• 한국치위생학회지
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• 제16권4호
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• pp.635-641
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• 2016

Objectives: The purpose of this study is to assess the characteristics of tooth surface after using Gracy curet and Ultrasonic scaler Methods: In this study, 12 teeth extracted were used. 12 specimens were divided into three groups with the same numbers, which were classified into Control group, Gracy curet use group, and Ultrasonic scaler use group, and after performing instrument operation, we measured the roughness and the loss degree of tooth surface by using SEM. Results: In groups using Gracy curet and Ultrasonic scaler, the roughness and the loss of tooth surface increased significantly(p<0.05). In the roughness of groups using Gracy curet and Ultrasonic scaler, Ultrasonic scaler group was higher in crown, but Gracy curet group was higher in root. As a result of observation through SEM, the roughness and the loss degree increased in order of Control group, Ultrasonic scaler use group, and Gracy curet use group. Conclusions: Taken together above results, both hand instrument and ultrasound equipment create roughness and loss in crown and in root, and hand instruments makes rougher than ultrasonic instruments in root, so it is thought to require thorough and accurate technical application not to damage tooth surface when removing plaque.

• Restorative Dentistry and Endodontics
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• 제13권1호
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• pp.181-184
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• 1988

The purpose of this study was to evaluate the efficacy and safety of ultrasonic root canal preparation technique. 55 patients treated by each of the two techniques - ultrasonic and, hand - were evaluated the complications of two root canal preparation techniques. The results were as follows: 1. There was no difference in the pain incidence between the two groups. 2. There was no formation of performation and ledge in the ultrasonic group. 3. There was no difference in the shortening of working length between the two groups.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.113-115
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• 2005

To explore the seafloor, an observation instrument should be laid there for a long time and it should be again withdrawn. This system must be designed low power consumption model because it operates for a long period, but because power control don't execute or simply control algorithm executes, power efficiency is low. Hereupon, a power control algorithm for retrieval system using the ultrasonic communication that was improved its controllability and movability was presented in this paper. Likewise, the logicality of control algorithm and remote control system were ascertained by experiments.

• Journal of Periodontal and Implant Science
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• 제31권3호
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• pp.531-542
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• 2001

Periodontal debridement is most important procedure in periodontal treatment, because periodontal disease is the biofilm infection. The use of ultrasonic instrument has many clinical advantages compared to classical hand instrument. The introduction of newly developed ultrasonic scaler tips made the use of ultrasonic scaler popular. However the study of tooth substance removal according to the working parameters of ultrasonic scaler with newly developed tips is not sufficient. The purpose of this study is to evaluate the effects of working parameters of piezoelectric ultrasonic scaler with curette tip on casting gold removal. The working parameters was standardized by the sledge device which controls lateral force(0.5 N, 1.0 N, 2.0 N) and power setting was adjusted 2, 4, 8 in P mode and S mode and instrumentation time was 5 seconds. The defect depth and width were measured with profile meter and defect surface was examined by SME. The depth of defect was significantly large in S mode( $39.58{\pm}19.35{\mu}m$) compared to P mode( $8.37{\pm}6.98{\mu}m$). There was significant decrease of depth of defect between 1.0N($32.87{\pm}27.18{\mu}m$) and 2.0N( $14.86{\pm}15.04{\mu}m$). The area of defect was also significantly large in S mode($4482.42{\pm}3551.71{\mu}m^2$) compared to P mode( $922.06{\pm}960.32{\mu}m^2$). There was significant decrease of area of defect between 1.0N($3889.12{\pm}3936.00{\mu}m$) and 2.0N( $974.66{\pm}986.01{\mu}m$). The change of mode did not effect on the width of the defect. The change of power setting did not effect on the depth, width, and area of defect. In spite of limitation of this study it could be concluded that the use of piezoelectric ultrasonic scaler with curette tip on S mode could make significant tooth substance loss.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.9-13
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• 2001

This paper proposes the electric stimulus tactile apparatus system(TESTAS) loaded on the hap-tic interface using ultrasonic motors(USMs). To touch the virtual object like wall in graphic, the 6 DOF haptic interface provides force feedback to users as if it is real. But the case of sharp virtual object like a puncture, it could not provided the sense of pain, but only the reaction-force. After the TESTAS had been loaded on this haptic interface. it could Provide not only the force but also the pain to users. To estimate the capability of TESTAS, we did experiments of three cases, one was very sharp, another was dull, the other is continuative contact.

• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.767-775
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• 2008

Methods used for exploring marine resources and spaces include positioning a probe under water and then recalling it after a specified time. Hydro-acoustic Releasers are commonly used for positioning and retrieving of such exploration equipment. The most important factor in this kind of system is the reliability for recalling the instruments. The frequently used ultrasonic signal detection method can detect ultrasonic signals using a fixed comparator, but because of increased rates of errors due to outside interferences, information is repetitively acquired. This study presents an effective ultrasonic signal detection algorithm using the characteristics of a resonance and adaptive comparator Combined with the FSK+ASK modulator. As a result, approximately 8.8% of ultrasonic wave communication errors caused by background noise and transmission losses were reduced for effectively detecting ultrasonic waves. Furthermore, the resonance circuit's quality factor was enhanced (Q = 120 to 160). As such, the bias voltage of the transistor (Vb= 3.3 to 6.8V) was increased thereby enhancing the frequency's selectivity.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1209-1213
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• 1991

This paper describes a new method for performance improvement ultrasonic ranging system using V40 controller. Detectable range of ultrasonic ranging system depends on transducer frequency and bandwidth of the receiver, and damping of the transducer, etc. Conventional ranging systems are somewhat inaccurate because they do not have capability of compensating changes in medium condition. The novel ranging system overcomes this disadvantage by placing in the same medium a dummy sensor functioning as a standard calibrating instrument and by providing data processing capability using V40 controller.

• 한국컴퓨터정보학회논문지
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• 제7권1호
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• pp.80-87
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• 2002

본 논문에서는 초음파를 이용한 동력을 활용하는 기기에 필요한 자동 주파수 추적 장치를 연구하고, 이를 개발하는 데 있다. 지금까지의 초음파 자동 주파수 추적은 아날로그 방식으로 이루어져 있으며 보다 정밀한 제어를 필요로 하는 분야에는 이 방식의 한계를 극복할 수 있는 새로운 방식의 추적장치를 필요로 한다.

• 대한의용생체공학회:의공학회지
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• 제44권2호
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• pp.109-117
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• 2023

In this study, the effect of the shape of the specimen and the feedrate of the dental ultrasonic surgical instrument on the cutting force and surface roughness of the specimen is analyzed. Experimental specimens were made of SAWBONES artificial bone materials in square and spherical specimens. In addition, the cutting feedrate of the surgical instrument was controlled through the developed moving system. The cutting force generated when cutting the specimen was measured through a force sensor. After the experiment, the cutting surface of the specimen was observed through a three-dimensional optical microscope and the surface roughness was measured. Through one-way ANOVA, the effect of each specimen shape and feed rate on surface roughness was analyzed. As a result of the experiment, the cutting force increased proportionally in the initial feed rate increase stage, but the increase in cutting force decreased as the feed rate continued to increase. Also, the cutting force showed a difference according to the shape of the specimen. The spherical specimen with a relatively small cutting surface area had less cutting force than the square specimen. However, as a result of one-way ANOVA, it was found that the specimen shape and feed rate did not affect the surface roughness. In future studies, it is expected to be used for comparative analysis of ultrasonic surgical instruments and correlation analysis between cutting factors.

• Restorative Dentistry and Endodontics
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• 제45권2호
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• pp.14.1-14.7
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• 2020

Objective: The aim of this study was to perform a comparative evaluation of the effectiveness of ultrasonic tips versus the Terauchi file retrieval kit (TFRK) for the removal of broken endodontic instruments. Materials and Methods: A total of 80 extracted human first mandibular molars with moderate root canal curvature were selected. Following access cavity preparation canal patency was established with a size 10/15 K-file in the mesiobuccal canals of all teeth. The teeth were divided into 2 groups of 40 teeth each: the P group (ProUltra tips) and the T group (TFRK). Each group was further subdivided into 2 smaller groups of 20 teeth each according to whether ProTaper F1 rotary instruments were fractured in either the coronal third (C constituting the PC and TC groups) or the middle third (M constituting the PM and TM groups). Instrument retrieval was performed using either ProUltra tips or the TFRK. Results: The overall success rate at removing the separated instrument was 90% in group P and 95% in group T (p > 0.05) The mean time for instrument removal was higher with the ultrasonic tips than with the TFRK (p > 0.05). Conclusion: Both systems are acceptable clinical tools for instrument retrieval but the loop device in the TFRK requires slightly more dexterity than is needed for the ProUltra tips.