• Title/Summary/Keyword: whitening

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Development of a Piezoelectric Ultrasonic Tooth-whitening Apparatus

  • Lee, Young-Jin;Paik, Jong-Hoo;Lee, Jeong-Bae;Choi, Seung-Jae
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.5
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    • pp.268-272
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    • 2013
  • The aim of this study was to develop an ultrasonic tooth-whitening apparatus using piezoelectric transducers, which enhance bleaching efficiency by applying ultrasound, while performing a teeth whitening procedure. For this purpose, an ultrasonic transducer was designed and manufactured, and the effects of reduction in the whitening material's concentration and in the whitening treatment time through using the ultrasound cavitation phenomenon were confirmed. Also, the validity of this study was investigated by comparing the whitening performance with a commercialized optical whitener, through color comparison. The results revealed that the ultrasound whitener produced color values that were enhanced by as much as double that of the conventional LED light whitening method. Even when the operational time was reduced by half, the ultrasound method showed superior performance by over 54% compared to the conventional light whitener, revealing that the ultrasound method showed a remarkable treatment reduction effect.

Evaluation of Skin Sensitization Potential of Skin Whitening Agents by Local Lymph Node Assay (국소 림프절 시험법(Local lymph node assay)을 이용한 피부미백화장품 원료의 피부감작성 연구)

  • 이종권;박승희;박재현;김형수;엄준호;남기택;한범석;장동덕;최광식
    • Toxicological Research
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    • v.19 no.4
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    • pp.285-291
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    • 2003
  • The use of skin whitening agents has been recently increased in various kinds of cosmetic products, although there were some reports that whitening agents might cause allergic contact dermatitis. A murine local lymph node assay (LLNA) has been developed as an alternative to guinea pigs for contact sensitization potential. This study was carried out to investigate the skin sensitization potential of three whitening agents, arbutin, azelaic acid, and kojic acid, by LLNA using a non-radiois-topic endpoint. Female Balb/c mice were exposed topically to a weak allergen, $\alpha$-hexylcinnamalde-hyde (HCA), and three whitening agents following LLNA protocol. Lymph node (LN) weight and cell proliferation in ears and auricular lymph node using bromodeoxyuridine (BrdU) immunohistochemistry were evaluated. LN weights were significantly increased at the HCA group compared to the vehicle control. A weak allergen, HCA elicited 3-fold or greater increase in cell proliferation of lymph nodes as well as increase in cell proliferation of ear as measured by BrdU immunohistochemistry. However, in the case of skin whitening agent groups, there were no significant changes in LN weight and cell proliferation in the ear and lymph node of mice treated with 5, 10 and 20% of three whitening agents compared to the vehicle control. These results show that these three skin whitening agents may not have contact sensitization potentials at tested concentrations in Balb/c mice by LLNA.

Study on the Improvement of Milling Recovery and Performance (IV) -Rice Whitening Performance of the Combined Abrasive- and Friction-type Whiteners- (도정수율(搗精收率)과 성능향상(性能向上)을 위(爲)한 연구(硏究)(IV) -연삭(硏削)·마찰(磨擦)의 조합식(組合式) 정백작용(精白作用)이 정백성능(精白性能)에 미치는 영향(影響)-)

  • Kim, Sam Do;Chung, Chang Joo;Noh, Sang Ha
    • Journal of Biosystems Engineering
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    • v.7 no.2
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    • pp.72-85
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    • 1983
  • Rice whitening is performed by basically two different whitening actions known as abrasive and frictional. The former adopted in the emery stone abrasive type whiteners and the latter in the jet-air friction type. Comparative milling yields and whitening efficiencies between the whitening system consisting of jet-air friction type whiteners only and the system consisting of both abrasive- and jet-air friction-types have not yet been rigorously defined. This study was to examine the effect of combined operations of abrasive- and jet-air friction-type rice whiteners on milling yields and whitening efficiencies. The small capacity commercial units of the abrasive- and friction-type whiteners were used for the experiments. The combinations of whitening treatments were: 1) Once in the abrasive type and then two to three times in the friction type, 2) twice in the abrasive and then two to three times in the friction type and 3) three to five times in friction type. In these tests, counter pressures for the friction type whiteners were established differently as required to get about the same degree of whitening at the end of predetermined numbers of the repeated operations. The speed of emery stone and the slot angle of the screen were also the factors varied in the abrasive type whitener. Sheukwang rice variety having 13.05% M.C. was used in the tests. The dependent variables were the milled- and head-rice recoveries and electricity consumption. The results of the study are summarized as follows: 1. It was found that in the whitening systems consisting of abrasive- and friction-type whiteners slot angle of the screen, the rotational speed of emery stone roller had significant effect on the milling yields and whitening efficiency. In general, the increase of the emery stone roller speed from 690 to 950 rpm presented a positive effect on milling yield, and one-pass abrasive milling combinations had higher milling yields than two-pass abrasive milling combinations. 2. It was apparent that if the slot angle of the screen and the speed of emery stone roller are modified and set at an optimum level, the combination whitening system consisting of abrasive- and friction-type whiteners is better than the pure frictional whitening system consisting of jet-air friction type in terms of milling yields and efficiencies. 3. In the rice whitening system consisting of abrasive- and jet-air friction-type whiteners, the best whitening performance was obtained when the slot angle of the screen and the rotational speed of emery stone roller were $45^{\circ}$ and 950rpm, respectively, for the one-pass abrasive milling combinations. However, for the two-pass abrasive mi11ing combinations, the best performance was obtained with $75^{\circ}$ of slot angle and 950 rpm of the emery stone roller speed. 4. As compared with pure frictional whitening systems, the combination systems produced more milled rice by 0.8-1.0% point and more head rice by 0.5-1.5% point, and consumed less electricity by 0.15-0.20 KwH per 100kg of milled rice when the abrasive whiteners were operated in the modified conditions as described in item 3 above. Further study is recommended to find out optimum operational and design conditions of abrasive type whiterners.

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The Comparative Evaluation of Fermented and Non-fermented Soybean Extract on Antioxidation and Whitening

  • Chae, Ga-Yeon;Ha, Bae-Jin
    • Toxicological Research
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    • v.27 no.4
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    • pp.205-209
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    • 2011
  • The present study was performed to compare the antioxidative and whitening activities of fermented soybean extract (FSB) and non-fermented soybean extract (SB). Antioxidative and whitening activities of FSB and SB were evaluated by the determination of DPPH, superoxide radical and hydroxyl radical scavenging activities, linoleic acid inhibition activity, and tyrosinase inhibition activity. FSB showed the higher effect than SB in the antioxidative activities. Also FSB showed the better effect than SB in whitening activity. These results demonstrated that the fermentation played a more excellent role than the non-fermentation in antioxidation and whitening. Therefore, this study suggested that FSB could be a useful cosmetic ingredient for antioxidation and skin whitening.

Whitening Effect with Fruit and Whitening Toothpaste (과일 및 미백치약으로 처리한 치아의 미백효과)

  • Gong, Min-Ji;Kim, Se-Won;Kim, Sol-Ji;Ahn, Hyun-Joo;Chae, Woo-Ri;Hong, Seung-Ji;Nam, Seoul-Hee
    • Journal of the Korea Convergence Society
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    • v.8 no.9
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    • pp.127-133
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    • 2017
  • The purpose of this study is to confirm the effect of natural tooth whitening using fruits that can be easily accessed in real life by increasing interest in tooth whitening in modern society. Twenty premolar teeth were divided into five groups (n=4). Strawberry (A), lemon (B), banana skin (C), baking soda (D) and whitening toothpaste (E) were treated with a toothbrush on the enamel surface. The tooth surface was treated with a toothbrush at the same time for 3 minutes for breakfast, lunch, and dinner, then washed with sterile distilled water, and stored in saline solution. This procedure was repeated for 4 weeks, and the color change of teeth was observed at intervals of one week. After 4 weeks, there was a significant difference in tooth color change after 3 weeks(p<0.05). Among them, strawberry and lemon showed higer effects to whitening toothpaste. It is believed that strawberries and lemons have a higher whitening effect than whitening toothpaste. Whitening toothpaste may be replaced with a safe natural whitening effect using strawberries and lemons instead of chemical ingredients that may be harmful to human body.

Study on Skin Whitening and Antioxidant Effect of Anemarrhenae Rhizoma Extract (지모 추출물의 피부 미백 및 항산화 효과 연구)

  • Choi, Chanhun;Jeong, Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.2
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    • pp.67-74
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    • 2020
  • The objective of this study is to investigate the skin whitening and antioxidant effects of the Anemarrhenae Rhizoma extract (ARE). Following the previously studied method, we examined the inhibitory effects of melanin synthesis and tyrosinase activity by using B16F10 cells. First, we measured the Diphenylpicrylhydrazyl (DPPH) assay, nitrite scavenging activity, and superoxide dismutase-like activity to verifying antioxidant efficacy according to skin whitening. In addition, we confirmed the skin whitening efficacy of ARE by measuring gene expression associated with a skin whitening by the Reverse transcription polymerase chain reaction (RT-PCR) method in B16F10 cells. In this study, we confirmed that ARE has skin whitening and antioxidant effects at high concentrations. In particular, ARE at a concentration of 500 ㎍/ml inhibited the expression of Tyrosinase, TRP-2 (tyrosinase-related protein), and MITF (microphthalmia transcription factor) genes better than Arbutin. In conclusion, our results confirmed that ARE has the potential for development as a skin whitening efficacy substance.

A NEW MELANOGENESIS INHIBITOR FROM INGA ALBA (SW.) WILLD.

  • Danoux, L.;Henry, F.;Moser, P.;lGillon, V.;Moretti, C.;Pauly, G.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.520-539
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    • 2003
  • By using sequentially efficacy tests based on tyrosinase, the key enzyme of melanogenesis, then a cell line of melanocytes cultured in vitro, we have been able to detect the whitening potential of a plant extract and then to develop a new whitening Active Ingredient whose the whitening potential was confirmed on cultured melanocytes. Through a phytochemical approach, it seems that the whitening potential could be due to the "tannin" fraction of plant extract. A complementary work is planned to explain more precisely which fractions are responsible for the whitening potential and a clinical test is in progress on 30 Asian skin type volunteers to show the whitening efficacy on human volunteers.

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Layered Receivers for System Combined Layered Space-Time Processing and Space-Time Trellis Codes (계층화 시공간 구조와 시공간 트렐리스 부호를 결합한 시스템에 적합한 계층화 수신기)

  • 임은정;김동구
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.3
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    • pp.167-167
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    • 2004
  • The system combined layered space-time processing and space-time trellis codes (STTC) provide high transmission rate as well as diversity and coding gain without bandwidth expansion. In this paper, two layered receiver structures are proposed. One is the LSTT-MMSE in which received bit streams are decoupled by interference nulling and then decoded by separate STTC decoders. The decoded outputs are cancelled from the received signal before advancing to the next layer detection. The other is LSTT-Whitening employing whitening rather than nulling. The receiver employing whitening process shows several advantages on diversity gain and the required number of receive antennas compare to the convolutional coded space-time processing. The proposed receivers use different decoding order scheme according to each interference suwression. The (4, 3) LSTT-Whitening receiver still achieves 1㏈ gain over the (4, 4) LSTT-MMSE and the (4, 4) coded layered space-time processing.

Layered Receivers for System Combined Layered Space-Time Processing and Space-Time Trellis Codes (계층화 시공간 구조와 시공간 트렐리스 부호를 결합한 시스템에 적합한 계층화 수신기)

  • 임은정;김동구
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.3
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    • pp.9-14
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    • 2004
  • The system combined layered space-time processing and space-time trellis codes (STTC) provide high transmission rate as well as diversity and coding gain without bandwidth expansion. In this paper, two layered receiver structures are proposed. One is the LSTT-MMSE in which received bit streams are decoupled by interference nulling and then decoded by separate STTC decoders. The decoded outputs are cancelled from the received signal before advancing to the next layer detection. The other is LSTT-Whitening employing whitening rather than nulling. The receiver employing whitening process shows several advantages on diversity gain and the required number of receive antennas compare to the convolutional coded space-time processing. The proposed receivers use different decoding order scheme according to each interference suwression. The (4, 3) LSTT-Whitening receiver still achieves 1㏈ gain over the (4, 4) LSTT-MMSE and the (4, 4) coded layered space-time processing.

Characteristics of Bovine Teeth Whitening in Accordance with Gas Environments of Atmospheric Pressure Nonthermal Plasma Jet

  • Sim, Geon Bo;Kim, Yong Hee;Kwon, Jae Sung;Park, Daehoon;Hong, Seok Jun;Kim, Young Seok;Lee, Jae Lyun;Lee, Gwang Jin;Lim, Hwan Uk;Kim, Kyung Nam;Jung, Gye Dong;Choi, Eun Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.250.2-250.2
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    • 2014
  • Currently, teeth whitening method which is applicable to dental surgery is that physician expertises give medical treatment to teeth directly dealed with a high concentration of hydrogen peroxide and carbamide peroxide. If hydrogen peroxide concentration is too high for treatment of maximized teeth whitening effect [1], it is harmful to the human body [2]. To the maximum effective and no harmful teeth whitening effect in a short period of time at home, we have observed the whitening effect using carbamide peroxide (15%) and a low-temperature atmospheric pressure plasma jet which is regulated by the Food and Drug Administration. The gas supplied conditions of the non-thermal atmospheric pressure plasma jet was with the humidified (0.6%) gas in nitrogen or air at gas flow rate of 1000 sccm. Also, the measurement of chemical species from the jet was carried out using the optical emission spectroscopy (OES), the evidence of increased reactive oxygen species compared to non-humidified plasma jet. We have found that the whitening effect of the plasma is very excellent through this experiment, when bovine teeth are treated in carbamide peroxide (15%) and water vapor (0.2 to 1%). The brightness of whitening teeth was increased up to 2 times longer in the CIE chromaticity coordinates. The colorimetric spectrometer (CM-3500d) can measure color degree of whitening effect.

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