Publications by authors named "Heng Bo Jiang"

16 Publications

  • Page 1 of 1

Corrosion Evaluation of Pure Mg Coated by Fluorination in 0.1 M Fluoride Electrolyte.

Scanning 2021 13;2021:5574946. Epub 2021 May 13.

The Conversationalist Club, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

In the ongoing research on the application of biodegradable materials, surface treatment of is considered to be a relatively effective solution to the excessive degradation rates of Mg alloys. In this study, to further optimize the proven effective surface coatings of fluoride, a low-voltage preparation fluorination method was used to achieve coating effectiveness under safer conditions. Optical observation, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and potential dynamic polarization (PDP) experiments were used for the analysis and evaluation. The coating characteristics of the MgF coatings treated in the 10-90 V voltage range, including the structure, chemical conformation, and electrochemical corrosion assessment, were fully defined. The anodic fluoridation results showed that a pore structure of 1-14 m thickness was formed on the Mg alloy substrate, and the coating was composed of Mg fluoride. The results of immersion corrosion and electrochemical corrosion experiments showed that compared with pure Mg, anodic fluorinated samples below 40 V exhibited better corrosion resistance, the prepared MgF coating was more uniform, and the surface mostly exhibited point corrosion. When the voltage reached or exceeded 60 V, the prepared coating exhibited poor corrosion resistance, fracture, and protrusions. After corrosion, it mostly exhibited surface corrosion. The results indicate that idealized coatings can be obtained at relatively low and safe voltage ranges. This finding may enable more economical, environmentally friendly, and safe preparation of coatings.
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http://dx.doi.org/10.1155/2021/5574946DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8140829PMC
June 2021

Corrosion Behavior of Biodegradable Magnesium Alloy by MAF Treatment.

Scanning 2021 3;2021:5530788. Epub 2021 May 3.

The Conversationalist Club, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

Coating treatment plays an irreplaceable role in propelling the clinical application of magnesium alloys. This experiment was designed in order to observe the anticorrosion behavior of magnesium fluoride coating in rats. The MgF layer was prepared on the surface of AZ31 magnesium alloy in saturated NHHF solution by microarc fluorination (MAF) at 190 V. The cross-sectional SEM, EDS, and XRD analysis indicated that the alloy surface was covered with MgF. Meanwhile, SEM observation was used to compare the magnesium alloy samples before and after treatment, and it was found that the samples after coating were flatter and smoother. Two sets of experiments were carried out with the subjects, 6-week-old male rats. So that the untreated AZ31 samples and the microarc fluorinated AZ31 samples could be buried under the muscle layer individually. The volume changes and surface morphology of the corroded samples were monitored dynamically using micro-CT over a 16-week period . Comparison of results between the two sets of samples presented that the corrosion of the microarc fluoridated samples was much slower than that of the untreated ones. The MAF coating was shown to be effective in controlling the corrosion rate and progression of the magnesium alloy.
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http://dx.doi.org/10.1155/2021/5530788DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8112943PMC
May 2021

Comparison of Autogenous Tooth Materials and Other Bone Grafts.

Tissue Eng Regen Med 2021 Jun 30;18(3):327-341. Epub 2021 Apr 30.

Department of Oral and Maxillofacial Surgery, Graduate School of Clinical Dentistry, Korea University, Seoul, 02841, Republic of Korea.

Autogenous odontogenic materials are a new, highly biocompatible option for jaw restoration. The inorganic component of autogenous teeth acts as a scaffold to maintain the volume and enable donor cell attachment and proliferation; the organic component contains various growth factors that promote bone reconstruction and repair. The composition of dentin is similar to that of bone, which can be a rationale for promoting bone reconstruction. Recent advances have been made in the field of autogenous odontogenic materials, and studies have confirmed their safety and feasibility after successful clinical application. Autogenous odontogenic materials have unique characteristics compared with other bone-repair materials, such as the conventional autogenous, allogeneic, xenogeneic, and alloplastic bone substitutes. To encourage further research into odontogenic bone grafts, we compared the composition, osteogenesis, and development of autogenous odontogenic materials with those of other bone grafts. In conclusion, odontogenic bone grafts should be classified as a novel bone substitute.
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http://dx.doi.org/10.1007/s13770-021-00333-4DOI Listing
June 2021

Effects of Physical Stimulation in the Field of Oral Health.

Scanning 2021 7;2021:5517567. Epub 2021 Apr 7.

Stomatological Materials Laboratory, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

Physical stimulation has been widely used in clinical medicine and healthcare due to its noninvasiveness. The main applications of physical stimulation in the oral cavity include laser, ultrasound, magnetic field, and vibration, which have photothermal, cavitation, magnetocaloric, and mechanical effects, respectively. In addition, the above four stimulations with their unique biological effects, which can play a role at the gene, protein, and cell levels, can provide new methods for the treatment and prevention of common oral diseases. These four physical stimulations have been used as important auxiliary treatment methods in the field of orthodontics, implants, periodontal, dental pulp, maxillofacial surgery, and oral mucosa. This paper systematically describes the application of physical stimulation as a therapeutic method in the field of stomatology to provide guidance for clinicians. In addition, some applications of physical stimulation in specific directions are still at the research stage, and the specific mechanism has not been fully elucidated. To encourage further research on the oral applications of physical stimulation, we elaborate the research results and development history of various physical stimuli in the field of oral health.
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http://dx.doi.org/10.1155/2021/5517567DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8049832PMC
April 2021

Design of a Single-Tooth Model and Its Application in Oral Scan System Assessment.

Scanning 2021 21;2021:8891396. Epub 2021 Mar 21.

Stomatological Materials Laboratory, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

Intraoral scanners have been widely used in the application of dentistry. Accuracy includes trueness and precision; they have an important position in the assessment of intraoral scanners. The existing standard models are divided into the inlay and the crown, but the operation is relatively complicated. In this study, in order to simplify the current standard model, we designed a new integration model to compare the accuracy of two intraoral scanners (CEREC and TRIOS) and an extraoral scanner (SHINING). The coordinate measuring machine measured value is the gold standard. Values of the length and angle were analyzed by converting the scanned digital impressions into an STL (standard triangulation language) format to evaluate the accuracy of the intraoral scanner and to verify the feasibility of the designed model. The result shows that the integration model can be successfully scanned and imaged. In the case of the powder-free integration model, intraoral scanner precision, trueness, 3D fitting, and imaging are better than the extraoral scanner. It can be seen straightly from the measurement result and the 3D fitting result that the intraoral scanner can acquire the shape of the standard model integrally with good repeatability. Therefore, it can be concluded that TRIOS is superior to CEREC and SHINING in accuracy, and the integration model is feasible as a reference in the examination of intraoral scanners. The performance of the newly designed integration model that can be scanned is clinically significant, suggesting that this model can be used as a standard reference model.
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http://dx.doi.org/10.1155/2021/8891396DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009709PMC
March 2021

Accuracy and Precision Evaluation of International Standard Spherical Model by Digital Dental Scanners.

Scanning 2020 9;2020:1714642. Epub 2020 Dec 9.

Stomatological Materials Laboratory, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

With the popularization of digital technology and the exposure of traditional technology's defects, computer-aided design and computer-aided manufacturing (CAD/CAM) has been widely used in the field of dentistry. And the accuracy of the scanning system determines the ultimate accuracy of the prosthesis, which is a very important part of CAD/CAM, so we decided to evaluate the accuracy of the intraoral and extraoral scanners. In this study, we selected the sphere model as the scanning object and obtained the final result through data analysis and 3D fitting. In terms of trueness and precision, the scanner of SHINING was significantly different from that of others; however, there was no significant difference between TRIOS and CEREC. SHINING showed the lowest level of accuracy, with CEREC slightly lower than TRIOS. The sphere model has also been proven to be scanned successfully.
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http://dx.doi.org/10.1155/2020/1714642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787873PMC
December 2020

Research of weak interaction between water and different monolayer graphene systems.

J Mol Graph Model 2021 05 5;104:107835. Epub 2021 Jan 5.

Stomatological Materials Laboratory, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong, 271016, China. Electronic address:

Weak interactions play a very important role in the fields of supramolecular chemistry, molecular physics, materials science, etc. They have a great impact on the structure of the compounds in the gas, liquid and solid phases and the mechanism of some reaction processes. In this study, we visualized the intermolecular interactions between HO and different graphene systems through density functional theory. Because the surface of Graphene oxide (GO) has epoxy groups, hydroxyl groups, and other oxygen-containing groups. These groups are prone to hydrogen bonding with hydrogen atoms of HO, and we further explain some of them based on the acid-base theory. Also, we obtained the components of interactions between different graphene complex and HO by energy decomposition. Then we found that for systems with moderate strength hydrogen bonding, such as hydroxyl functional group systems, electrostatic attraction is dominant while the dispersion attraction and induction function play an auxiliary role together.
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http://dx.doi.org/10.1016/j.jmgm.2021.107835DOI Listing
May 2021

Surface Characterization and Corrosion Resistance of Biomedical AZ31 Mg Alloy Treated by Microarc Fluorination.

Scanning 2020 27;2020:5936789. Epub 2020 Oct 27.

Department of Oral and Maxillofacial Surgery, Graduate School of Clinical Dentistry, Korea University, Seoul 08308, Republic of Korea.

The application prospect of biodegradable materials is being studied extensively. However, the high corrosion rate and its alloys in body fluids have been major limitations of the application of pure Mg (magnesium). To improve corrosion resistance of biodegradable AZ31 Mg alloy, we adopted microarc fluorination within a voltage range of 100-300 V in 46% hydrofluoric acid. To obtain morphologies, chemical compositions, and structural characteristics, field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) were performed, respectively. Results showed that the coating was mainly composed of MgF. Electrochemical corrosion and immersion tests proved that the corrosion resistance of MAF-treated AZ31 Mg alloy was significantly improved compared with untreated AZ31 Mg alloy in HBSS (Hank's Balanced Salt Solution). Current densities of AZ31, MAF100, MAF150, MAF200, MAF250, and MAF300 were 342.4, 0.295, 0.228, 0.177, 0.199, and 0.212 A/cm, respectively. The roughness test indicated that samples under MAF treatment of 200 V, 250 V, and 300 V had large surface roughness. Meanwhile, the contact angle measurement and surface free energy test suggested that those samples had smaller contact angle and higher SFE than Ti. Thus, MAF-treated AZ31 Mg alloy might have promising application in various fields.
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http://dx.doi.org/10.1155/2020/5936789DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7641723PMC
October 2020

Characterization of a Bioresorbable Magnesium-Reinforced PLA-Integrated GTR/GBR Membrane as Dental Applications.

Scanning 2020 19;2020:6743195. Epub 2020 Sep 19.

Stomatological Materials Laboratory, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

Inferior mechanical properties have always been a limitation of the bioresorbable membranes in GBR/GTR. This study is aimed at fabricating a bioresorbable magnesium-reinforced polylactic acid- (PLA-) integrated membrane and investigating its mechanical properties, degradation rate, and biocompatibility. The uncoated and fluoride-coated magnesium alloys, AZ91, were made into strips. Then, magnesium-reinforced PLA-integrated membrane was made through integration. PLA strips were used in the control group instead of magnesium strips. Specimens were cut into rectangular shape and immersed in Hank's Balanced Salt Solution (HBSS) at 37°C for 4, 8, and 12 d. The weight loss of the AZ91 strips was measured. Three-point bending tests were conducted before and after the immersion to determine the maximum load on specimens. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) were conducted on coated and uncoated AZ91 plates to examine corrosion resistance. Murine fibroblast and osteoblast cells were cultured on circular specimens and titanium disks for 1, 3, and 5 d. Thereafter, WST test was performed to examine cell proliferation. As a result, the coated and uncoated groups showed higher maximum loads than the control group at all time points. The weight loss of AZ91 strips used in the coated group was lower than that in the uncoated group. PDP, EIS, SEM, and EDS showed that the coated AZ91 had a better corrosion resistance than the uncoated AZ91. The cell proliferation test showed that the addition of AZ91 did not have an adverse effect on osteoblast cells. Conclusively, the magnesium-reinforced PLA-integrated membrane has excellent load capacity, corrosion resistance, cell affinity, and proper degradation rate. Moreover, it has great potential as a bioresorbable membrane in the GBR/GTR application.
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http://dx.doi.org/10.1155/2020/6743195DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7520691PMC
September 2020

Bioresorbable magnesium-reinforced PLA membrane for guided bone/tissue regeneration.

J Mech Behav Biomed Mater 2020 12 26;112:104061. Epub 2020 Aug 26.

Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul, 03722, Republic of Korea; BK21 PLUS Project, Yonsei University College of Dentistry, Seou, 03722, Republic of Korea. Electronic address:

Considering the inferior mechanical properties of the current bioresorbable polymers, a novel bioresorbable magnesium-reinforced polylactide (PLA) membrane was designed for the application in critical defect sites in guided bone/tissue regeneration. The PLA-FAZ91 membrane was fabricated by combining two PLA membranes with a fluoride-coated AZ91 (9 wt% Al, 1 wt% Zn) (FAZ91) magnesium alloy core by hot pressing. A combined double-layered PLA membrane was used as the control group. A three-point bending test was performed to compare their maximum load and stiffness. Samples were immersed in the HBSS for 20 weeks, and their weight loss percentages were recorded, and a three-point bending test was performed after immersion. An ion release test was performed by immersing samples in the HBSS for 4 weeks and determining the pH and ion concentrations of the HBSS. Cell viability was tested by culturing pre-osteoblast cells with sample extracts in the culture medium obtained from degraded samples. As a result, PLA-FAZ91 showed a significantly higher maximum load and stiffness than those of the non-reinforced PLA membrane. The weight loss of PLA-FAZ91 was much faster, as FAZ91 showed major degradation and was completely degraded after 16-20 weeks of immersion. The degradation of the PLA wrap was accelerated by FAZ91. The mechanical superiority of PLA-FAZ91 over PLA endured for at least 3 weeks during immersion. The pH, magnesium- and fluoride-ion concentration in the PLA-FAZ91 group increased at an appropriate rate. The cell viability was not adversely affected by the addition of FAZ91 to PLA. Therefore, the bioresorbable magnesium-reinforced PLA membrane has the potential to be used as a good alternative to pure PLA membrane in guided bone/tissue regeneration.
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http://dx.doi.org/10.1016/j.jmbbm.2020.104061DOI Listing
December 2020

Comparing Properties of Variable Pore-Sized 3D-Printed PLA Membrane with Conventional PLA Membrane for Guided Bone/Tissue Regeneration.

Materials (Basel) 2019 May 27;12(10). Epub 2019 May 27.

Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Korea.

The aim of this study was to fabricate bioresorbable polylactide (PLA) membranes by 3D printing and compare their properties to those of the membranes fabricated by the conventional method and compare the effect of different pore sizes on the properties of the 3D-printed membranes. PLA membranes with three different pore sizes (large pore-479 μm, small pore-273 μm, and no pore) were 3D printed, and membranes fabricated using the conventional solvent casting method were used as the control group. Scanning electron microscopy (SEM) and micro-computed tomography (µ-CT) were taken to observe the morphology and obtain the porosity of the four groups. A tensile test was performed to compare the tensile strength, elastic modulus, and elongation at break of the membranes. Preosteoblast cells were cultured on the membranes for 1, 3 and 7 days, followed by a WST assay and SEM, to examine the cell proliferation on different groups. As a result, the 3D-printed membranes showed superior mechanical properties to those of the solvent cast membranes, and the 3D-printed membranes exhibited different advantageous mechanical properties depending on the different pore sizes. The various fabrication methods and pore sizes did not have significantly different effects on cell growth. It is proven that 3D printing is a promising method for the fabrication of customized barrier membranes used in GBR/GTR.
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http://dx.doi.org/10.3390/ma12101718DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6566256PMC
May 2019

The antibacterial effect of non-thermal atmospheric pressure plasma treatment of titanium surfaces according to the bacterial wall structure.

Sci Rep 2019 02 13;9(1):1938. Epub 2019 Feb 13.

BK21 PLUS Project, Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul, 03722, Korea.

Titanium is commonly used as a biomaterial for dental implants. In this study, we investigated the antibacterial properties of titanium samples following treatment with a non-thermal atmospheric pressure plasma jet (NTAPPJ) on bacteria with two different cell wall structures, including gram-positive and gram-negative bacteria. The hydrophilicity and surface energy of titanium surfaces were significantly increased after NTAPPJ treatment without altering topographical features. Changes in the chemical composition and reductive potential were observed on the NTAPPJ-treated titanium surfaces. The adhesion and biofilm formation rate of bacteria were significantly reduced on the NTAPPJ-treated titanium surfaces compared with the untreated samples, which was confirmed by fluorescent imaging. Regarding the comparison between gram-positive and gram-negative bacteria, both adhesion and the biofilm formation rate were significantly lower for gram-negative bacteria than gram-positive bacteria on samples treated for longer durations with the NTAPPJ. Transmission electron microscopy imaging showed a comparably more disruptive membrane structure of gram-negative bacteria than gram-positive bacteria on the NTAPPJ-treated surfaces. Our results indicated that the NTAPPJ treatment could be useful for preventing bacterial adhesion and biofilm formation on titanium dental implant surfaces, while the reductive potential on surfaces treated by the NTAPPJ could cause oxidation of bacteria, which could be more sensitive to gram-negative bacteria due to differences in the cell wall structure.
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http://dx.doi.org/10.1038/s41598-019-39414-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6374442PMC
February 2019

Hydrogen-rich water ameliorates rat placental stress induced by water restriction.

Med Gas Res 2018 Jul-Sep;8(3):79-84. Epub 2018 Sep 25.

Key Laboratory of Atherosclerosis in Universities of Shandong and Institute of Atherosclerosis, Taishan Medical University, Taishan, Shandong Province, China.

Dehydration is one of the intrauterine abnormalities that could lead to fetal growth retardation and to increase the risk of a variety of adult diseases later in life. This study were to determine the impact of hydrogen-rich water (HRW) supplementation on placental angiotensin II type 1 receptor and placental oxidative stress induced by water restriction. Pregnant Wistar rat were randomly assigned to one of the three groups ( =12 per group). In control group, pure water and food were supplied ad libitum. Water restriction group and HRW group were respectively given pure water and HRW with free access to food, excepting only one hour was available for drinking from day 7 to day 17 of pregnancy. The placental damages and biomarkers of stress were detected by histopathology, immunohistochemistry and western blot, as well as serological test were performed. We demonstrated that maternal water restriction resulted in reduced urine volume and increased serum osmotic pressure, along with decreased fetus weight and crown-rump length. Although placental weight and the number of fetuses had no significant difference among groups, the placental efficiency significantly increased after the oral administration of HRW to the mothers. Meanwhile, the serological derivatives of reactive oxygen metabolites decreased, a significant improvement of placental microstructure with more developed junctional zone and denser labyrinth was manifested, the upregulated expression of angiotensin II type 1 receptor, nuclear factoκB, malondialdehyde, 8-hydroxydeoxyguanosine, p38, c-Jun N-terminal kinase and down-regulation of superoxide dismutase were revealed in the placenta. Collectively, HRW administration is able to effectively attenuate placental stress induced by water restriction.
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http://dx.doi.org/10.4103/2045-9912.241064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6178645PMC
September 2018

Effects of thermoforming on the physical and mechanical properties of thermoplastic materials for transparent orthodontic aligners.

Korean J Orthod 2018 Sep 8;48(5):316-325. Epub 2018 Aug 8.

Department and Research Institute for Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul, Korea.

Objective: The aim of this systematic multiscale analysis was to evaluate the effects of thermoforming on the physical and mechanical properties of thermoplastic materials used to fabricate transparent orthodontic aligners (TOAs).

Methods: Specimens were fabricated using four types of thermoplastic materials with different thicknesses under a thermal vacuum. Transparency, water absorption and solubility, surface hardness, and the results of three-point bending and tensile tests were evaluated before and after thermoforming. Data were analyzed using one-way analysis of variance and Student's -test.

Results: After thermoforming, the transparency of Duran and Essix A+ decreased, while the water absorption ability of all materials; the water solubility of Duran, Essix A+, and Essix ACE; and the surface hardness of Duran and Essix A+ increased. The flexure modulus for the 0.5-mm-thick Duran, Essix A+, and eCligner specimens increased, whereas that for the 0.75-/1.0-mm-thick Duran and eClginer specimens decreased. In addition, the elastic modulus increased for the 0.5-mm-thick Essix A+ specimens and decreased for the 0.75-mm-thick Duran and Essix ACE and the 1.0-mm-thick Essix ACE specimens.

Conclusions: Our findings suggest that the physical and mechanical properties of thermoplastic materials used for the fabrication of TOAs should be evaluated after thermoforming in order to characterize their properties for clinical application.
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http://dx.doi.org/10.4041/kjod.2018.48.5.316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6123073PMC
September 2018

The effect of fluoride-containing oral rinses on the corrosion resistance of titanium alloy (Ti-6Al-4V).

Korean J Orthod 2017 Sep 27;47(5):306-312. Epub 2017 Jul 27.

Department of Orthodontics, The Institute of Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea.

Objective: The purpose of this study was to examine the effect of commercially available fluoride-containing oral rinses on the corrosion behavior of titanium alloys, which are the main components of orthodontic miniscrews.

Methods: Four commercially available oral rinses (solution A, pH 4.46/260 ppm fluoride; solution B, pH 4.41/178 ppm fluoride; solution C, pH 6.30/117 ppm fluoride; and solution D, pH 4.17/3.92 ppm fluoride) were tested on titanium alloy (Ti-6Al-4V) circular plates, and saline was used as the control. The open-circuit potential and potentiodynamic polarization of these materials were measured. Thereafter, all samples were evaluated under a field-emission scanning electron microscope.

Results: Among the tested oral rinses, except solution D, the more the fluoride content was, the greater was the corrosion potential downtrend; the corrosion resistance of the titanium alloy sample was also lowered significantly ( < 0.05). Field-emission scanning electron microscopic analysis of the surface morphology of the titanium alloy samples revealed that all samples had some defects, crevices, or pitting after exposure to the oral rinses than before treatment. In particular, the samples in solution A showed the most changes.

Conclusions: Commercially available oral rinses having a high fluoride concentration and a low pH may reduce the corrosion resistance of titanium alloys used in dental appliances such as orthodontic titanium miniscrews and brackets.
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http://dx.doi.org/10.4041/kjod.2017.47.5.306DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5548711PMC
September 2017

Evaluation of the accuracy and precision of four intraoral scanners with 70% reduced inlay and four-unit bridge models of international standard.

Dent Mater J 2017 Jan 6;36(1):27-34. Epub 2016 Dec 6.

Department and Research Institute of Dental Biomaterials and Bioengineering, College of Dentistry, Yonsei University.

The aims of this study were to evaluate the feasibility of 70% reduced inlay and 4-unit bridge models of International Standard (ISO 12836) assessing the accuracy of laboratory scanners to measure the accuracy of intraoral scanner. Four intraoral scanners (CS3500, Trios, Omnicam, and Bluecam) and one laboratory scanner (Ceramill MAP400) were used in this study. The height, depth, length, and angle of the models were measured from thirty scanned stereolithography (STL) images. There were no statistically significant mean deviations in distance accuracy and precision values of scanned images, except the angulation values of the inlay and 4-unit bridge models. The relative errors of inlay model and 4-unit bridge models quantifying the accuracy and precision of obtained mean deviations were less than 0.023 and 0.021, respectively. Thus, inlay and 4-unit bridge models suggested by this study is expected to be feasible tools for testing intraoral scanners.
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http://dx.doi.org/10.4012/dmj.2016-064DOI Listing
January 2017