• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.4
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• pp.393-403
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• 2011

The purpose of this study was to analyze and compare survival rates of resorbable blast media(RBM) surface and acid-etched surface implants being usually used in clinics. RBM surface implants (USII, Osstem, Busan, Korea) or acid-etched surface implants ($Osseotite^{(R)}$, Biomet $3i^{[TM]}$, FL, USA) were placed in edentulous area of 140 patients between January of 2005 and March of 2007. The number of implants was 304, and 152 out of them were RBM surface implants while another 152 were acid-etched surface implants. According to the evaluation items, the survey was performed before and after the implants installations. The 3-year survival rates of both kind of implants were calculated. 1. Total of 152 RBM surface implants were placed. Among them, one implant was failed, which was implanted in the posterior mandible with D2 bone quality. The failure was resulted from fracture of the fixture. Others showed good results and survival rate of RBM surface implant was 99.34%. 2. Total of 152 acid-etched surface implants were placed. Seven implants of them were failed, thus, survival rate was 95.39%. The causes of the failures were considered as infection, overheat and the lack of initial stability. In this research, both implants showed good 3-year survival rate, although RMB surface implant represented a better result.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.242-253
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• 1996

Penetration degree of several dyes into dentinal tubules in vivo was compared with in vitro, and experimental sensitivity of those dyes was investigated in 64 canines of 16 cats. Dentin 1mm below cusp tip was exposed by cross-sectioning with diamond disc. Pulp of 32 canines were extirpated through cervical cavities. In the presence of smear layer or after add-etching with 37% phosphoric acid to the exposed dentin surface, acrylic collar and resin cap was attached to keep dyes. 52 mmol/$\ell$ Evans' blue, 2% Methylene blue, 10 % Silver nitrate and 5% Fluorescene were then applicated on each 4 canines respectively for 30 minutes. After rinsing, the canines were ground-sectioned longitudinally and linear dye penetration was measured under microscope. The results obtained were as follows ; 1. Evans' blue and Methylene blue penetrated significantly(P<0.05) more in vitro than in vivo only in the cases that exposed dentin surfaces were not etched with acid. 2. Silver nitrate penetrated significantly(P<0.05) more in vitro than in vivo in both cases that exposed dentin surfaces remained intact and were etched with acid. 3. The penetration degree of Fluorescene did not show statistical significance between in vivo and in vitro or in acid-etched and in not acid-etched cases.

• Korean Journal of Materials Research
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• v.16 no.1
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• pp.63-67
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• 2006

The characteristics of the wet-etching of ZnO thin films were investigated using hydrochloric and phosphoric acid solutions as etchants. The etch rate of ZnO films, using highly diluted hydrochloric acid solutions at a concentration of 0.25% in deionized water, was determined to be about 120 nm/min, and linearly increased with increasing the acid concentration, resulting in $1.17{\mu}m/min$ when a 2% HCl solution was used. The surface of ZnO etched by an HCl solution, observed by scanning electron microscopy, showed a rough morphology with a high density of hexagonal pyramids or cones with sidewall angles of about ${\sim}45^{\circ}C$. Moreover, the sidewall angles of the masked area were similar to those of the pyramids on the surface. In comparison, the surface of ZnO etched by a phosphoric acid had a smooth surface morphology. The origin of this difference is from the very initial stage of etching, indicating that the etch-mechanism is different for each solution. Furthermore, when $H_3PO_4$ was added to the HCl aqueous solution, the morphology of the etched surface was greatly enhanced and the sidewall angle was also increased to about $65^{\circ}C$.

• The Journal of Advanced Prosthodontics
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• v.10 no.1
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• pp.73-78
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• 2018

PURPOSE. The purpose of this study was to analyze the effects of two different implant surface treatments on initial bone connection by comparing the Removal Torque Values (RTQs) at 7 and 10 days after chemically modified, sandblasted, large-grit and acid-etched (modSLA), and Laser-etched (LE) Ti implant placements. MATERIALS AND METHODS. Twenty modSLA and 20 LE implants were installed on the left and right tibias of 20 adult rabbits. RTQs were measured after 7 and 10 days in 10 rabbits each. Scanning electron microscope (SEM) photographs of the two implants were observed by using Quanta FEG 650 from the FEI company (Hillsboro, OR, USA). Analyses of surface elements and components were conducted using energy dispersive spectroscopy (EDS, Horiba, Kyoto, Japan). RESULTS. The mean RTQs were $12.29{\pm}0.830$ and $12.19{\pm}0.713$ Ncm after 7 days (P=.928) and $16.47{\pm}1.324$ and $16.17{\pm}1.165$ Ncm after 10 days (P=.867) for LE and modSLA, respectively, indicating no significant inter-group differences. Pore sizes in the LE were $40{\mu}m$ and consisted of numerous small pores, whereas pore sizes in the modSLA were $5{\mu}m$. In the EDS analysis, Ti, O, and C were the only three elements found in the LE surfaces. Na, Ca, Cl, and K were also observed in modSLA, in addition to Ti, O, and C. CONCLUSION. The implants showed no significant difference in biomechanical bond strength to bone in early-stage osseointegration. LE implant can be considered an excellent surface treatment method in addition to the modSLA implant and can be applied to the early loading of the prosthesis clinically.

• The Journal of the Korean dental association
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• v.21 no.5 s.168
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• pp.395-402
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• 1983

The purpose of this study was to apply the etched metal ceramometal retainer using a composite resin and acid-etch procedure with minimal tooth reduction of abutments for the replacement of one missing anterior or posterior tooth. Author obtained the following conclusions. 1. conservation of tooth structure and minimal chair time and patient expense were the primary advantages of etched metal retainer. 2. This fixed partial denture permitted good esthetic results. 3. This retainer was successfully applied for the replacement of one missing anterior or posterior tooth. 4. Proper retainer etching ws an important procedure. 5. Etched castings could be applied to periodontal splinting and post orthodontic fixation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.5
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• pp.396-405
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• 2001

Osseointegrated implants are used for the fixation of dental prosthesis with good long-term clinical results. In an attempt to improve the quantity and quality of the bone-implant interface, numerous implant modification have been used. Implants surface modifications have been used such as titanium-plasma sprayed, hydroxyapatite-coating, sandblasted, sandblasted and acid-etched, acid-etched. Rough surface implants have greater implant surface area and enhance the bone-implant interface and improve stabilization. The purpose of present study was to evaluate light microscopic and scanning microscopic examinations and removal torque value of newly developed calcium phosphate blast and acid-etched implant in the femur of rabbits. Titanium plasma sprayed(TPS) implant served as controls. After 12 weeks of healing of the femurs of 12 rabitts, the implant-containing segments of femur were removed on bloc and bone block including sections. Histologic examination and histomorphometric and removal torque values comparision were made for two implants. Obtained results are follows: 1. Newly developed calcium phosphate blasted and acid-etched implants were in close contact with bone under light microscopic examinations. 2. New implants showed mean bone-to implant contact 59.8%, whereas TPS implants showed mean bone-to implant contact 54.5% (statistically no difference p<0.05). 3. New implants showed mean bone density 56.7%, whereas TPS implants showed mean bone density 49.2% (statistically difference p<0.05). 4. New implants demonstrated mean removal torque values 40.5Ncm, whereas the mean removal torque values of TPS implants ranged 39.3Ncm. No statistical differences(p<0.05) were observed between two groups of implants nor was there any difference between the two implants at the clinical level.

• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.497-507
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• 1996

The aim of present study in vitro was to evaluate and compare the effects of different washing times of enamels etched with low phosphoric acid solution which makes unsoluble salts and etched but contaminated with saliva on shear bond strength of an orthodontic adhesive to enamel, and to observe the washing effect on the etched enamel surface by scanning electron microscope. All brackets were bonded with Mono-$Lok2^{TM)}$) on the labial surface of extracted human bicuspids after etching with $20w/w\%\;and\;37w/w$ and phosphoric acid solution for 60seconds and then washing for 0,5,10 and 20seconds respectedly. After etching with $37w/w\%$ phosphoric acid solution and contaminating with saliva for 30seconds and then washing for 0,5,20 and 30seconds and re-etching for 10seconds. After 24hours passed in the $37^{\circ}C$ water bath, the shear bond strengths were measured on Universal Test Machine. The data were evaluated and tested by ANOVA and Duncan's multiple range test, and those results were as follows. 1. There was no significant differences between (p>0.05) shear bond strength of bonded brackets with 5, 10, 20seconds washing etched enamel using $37{\%}w/w{\%}$ phosphoric acid solution. 2. The shear bond strength of bonded brackets with $20w/w\%$ phosphoric acid and then washing for 5seconds showed bonded strength durable to occlusal force but its coefficiency score was high and etched surface was not cleaned completely and therefore it was assumed that its clinical application is not applicable. 3. There was no significant differences between (p>0.05) shear bond strengths of bonded brckets with washing for 5seconds etched enamel using $37w/w\%$ phosphoric acid solution and 10,20 seconds washing etched enamel using $20w/w\%$ phosphoric acid solution. 4. The shear bond strength of washing for 5seconds etched enamel which was contaminated with saliva showed sufficient bonded strength durable to occlusal force but its coefficiency score was high and therefore its clinical application was not applicable. 5. After etching, the sample contaminated with saliva showed the sufficient shear bond strength even washing 20seconds without re-etching.

• Restorative Dentistry and Endodontics
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• v.5 no.1
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• pp.13-18
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• 1979

The purpose of this study was to measure the roughness on the acid -etching surface. The etching agents of three-kinds composite resins were used to etch the tooth surface. Newly extracted I5-anterior teeth were invested with self-curing acrylic resin, and the labial surface was exposed. The exposed labial side was polished with abrasive papers and finally polished on polishing machine with zinc oxide powder. After the teeth were polished, the specimens were washed by water and dried by air. Surface roughness tester, Taylor-Habson's Taly Surf-10, (Fig-1) was used to measure roughness of this unetched tooth surface. And that, the specimens were divided into three groups. The first group was etched with Restodent etchant, the second group was etched with Nuva-system etchant, and Hi-pol etching agent was used in the third group. And the surface roughness tester was used to measure roughness of the etching teeth surface. The results obtained were as follows. 1. The roughness of acid-etched enamel were increased $2{\mu}m$ to $6{\mu}m$. 2. Hi-pol etchant produced the smoothest surface($2.3{\mu}m$). 3. Restodent etchant($3.8{\mu}m$) and Nuva-system etchant($3.7{\mu}m$) produced rougher surface than Hi-pol.

• The korean journal of orthodontics
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• v.26 no.3
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• pp.309-316
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• 1996

The purpose of this study was to determine the effect of salivary contamination of etched enamel on shear bond strength of a bracket adhered to etched enamel. Eighty extracted human permanent premolars were used in this study. These samples were divided into two groups. Buccal surface of samples were etched in vitro with 38% phosphoric acid for 15 seconds and 60 seconds. Each group was divided into four subgroups. Etched enamel surfaces were contaminated with saliva for 0, 1, 20, 60 seconds, washed and dried. Test surfaces were examined using scanning electron microscope(SEM). The shear bond strength of each sample was determined with a universal testing instrument(Instron Co. Model 4201). Results were as follows; 1. Salivary contamination for 1, 20, 60 seconds did not affect shear bond strength when compared with the uncontaminated enamel group. 2 There was no significant difference(P>.05) in shear bond strength between 15 sec. and 60 sec. etching in uncontaminated enamel groups. 3. When samples were examined using SEM, organic materials coated enamel surface masked the etched pattern partially.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.70-71
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• 2007

Multicrystalline silicon(mc-Si) solar cells are steadily increasing their share of the PV market due to the lower material costs. However, commercial mc-Si solar cells have lower efficiency than singlecrystalline silicon solar cells. To improve efficiency of mc-Si solar cells, it is important to reduce optical losses from front surface reflection. Isotropic etching with acid solution based on hydrofluoric acid(HF) and nitric acid$(HNO_3)$ is one of the promising methods that can reduce surface reflectance for mc-Si solar cells. Anisotropic etching is not suitable for mc-Si because of its various grain orientations. In this paper, we isotropically etched mc-Si using acid solution. After that, etched surface was observed by Scanning Electron Microscope(SEM) and surface reflectance was measured. We obtained 29.29% surface reflectance by isotropic etching with acid solution in wavelength from 400nm to 1000nm for fabrication of mc-Si solar cells.