Magnesium substituted hydroxyapatite (Mg-HA) thin films were prepared using an rf-magnetron sputtering method. The Mg-HA films were coated onto titanium (Ti) substrates from mixed HA/MgO powder targets. The ratio of Mg / (Mg + Ca) of the target was varied in the ratio of 5, 10, 20, 40, 60 and 80%. The coated films were crystallized by a hydrothermal treatment to reduce the dissolution rate of the films. In the determination of the chemical compositions of the Mg-HA films before and after the hydrothermal treatment, the films were dissolved in an acid solution, and the solutions were measured by inductively coupled plasma mass spectrometry (ICP-MS). The bone formation of the films was evaluated by the bone formation area of osteoblast cells. The chemical analysis showed Mg concentration of the films increased with the ratio of Mg / (Mg + Ca) of the target, but the Mg concentration decreased after the hydrothermal treatment. In the cell culture, the bone formation area on the Mg-HA films decreased with increasing Mg concentration of the films.

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Local irrigation using ozone nano-bubble water (NBW3) with high anti-bacterial/cleaning effect and the mouthwash method are applied clinically for the prevention of postoperative infection after implant surgery. The present study investigated the optimal mouth washing time for killing Streptococcus mutans, initial colonizers of biofilm formation when mouth washing using NBW3. In addition, a commercially available mouthwash (chlorhexidine gluconate solution) was used to comparatively review both antibacterial effects. The results showed that the decrease rate of viable bacteria using NBW3 had reduced to less than about 10% and 1%, respectively, for 5 and 10 seconds, and to less than the detection limits in the present study for 30 and 60 seconds. Also, that of viable bacteria using a chlorhexidine gluconate solution had reduced to about 92, 81, 77, and 58%, respectively, for 5, 10, 30, and 60 seconds. The results showed higher antibacterial activity of NBW3 in each duration of activity compared with ConCool F® (chlorhexidine gluconate solution) under the same conditions of the present study. The results of the present study suggest that mouth washing using NBW3 might kill intraoral bacteria more efficiently compared with using a mouthwash solution.

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Purpose: Prognosis of dental implant therapy after placement is commonly dependent on the efficient bonding of titanium implant and jaw bone. Simvastatin (SIM), which is a classic antihyperlipidemic drug, has been remarkably attracted in dental region since it was reported that SIM has bone regeneration effect, and thus, SIM has been expected as the compound to support dental implant therapy. In this study, we aimed for the development of simvastatin-loaded gelatin/hydroxyapatite spherical granules (SIM/GE/HAP) using spheronizer (Marumerizer) for efficient dental implant therapy. Methods: Preparation of SIM/GE/HAP: SIM/GE/HAP was prepared using spheronizer for producing on a large scale. Characterization of SIM/GE/HAP: The surface morphology of the SIM/GE/HAP was visualized using a scanning electron microscope. In vitro drug release in phosphate buffered saline (PBS) or simulated body fluid (SBF): The SIM/GE/HAP was determined by UV-VIS spectrometer. To understand the mechanism of SIM release from the SIM/GE/HAP, the results of in vitro release profiles were fitted to a mathematical model. The X-ray powder diffraction (XRD) profile of SIM/GE/HAP was measured by powder X-ray diffractometer to evaluate the composition and crystallinity of the granules before and after in vitro release test. Results: The SIM/GE/HAP in SBF exhibited sustainable release profile for 1 week. In contrast, the SIM/GE/ HAP in PBS released SIM approximately 60% within 1 week. These results mean that SIM/GE/HAP implanted in the body can release SIM until the implant is attached with jaw bone. The XRD spectrum of SIM/GE/HAP after the release test in SBF was characteristics of HAP. On the other hand, The XRD spectrum of SIM/GE/ HAP after the release test in PBS showed most parts of granule bulk did not transform into HAP. Conclusion: The results showed that SIM/GE/HAP prepared using spheronizer could release SIM continuously and has a potential to promote the local bone regeneration. Keywords: Bone regeneration, Simvastatin, Hydroxy apatite, Drug delivery system, Controlled release

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Objective: The aim of this was to evaluate the metal artifacts on AZ3000CT images using the titanium cylinders in relation to different exposure protocols. Materials and method: The titanium cylinders were fabricated for the evaluation of metal artifacts. The cylinders heights were 15.07 mm and 15.06 mm, and the diameters were 3.49 mm, and 2.99 mm were installed at the anterior and posterior side of the plastic model mandible, respectively. The cylinders positions were in two central incisors for anterior and molar regions for the posterior segment, and the cylinders were placed 10 mm from each other. CBCT examinations were performed with AZ3000CT, FPD type (Asahi Roentgen ltd, Kyoto, Japan). The titanium cylinders were imaged at the same position at tube voltages of 60 and 90 kV, 4mA, and 17 seconds. The heights of the cylinders were measured in coronal and sagittal images. Diameter measurement was performed at the center of the cylinder. The anteroposterior (AP) and mediolateral (ML) diameters of cylinders were measured in axial images. All data were evaluated with the Image J and OsiriX image analysis software. Results: In the measurement of the heights of the titanium cylinders, the mean heights deviated from 102.32% to 102.72%, and 100.53% to 100.86 % for a single cylinder for 60 and 90 kV, respectively. For double cylinders, the mean heights were from 101.32% to 102.52%, and 100.99% to 102.05% for 60 and 90 kV, respectively. The mean diameters AP and ML were (104.34% to 104.68%, and 102.29% to 103.34%; and 103.67% to 104.01%, and 101.14% to 102.67%) for a single cylinder for 60 and 90 kV, respectively. For double cylinders, the mean diameters AP and ML were (103.82% to 104.29%, and 103.15% to 104.34%; and 103.43% to 104.01%, and 102.00% to 103.34%) for 60 and 90 kV, respectively. Conclusion: Artifacts can damage the quality of images, sometimes causing unusable in the diagnosis. It originates from an assortment of some sources, including the presence of metallic materials and patient positioning. However, it is necessary to evaluate preoperatively metal artifacts for successful Implant installation. Keywords: cone beam CT, titanium cylinder, artifact.

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The implant treatment has been popularly performed as one of the missing prosthesis. The usefulness is clinically proven in the fields of dentistry. However, on the other hand, lacks in aesthetics and function, and severe accidents such as paralysis or vascular injury have been reported. There is an implant method using a computer assisted surgery guide to avoid these problems. In this case study we have evaluated the accuracy of the clinical results with using the surgical guide and without the surgical guide that is in free hand. As a result the surgical guide was useful to safely carry out implant treatment.

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Recentry, the opportunity, which the ceramic materials such as zirconia and lithium disilicate are used as the material of the abutments and superstructure, has been increased. This is because they are better in esthetics and biocompatibility as compared to titaniums. Because each of these ceramic materials has both advantages and disadvantages, it is necessary to distinguish on a case-by-case basis. Three cases of the implant prosthesis, in which zirconia and lithium disilicate are used are reported and discussed.

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We revealed that the effect of osseointegration to titanium implant by UVC irradiation is weakened in a relatively short time in the air. As a result of considering the environment that can keep longer the effect of UVC irradiation, it was found that the effect was kept 18months by being saved the implants in a liquid, such as purified water or saline immediately after UVC irradiation. This time we report the three clinical cases supporting these.

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HA coated one-piece implants have been clinically applied, and can be obtaining a good prognosis. However, onepiece implant is pointed out that it is difficult to obtain aesthetic restoration. One of the reasons is considered that it is difficult to establish both the aesthetic repair and hygiene management. In this paper, we introduce that an easy technique to obtain the aesthetic and hygienic prosthetic restoration for one-piece implant using the standardized implant body abutment and the data based on CAD/CAM system.

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