We examined the effect of Emdogain^® Gel (EMD) on the regeneration of periodontal tissue and demonstrated immunohistochemical changes of nerve fiber and mechanoreceptors in the repairing of periodontal ligament (PDL) of a rat replantation model. Maxillary right incisor of male Wistar rats was extracted. After removing pulp tissue from root apex side, the intracanal was filled with warmed gutta-percha by retrograde root canal filling. In the experimental group (EMD group) was used EMD at 0.05ml to root surface before replantation. Untreated group (UT group) was replanted immediately. The samples were extracted on day 3 and at 1, 2 and 4 weeks after surgery. The samples were stained with hematoxylin and eosin (H.E), immunostained with protein gene product 9.5 (PGP 9.5) and Na⁺, K⁺ -ATPase β1fusion protein (Na⁺, K⁺ -ATPase). In EMD group was recognized continuing recovery of PDL more quickly than UT group at 1 week. In the EMD group, islet-shaped bones were hypertrophied in the PDL at 1 week. And Na⁺, K⁺ -ATPase positive reaction which demonstrated recovery of the mechanoreceptors activation was recognized to the Ruffini endings at 1 week. In EMD group was recognized more hypertrophy of alveolar bone at the periradicular than UT group at 2 weeks. In both groups, the constriction of PDL space and the sectional root absorption were recognized at 4 weeks. In conclusion, the continuity of the PDL fiber and the activity of the ruffini endings showed early recovery by applying EMD to the tooth replantation of rat. Bone development was started early even with the PDL and the periradicular alveolar bone. However, the application of EMD couldn't prevent the constriction of PDL space and the root absorption.

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Rheumatoid arthritis (RA) is an inflammatory joint disorder, the progression of which leads to the destruction of cartilage and bone. Low-level laser irradiation (LLLI) is currently being evaluated for the treatment of RA, but the molecular mechanism underlying the effectiveness of LLLI in RA is unclear. B-cell-attracting chemokine-1 (CXCL13) is classified as a lymphoid chemokine and is a potent B-cell chemoattractant, leading to the local production of the autoantibody. The objective of this study was to determine whether LLLI decreased CXCL13 gene expression in joints of collagen-induced RA (CIA) rats. CIA caused swelling of rat joints, and LLLI significantly decreased the swelling. Total RNA was isolated from synovial membrane tissue of CIA rat joints with or without treatment from an 830 nm Ga-Al-As diode LLLI, and gene expression profiles were analyzed by DNA microarray (rat 41,000 genes). DNA microarray analysis showed that CXCL13 gene expression was increased in CIA tissue, and that LLLI significantly decreased the CIA-induced CXCL13 mRNA level. The reduction in CXCL13 gene expression was confirmed by reverse transcription polymerase chain reaction (RT-PCR) and real-time PCR. The findings suggest that decreased CXCL13 gene expression may be one of mechanisms involved in the reduction of inflammation in RA by LLLI.

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Cytotoxicity is one of the most important problems in medical metal materials. Effect of different dental alloys on cytotoxic of L929 cells was evaluated by in vitro cytotoxicity-test (MTT method). Metal ion concentration was one of the factors leading to occurrence of cell toxicity. Thus metal ion concentration in cell culture fluid at different intervals of immersion periods were detected by inductively coupled plasma mass spectrometry (ICP-MS). For different medical metals, RT-PCR method was also used to analysis mRNA expression of L929 cells' caspase-3, caspase-8 and caspase-9. The results indicated that MTT test found little optical density (OD) value difference for different alloys at different time points. The cytotoxicity of Cu alloy group was Grade 4 and those of other groups were all Grade 0 after 48 hours culture. The mRNA levels of caspase-8 had no change in all groups. The mRNA levels of caspase-3 and caspase-9 were as follows from low to high: Cu alloy, the negative control and Au alloy, Co-Cr alloy, Ag-Pd alloy,and Ni-Cr alloy after 48 hours' culture. It is concluded that metal ions of the studied dental alloys may induce cell apoptosis by different degree through mitochondrion pathway. Apoptosis related genes expression of L929 cells was affected by ion concentration in cell culture fluid.

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The purpose of this study was to investigate changes in bone quality associated with the mineralization of new bone forming around implants. Eight 18-week-old male New Zealand white rabbits and implants fabricated from Ti-15%Zr-4%Nb-4%Ta alloy were used in the study. Characteristics of new bone formed around implants at 4 and 8 weeks and cortical bone were compared using X-ray photoelectron spectroscopy (XPS) for elemental qualitative and quantitative analysis, polarized microscopy (PM) for histological examination, and Fourier transform infrared Imaging (FTIR Imaging) to characterize molecular distributions in new bone and cortical bone. Results from XPS analysis showed changes in the chemical bonding in new bone over time (4 weeks vs. 8 weeks). PM showed changes in collagen birefringence, orientation and intensity in new bone over time, becoming more similar to those of cortical bone after 8 weeks. FTIR Imaging showed that in new bone close to cortical bone, amounts of PO₄^3- and CO₃^2- ions (representing mineral or inorganic components), and amounts of amide I (representing the organic component) increased over time as mineralization progressed. In new bone more distant from cortical bone, PO₄^3-, CO₃^2-, and amide I distributions also increased over time, but to a lesser extent to that observed near cortical bone. Our findings clearly showed changes in the quality of new bone forming around implants, and these changes were related to mineralization.

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To quantify biomarkers of inflammation and tissue destruction in gingivo crevicular fluid to contribute to the diagnosis of the severity of the gingivo—periodontal disease. 115 adults with gingival-periodontal disease were included. Diagnosis was determined through clinical and radiographic criteria. Samples were obtained from six to eight sites per patient. Data were analyzed by an SPSS system using ANOVA One Way and Tukey tests. Volume raised in gingivitis, moderate and severe periodontitis Total proteins and hydroxyproline increased in moderate and severe periodontitis. Electrophoresis evidenced protein bands that increased with the severity of periodontitis. Some were similar to serum proteins and an additional band of less than 14 kDa was present in all the periodontitis samples. Collagenase bands evidenced differences between healthy and diseased subjects. Calcium determinations showed no statistically significant differences among groups. Levels of gingivo crevicular fluid biomarkers specific for inflammation and collagen degradation correlate with the clinical diagnosis in patients with gingivitis and chronic periodontitis.

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Background: Patient-controlled epidural analgesia (PCEA) techniques and intrathecal morphine (ITM) are the most widely used treatments for post-Caesarean section pain. We investigated of these two methods on the duration of postoperative 48 h with respect to analgesic quality. Methods: Fourty patients scheduled for elective Caesarean section were randomized to receive for postoperative analgesia either PCEA with containing meperidine or intrathecal morphine 0.2 mg together with the spinal anaesthetic and diclofenac was added as necessary. Postoperative analgesic requirements, quality of analgesia, patients satisfactions, and side effects were evalueted. Results: The addition of diclofenac to the lowest dose of intrathecal morphine appeared to provide nearly equal postoperative analgesia to the PCEA with meperidine during the 48 h study period, because of nausea and vomiting occurred more than patients were slightly lower in patients satisfaction than CSE group. Conclusions: It was concluded that PCEA induced better pain relief, caused less nausea/vomiting than intrathecal morphine.

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In cancers of the oral cavity, high histological malignancy grade is associated with higher risk of cervical lymph nodes, lung and bone metastases, which have great impact on the prognosis. Furthermore, early detection of these cancers is desirable so that treatment can aim at conserving oral functions and improving prognosis. It is known that several percent of leukoplakia that develop in the tongue become cancerous. Leukoplakia is a clinical diagnostic term, and histopathologically most cases show hyperkeratosis with epithelial dysplasia or hyperkeratosis without epithelial dysplasia. On the other hand, difficulties in histopathological diagnosis of severe epithelial dysplasia and carcinoma in situ are often encountered. In recent years, immunohistochemical staining of cytokeratins (CK), p53 and Ki-67 for precancerous lesions and squamous cell carcinoma (SCC) of the oral cavity has been reported. However, few reports have applied a combination of several immunohistochemical stainings to diagnosis. In the present study, with the objective to achieve a higher precision in histopathological diagnosis, we conducted and compared the immunohistochemical stainings of CK13, CK17, CK14 and p53 in 10 cases each of hyperkeratosis without epithelial dysplasia, hyperkeratosis with epithelial dysplasia, carcinoma in situ, and SCC in the tongue. The following results were obtained. CK13 was positive in all 10 cases of hyperkeratosis without epithelial dysplasia, and negative in all cases of hyperkeratosis with epithelial dysplasia, carcinoma in situ, and SCC. CK17 was negative in all 10 cases of hyperkeratosis without epithelial dysplasia, and was positive in all 10 cases of hyperkeratosis with epithelial dysplasia as well as 10 cases of carcinoma in situ and 9 of 10 cases of SCC. CK14 was negative or positive only in the basal cell layer or a few rows of cells in spinous layer adjacent to the basal cell layer in cases of hyperkeratosis without epithelial dysplasia, but was positive in all the epithelial layers in all 10 cases of hyperkeratosis with epithelial dysplasia, and also positive in the tumor in all 10 cases each of carcinoma in situ and SCC. For p53, positive reaction was observed in some cells of the basal cell layer in 2 of 10 cases of hyperkeratosis without epithelial dysplasia, while high positive rates were found in hyperkeratosis with epithelial dysplasia (10 of 10 cases) and SCC (9 of 10 cases). On the other hand, only 5 of 10 cases of carcinoma in situ were positive for p53. In conclusion, although the histopathological diagnosis of epithelial dysplasia and carcinoma in situ is based on hematoxylin-eosin stained sections, immunostaining and evaluation of CK13, CK17, CK14 and p53 are useful as an adjunct to histopathological diagnosis.

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Wavelength-tunable monochromatic Parametric x-ray (PXR) was generated at the Laboratory for Electron Beam Research and Application (LEBRA) at Nihon University. Using the LEBRA-PXR, phase contrast imaging was carried out. Phase contrast images of a kitten deciduous tooth were taken by diffraction enhanced imaging (DEI) method. The results showed that LEBRA-PXR is a high coherent x-ray and is suitable for phase contrast imaging.

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