• The korean journal of orthodontics
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• v.25 no.2 s.49
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• pp.165-174
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• 1995

The purpose of this study was to evaluated the improve method of demineralization and damage on the enamel stufece related to bonded orthodontic bracket. Enamel surface of the 40 Intact premolars were treated by aicd etching and various fluoride application methods and then maintained in the patient mouth of 3 months. After extraction of all the sampled premolars, enamel surfaces were evaluated by Scanning electron microscope. The obtained results were as follow. 1. Enamel surface relate to bonded orthodontic bracket showed demineralization and damage, slightly. 2. Group 6 treated by $2\%$ NaF iontophoresis presented and almost similarity to nomral enamel surface. 3. Group 2 treated by acid etching had demineralization and damage on the enamel surface much more than other groups treated by various fluoride application methods. 4. Demineralization and damage on the enamel surface caused by bonded orthodontic bracket is improved by various fluoride application methods.

• The korean journal of orthodontics
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• v.3 no.1
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• pp.21-28
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• 1972

저자는 direct bonding system의 pretreatment액 처리후 Epoxy adhesive의 bonding strength의 변화를 측정하기 위해서 발거된 상악 전치 진면 법랑질 표면에 pretreatment액으로서 $65\%$ phosphoric acid를 도포한 실험군과 도포하지 않은 비교군을 비교연구하고 임상에 적용하여 다음과 같은 결과를 얻었다. 1. 법랑질 표면에 pumicing과 $65\%$ phosphoric acid를 도포했을때 joint strength는 현저히 상승했다. 2. Epoxy adhesive의 bonding strength는 plastic attachment를 치아면에 접착유지시키기에 충분하며 임상적으로 이용할 수 있다. 3. Joint area가 클 수록 bonding strength는 증가했다.

• Journal of dental hygiene science
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• v.10 no.2
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• pp.95-100
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• 2010

The purposes of this study were to examine the effect of different fluoridated bleaching solution on the changes in physical and chemical characteristics of tooth. Forty-eight bovine incisors were divided into four groups to receive bleaching treatments, over a 14days period, as follows: no treatment; 10% carbamide peroxide (CP) bleaching; 10% CP containing 0.05% fluoride; and 10% CP containing 0.1% fluoride. All the specimens were highly polished and discolored with commercial COCK.Color and enamel changes were determined with colorimeter, microhardness tester, scanning electron microscope, atomic force microscopy. All the collected data were analyzed with one-way ANOVA. After the bleaching, bleached groups showed the color change(E*). Microhardness of 10% CP group decreased after tooth bleaching. But microhardness of containing fluoride bleached groups increased after tooth bleaching. Enamel surface of 10% CP bleached group showed any apparent morphology and roughness changes compared to the enamel which was stored in distilled water only. These results demonstrated that Fluoridated 10% Carbamide Peroxide have appreciable bleaching effect on bovine teeth and were not adversely affects enamel. Supporting influence of fluoride-containing bleaching solution on remineralization could be observed and further research must be carried out in various active environments to confirm these results clinically.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.4
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• pp.412-418
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• 2017

During orthodontic treatment, formation of white spot lesions (WSLs) around brackets has long been recognized as a potential risk. This study performed to investigate effect of preventing enamel demineralization and remineralization by application of fluoride-containing orthodontic primer. Fifty extracted bovine incisors teeth were randomly allocated to 3 groups: (I) Non-preparation specimens, (II) Application of Light Bond$^{TM}$ as fluoride containing orthodontic primer, (III) Application of Transbond$^{TM}$ XT Primer as traditional orthodontic primer without fluoride. Each group is demineralized under artificial carious solution. The demineralization pattern was evaluated using a Q-ray view, Vickers hardness test and polarized light microscope. The remained primer was calculated as 35 - 50%. The highest surface microhardness was shown on Light Bond$^{TM}$ surface. There were statistically significant differences in Vickers microhardness number between adjacent areas of Light Bond$^{TM}$ and non-prepared area. There was almost no demineralization of the enamel surface under the Light Bond$^{TM}$. At the adjacent site of Light Bond$^{TM}$, the shallow caries pattern and remineralization appearance were also observed. These results suggest that the use of fluoride-containing primers may be useful for bracket attachment to reduce enamel demineralization during orthodontic treatment.

• Journal of dental hygiene science
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• v.8 no.4
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• pp.255-260
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• 2008

The purposes of this study were to examine the effect of 35% hydrogen peroxide (HP) bleaching agent on the changes in physical and chemical characteristics of tooth. The bleached teeth showed an apparent color changes. The whiteness increased linearly within the tested period as the period of bleaching increased. The microhardness between bleached groups after bleaching showed any statistically significant difference according to the paried t-test. The bleached enamel surface showed any apparent morphological changes compared to the enamel which was stored in distilled water only. The difference of the total mineral contents for the distilled water and hydrogen peroxide did not show statistical significance. These results demonstrated that bleaching using 35% hydrogen peroxide were adversely affects application time of experimental group and may confirm the safety of using these agents for a short time in dentist-monitored bleaching.

• The korean journal of orthodontics
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• v.29 no.4 s.75
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• pp.483-490
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• 1999

Interdental enamel stripping is an usual method for correction of abnormal tooth shape and tooth size discrepancy which is one of the etiologic factors of malocclusion. Clinically it Is useful to correct the minor crowding in anterior teeth and posterior occlusion during finishing stage of orthodontic treatment. But this procedure has risks such as irreversible tooth reduction and remaining roughness of enamel surface can accumulate plaque which can evoke periodontal problem. Even if various methods were introduced to minimize the enamel surface roughness, their evaluation was limited in morphologic differences by scanning electronic microscope(SEM). The purpose of this study was to compare the various interdental enamel stripping method by SEM and to quantify the difference of surface roughness by use of Surfcorder SEF-30D(Kosaka Lab. Ltd.) which can measure the roughness of surface. The stripping methods were divided into mechanical and mechanical-chemical method. Air-rotor stripping and separating strip were used for mechanical stripping and $37\%$ phosphoric acid was used for chemical stripping. The enamel surface roughness after mechanical or mechanical-chemical stripping of interproximal surfaces of premolars which were extracted for orthodontic purpose were measured and compared by means of SEM and $Surfcorder^{\circledR}$, the results were as follows. 1. Enamel surface of primary treated by coarse diamond bur and separating strip groups showed highest value of roughness. 2. To compare the primary treated groups between mechanical and mechanical-chemical method, the latter group showed lower value of roughness remarkably. 3. Mechanical stripping groups which were treated both coarse and fine instrument showed lower value of roughness as much as non treated group. 4. The use of Pumice for final polishing did not show significantly smoothening the stripped enamel surface any more.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.266-276
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• 2020

The purpose of this study was to compare the remineralization effect of 38% silver diamine fluoride (SDF) and 5% sodium fluoride (NaF) varnish on artificially induced enamel caries. The present study standardized the physiochemical characteristics of the tooth structure using bovine teeth, realized the wash-off action of agents using a saliva, reproduced an environment similar to mouth through pH-cycling, and comparatively assessed the remineralization effect of 38% SDF and 5% NaF varnish in a non-destructive method using micro-CT. And the remineralized enamel surface structure was analyzed by scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). In both SDF and NaF varnish, mineral density (△Hounsfield unit value) and the volume of enamel restored to normal mineral density through remineralization gradually increased with time. And the SDF showed a much higher level of increase in mineral density at all depths and remineralized volume than NaF varnish. According to SEM analysis, the surface roughness decreased in the order of artificial saliva, NaF varnish and SDF. In addition, EDS analysis showed that silver ion was precipitated on the enamel surface in SDF group. In conclusion, SDF had a greater remineralization effect than NaF varnish on demineralized enamel.

• Journal of Periodontal and Implant Science
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• v.33 no.2
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• pp.127-137
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• 2003

치과용 임플란트 실패의 주요 원인은 임플란트 표면에 부착되는 세균의 침착의 결과로 생기는 임플란트 주위염이다. 구강 내에서 세균성 치태의 침착은 치태가 부착하는 기질 표면의 물리적 성상과 타액성 피막의 성분에 영향을 받으며 형성된 피막의 유기질 성분의 차이가 치태의 성분과 병원성에 영향을 미친다. 최근 연구에 의하면 생체재료의 표면에 침착되는 치태세균은 사용되는 재료에 따라 특이한 세균 침착을 보이며 이는 초기 타액성 피막의 차이에 의한 것으로 알려져 있다. 이 연구의 목적은 플라즈마분사법으로 표면 처리된 타이태늄 임플란트에 흡착되는 타액성 단백질 피막의 특성을 정성적인 방법으로 분석하는 데 있었다. 법랑질 조각과 플라즈마분사법으로 표면 처리된 타이태늄 임플란트를 스프린트에 치실을 이용하여 연결한 장치를 구강 내 장착하여 2시간 동안 피막이 침착되게 한 후 피막을 분리 추출하여 냉동 건조시켰다. 재수화 과정을 거치고 나서 전기 영동법과 Western transfer 분석을 통해 단백질 성분에 관한 분석을 시행하였다. 사람의 총 타액과 이하선 타액 및 악하선-설하선 타액을 수집기를 이용하여 채취하고 같은 방법으로 처리한 후 성분분석을 실시하였다. 피막 흡착 전후의 표면변화를 주사전자현미경을 이용하여 관찰하였다. 실험결과 타이태늄 임플란트에 흡착된 피막은 법랑질 표면의 피막과는 다른 단백질 성분을 가지고 있었으며, 주로 악하선-설하선 타액에서 유래하였다. 임플란트와 법랑질 표면 모두에서 흡착된 피막에는 아밀라제, 분비성 면역 글로불린A 및 락토페린이 존재함을 알 수 있었으나 법랑질의 경우는 blotting이 약하게 나타났다. 주사전자현미경 관찰결과 시편의 표면에 균질한 피막이 덮고 있었으며 세균의 부착은 거의 관찰되지 않았다. 이상의 실험 결과들을 통하여 플라즈마분사법으로 표면 처리된 타이태늄 임플란트 표면에 부착된 타액성 단백질 성분은 법랑질과는 차이가 있음을 알 수 있었으며, 이러한 차이는 치태세균의 종류 및 병원성에 영향을 미칠 것으로 생각된다. 법랑질과 타이태늄 임플란트는 기질과 표면구조가 다르므로 표면에 형성 되는 치태성분도 다르다는 사실과 본 연구 결과를 종합하여 볼 때, 타이태늄 임플란트 표면에 흡착되는 초기 타액성 단백질의 성불이 타이태늄 표면에 침착되는 미생물 군의 조절에 중요한 역할을 가지고 있으며, 임플란트 치료 시에 올바른 치태 관리법의 교육을 통하여 환자 스스로 적절한 관리를 하도록 함으로써 임플란트 치료의 성공률을 높일 수 있을 것으로 생각된다.

• The korean journal of orthodontics
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• v.38 no.6
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• pp.407-415
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• 2008

Objective: The aim of this study was to evaluate the remineralization of interdentally stripped teeth after fluoride gel or hydroxyapatite paste application. Methods: After interdental stripping, 1.23% fluoride gel or 10% hydroxyapatite paste was applied three times a day, with a duration of four minutes, for a week. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to compare the change of surface contents and crystal structures before and after the application of fluoride gel or hydroxyapatite paste. Results: EDS analysis indicated that calcium contents were increased after 10% HAp paste application on stripped enamel (p < 0.01). SEM view showed that enamel surfaces in groups of 1.23% APF gel or 10% HAp paste application were smoother than those of control group, which was regarded as filling of the pore structure. And pores between crystal structures in groups treated with 1.23%, APF gel or 10% HAp paste were smaller than those of control group. Conclusions: Application of APF or HAp on stripped enamel could positively influence on the surface contents or crystal structure.

• Journal of Oral Medicine and Pain
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• v.24 no.4
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• pp.411-420
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• 1999

과거 수십년간 여러 가지 다른 레이저를 이용한 치아경조직에 대한 몇 가지의 생체외적 실험이 이루어졌다. 그러나 그 결과는 좋지 못하였다. 그러한 주 문제는 열작용이었다. 미국 식품의약국(FDA)에서 사용하도록 허가된 Er:YAG 레이저는 인간의 생체 치아를 삭제할 수 있는 최초의 레이저이다. 치아 삭제가 열작용의 원리에 의해 이루어지기는 하지만, 경조직의 미세폭발에 의하기 때문에 주변의 경조직과 연조직에 미치는 열작용은 거의 없다. 본 연구에서는 최근 국내에서 최초로 개발된 Er:YAG 레이저를 사용하여, 상아질과 법랑질에 일회 조사시 다양한 에너지 수준에 따른 삭제율을 연구하였다. 건조된 10개의 치아가 선택되었으며, 각각은 에폭시 레진에 포매되어 경화되었다. 그 후 다섯 개의 치아는 저속회전 다이아몬드 휠로써 교합면 삭제를 통해 상아질이 노출되었으며, 나머지 다섯 개의 치아는 협측 혹은 설측을 삭제하여 평평한 표면의 법랑질을 만들도록 하였다. 준비된 상아질과 법랑질 치아의 표면은 각각의 에너지 수준의 레이저를 조사할 6개의 구획으로 나누어 표본으로 삼았다. 상아질과 법랑질 표본은 에너지 수준에 따른 5개의 실험군(40 mJ, 80 mJ, 120 mJ, 160 mJ, 200 mJ)으로 나누어 그 삭제율을 분석하였다. 삭제된 부피는 삼차원 영상 표면분석기로 측정하였으며, 통계적으로 분석하였으며, 그 결과는 다음과 같다. 1. 상아질과 법랑질간의 삭제율의 차이는 통계적으로 유의한 차이가 있었다(p<0.0001). 2. 에너지 수준에 따른 삭제율의 차이는 통계적으로 유의한 차이가 있었다(p<0.0001). 3. 각각의 에너지 수준에서 상아질과 법랑질간의 삭제율의 차이는 통계적으로 유의한 차이가 있었으나(p<0.05), 40 mJ과 80 mJ에서는 유의한 차이를 보이지 않았다. 4. 상아질에서 각각의 에너지 수준 간의 삭제율이 유의한 차이를 보였으나(p<0.01), 160 mJ과 200 mJ간에는 삭제율의 유의한 차이가 없었으며, 법랑질에서도 각각의 에너지 수준 간의 삭제율이 유의한 차이를 보였으나(p<0.01), 120 mJ, 160 mJ, 200 mJ 간에 유의한 차이를 보이지 않았다. 본 연구에서는 건조된 치아에 다양한 에너지 수준의 Er:YAG 레이저를 적용했을 경우 상아질과 법랑질의 삭제 부피를 연구하여 정량화 및 통계적 분석을 하였다. 그 결과, Er:YAG 레이저는 치아경조직의 삭제에 매우 유용하였으며, 앞으로도 이를 임상적으로 널리 이용하기까지 좀더 다양하고 심화된 연구가 필요할 것으로 사료된다.