• The korean journal of orthodontics
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• v.47 no.3
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• pp.207-212
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• 2017

The popularity of clear overlay retainers (CORs) has increased recently because of their advantages such as better esthetics, cost effectiveness, easy fabrication, and good compliance. However, a deficiency in posterior occlusal settling is a reported limitation of CORs. The aim of this study was to evaluate the posterior occlusal contact changes in a new type of clear orthodontic retainer called Oral-treaper (OTP), which consists of three layers and has stronger mechanical characteristics than do conventional retainers. Three patients who completed fixed orthodontic treatment received OTP as a removable retainer. Cast models were fabricated after the removal of fixed appliances (T1) and after 4 to 11 months of using the retainers (T2). We evaluated all the cast models to compare the post-orthodontic settling pattern during the use of the OTPs. The depth of occlusal contacts was evaluated using color maps. The OTP did not prevent vertical settling in all patients but resulted in an improvement in posterior occlusal contact points.

• The Journal of the Korean dental association
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• v.58 no.8
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• pp.496-504
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• 2020

The osseointegrated implants react biomechanically in a different pattern to occlusal force, due to lack of the periodontal ligament unlike the natural teeth. The implants show markedly less movement and limited tactile sensitivity compared with the natural teeth. The implant occlusion concept aims to avoid overloading on the implants and to direct occlusal loads along the longitudinal axis of the implants, in order to compensate for the different biomechanics of the implants. Although many guidelines and theories on implant occlusion have been proposed, few have provided strong supportive evidence. Moreover, the outcome of treatment often quite successful in spite of different concepts of occlusion and there is an increasing tendency to doubt about the strict theoretical implant-specific occlusion concept. The purpose of this article is to review the previous reports about the concept of implant occlusion and discuss clinical occlusal considerations in implant rehabilitations.

• The korean journal of orthodontics
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• v.33 no.5 s.100
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• pp.391-398
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• 2003

Distraction osteogenesis is a well-estabilished procedure of membraneous bone formation and has been used to correct craniofacial deformities in dentofacial orthopedic-surgery area for decades. In this articale, distraction osteogenesis is used for treatment of facial asymmetry. The patient underwent procedures to lengthen the mandibular ramus and body. After distraction, orthodontic treatment was done for ooclusal settling.

• Journal of Technologic Dentistry
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• v.30 no.2
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• pp.47-56
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• 2008

This is a research for thickness change of denture base according to the shape of sprue & investment position of denture base in flask when injecting polyamid base resin for flexible partial denture as a part of study for Valplast among the flexible partial denture with a nylon base. It has been introduced several kinds of flexible partial denture product with a nylon base, but Valplast is the most widely used product among them. Valplast has been the most generally used material today since developed in 1950s in the United States as a material for flexible partial denture. Valplast is much more aesthetic than general metal-acrylic partial denture due to its translucent pink color and biocompatibility in terms of material characteristic. It keeps its flexibility for a long time after production, imposes a less burden on the teeth used as abutment, and it can be easily insert and remove due to its particular suppleness. Moreover, it is felt like real teeth more than metal-acrylic partial denture when being put in and takes alveolar bone under good protection since it receives occlusal force equally under the denture base. The most outstanding feature of Valplast is flexibility. The extent of its flexibility is determined by width & thickness of denture base. Considering general working procedure of Valplast, it can be seen that the thickness of denture base formed out of wax is increasing by the pressure while injecting resin. This research is to decide and test on the thickness increasing of Valplast by injecting pressure and the hypothesis upon that and is to prepare the basis estimating the increasing extent of thickness of denture base on the basis of the test result. In this test, it is expected occlusal malposition & thickness increasing of denture base by injecting pressure according to 4 kinds of test data which are to select 3 types of sprue method settling the forefront position at which the test material of fixed standard can be invested and to position the test material at the rearmost part keeping the minimum distance to set sprue. For 4 kinds of injecting test by investment position & sprue type, 20 test materials, 5 for each test were produced and a pressure of 1,180Kg was given with automatic injector of air cylinder type. The results are as follows: 1. For the amount of thickness increasing of denture base by investment position, the thickness of front investment is less increasing than the one of rear investment. 2. For the amount of thickness increasing of denture base by sprue type, the thickness of straight decompression sprue type which can absorb the injecting pressure after injecting polyamide base resin is less increasing than the other sprue types.