Calcium phosphates have been used safely and effectively as bioceramics for designing alveolar bone grafts. Calcium phosphate bioceramics, hydroxyapatite (HA), β-tricalcium phosphate (β-TCP), and a mixture of these calcium phosphates are extensively used as bone substitutes. When these materials are placed in alveolar bone defects, they promote new bone formation. Bioceramics that show osteoconduction have the ability to induce new bone formation, and are employed as bone substitutes and scaffolds in bone tissue engineering. Moreover,these materials as scaffolds are used with growth factors and matrix proteins, and these complexes enhance bone formation. The combination of growth factors and calcium phosphates appears to have excellent capacity to induce regeneration.

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We hypothesized that analysis of mouth air would be indicative of not only periodontal status but also populations of periodontal pathogens in periodontal pockets. Oral malodour and volatile sulphur compounds (VSCs) concentrations in mouth air from 30 subjects were examined by electronic nose, gas chromatography and organoleptic tests. Several periodontal parameters were also recorded. Periodontal pathogens, i.e. P. gingivalis, A. actinomycetemcomitans, T. forsythia, P. intermedia and T. denticola were analyzed in saliva, tongue coating and subgingival plaque by real-time PCR. The following results were obtained. 1.The max probing pocket depth (PD) was significantly correlated with oral malodour expressed as organoleptic score, total mode of electronic nose and CH₃SH/H₂S ratio. 2.Total measurement mode of electronic nose, CH₃SH/H₂S ratios significantly correlated with total level of the microorganisms in subgingival plaque(adjusted R² =0.690，p＜0.027). A significant positive correlation was demonstrated between the actual measurement value and the forecast value of the total level of the five periodontopathic microorganisms in subgingival plaque (R²＝0.447, p＜0.001). Electronic nose measurements or CH₃SH/H₂S ratio would be a practical indicator of periodontal health status. Mouth-air analysis might indicate the level of periodontopathic microorganisms in periodontal pockets. Nihon Shishubyo Gakkai Kaishi (JJpn Soc Periodontol) 56(4)：379-389, 2014.

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Aspartate aminotransferase (AST) is an enzyme used clinically as an indicator of cell injury in pathological conditions in which cytoplasmic enzymes are liberated into the extracellular fluid, increasing the AST concentrations in the serum. Elevated gingival crevicular fluid (GCF) levels of AST serve as a useful indicator of the disease activity of periodontitis. In this study, we measured the AST levels in GCF from chronic periodontitis patients before and after initial therapy or periodontal surgery (periodontal regeneration therapy using Emdogain^® gel) using a Periodontal Tissue Monitor (PTM) kit, and investigated the relationships among the AST levels (PTM values) and the probing pocket depth (PPD), clinical attachment level (CAL) and bleeding on probing (BOP). After the initial therapy, the PTM values improved at 22 out of 38 treatment sites. Among the 22 sites, PPD at 20 sites, CAL at 15 sites, and BOP at 21 sites either improved or showed no change. After periodontal surgery, the PTM values improved at 42 out of 56 treatment sites. Among the 42 sites, PPD at 39 sites, CAL at 32 sites improved, and BOP at 41 sites either improved or showed no change. Next, we explored the relationship between the PTM values and the mean PPD and CAL after periodontal surgery. In the 42 sites that showed improved PTM values, the mean PPD and CAL were significantly decreased. However, in the 14 sites that showed no change or deterioration of the PTM values, only the mean PPD was significantly decreased. The results suggest that sites with improved PTM values after periodontal surgery might not only show shallow PPDs, but also CAL gain. When we compared the amount of CAL gain and PTM values after periodontal surgery, the sites showing greater CAL gain tended to show lower PTM values. These studies suggest that measurement of the AST levels in GCF is useful for predicting the prognosis of periodontal disease. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：390-398, 2014.

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The purpose of the present study was to evaluate the bactericidal effects of generating active oxygen species (O*) and ultraviolet (UV) wavelengths in a sterilization system utilizing ultraviolet irradiation. After planting Escherichia coli (E. coli) or Candida albicans (C. albicans) on rubber cups that are often used for professional mechanical tooth cleaning, sterilization using O*, UV, or O*+UV was performed for 5 or 25 min. We evaluated the residual numbers of E. coli or C. albicans on the sterilized rubber cups using the 10-times dilution method or the adenosine triphosphate (ATP) method. The bactericidal effects of O*, UV, and O*+UV were then compared with the results in a control group (no O* or UV). The results showed that among all 4 methods, O*+UV had the most powerful bactericidal effects on E. coli and C. albicans, followed by UV and then O*. Moreover, when the bactericidal effects of O*+UV were compared with those of UV, the addition of O* was significant. These findings indicated that the bactericidal effects of generating O* and UV in a sterilization system using ultraviolet irradiation could be useful for the sterilization of dental materials that are heat-labile and that would be destroyed by autoclaving. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：399-405, 2014.

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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 system and the continuous flow was resumed for five days under the anaerobic condition. We chose the following drug concentrations：0.65 and 1.30 μg/ml for STFX, and 2.92, 3.95 and 7.90 μg/ml for AZM, calculated based on the concentrations reached in the gingiva and gingival crevicular fluid when STFX and AZM are administered orally in adult patients. After continuous exposure of each drug to the already established biofilm, the rate of viable cells present in the biofilm was quantified by fluorescence microscopy and an image analysis technique using the LIVE/DEAD^® BacLight^TM Kit. We found that each of the drugs decreased the viable cell rate of the co-culture of P. gingvalis and S. gordonii in a dose-dependent manner. Notably, STFX significantly decreased the number of viable cells in the biofilm as compared to AZM (p＜0.05). These results suggest that STFX has the potential to inhibit oral biofilm formation and/or exert bactericidal activity against even those periodontal pathogens that are present in biofilms. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：406-413, 2014

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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 our department. A periodontal examination and blood tests were also performed one month after the initial periodontal therapy. Based on the serum antibody titers for P. gingivalis at the first visit, the subjects were divided into a high antibody titer group (antibody titer for P. gingivalis, 1.0 ELISA unit or more) and a low antibody titer group (less than 1.0 ELISA unit). The mean probing pocket depth was significantly deeper in the high antibody titer group than in the low antibody titer group. In addition, a statistically significant relationship was shown between the probing pocket depth and the serum antibody titer against P. gingivalis at the first visit. The serum antibody titers after the initial therapy tended to decrease, compared with the results obtained at the first visit, but the differences were not statistically significant. These results suggest that serum antibody titers for P. gingivalis are useful for the screening of periodontal disease in diabetic patients, and also suggest that the limit of the titers for P. gingivalis may be around 1.0 ELISA unit. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：414-422, 2014.

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The purpose of this study was to examine the relationship between the progression of arteriosclerosis, which causes coronary heart disease (CHD), and the state of periodontal disease in hypertensive patients. The progression of arteriosclerosis was evaluated by measuring the pulse wave velocity (PWV) using an automatic waveform analyzer. A total of 71 patients with hypertension (age 61.1±9.6 years) were enrolled in this study. As the clinical parameters of periodontal disease, we examined the probing pocket depth (PD) and bleeding on probing (BOP) for six teeth, at six sites per tooth, and examined the bacterial flora in the subgingival plaques of four teeth by culture. The subjects were divided into two groups according to the median PD and BOP; the high group (PD≧3.8 mm,BOP≧40%) and the low group (PD＜3.8 mm, BOP＜40%), and the data were statistically analyzed. The results were as follows: The mean value of the PD measured at 36 sites was 4.0±1.0 mm, the mean of the deepest PD among the six sites in each tooth was 6.2±2.2 mm, and the percent BOP was 43.6±29.4%. These results suggest a considerable degree of progression of periodontitis in the subjects. The PWV was significantly (p ＜0.05) higher in the high-BOP group than in the low-BOP group. The detection frequency of Prevotella spp. was significantly higher (p＜0.05) in the high-PD group than in the low-PD group, and also significantly (p＜0.05) higher in the high-BOP group than in the low-BOP group. These results suggest that hypertensive patients with a high BOP are at a considerably elevated risk for CHD. Furthermore, it appeared likely that Prevotella spp. may be involved in the progression of periodontal disease in hypertensive patients. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：423-434, 2014.

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Tooth displacement occurring at a high prevalence in patients with severe periodontitis is defined as pathologic tooth migration (PTM). For these patients, the malposition of the teeth not only creates unfavorable conditions for maintaining good oral hygiene, but also causes occlusal discrepancy and further traumatic occlusion. Consequently, it easily promotes progression/recurrence of periodontal disease. Herein, we present the case of a 49-year-old woman with generalized severe chronic periodontitis exhibiting several PTMs with categorized into skeletal Class Ш. The patient received comprehensive treatment, including periodontal initial therapy, periodontal surgery (bone grafting), localized orthodontic treatment utilizing a removable bite plate and orthodontic anchor screws, and restorative/prosthodontic treatment. Through this interdisciplinary approach, a favorable periodontal condition, consecutive dentition, and proper anterior guidance were efficiently restored in a relatively atraumatic manner. The periodontal health and stable occlusion were well maintained until at least 3 years later in the patient on supportive periodontal therapy. The findings in this case suggest that an interdisciplinary approach,including orthodontic treatment, for controlling both inflammation and occlusal force is essential for achieving successful results of periodontal treatment in patients with severe periodontitis and PTM. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：442-450, 2014.

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Pemphigus vulgaris is an autoimmune disease that forms intraepithelial blisters on the skin and mucous membranes, including the oral mucosa and gingiva. In this paper, we report a case in which nonsurgical periodontal therapy was successfully applied for the treatment of periodontitis with pemphigus vulgaris exhibiting severe edematous swelling and desquamative erosion. A 56-year-old woman visited our hospital because of gingival swelling and bleeding during brushing. She suffered from pemphigus vulgaris and had routinely visited a dermatologist since her 30s, but had not routinely visited a dentist. At her initial visit,edematous swelling and desquamative erosion were observed in the oral mucosa and gingiva. A probing pocket depth of over 4 mm was observed at 79.7% of the sites, and large quantities of plaque and calculus were deposited on the teeth because of insufficient brushing as a result of pain. Moderate bone resorption was confirmed using an X-ray photograph. First, we provided oral hygiene instructions with careful attention to her oral symptoms. Since her periodontal condition improved in parallel with her self-improvement in plaque control, we performed scaling/root planning and treatment for the recovery of occlusal function. At present, edematous swelling and desquamative erosion are not observed, and her oral condition has been well maintained. The presence of plaque is considered to be a key modulator aggravating the oral symptoms of pemphigus vulgaris, and careful oral hygiene instruction tailored to a patientʼs clinical symptoms is important for periodontal treatment in patients with pemphigus vulgaris. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：451-456, 2014.

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