Yasutomo Yajima

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BACKGROUND Antimicrobial proteins are abundant in saliva. The purpose of this study was to determine and compare the amounts of two types of antibacterial protein, cystatin and lysozyme, in saliva between healthy persons and subjects with periodontitis. METHODS Forty subjects with periodontitis visiting Tokyo Dental College Chiba Hospital, Chiba, Japan,(More)
Periodontal disease is considered a risk factor in dental implant treatment. The purpose of this study was to investigate the periodontal conditions in patients requesting dental implant therapy. A total of 169 patients visiting Department of Oral and Maxillo-Facial Implantology at Tokyo Dental College Chiba Hospital were targeted. The following intraoral(More)
The purpose of this study was to investigate digital subtraction technique in digital dental imaging for implant performance, used to quantitatively evaluate bone change around dental implants. For longitudinal assessment of peri-implant bone change, we applied subtraction technique to digital peri-apical radiographs using a digital dental imaging system in(More)
Cone-beam CT (CBCT) systems specifically designed for hard-tissue imaging of the maxillofacial region have recently become commercially available. The newly-developed CBCT system, CB Throne (Hitachi Medical Corp., Tokyo), is characterized by a number of features such as low dose, sub-millimeter spatial resolution, and a small footprint. This system has been(More)
The objective of this study was to clarify the effect of surface topography on osteoblast-like cell behavior on yttria stabilized tetragonal zirconia polycrystals (TZP). Mirror-polished; blasted with 50- or 150-µm alumina (SB50 and SB150); and SB150 acid-etched with hydrofluoric acid (SB150E) were prepared on TZP. Initial attachment, proliferation and(More)
The aim of this study was to clarify the influence of tetragonal zirconia polycrystal (TZP) on the two-body wear behavior of titanium (Ti). Two-body wear tests were performed using TZP, two grades of cp-Ti or Ti alloy in distilled water, and the cross-sectional area of worn surfaces was measured to evaluate the wear behavior. In addition, the surface(More)
We observed surfaces and cross sections of thin hydroxyapatite (HA)-coated implants produced by the thermal decomposition method in a patient attending our clinic who underwent implant removal at 80 months due to fracture of the implants. On the implant surfaces of the removed sample, most of the HA had dissolved, and extensive osseointegration was observed(More)
Symptoms of Systemic Inflammatory Response Syndrome (SIRS) presenting immediately after surgery have lately been regarded as potential warnings of impending postoperative complications and multiple organ failure. Reports discussing the relationship between operative stress and SIRS are found in the field of digestive surgery, but not in that of oral(More)
PURPOSE Prevention of peri-implantitis is essential for the success of implant rehabilitation. Infection by periodontopathic bacteria is a major cause of peri-implantitis. The aim of the present study was to identify the source of peri-implant colonization by periodontopathic bacteria. MATERIALS AND METHODS Twenty-one patients with implants were enrolled(More)
Hot isostatic pressing processed yttria-stabilized tetragonal zirconia polycrystal (HIP Y-TZP) has the potential for application to implants due to its high mechanical performance. The aim of this study was to investigate the influence of surface treatment of HIP Y-TZP on cyclic fatigue strength. HIP Y-TZP specimens were subjected to different surface(More)