years old) from the fifth Korea National Health and Nutrition Examination Survey were used in our analysis. Oral examination were conducted to obtain wearing prosthetic and needed prosthetic. EQ-5D is a widely used health condition measuring instrument. It consists of the five dimensions: Mobility, Self-care, Usual activities, Pain/discomfort and Anxiety/depression. EQ-5D index is a score calculated out of a weighting system. In this study, the mean score of the EQ-5D index among the elderly was 0.86. For EQ-5D index gender, female showed statistically significantly lower quality of life than male. The related factors EQ-5D index, when the lower demand for fixed prosthodontics and full denture. Wearers in partial and complete denture than non-wearers showed higher EQ-5D index. In order to improve EQ-5D index among the elderly who demand prosthetic status, which has lost its function through providing proper dental prostheses.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.123-130
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• 2024

There are various methods for restoring the dentition of completely edentulous patients. Removable complete dentures have the advantage of being relatively economical, but they can be uncomfortable to wear. With the introduction of implant prosthodontics, various options such as implant-supported overdentures and hybrid prostheses have become available. If there is inadequate remaining ridge or limited financial resources, an overdenture supported by a few implants with additional attachments may be more suitable. In this case, due to severe peri-implantitis and other complications, the implants were removed. Subsequently, four implants (two on each side) were placed in the maxilla and a milled-bar with attachment was fabricated for each side of the maxilla.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.455-469
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• 2008

Statement of problems: In the area of dental care, the institutionalized elderly have placed the most vulnerable state, and we cannot find their subjective need of dental treatment because of the physical and mental disabilities, But we have no basic investigation of their oral health conditions. Purpose: The aims of the current study were to investigate the oral health status of institutionalized elderly patients who are in the least benefited side of dental service, and to analyze their dental treatment needs. Material and methods: The survey of the oral status was carried out on 758 institutionalized elderly, and 212 elderly who was more than 65 years old from D dental office, and it was based on the Guidelines of Oral Health Research of year 2000 in Republic of Korea. Results and conclusion: The DMFT index of the institutionalized elderly appeared higher than that of the same ages in control group, and it increased with age. The number of residual teeth of the institutionalized elderly appeared lower than that of the same ages in control group, and it decreased with age (P < .05). The number of fixed partial denture in institutionalized elderly was lower than that of the same ages in control group (P < .05). The percentage wearing removable partial denture was not significant between the elderly in institutions and the control group, and was not different according to age between the two groups. The percentage of institutionalized elderly wearing complete denture appeared lower than that of the same ages in control group, and it increased with age. The percentage of institutionalized elderly needing complete denture was higher than that of control group, and the percentage of elderly needing complete denture on the maxilla was higher than that of the mandible. 16.35% of the institutionalized elderly was living without denture in spite of their fully edentulous state. The need for complete denture increased rapidly with age. The number of valued teeth and dental prostheses in shortened dental arch concept and number of occluding pairs of teeth of institutionalized elderly were lower than that of the control group (P < .05). In institutionalized elderly, the number of residual teeth, the number of fixed partial dentures, and the percentage wearing removable partial dentures were higher in the mandible, and the percentage wearing complete dentures was higher in the maxilla (P < .05). The rate of institutionalized elderly needing prosthodontic treatment appeared to be 67.82%, where the number of occluding pairs of teeth was less than 10. When it is difficult to evaluate the subjective need of dental treatment as with the institutionalized elderly, estimation using the number of occluding pairs of teeth can be a useful indicator that can project treatment needs. For the oral health care of institutionalized elderly, it is essential to increase the awareness of nurses and caregivers who take care of them, about the importance of the oral health. Since the average life span and number of residual teeth are increasing gradually, the welfare policy should be changed to implementing regular dental examinations, preservative treatment forms and oral health control of dentulous patients where the traveling-treatment system and visit system are supplemented. And principles should be set that the present denture project of edentulous patients should be done by specialists who'll also be responsible for postmanagement. Through this research of institutionalized elderly, the oral health status which is worsened by aging could be confirmed. And the interest and positive participation of dental society on the elderly should come first in order to solve the rising treatment needs of the elderly patients.