The Journal of Nihon University School of Dentistry最新文献

This report reviews the clinicopathologic characteristics of 104 cases of odontomas diagnosed in the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, over a 29-year period (1967-1995). The results showed no real predilection in terms of sex (M:F ratio, 1:1), race (45.2% Malays, 40.4% Chinese, 10.6% Indians and 3.8% other races) or site (maxilla:mandible ratio, 1: 1.04) distribution. The mean age at presentation was 24.8 years and the age range was 3-74 years. There were 102 intraosseous and 2 extraosseous odontomas. Swelling was the most common presenting complaint. The majority of cases (81.9%) were clinically diagnosed as odontomas. The treatment of choice was surgical enucleation. Compound (43.3%) and complex (35.5%) odontomas were the two most common histological types encountered. The present findings correlate favorably with reported studies from other geographic areas.

Rabbit polyclonal antibody against mouse EHS laminin was used to investigate the distribution and composition of laminin in the rat first molar tooth germ. Immunohistochemical analysis showed that laminin is expressed in the inner and outer epithelia of the enamel organ and in small blood vessels in the dental papilla and strellate reticulum. Immunoblots revealed that tooth germ laminin differs from EHS laminin. Tooth germ laminin contains beta chains, while the alpha 1 chain is substituted by a 300-kDa chain. Two-dimensional electrophoresis analysis of tooth germ extract showed that beta chains appeared as four spots with approximate pI values of 6.6, 7.5, 7.8 and 8.5. These results indicate that more than-one type of laminin isoform is present in the first molar tooth germ. Additionally, we have shown that despite the early degradation of tooth germ basement membrane, the laminin molecule is still intact at the time of birth.

The purpose of this study was to provide information about arch shape variations among South Pacific populations. The application of Fourier transforms, Y(phi i) = ao/2 + sigma (aicos phi i + bisin phi i) was used to separate two components of variation; size and shape. Dental arch size can be described by one coefficient (ao), while the shape can be summarized by the first three harmonics (amp1-3) in the Fourier series. The materials used in this study were dental casts of South Pacific populations (Fiji, Western Samoa and Kiribati), Australian Aboriginals and Japanese. Fijians, Western Samoans and Kiribati people have larger upper and lower dental arches than that of Japanese. These populations were separated by the arch size and first Fourier amplitudes which showed the arch depth/width ratio. The Fijian upper and lower dental arches were significantly larger than those found in other populations and was characterized by a wide posterior arch breadth. The Western Samoan and Kiribati arch shape was more similar to the Japanese arch shape than the Fijian. Distribution patterns of arch shape characteristics in these populations showed the same tendencies in the upper and lower arches.

A useful gelatinolytic enzyme assay for fibroblasts, utilizing a novel sample preparation method for collagenase with dithiothreitol (DTT) treatment to inactivate endogenous collagenase inhibitors, was developed using soluble fluorescein isothiocyanate (FITC)-labeled gelatin. The substrate, gelatin was prepared by heating commercially available FITC-labeled type I collagen. The denatured collagen was cleaved with purified trypsin and partially purified fibroblast gelatinase, and the digested FITC-fragments were measured fluorometrically. The intensity of the fluorescence was in proportion to the reaction time and enzyme concentration. Both enzyme activities were measurable within the nanogram range of enzyme preparations. The enzyme activity was detected after 4-aminophenylmercuric acetate (APMA) treatment which was completely inhibited by metalloproteinase inhibitors, but not by serine- and cysteine-proteinases' inhibitors. Conditioned media of human periodontal ligament fibroblasts (PLF) and gingival fibroblasts (GF) were separately treated with DTT prior to the enzyme assay, and then the assay was performed in the presence of APMA. The enzyme activities of PLF and GF were 106- and 55-fold higher than those of the conventional gelatinase assay which was carried out without DTT treatment. This assay method allowed the measurement of gelatinolytic enzyme activity when tissue inhibitors of metalloproteinases were present in the fibroblast culture medium.

The effects of unilateral extraction of the upper incisor (one tooth) on facial growth of young rats were studied. The remaining upper incisor showed deviation towards the opposite side, and there was regular dental wear of all the incisors. The effects were evident only in the mid-facial area. Cephalometric measurements showed significant shortening with deviation of the incisor bone on the extraction side. There was no significant disturbance of the growth of the rest of the maxilla and mandible. These results indicate that upper incisor extractions have a localized influence, leading to impairment of incisor bone growth.

We report a 46-year-old woman who presented with a hemangiopericytoma in the buccal mucosa. At the 2-year postoperative examination, there was no evidence of recurrence or metastasis. The findings in the present case are compared with previous reports in the Japanese literature, with regard to patient age and sex, and lesion size, location, malignancy, local recurrence and metastasis.

In recent years, the use of mouthwash has become widespread as a part of routine oral hygiene. However, there have been no fundamental studies on the influence of mouthwashes on the human oral mucosae. One hundred and twenty-five subjects (50 males and 75 females) were selected for this study. The effects of mouthwash was assessed with the use of exfoliative cytological and cytomorphometric analyses of smears obtained from clinically normal upper labium and cheek mucosae before mouthwashing, 30 s, 10 min and 1 h after mouthwashing. The independent variables examined were oral site, sex and smoking (smokers versus never-smokers). In all subjects and sites, the appearance rate of exfoliated cells stained by light green SFY decreased just after mouthwashing, and the rate after 1 h was lower than that of the untreated controls. The oral mucosae of smokers were more irritated action by mouthwashing than that of the never-smokers. Even after 1 h, decreases in the nuclear and cytoplasmic areas of cells and increases in inflammatory cells were observed. In conclusion, the use of mouthwash was so inflamed the human oral mucosae that more attention should be paid when it is used daily in oral hygiene.

A study was conducted to comparatively evaluate the efficiency of different solvents for dissolving gutta-percha. Halothane, chloroform, xylene, acetone, isopropyl alcohol, turpentine, oil of mela-leuca and eucalyptol were used as solvents for dissolving standardized gutta-percha discs. Halothane, chloroform and xylene were markedly superior solvents of gutta-percha in comparison with the others. There was no significant difference among the three (p > 0.05). Eucalyptol, turpentine and oil of melaleuca were relatively less efficient. Acetone and isopropyl alcohol did not dissolve gutta-percha, being similar in this respect to distilled water.

Fluoride release from six light-activated restorative materials, including two resinmodified glass-ionomers, two composites, and two compomers, was evaluated and compared with one conventional acid-based glass-ionomer cement. The amount and rate of release varied among the tested materials. Both resin-modified glass-ionomers and the conventional acid-base glass-ionomer cements released more fluoride then the composites and compomers (p < 0.05). Additionally, composite materials released less fluoride than compomer materials (p < 0.05). Release of fluoride by the tested materials showed a significant decrease after all the tested time intervals.

In this study, the focus was on the antibacterial activity of onions. This study researched the activities of onion extracts on Streptococcus mutans and Streptococcus sobrinus, the main causal bacteria for dental caries, and Porphyromonas gingivalis and Prevotella intermedia, considered to be the main causal bacteria of adult periodontitis. The results showed that the onion extracts possess an effect on all test bacterial strains (S.mutans JC-2, S. sobrinus OMZ176, P. gingivalis ATCC 33277 and P. intermedia ATCC 25611), and the effects were bactericidal against cultured and resting bacterial cells. The activity of the onion extracts was stable even after 48 hours in the culture medium. This result suggests that no decomposition or volatility of onion extracts occurred in the culture medium. The antibacterial activity of onion extracts was not markedly influenced by cysteine (10 mM) treatment. However, activity significantly decreased with alkali treatment. Grated onion left to stand at 37 degrees C for 48 hours did not show antibacterial activity. Also, activity of steam treated (100 degrees C, 10 min.) onion was not observed. Using avicel plate by thin layer chromatography with the solvent of n-butanol:acetic acid:water (3:3:1), the main component of the substance (the substance which develops color with ninhydrin) was observed at an Rf value of about 0.9.