The aim of this study was to investigate whether the missing teeth in dental professionals thought that information in the mouth was obtained easily and consideration to the health care of the mouth high exerts the factors. The subjects of this study were 271 dental personnel (68 male and 203 female) in Nagasaki National Health Insurance Organizations.
Using the number of missing teeth were as the response variable, a multiple regression analysis was conducted using parameters in the mouth, systemic parameters, and psychological parameters as covariates.
In the multiple regression analysis of which the response variable was the missing teeth, the influence was intentionally exerted on the results of the analysis revealed significant influence of the ALP, Hb, age, average of blood pressure, smoking habit, stress, systemic disease, repose time and working hours on the number of missing teeth in the study subjects.
Thus, the number of missing teeth was influenced by the environment in the mouth, systemic condition, and stress. It was suggested that examination of the mouth for periodontitis, might provide important clues to the state of the mouth, systemic condition and lifestyle factors of a patient.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 52(4) : 381-390,2010.

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Transforming growth factor-beta 1 (TGF-β1) and 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) are both known to influence cell growth and differentiation. However, little is known about the effects of TGF-β1 and 1,25(OH)₂D₃ on human periodontal ligament cells. This study was performed to examine the effects of TGF-β1 and 1,25(OH)₂D₃ on the alkaline phosphatase (ALP) activity, cell growth and expression levels of marker genes in the periodontal ligament cells.
Methods: HPdLF and HPDL were used as the human periodontal ligament cells, NHOst as human bone cells and HDPC as human dental pulp cells. The ALP activity of the HPdLF cells treated with TGF-β1 (0.1-10ng/ml) and 1,25(OH)₂D₃ (1-200nM) were first measured and then with that of the other treated cells. HPdLF cells were also used for the subsequent experiments. The ALP expressions were determined by the ALP activity and ALP staining. Cell growth was measured by the MTS assay. The expression levels of the osteocalcin (OC) and periodontal ligament associated protein-1 (PLAP-1)/asporin genes were measured by RT-PCR and quantitative real-time RT-PCR.
Results: Both TGF-β1 and 1,25(OH)₂D₃ showed synergistic effects on the ALP activity, in both the HPdLF and HPDL cells, while no such synergistic effect was observed in the NHOst or HDPC cells. HPdLF cells were therefore used for the subsequent more specific experiments. TGF-β1 and 1,25(OH)₂D₃ induced stimulation of the ALP activity in these cells, whereas they inhibited the proliferative activity of the HPdLF cells in a time-dependent manner. Examination by staining for ALP expression revealed a marked increase in the number of ALP-positive cells in the HPdLF cells following treatment with TGF-β1 and 1,25(OH)₂D₃. At the gene expression level, TGF-β1 and 1,25(OH)₂D₃ significantly induced the expression of the OC gene, however, they downregulated the expression of the the gene for PLAP-1/asporin synthesis.
Conclusion: TGF-β1 and 1,25(OH)₂D₃ exerted significant effects on normal human periodontal ligament cells under certain conditions, and the cellular responses differed depending on whether the cells were osteoblasts or pulp cells. These findings suggest that TGF-β1 and 1,25(OH)₂D₃ exert remarkable effects on the periodontal ligament cells, and that they specifically promote the differentiation of these cells into osteogenic cells.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 52(4) : 391-400,2010.

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The purpose of this study was to examine the salivary LL-37 levels together with the presence/absence of major periodontopathic bacteria, and to evaluate the clinical relevance of this antibacterial peptide in patients of periodontitis. Unstimulated salivary samples were collected from 72 periodontitis patients and 22 periodontally healthy controls. The concentration of LL-37 in the saliva was measured by enzyme-linked immunosorbent assay, and the presence of four periodontopathic bacteria (P. gingivalis, T. forsythia, T. denticola, A. actinomycetemcomitans) was determined using polymerase chain reaction. Periodontal examination included determination of the probing pocket depth (PPD), the clinical attachment level (CAL), and bleeding on probing (BOP). The subjects with periodontitis showed significantly higher LL-37 levels in the saliva than the healthy controls. A higher prevalence of periodotopathic bacteria was observed in the periodontitis patients, and the salivary LL-37 levels were particularly elevated in patients with T. denticola or A. actinomycetemcomitans as compared to the results in patients without these periodontopathic bacteria. The salivary concentration of LL-37 was positively correlated with the percentage of teeth with a PPD of ≥ 5mm or CAL of ≥ 5mm in the periodontitis patients. The results of multiple regression analysis revealed that the concentration of LL-37 in the saliva was significantly correlated with the presence of T. denticola. In conclusion, production of LL-37 seemed to be increased in association with periodontopathic bacterial infection. However, it was not sufficient to eliminate these bacteria and prevent periodontal destruction in patients with periodontitis.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 52(4): 401-408,2010.

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This study was aimed at examining whether periodontal therapy might affect the interproximal contact (CT) and occlusal force (OF). Twenty patients (15 males and 5 females) diagnosed to have chronic periodontitis were enrolled in this study after obtaining informed consent. All patients received periodontal initial treatment. The CT was evaluated with a contact gauge (S. D. contact gauge^®, San Dental Co., Japan). Sites with CT ≤ 50 μm at the first examination were excluded, and 206 interdental sites were selected for the analysis. OF was examined with a Dental Prescale^®(GC Co., Japan) and calculated for each interdental site. Statistical analysis was performed to determine the relationship between the change of the CT and that of the OF. These parameters were also compared at each interdental site (anterior, premolar and molar teeth).
The results obtained were as follows: 1) The CT decreased significantly after the periodontal initial treatment; 2) the OF increased significantly after the periodontal initial treatment; 3) a significant correlation was observed between the change of the CT and change of the OF, 4) a significant correlation between the change of the CT and change of the OF was observed only for the molar sites.
The results indicate that reduction of inflammation at the interproximal sites leads to a tight CT following periodontal initial treatment, and that the occlusal force (OF) can be affected by increase in the tightness of the interproximal contact (CT).
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 52(4) : 409-418,2010.

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Sufficient knowledge and clinical ability is required for undergraduate students to perform proper periodontal treatment after graduation. On the other hand, it is argued that dental students do not possess sufficient skills in clinical techniques or a proper understanding of the treatment processes. To help students understand the whole spectrum of periodontal treatment, a student-attended clinical training program is considered to be useful.
We assigned a 60-year-old female patient to a 5^th grade dental student. Relatively great care was necessary for the patient, because her physical condition was not too good because of anticancer treatment, and she also had a fear of dental treatment. However, careful explanation and treatment prevented big problems. The patient had several oral problems, including gingival inflammation, vertical bone loss in the molar area, and occlusal problems. The student was assigned the responsibility for examination, diagnosis, treatment-planning, basic periodontal treatment, periodontal surgery and oral function recovery, and we are now carrying out supportive periodontal therapy (SPT) in this patient.
We also received a feedback from the patient about the student's treatment performance. Explanation and effort to relieve the patient's tension by the student was found to be insufficient, but the care provided for pain and the student's basic manners were highly appreciated. The patient expressed satisfaction with the overall dental treatment.
The student-attended clinical training program of the time was considered to be effective for the student to understand the whole process of periodontal treatment. It is considered that this report of the results of student-attended clinical training will have a high educational effect, such as raising students' motivation for periodontal treatment.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 52(4) : 419-428, 2010.

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