• Journal of Periodontal and Implant Science
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• v.48 no.3
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• pp.164-173
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• 2018

Purpose: The aim of this study was to evaluate the antimicrobial effect of a newly devised toothbrush with light-emitting diodes (LEDs) on Porphyromonas gingivalis attached to sandblasted and acid-etched titanium surfaces. Methods: The study included a control group, a commercial photodynamic therapy (PDT) group, and 3 test groups (B, BL, and BLE). The disks in the PDT group were placed in methylene blue and then irradiated with a diode laser. The B disks were only brushed, the BL disks were brushed with an LED toothbrush, and the BLE disks were placed into erythrosine and then brushed with an LED toothbrush. After the different treatments, bacteria were detached from the disks and spread on selective agar. The number of viable bacteria and percentage of bacterial reduction were determined from colony counts. Scanning electron microscopy was performed to visualize bacterial alterations. Results: The number of viable bacteria in the BLE group was significantly lower than that in the other groups (P<0.05). Scanning electron microscopy showed that bacterial cell walls were intact in the control and B groups, but changed after commercial PDT and LED exposure. Conclusions: The findings suggest that an LED toothbrush with erythrosine treatment was more effective than a commercial PDT kit in reducing the number of P. gingivalis cells attached to surface-modified titanium in vitro.

• Journal of Korean Dental Science
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• v.9 no.1
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• pp.19-27
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• 2016

Purpose: Laser treatment has become a popular method in implant dentistry, and lasers have been used for the decontamination of implant surfaces when treating peri-implantitis. This study was performed to evaluate the effects of an Erbium-doped:Yttrium-Aluminum-Garnet (Er:YAG) laser with different settings on machined (MA), sand-blasted and acid-etched (SA), and resorbable blast media (RBM) titanium surfaces using scanning electron microscopy and confocal microscopy. Materials and Methods: Four MA, four SA, and four RBM discs were either irradiated at 40 mJ/20 Hz, 90 mJ/20 Hz, or 40 mJ/25 Hz for 2 minutes. The specimens were evaluated with scanning electron microscopy and confocal microscopy. Result: The untreated MA surface demonstrated uniform roughness with circumferential machining marks, and depressions were observed after laser treatment. The untreated SA surface demonstrated a rough surface with sharp spikes and deep pits, and the laser produced noticeable changes on the SA titanium surfaces with melting and fusion. The untreated RBM surface demonstrated a rough surface with irregular indentation, and treatment with the laser produced changes on the RBM titanium surfaces. The Er:YAG laser produced significant changes on the roughness parameters, including arithmetic mean height of the surface (Sa) and maximum height of the surface (Sz), of the MA and SA surfaces. However, the Er:YAG laser did not produce notable changes on the roughness parameters, such as Sa and Sz, of the RBM surfaces. Conclusion: This study evaluated the effects of an Er:YAG laser on MA, SA, and RBM titanium discs using confocal microscopy and scanning electron microscopy. Treatment with the laser produced significant changes in the roughness of MA and SA surfaces, but the roughness parameters of the RBM discs were not significantly changed. Further research is needed to evaluate the efficiency of the Er:YAG laser in removing the contaminants, adhering bacteria, and the effects of treatment on cellular attachment, proliferation, and differentiation.

• The Journal of Advanced Prosthodontics
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• v.6 no.4
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• pp.302-308
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• 2014

PURPOSE. The purpose of this study was to compare removal torques and surface topography between laser treated and sandblasted, large-grit, acid-etched (SLA) treated implants. MATERIALS AND METHODS. Laser-treated implants (experimental group) and SLA-treated implants (control group) 8 mm in length and 3.4 mm in diameter were inserted into both sides of the tibiae of 12 rabbits. Surface analysis was accomplished using a field emission scanning electron microscope (FE-SEM; Hitachi S-4800; Japan) under ${\times}25$, ${\times}150$ and ${\times}1,000$ magnification. Surface components were analyzed using energy dispersive spectroscopy (EDS). Rabbits were sacrificed after a 6-week healing period. The removal torque was measured using the MGT-12 digital torque meter (Mark-10 Co., Copiague, NY, USA). RESULTS. In the experimental group, the surface analysis showed uniform porous structures under ${\times}25$, ${\times}150$ and ${\times}1,000$ magnification. Pore sizes in the experimental group were 20-40 mm and consisted of numerous small pores, whereas pore sizes in the control group were 0.5-2.0 mm. EDS analysis showed no significant difference between the two groups. The mean removal torque in the laser-treated and the SLA-treated implant groups were 79.4 Ncm (SD = 20.4; range 34.6-104.3 Ncm) and 52.7 Ncm (SD = 17.2; range 18.7-73.8 Ncm), respectively. The removal torque in the laser-treated surface implant group was significantly higher than that in the control group (P=.004). CONCLUSION. In this study, removal torque values were significantly higher for laser-treated surface implants than for SLA-treated surface implants.

• Journal of Periodontal and Implant Science
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• v.47 no.3
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• pp.182-192
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• 2017

Purpose: Contact and distance osteogenesis occur around all endosseous dental implants. However, the mechanisms underlying these processes have not been fully elucidated. We hypothesized that these processes occur independently of each other. To test this, we used titanium (Ti) tubes to physically separate contact and distance osteogenesis, thus allowing contact osteogenesis to be measured in the absence of possible triggers from distance osteogenesis. Methods: Sandblasted and acid-etched (SLA) and modified SLA (modSLA) implants were used. Both types had been sandblasted with large grit and then etched with acid. The modSLA implants then underwent additional treatment to increase hydrophilicity. The implants were implanted into rabbit tibiae, and half were implanted within Ti tubes. The bone-to-implant contact (BIC) ratio was calculated for each implant. Immunohistochemical analyses of bone morphogenetic protein (BMP)-2 expression and new bone formation (Masson trichrome stain) were performed. Results: The implants outside of Ti tubes were associated with good bone formation along the implant surface. Implantation within a Ti tube significantly reduced the BIC ratio (P<0.001). Compared with the modSLA implants, the SLA implants were associated with significantly higher BIC ratios, regardless of the presence or absence of Ti tubes (P=0.043). In the absence of Ti tubes, the bone adjacent to the implant had areas of new bone formation that expressed BMP-2 at high levels. Conclusions: This study disproved the null hypothesis and suggested that contact osteogenesis is initiated by signals from the old bone that undergoes distance osteogenesis after drilling. This signal may be BMP-2.

• Journal of Periodontal and Implant Science
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• v.41 no.3
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• pp.135-142
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• 2011

Purpose: The present study was performed to evaluate the effect of erbium-doped: yttrium, aluminium and garnet (Er:YAG) laser irradiation on sand-blasted, large grit, acid-etched (SLA) implant surface microstructure according to varying energy levels and application times of the laser. Methods: The implant surface was irradiated by the Er:YAG laser under combined conditions of 100, 140, or 180 mJ/pulse and an application time of 1 minute, 1.5 minutes, or 2 minutes. Scanning electron microscopy (SEM) was used to examine the surface roughness of the specimens. Results: All experimental conditions of Er:YAG laser irradiation, except the power setting of 100 mJ/pulse for 1 minute and 1.5 minutes, led to an alteration in the implant surface. SEM evaluation showed a decrease in the surface roughness of the implants. However, the difference was not statistically Significant. Alterations of implant surfaces included meltdown and flattening. More extensive alterations were present with increasing laser energy and application time. Conclusions: To ensure no damage to their surfaces, it is recommended that SLA implants be irradiated with an Er:YAG laser below 100 mJ/pulse and 1.5 minutes for detoxifying the implant surfaces.

• Journal of Periodontal and Implant Science
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• v.40 no.2
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• pp.69-75
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• 2010

Purpose: Implant survival rates using a bone-added osteotome sinus floor elevation (BAOSFE) procedure with simultaneous placement of a non-submerged sand blasted with large grit and acid etched (SLA) implant are well documented at sites where native bone height is less than 5 mm. This study evaluated the clinical results of non-submerged SLA Straumann implants placed at the time of the BAOSFE procedure at sites where native bone height was less than 4 mm. Changes in graft height after the BAOSFE procedure were also assessed using radiographs for 5 years after the implant procedure. Methods: The BAOSFE procedure was performed on 4 patients with atrophic posterior maxillas with simultaneous placement of 7 non-submerged SLA implants. At least 7 standardized radiographs were obtained from each patient as follows: before surgery, immediately after implant placement, 6 months after surgery, every year for the next 3 years, and after more than 5 years had passed. Clinical and radiographic examinations were performed at every visit. Radiographic changes in graft height were calculated with respect to the implant's known length and the original sinus height. Results : All implants were stable functionally, as well as clinically and radiographically, during the follow-up. Most of the radiographic reduction in the grafted bone height occurred in the first 2 years; reduction after 2 years was slight. Conclusions: The simultaneous placement of non-submerged SLA implants using the BAOSFE procedure is a feasible treatment option for patients with severe atrophic posterior maxillas. However, the grafted bone height is reduced during the healing period, and patients must be selected with care.

• Journal of Periodontal and Implant Science
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• v.49 no.5
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• pp.319-329
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• 2019

Purpose: Direct application of atmospheric-pressure plasma jets (APPJs) has been established as an effective method of microbial decontamination. This study aimed to investigate the bactericidal effect of direct application of an APPJ using helium gas (He-APPJ) on Porphyromonas gingivalis biofilms on sandblasted and acid-etched (SLA) titanium discs. Methods: On the SLA discs covered by P. gingivalis biofilms, an APPJ with helium (He) as a discharge gas was applied at 3 different time intervals (0, 3, and 5 minutes). To evaluate the effect of the plasma itself, the He gas-only group was used as the control group. The bactericidal effect of the He-APPJ was determined by the number of colony-forming units. Bacterial viability was observed by confocal laser scanning microscopy (CLSM), and bacterial morphology was examined by scanning electron microscopy (SEM). Results: As the plasma treatment time increased, the amount of P. gingivalis decreased, and the difference was statistically significant. In the SEM images, compared to the control group, the bacterial biofilm structure on SLA discs treated by the He-APPJ for more than 3 minutes was destroyed. In addition, the CLSM images showed consistent results. Even in sites distant from the area of direct He-APPJ exposure, decontamination effects were observed in both SEM and CLSM images. Conclusions: He-APPJ application was effective in removing P. gingivalis biofilm on SLA titanium discs in an in vitro experiment.

• Analytical Science and Technology
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• v.22 no.3
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• pp.247-253
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• 2009

Porous silicon films are electrochemically etched from crystalline silicon wafers in an aqueous solution of hydrofluoric acid(HF). Careful control of etching conditions (current density, etch time, HF concentration) provides films with precise, reproducible physical parameters (morphology, porosity and thickness). The etched pattern could be varied due to (1) current density controls pore size (2) etching time determines depth and (3) complex layered structures can be made using different current profiles (square wave, triangle, sinusoidal etc.). The optical interference spectrum from Fabry-Perot layer has been used for forensic applications, where changes in the optical reflectivity spectrum confirm the identity. We will explore a method of identifying the specific pattern code and can be used for identities of individual code with porous silicon based encoded nanosized smart particles.

• The Journal of Advanced Prosthodontics
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• v.16 no.3
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• pp.189-199
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• 2024

PURPOSE. This study was conducted to evaluate the effects of plasma treatment of sandblasted and acid-etched (SLA) titanium implants on surface cleansing and osseointegration in a beagle model. MATERIALS AND METHODS. For morphological analysis and XPS analysis, scanning electron microscope and x-ray photoelectron spectroscopy were used to analyze the surface topography and chemical compositions of implant before and after plasma treatment. For this animal experiment, twelve SLA titanium implants were divided into two groups: a control group (untreated implants) and a plasma group (implants treated with plasma). Each group was randomly located in the mandibular bone of the beagle dog (n = 6). After 8 weeks, the beagle dogs were sacrificed, and volumetric analysis and histometric analysis were performed within the region of interest. RESULTS. In morphological analysis, plasma treatment did not alter the implant surface topography or cause any physical damage. In XPS analysis, the atomic percentage of carbon at the inspection point before the plasma treatment was 34.09%. After the plasma treatment, it was reduced to 18.74%, indicating a 45% reduction in carbon. In volumetric analysis and histometric analysis, the plasma group exhibited relatively higher mean values for new bone volume (NBV), bone to implant contact (BIC), and inter-thread bone density (ITBD) compared to the control group. However, there was no significant difference between the two groups (P > .05). CONCLUSION. Within the limits of this study, plasma treatment effectively eliminated hydrocarbons without changing the implant surface.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.559-568
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• 1996

The purpose of this study was to evaluate the micro leakage of composite resin when various phosphoric acid agents were used to etch the enamel and dentin. In this study, class V cavities were prepared on the buccal surfaces of fourty extracted human molar teeth, and they were randomly assigned into 4 groups with 10 teeth. The cavities of each groups were etched with 10%, 32%, 35% and 37% phosphoric acids for 15 seconds, washed and dried and the cavities were restored with composite resin after application of the adhesive. The specimens were immersed in 2% methylene blue solution for 3 days. And then, the specimens were sectioned buccoligually. Degree of dye penetration at tooth-restoration interfaces was examined by Inverted Metallurgical Microscope at the occlusal and gingival margins. The result were as follows : 1. The degree of microleakage at occlusal and gingival margin in all group was statistically difference among 10% and 35% (P<0.01), 10% and 37% (P<0.01), 32% and 35% (P<0.05) and 32% and 37% (P<0.05) acid concentrations, but was not statistically difference between 10% and 32%, 35% and 37% acid concentrations (P>0.05). The degree of microleakage was showed to dimish with increase of acid concentration. 2. The degree of microleakage at the occlusal margin was statistically significant difference among 10% and 32%,10% and 35%, 10% and 37% acid concentrations(P<0.05). The degree of microleakage among 32% and 35%, 32% and 37% and 32% and 37% acid concentrations was not statistically significant difference. 3. In comparison of microleakage at the gingival margin, the degree of microleakage above 32% acid concentration was not showed less than 10% acid concentration (P>0.05). In comparison of 32%, 35%, 37% acid concentrations, the degree of microleakage at 35% and 37% acid concentrations was showed less than 32% acid concentration(P<0.05).