We investigated the prevalences and risk factors for peri-implant diseases in Japanese adult dental patients attending a follow-up visit at dental hospitals or clinics as part of their maintenance program. This cross-sectional multicenter study enrolled patients with dental implants who attended regular check-ups as part of a periodontal maintenance program during the period from October 2012 through September 2013. Patients with implants with at least 3 years of loading time were included in the study. The condition of peri-implant tissue was examined and classified into the following categories: healthy, peri-implant mucositis, and peri-implantitis. Patients were also evaluated for implant risk factors. A total of 267 patients (110 men, 157 women; mean age: 62.5 ± 10.7 years) were analyzed. The prevalence of patient-based peri-implant mucositis was 33.3% (n = 89), and the prevalence of peri-implantitis was 9.7% (n = 26). Poor oral hygiene and a history of periodontitis were strong risk factors for peri-implant disease. The present prevalences were lower than those previously reported. The quality of periodontal therapy before and after implant installation and patient compliance and motivation, as indicated by plaque control level, appear to be important in maintaining peri-implant tissue health.

：The purpose of this study was to investigate the periodontal status of type 2 diabetes Mellitus (DM) patients and the relationship between periodontal conditions and diabetic complications. The subjects were 105 patients (mean age, 55.4±11.3) with type 2 DM taking part in an education program at Keio University Hospital. The periodontal assessment included the number of teeth present, probing pocket depth (PPD), bleeding on probing (BOP) and tooth mobility. A questionnaire was used to elicit the subjectsʼ gender, age, body mass index (BMI), DM duration, blood pressure, and systemic diseases.The presence of DM-related complications namely nephropathy, retinopathy (SDR：PPDR：PDR), arteriosclerotic disease, and neuropathy were evaluated by a doctor of internal medicine. The number of teeth remaining

Abstract：The aim of this study was to examine the effect of sitafloxacin (STFX) on an in vitro dental biofilm model. Eradication of periodontal bacteria within the biofilm and formation of a biofilm itself is an important issue in the treatment of periodontal diseases. Periodontal biofilms are often recognized as being composed of polymicrobial aggregates, that are resistant to various antimicrobial agents and disinfectants to which planktonic bacteria are susceptible. STFX is an oral new quinolone antibacterial drug that has a broad antibacterial spectrum, including oral anaerobic bacteria. STFX has been approved for the treatment of respiratory tract and urinary tract infections, as well as for that of odontogenic infections in Japan. In this study, we used a novel microfluidic device, BioFlux, which was designed to run an automated culture flow under the anaerobic condition and is expected to be useful for in vitro oral biofilm experiments. A mixture of Porphyromonas gingivalis ATCC33277 and Streptococcus gordonii ATCC35105 was introduced into the microfluidic channels and then allowed to attach and form a biofilm for a total of two hours at 37℃. The formation of the biofilm on the surface of the channels was observed by microscopy. STFX or azithromycin (AZM) solution was then added to the BioFlux 406

Abstract： The aim of this study was to evaluate the plaque removal efficacy of three tooth brushes：the Philips Sonicare Diamond Clean with a medium brush head, Philips Sonicare Diamond Clean with a mini brush head, and the Philips Sonicare Flexcare with a medium brush head. This study was an investigator-blinded, three-brush crossover design study. Twenty dentists with clinically healthy gingiva and without restorative materials or prosthetic teeth participated in this study. Prior to the experiment, the subjects received a professional prophylactic program and were requested to refrain from brushing their teeth for 48 hours. Assessment was carried out using the modified OʼLearyʼs plaque control record (6 sites per tooth) at the baseline and after each brushing interval by one blinded investigator. The PCR score was 100% at the baseline in all subjects. The results showed no statistically significant differences in the PCR score among the three tooth 140

：The purpose of this study was to clarify the usefulness of serum antibody titers for periodontopathic bacteria as a screening test for periodontal disease in diabetic patients. The subjects comprised 28 diabetic patients who were hospitalized in the Department of Internal Medicine of Keio University Hospital for various periods between July 2010 and December 2011 (mean age, 56.6±10.7 years；18 men, 10 women；mean illness duration, 8.7±6.3 years). Periodontal parameters, including probing pocket depth, bleeding on probing, and tooth mobility, were recorded, and blood tests including hemoglobin A1c, blood glucose level, C-peptide, hs-CRP and the serum antibody titers for four peridontopathic bacteria (Aggregatibacter-actinomycetemcomitans, Eikenella corrodens, Prevotella intermedia, and Porphyromonas-gingivalis) were examined at the time of the first visit to