• Restorative Dentistry and Endodontics
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• 제35권2호
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• pp.134-142
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• 2010

이 연구의 목적은 상아질 지각과민증 모드의 Er,Cr:YSGG 조사가 복합레진 수복물의 미세인장 결합강도에 미치는 영향을 평가하는 것이다. 20개의 발거된 대구치를 사용하여 Er,Cr:YSGG 레이저 적용 유무와 사용된 접착제 시스템(Optibond FL과 Clearfil SE bond), 산의 적용 시간(15초와 20초)에 따라 여섯 그룹으로 나누었다. 노출된 교합면 상아질에 레이저 조사 후 접착제를 도포하고 복합레진으로 수복하였다. 24시간 동안 실온의 증류수에 보관 후 각 그룹 당 12개의 시편을 준비하였다. 모든 시편의 미세인장 결합강도를 측정하고 파절 양상을 관찰하였다. 더불어 레이저를 조사한 시편과 조사하지 않은 시편을 주사현미경을 이용하여 관찰하여 다음과 같은 결과를 얻었다. 1. 레이저를 조사한 그룹은 레이저를 조사하지 않은 그룹보다 낮은 미세인장 결합강도를 나타내었다. 2. 레이저 조사 유무와 관계없이, Optibond FL이 Clearfil SE bond보다 높은 미세인장 결합강도를 나타냈으며, Optibond FL을 사용했을 때 산부식 시간이 20초인 경우가 15초인 경우보다 더 높은 값을 나타내었다. 3. 레이저를 조사한 상아질의 SEM 사진은 관간상아질보다 관주상아질이 더 두드러져 보이며, 상아세관이 열려있으며 도말층은 관찰되지 않았다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권3호
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• pp.222-228
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• 2009

Objectives: This study is aimed to compare the wound healing processes between conventional scapel wound and Er,Cr:YSGG (Erbium,Chromium, Yttrium, Scandium, Gallium, Garnet) laser wound using experimental animals. Experimental Design: Two types of wounds were made by linear and round incisions using scalpel and Er,Cr:YSGG laser, respectively, on the thigh of Sprague-Dawley rats. Sprague-Dawley rats were serially sacrified as follows: post operative 12, 24, 48 hours, and 3, 7, 14 days. The skin wounds were grossly and microscopically analyzed during the healing period. Result: The Er,Cr:YSGG laser incision showed better wound healing for the linear incision experiment than the scapel incision. Whereas the scapel incision showed better wound healing for the round incision experiment than the Er,Cr:YSGG linear incision. As the Er,Cr:YSGG laser damage in the round incision experiment could be much increased compared with the round incision by scapel. So, the round incisions by the Er,Cr:YSGG laser were resulted in the poor wound healing compared with those by the scapel. Conclusion: The Er,Cr:YSGG laser is more favorable for the fast linear incision, while the scapel is more favorable for the modified round incision.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권5호
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• pp.454-469
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• 2006

Today, there is considerable evidence to support a cause-effect relationship between microbial colonization and the pathogenesis of implant failures. The presence of bacteria on implant surfaces may result in an inflammation of the peri-implant mucosa, and, if left untreated, it may lead to a progressive destruction of alveolar bone supporting the implant, which has been named as peri-impantitis. Several maintenance regimens and treatment strategies for failing implants have been suggested. Recently, in addition to these conventional tools, the use of different laser systems has also been proposed for treatment of peri-implant infections. As lasers can perform excellent tissue ablation with high bactericidal and detoxification effects, they are expected to be one of the most promising new technical modalities for treatment of failing implants. It is introduced that Er,Cr:YSGG laser, operating at 2780nm, ablates tissue by a hydrokinetic process that prevents temperature rise. We studied the change of the titanium implant surface under scanning electron microscopy after using Er,Cr:YSGG laser at various energies, irradiation time. In this study, Er,Cr:YSGG laser irradiation of implant fixture showed different effects according to implant surface. Er,Cr:YSGG laser in TPS surface with RBM not alter the implant surface under power setting of 4 Watt(W) and irradiation time of 30sec. But in TPS surface with $Ca_3P$ coating alter above power setting of 2W and irradiation time of 10sec. TPS surface with RBM showed microfracture in 4W, 30sec and TPS surface with $Ca_3P$ coating showed destruction of fine crystalline structure, melting in excess of 2W, 10sec. We concluded that proper power setting, air, water of each implant surface must be investigated and implant surface must be irradiated under the damaged extent.

• 대한치과의사협회지
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• 제53권12호
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• pp.917-925
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• 2015

LASER application has many advantages in the field of dentistry, however, it is not easy to apply dental LASER in general practice. Various LASER systems are in the market and it is little bit confused which LASER systems are useful. Most of all, it is important to select the appropriate LASER system to their own usage. In the present article, I introduce several LASER system such as $CO_2$, Diode, Nd:YAG, Er:YG, Er,Cr:YSGG, and its application according to specific disease criteria.

• 대한치과의사협회지
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• 제48권6호
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• pp.469-477
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• 2010

The purpose of this study was to evaluate the effect of two dentin desensitizers and Er,Cr:YSGG laser for dentinal tubule occlusion. Twenty recently extracted single-rooted human teeth were used to obtain root dentinal fragments. The crowns were cut approximately 1mm below the cementum enamel junction(CEJ). A second cut was used to remove the apex of the root. Subsequently, a longitudinal cut was made in order to obtain 2 fragments from each root sample. The cementum from the cervical portion was removed using a high-speed diamond-coated bur in order to expose the dentin. To open dentinal tubules, forty samples were treated with 50% citric acid for 2 min and then rinsed under distilled water for 1 min. These were divided into four groups of ten samples each. The first group served as a control group. In group 2, the samples were irradiated with the Er,Cr:YSGG laser(Waterlase MD, Biolase, USA). In group 3, the samples were treated with Bisblock and ONE-STEP PLUS(Bisco, USA). In group 4, the samples were treated with Gluma comfort bond & Desensitizer(Heraeus Kulzer, Germany). All the samples were examined using Scanning electron microscopy(Hitachi, S-4700, Japan) with two different magnifications(X2000, X5000). These images were assessed by one examiner who was blind to the experimental procedure, using the index of smear layer removal. The distribution of smear layer removal grades was tested using Fisher's exact test. On the order hand, in order to evaluate the occluding effect of two dentin desensitizers and Er,Cr:YSGG laser, the number of exposed dentinal tubules was counted in each group. These were evaluated using the Kruskal-Wallis test with significance predetermined $\alpha$=0.05. There were statistically significant differences between the three groups(Er,Cr:YSGG laser, Bisblock+ONE-STEP PLUS, Gluma comfort bond & Desensitizer) and control group.

• 대한치과교정학회지
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• 제40권2호
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• pp.87-94
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• 2010

전단결합강도를 강화하기 위해 레이저를 이용한 부식과 산을 이용한 부식의 비교 연구가 많이 진행되어왔다. 본 연구에서는 Er,Cr:YSGG laser와 전통적인 산부식법을 혼합한 방법의 전단결합강도의 변화에 대한 평가를 하고자 한다. 교정적인 목적으로 발치된 64개의 건전한 소구치를 이용하여 16개씩 4개의 군으로 나누었다. 첫 번째 군은 37% 인산을 15초 적용시키는 전통적인 부식 방법을 택하였고, 두 번째 군은 물방울레이저로 1.5 W로 10초간 부식시킨 후 전통적인 산부식 방법을 시행하였다. 세 번째 군은 두 번째 군과 같지만 산부식을 먼저 시행한 후 물방울레이저로 부식시켰다. 네 번째 군은 물방울레이저를 이용하여 1.5 W로 15초간 부식시켰다. 이후 전단결합강도의 측정 및 치아 표면의 특징 관찰, 그리고 접착제잔류지수를 평가하였다. 두 번째, 세 번째 군은 첫 번째, 네 번째 군에 대하여 전단결합강도가 높게 측정되었다. 하지만 두 가지 기법의 복합사용 순서를 달리한 두 번째, 세 번째 군 사이에는 통계적으로 유의한 차이가 나지 않았다. 기존 산부식을 이용한 브라켓 접착법보다 산부식과 Er,Cr:YSGG laser를 복합적으로 사용 시, 향상된 전단결합강도를 얻을 수 있다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권5호
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• pp.428-436
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• 2008

For Longevity of implant, considerations of biomechanical and microbiological aspects must be done. Recently, due to the remarkable development of bone grafting procedure. Implant has been implanted into the more favorable sites but peri-implantitis resulted from periodontal bacteria may obscure the long-term prognosis. Although many different modalities have been introduced to treat the failed implant. Implant's surface and irreversible bony destruction around the implant prevents good result. After Er,Cr:YSGG (waterlase) laser using the wave-length of 2780nm has been introduced to dental field, good results have been reported. Because waterlase uses the hydrokinetic force of water. It is excellent device to detoxify the implant surface mechanically without the heat generation and damage to the implant surface. We designed to evaluate waterlase effect on the peri-implantitis has been occurred after implantation. Four beagle dogs were involved. We have made four premolar extraction in each right and left side of the lower jaw and placed two implants in the anterior of the jaw as a control and six implant were placed posterior in each socket after extraction immediately as an experimental group. We tied floss-silk in each implant to make peri-implantitis intentionally. After three months, we explored peri-implant sites on each experimental fixtures. Using waterlase laser irradiation was performed on that implantitis sites under 3W, air 30% and water 20% intensity for 2 minutes. In control group, we repositioned the flap to cover the exposed fixture without any supportive care. Three months later, we sacrificed experimental animals and extracted and preparated bone blocks with Donath and Breuner (982), Donath (988)'s methods and examined under microscope. We have obtained good re-osseointegration around fixtures after treating with waterlaser irradiation. But it was shown fibroosseointegration in the control group.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권5호
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• pp.396-405
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• 2010

Purpose: This study was performed to find out the effects of the Er:YAG laser (Key Laser) & Er,Cr:YSGG laser (Water Laser) on inflammatory tissues. Materials and Methods: It was performed on about 20 g, 6 weeks male ICR mouses. They were grouped into the control (negative), the inflammation induced 'control'(positive), Er,Cr:YSGG laser exposured group after inducing inflammation, Er:YAG lasere exposured group after inducing inflammation each 15 mouses. The mouses were applicated 0.5% DNFB 1 cc on ear skin twice a day for 4 days until symptom expression. After laser exposure, ear tissues were extracted and defined gene expression by RT-PCR. Then, tissue staining, lymphocytes observation, electromicroscophic laboratory were carried out. Results: Interleukin-$1{\beta}$ was expressed much less in the A-laser exposed group. Interleukin-$1{\beta}$ & Tumor Necrosis Factor-${\alpha}$ were expressed 7 times lesser in the A-laser exposed group. The number of Lymphocytes related to inflammation was decreased rapidly in the A-laser exposed group in vivo. he number of cavity recovered normal was a little bigger in the A-laser exposed group after 5 days Conclusion: The expression of IL-$1{\beta}$ & TNF-${\alpha}$, hitologic change, observation with electron microscope shows that Erbium laser exposure causes lesser inflammation with A-laser rather than B-laser.

• 대한치과보철학회지
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• 제46권5호
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• pp.520-527
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• 2008

목적: 이 연구는 산부식 대신 레이저로 표면처리를 하였을 때 복합레진과의 전단결합강도에 어떤 영향을 주는지 알아보기 위해 시행되었다. 재료 및 방법: 치아 우식증이 전혀 없는 건전한 최근에 발치된 대구치를 레진으로 매몰하고 상아질을 노출시킨 뒤 표면연마를 시행하 였다. 치아는 10개씩 4그룹으로 나누었다. 1) 아무 처리도 하지 않은 군, 2) 35% 인산으로 산부식한 군, 3) Er:YAG laser 레이저 처리된 군, 4) Er,Cr:YSGG laser로 처리된 군. 시편에 상아질 접착제 Single Bond2 (3M/ESPE)를 도포하고, 직경 3 mm, 높이 3 mm의 투명한 플라스틱관을 치아면 위에 두고 복합레진을 축성하였다. 모든 시편은 24시간동안 $37^{\circ}C$증류수에 보관 후 만능시험기를 이용하여 전단결합강도를 측정하였다. 결과: 레이저 처리시 각각 Er:YAG 레이저 처리는 $3.98{\pm}0.88$ MPa, Er,Cr:YSGG 레이저 처리는 $3.70{\pm}1.55$ MPa의 결합강도를 보였고, 통계적으로 유의한 차이를 나타내지 않았다. 아무 처리도 하지 않은 군의 결합강도는 $1.52{\pm}0.42$ MPa로 가장 낮은 결합강도를 나타내었고, 산처리를 한 군이 $7.10{\pm}1.86$ MPa로 가장 높은 전단결합강도를 보였으며, 이들은 레이저 처리한 군과 비교시 통계적으로 P < .001 유의수준에서 유의한 차이가 있는 것으로 나타났다. 결론: 치아와 레진의 전단결합강도 비교시 레이저 처리는 아무 처리도 않은 군에 비해서는 높지만 인산 etching보다 그 결합력이 떨어진다.

• 대한치과의사협회지
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• 제56권7호
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• pp.385-390
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• 2018

Laser means "Light amplification by stimulated emission of radiation". Laser have unique characteristics according to wavelength. Wavelenth of Waterlase is 2780nm and it can be absorbed to water and hydroxyapatite. When laser is applied to some material, its temperature goes up due to laser's energy. But in dental treatment high temperature is not good for teeth. High temperature can make dental pulp and bone necrosis. Waterlase can be absorbed to water droplet, so when it burst, it can cut soft and hard tissue without raising temperature. so it is so proper to dental treatment.