• The korean journal of orthodontics
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• v.51 no.2
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• pp.135-141
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• 2021

Objective: To assess the effects of thermoforming on aligner thickness and gap width in six aligner systems with the same nominal thickness. Methods: Six passive upper aligners of different brands were adapted to a single printed cast. Each sample was evaluated with high-resolution micro-computed tomography. To investigate aligner thickness and gap width, two-dimensional (2D) analysis was conducted assessing the effects of the following variables: tooth type (central incisor, canine, and first molar), 2D reference points, and aligner type. Data were analyzed and compared using analysis of variance and Tukey's post-hoc tests (p < 0.05). Results: Tooth type, dental region, and aligner type affected both the gap width and aligner thickness. The aligner thickness remained moderately stable across the arch only in the F22. Conclusions: All thermoformed samples displayed smaller aligner thickness and gap width at anterior teeth and both gingival and coronal centers than at posterior teeth and occlusal surfaces.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.551-562
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• 2016

There are interferences between the teeth to be moved and the clear aligner made from setup. These interferences generate forces which move teeth to the desired position. However, these can cause incomplete tooth capture of clear aligner. When these interferences exceed the acceptable deformation of aligner, unwanted intrusion of teeth to be moved occurs. When correction of rotation or tipping of teeth is attempted, intrusion prevails before rotation or tipping. However, clear aligner can induce labiolingual tipping or intrusion easily. To achieve preliminary alignment including control of rotation and tipping, NiTi archwires with fixed appliance can be used first, and then clear aligner can be used for finishing in mild Class I maloccusion cases. For this purpose, clear aligner can be made using a digital setup and 3D printing. To move teeth using a clear aligner, tooth capture is critical. To improve tooth capture of clear aligners, slingshot or vertical elastics can be used. These were discussed with illustrations.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.30 no.1
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• pp.13-23
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• 2021

These days, Clear aligners occupy an important position in dentistry, and have increased in popularity and in the market share of orthodontic treatment system. Currently, the world's No. 1 company occupies a significant portion of the global clear aligner market, and many latecomers are trying to follow. Serafin clear aligner system, which is one of domestic clear aligner systems pursues comprehensive orthodontic treatment, not just target tooth movement. Here I report two orthodontic treatment cases using Serafin clear aligner system.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.981-986
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• 1993

A fast algorithm based upon geometry to measure the wafer center and the position of a wafer fiducial mark is developed and implemented on a single-axis aligner. Design issues for a controller when a National Semiconductor's LM629 is used as a PID controller of an aligner are discussed. Performance of an aligner with the algorithm and a LM629 was measured in experiments. The result shows that it takes about 4.1 seconds on average to align a hot wafer supported by metal pins on the chuck.

• Journal of the Semiconductor & Display Technology
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• v.16 no.1
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• pp.29-33
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• 2017

This paper presents a development of vision aligner with three channels for the wafer and plate bonding machine in manufacturing of LED. The developed vision aligner consists of three cameras and performs wafer alignment of rotation and translation, flipped wafer detection, and UV Tape detection on the target wafer and plate. Normally the process step of wafer bonding is not defined by standards in semiconductor's manufacturing which steps are used depends on the wafer types so, a lot of processing steps has many unexpected problems by the workers and environment of manufacturing such as the above mentioned. For the mass production, the machine operation related to production time and worker's safety so the operation process should be operated at one time with considering of unexpected problem. The developed system solved the 4 kinds of unexpected problems and it will apply on the massproduction environment.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.923-928
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• 2004

AFM tip has been used for surface profiling with a fine resolution, but there is a barrier to improve its performance because of the low aspect ratio. Many researchers have solved this problem with attaching carbon nanotube (CNT) to Si-tip. In this paper, we proposed the aligner system that composed of dual type stage system, and these stages could attach a carbon nanotube to tungsten-tip in vacuum condition. We used tungsten tip instead of Si-tip because of its conductivity. The aligner system proposed in this paper has 10 degree-of-freedom that 3 in the first stage and 7 in the second stage. With picomotors and piezotube, the first stage has the resolution about several tens of nm and the second stage has a resolution about a nm. We experimented on characterization of Nano Aligner System and operated picomotors in SEM environment.

• Journal of Korean society of Dental Hygiene
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• v.14 no.4
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• pp.539-545
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• 2014

Objectives : The purpose of the study is to investigate the knowledge and self care behaviors of orthodontic patients using clear aligner. Methods : A total of 181 orthodontic patients using clear aligner in Daegu filled out the self-reported questionnaire from September 6 to October 18, 2010. and 162 subjects completed orthodontic treatment. Results : There existed a significant difference in knowledge and self care behaviors between gender and wearing duration of clear aligner(p<0.01). Treatment duration influenced significantly on the score of self care behaviors(p<0.01) and the high score of self care behavior showed in short duration of treatment. Conclusions : Self care behaviors were closely correlated with treatment duration. An information for the clear aligner will be helpful to improve the knowledge and self care behaviors.

• Journal of Periodontal and Implant Science
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• v.41 no.1
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• pp.44-50
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• 2011

Purpose: Pathologic tooth migration (PTM) is a tooth displacement which is derived from imbalance of tooth retention force and is dominantly found out in maxillary anterior area. PTM in maxillary anterior area was tried to corrected with periodontal treatment and a clear aligner in this study and the result was evaluated clinically and radiographically. Methods: For the treatment of a patient with chronic periodontal disease accompanied by maxillary anterior pathologic tooth migration, clear aligner was applied to move teeth after a series of case-related periodontal therapy. Clinically, probing depth, gingival recession, clinical attachment level and mobility were measured pre- and post-treatment, and radiographic examination was performed as well. Results: Clinically, we found the decrease of the probing depth, gingival recession, clinical attachment level and mobility. And we could also acknowledge the reduction of vertical and horizontal dimension on infrabony defect radiographically. However, it is still controversial if there was an actual bone filling. Conclusions: Clear aligner is an effective appliance to move teeth since it costs little in terms of expense and time. In addition, it wraps whole crowns, providing advantages to deal with crowding, spacing, and size of arch. In short, clear aligner could be a useful treatment option for PTM patient, since it provides decreased probing depth, gingival recession, clinical attachment level, mobility and esthetical restoration.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2553-2556
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• 2003

In the semiconductor equipment industry, the SECS/GEM protocol has been recognized as the communication standard, but in our 300mm wafer aligner being developed, this capability has not been equipped yet. In this study, we present the realization of SECS-I, SECS-II and HSMS communication protocol between factory host computer and wafer aligner. Its validity is shown in actual test environment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.13-14
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• 2008