• The Journal of Korean Academy of Prosthodontics
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• v.61 no.3
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• pp.245-256
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• 2023

When restoring with a dental digital system for implant-supported prosthesis, a double digital scanning technique is required: an intraoral scan of the three-dimensional implant location and intraoral scan after placement of temporary denture or provisional prosthesis. During the intraoral scan, the use of scan body as a stable landmark can improve the accuracy of digital impression and simplify laboratory process. In this case, a full-digital system was used to plan and fabricate a custom abutment, provisional prosthesis, and definitive prosthesis. After implant placement, the scan area of the intraoral scan body connected with implant and the intraoral scan body marked on the inside of temporary denture were superimposed. Out of the superimposed files, a custom abutment and provisional prosthesis were fabricated which match the vertical dimension of temporary denture, and definitive prosthesis was fabricated based on provisional prosthesis. We report this case because result has been functionally and esthetically satisfactory by using vertical dimension and central relation set during the fabrication of temporary denture to the definitive prosthesis.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.39-46
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• 2013

The loss of posterior support may cause attrition of anterior teeth, and loss of occlusal vertical dimension (OVD). The collapse of the posterior support will eventually cause the pathologic change of the TMJ and masticatory muscles, unesthetic facial appearance and decreased masticatory function. Patients with destroyed dentition need extensive prosthetic treatments. Proper diagnosis and treatment planning are necessary for the stability of the neuromuscular system and the TMJ, and esthetic and functional definitive restorations. In this case, 63 year-old male presented with decreased masticatory force and esthetic problems due to pathologic destruction of teeth structure on entire dentition. Based on assessment of OVD including intraoral findings, radiographic examination and diagnostic cast, full-mouth rehabilitation with increase of OVD was planned using fixed partial denture and removable partial denture. Diagnostic wax-up was done after 4 mm increase of OVD determined by assessment of OVD. The OVD was maintained with the overlay type removable interim prostheses for 12 weeks to ascertain his comfort and adaptation to the new OVD. After the adaptation period, second interim prostheses with tooth preparation maintaining the established OVD was delivered. After 4 weeks, final prostheses were fabricated and delivered. After 7 month follow-up period, occlusal stability is maintained. Through this procedure, satisfactory outcomes were achieved both in functional and esthetic aspects.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.365-375
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• 2009

Statement of problems: Stress analysis on implant components of the combined screw- and cement-retained implant prosthesis has not investigated yet. Purpose: The purpose of this study was to assess the load distribution characteristics of implant prostheses with the different prosthodontic retention types, such as cement-type, screw-type and combined type by using 3-dimensional finite element analysis. Material and methods: A 3-dimensional finite element model was created in which two SS II implants (Osstem Co. Ltd.) were placed in the areas of the first premolar and the first molar in the mandible, and three-unit fixed partial dentures with four different retention types were fabricated on the two SS II implants. Model 1 was a cement-retained implant restoration made on two cement-retained type abutments (Comocta abutment; Osstem Co. Ltd.), and Model 2 was a screw-retained implant restoration made on the screw-retained type abutments (Octa abutment; Osstem Co. Ltd.). Model 3 was a combined type implant restoration made on the cement-retained type abutment (Comocta abutment) for the first molar and the screw-retained type abutment (Octa abutment) for the first premolar. Lastly, Model 4 was a combined type implant restoration made on the screw-retained type abutment (Octa abutment) for the first molar and the cement-retained type abutment (Comocta abutment) for the first premolar. Average masticatory force was applied on the central fossa in a vertical direction, and on the buccal cusp in a vertical and oblique direction for each model. Von-Mises stress patterns on alveolar bone, implant body, abutment, abutment screw, and prosthetic screw around implant prostheses were evaluated through 3-dimensional finite element analysis. Results: Model 2 showed the lowest von Mises stress. In all models, the von Mises stress distribution of cortical bone, cancellous bone and implant body showed the similar pattern. Regardless of loading conditions and type of abutment system, the stress of bone was concentrated on the cortical bone. The von-Mises stress on abutment, abutment screw, and prosthetic screw showed the lower values for the screw-retained type abutment than for the cement-retained type abutment regardless of the model type. There was little reciprocal effect of the abutment system between the molar and the premolar position. For all models, buccal cusp oblique loading caused the largest stress, followed by buccal cusp vertical loading and center vertical loading. Conclusion: Within the limitation of the FEA study, the combined type implant prosthesis did not demonstrate more stress around implant components than the cement type implant prosthesis. Under the assumption of ideal passive fit, the screw-type implant prosthesis showed the east stress around implant components.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.306-313
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• 2013

Speech is complex psycho-physiological mutual process which includes many orofacial organs. Especially, teeth play an especially important role as an articulation organ in conjunction with the lips and tongue. When teeth are missing, the position of tongue and mandible is adjusted to produce correct sound. If a patient's adaptive function is inadequate for modification of malocclusion, prosthodontic and orthodontic interventions are necessary. Missing teeth of young patients should be reconstructed bacause it can cause malocclusion, decreased masticatory efficiency, articulation disorders, esthetic problem, and temporomandibular disorder. Valplast$^{(R)}$(Valplast International Corp, New York, USA) flexible denture is useful for rehabilitation due to its excellent physical properties, esthetics, and small volume. This case is regardingan intellecturally disabled patient with anarticulation disorder caused by missing lower incisors due to trauma. The patient showed improvement in articulation by using flexible partial denture. The purpose of this report is to figure out the influence of missing lower anterior teeth on articulation.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.1
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• pp.127-134
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• 2022

Among many contributing factors of implant failure, excessive loading and inflammation contribute mainly to increasing implant failure rate. Especially, poor oral hygiene around implants is one of the most common reasons for implant failure. When implant prosthesis fails to function, the clinician should re-diagnose and plan treatment using the remaining implants. Additional implantation may be needed to make a new type of prosthesis or either implant-assisted RPD and implant overdenture treatment may be performed using the remaining implants. In this article, a patient whose fixed implant prosthesis in the maxilla had failed of poor oral hygiene maintenance was reported to be recovered with removable implant overdenture by using remaining implant abutments and a milled bar with additional retentive elements. Through this treatment, the clinical results were satisfactory in terms of esthetics, masticatory function recovery and oral hygiene management.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.178-188
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• 2022

Interim immediate denture is fabricated to minimize the period of edentulousness after removal of the patient's remaining teeth and before delivery of final prosthesis. In the case of using the CAD/CAM system, there is an advantage in that the manufacturing process in the clinic and laboratory can be simplified by overcoming some of the limitations of manufacturing interim immediate dentures in the traditional way. However, there are also disadvantages in that errors occur in the process of transmitting information about the patient's intermaxillary relationship to the digital network of the laboratory, resulting in unstable occlusal relationships or non-esthetic prostheses. To overcome this problem, using the simple and accurate POP BOW system's occlusal plane digital transfer method, it was possible to fabricate an esthetic and functional 3D printed interim immediate denture after removal of the remaining upper and lower anterior teeth.

• The Journal of Korean Academy of Prosthodontics
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• v.8 no.1
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• pp.20-24
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• 1968

Recognition thresholds for representatives of the salt, sweet, bitter, and sour modalities of taste were determined in 25 patients with dentures. The following results were obtained. (1) Recognition thresholds for the taste of NaCl(salt) and Sucrose(sweet) were essentially unchanged with or without the dentures in place. (2) Recognition thresholds for HCl(sour) and Urea(bitter) increased after the patients inserted their dentures. The amount of increase was 59.4% and 112.5% for HCl and Urea, respectively. (3) Recognition thresholds for all four taste modalities inpatients with ill-fitting dentures were not significantly changed with or without dentures in place. (4) Recogniton thresholds for all four taste modalities in Korean were greater than those of Pfaffamann's.

• The Journal of Korean Academy of Prosthodontics
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• v.8 no.1
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• pp.77-79
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• 1968

The swallowing threshold tests were conducted on the 8 subjects over one month of full denture wearing experience of Korean. The results were follows. 1) The swallowing threshold of the full denture wearer was higher than that of the normal control group. 2) The swallowing threshold of the full denture wearer was different according to the quality and quantity of the test food. 3) The swallowing threshold of full denture wearer seemed to be no correlation between short and long duration of wearing experience.

• The Journal of the Korean dental association
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• v.12 no.2
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• pp.131-134
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• 1974

The author had studied the masticatory effience on three different types; on missing of the first molar, on replacing the missed first molar with crown & bridge and on natural dentition. This study was made from the parched soybeans as testfood by means of mesh technique. As a result of this study on 25 of natural dentitions, 20 of crown & bridges and 25 of missing of the first molars, the following were come out. 1. Masticatory efficiency of natural dentitions was 75.8%, that of crown & bridges was 66.4%, and that of missing of the first molars was 43.7%. 2. Difference of masticatory efficiency of crown & bridges to natural dentitions was 9.4%, that of natural dentitions to missing teeth was 32.1%, and that of crown & bridges to missing teeth was 22.7%.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2033-2035
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• 2001

본 연구는 기존의 자전거에 전기 구동장치를 장착시켜서 자전거의 페달링에 의하여 검출된 답력을 이용한 보조 동력 구동장치에 대한 개발이다. 답력의 검출은 불시의치차를 이용한 동력 전달장치를 이용하였다. 이 장치의 입력기어에서 출력기어로 동력을 전달하는 아이들 피니언 기어와 결합된 캐리어를 동력 전달시 발생하는 반력에 의한 각도를 이용하여 토크량을 측정하였다. 동력전달을 할 경우 발생하는 반력에 의한 회전각을 자기센서를 이용하여 답력을 측정하였다. 이 답력을 구동회로에 인가하여 보조동력을 자전거에 인가함에 따라 주행을 쾌적하게 하도록 개발하였으며 실험을 통하여 실용성을 고찰하였다.