Panoramic radiographs often show a dome-type uniform shadow in the maxillary antrum that is a retention cyst occurring in the mucosa. I investigated the clinical, biochemical and histological aspects of this lesion. I screened 1397 subjects and found shadows that seemed to be hydroceles in the maxillary antrums of 89 them(6.4%). Eight of the cases were bilateral. Since 47 of the cases were males and 42 females, there did not seem to be significant gender difference. Thirty of hydroceles were on the left side, 51 on the right, and 8 were bilateral. Sixty-four(66%)of the hydroceles were asymptomacic. The patient complained of buccal region discomfort for 31(32%)of the hydroceles, heavy-headedness for 8(8%)and tooth discomfort for 4(4%). Neither dental infections nor nasal allergies seemed to contribute to development of this cyst. Endscopic examinations of 65 cysts revealed that 48(74%)showed a large second aditus at meatus nasi medius and that 31(48%)of the hydroceles could be observed in maxillary antrum. There was no correlation between a large second aditus and the size of hydrocele. A positive reaction to Rivalta and Runeberg test revealed that the contents of the solution in the hydrocele was exudative. Bacterial examinations were all negative. Histopathological examinations revealed that the maxillary antrum mucosa was normal, and that the hydrocele contained serous fluid that pooled in connective tissue.

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We examined the production of monoclonal antibodies(MoAb) against human γδT cells to understand the role these cells play in the pathogenesis of periodontal disease. Stimulation of human peripheral lymphocytes with solid-phase anti-CD3 antibody and soluble IL-2 produced a 100-500-fold increase that included about 50% γδT cells in the two-week culture. These γδT cells were used as an antigen to produce the MoAb. Ten MoAbs were isolated and one of them, MoAb 1, was characterized immunohistochemically using gingival sections with periodontal disease, and compared with commercially available anti-γδT cell antibody.

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Human squamous cell carcinoma(SCC) tissues were examined immunohistochemically and with immunoelectron microscopy to localize the cellular antigen of SCC. The reactions of the mouse monoclonal antibodies(MoAbs) E8 and P54 produced against this human oral neoplasia were investigated. Both formalin-fixed, paraffin-embedded sections, and unfixed, fresh-frozen sections were used in the experiments. At low magnification light microscopy the stained reaction products of both antibodies were observed over the entire circumference of the cell membrane of both the non-neoplastic and neoplastic squamous cells. Under high magnification light microscopy, and with electron-microscopy, the two antibodies were found to react in different areas of the cells. The E8 antibody reacted with the entire cell membrane circumference of both non-neoplastic and neoplastic cells, and granularity was observed in the reaction products of the cytoplasm. The P54 antibody reacted with areas of the cell membrane adjacent to the desmosomes of both non-neoplastic and neoplastic cells. This reaction was stronger in the neoplastic cells showing up as a patch-like structure in the cell membrane. These results indicate that electron microscopy and high magnification light-microscopy are necessary when examining cell membrane staining of monoclonal antibody reactions, and that the cell membrane antigenicity of neoplastic cells appears to be stronger and more widespread than that of non-neoplastic cells.

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We developed a highly sensitive detection system for human papillomavirus(HPV) in order to elucidate the localization of HPV in formalin-fixed, paraffin-embedded sections from squamous cell carcinoma(SCC) using in situ PCR(consensus primers: MY 09 and MY 11). Various parameters such as thermal cycler apparatus, pepsin treatment, PCR reagent, stringency, PCR reaction condition, immunohistochemistry were examined. Under optimal conditions in situ PCR analysis revealed the specific presence of HPV DNA in all cases of SCC and their localizations were observed in the nuclei and cytoplasms of koilocytes, SCC cells and epithelial cells as forms of integrated HPV DNA and episomes. These results suggest that the establishment of the highly detection system for HPV brings to the development of carcinogenesis reserch much more.

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In vitro corrosion of Type III gold alloy and Au-Ag-Pd alloy in the presence of cells and its effect on cell viability were examined. Both alloys were extracted for 3 and 7 days in four kinds of extracts; a medium containing two different cell populations and a medium with and without 10v/v% serum. Copper and zinc were selectively dissolved. However, no gold, platinum, palladium or silver was found in any extracts. Higher amounts of copper and zinc were found in the conditions containing cells or serum. Moreover, silver was detected in the extracts when Au-Ag-Pd alloy was extracted for 7 days in the presence of cells or serum. No metal elements were found in the cells adhered to either alloys. Cell viability on Type III gold alloy was almost the same as that of control, while that on Au-Ag-Pd alloy was markedly lower. The results indicate that the presence of cells might play an important role in evaluating the biodegradation of metallic biomaterials in tissues.

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The purpose of this study is to determine microsractually the early caries lesion process of the deciduous enamel. Deciduous enamel specimens(3 mm in diameter)were prepared from two types of extracted human deciduous teeth using a hollow core drill. One was complete root without root resorption. Another was completely with root resorption. The surfaces of two types of deciduous enamels were highly polished using the standard methods. These sample surfaces were observed by using AFM and then cut perpendicularly using a cutting saw to obserb by SEM. The AFM and SEM images resulted in as follows; 1)The surface enamel crystals of the sound deciduous canine was different with different root resorption. This difference of crystal size was resulted in enamel crystal growth; 2)Such a crystal growth influenced the formation of subsurface lesion at the deciduous enamel. ; 3)Early caries lesions occurring at the deciduous canine without root resorption might be extended subsurface lesion formation with the enamel crystal dissolution of lateral and upper side at the cave.

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The purpose of this study was to elucidate the serial changes in the mandibular arch width during basic mandibular movement, and the relationship between the condylar movement and the changes in the mandibular arch width. A linear variable differential transformer(LVDT) was used for measuring the mandibular arch width, and a six-degree-of-freedom jaw movement tracking device was used for measuring the mandibular movement(incisal point and condylar point). The subjects performed habitual opening movement, protrusive movement, and lateral movement. As a result, it was found that the mandibular arch width decreased according to the increase in the movement amount of the condylar point, and the maximum amount of decrease was 333.73±96.25μm during protrusive movement, 295.25±52.92μm during habitual opening movement, and 77.04±33.31μm during lateral movement, with a significant difference. The serial changes in the mandibular arch width that decreased according to the increase in the movement amount of the condylar point differed by the types of movements. These findings revealed that the amount of decrease in the mandibular arch width had a close relationship with movement amount of the condylar point in each movement path; however, the serial changes in the mandibular arch width differed by the types of movements.

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We attempted to obtain indexes for the objective evaluation of esthetic recovery in clinical prosthodontics, by analyzing the influence of complete dentures on the soft tissue in the lower facial region. We modified several dentures to determine how changes in the vertical dimension and modifications to the artificial teeth and flange areas changed esthetics. Facial measurements were done with a 3D sharp measurement system(VOXELAN, NKK, Tokyo, Japan). We found that placement of the teeth and modifications to the denture base significantly changed the lower facial soft tissues. This was reflected in the height of the lips, lip angle, nasolabial angle and the distance between the lip and the E-line. These items seem to be useful indexes of the lower facial soft tissue support. As the vertical dimensions were changed, significant differences resulted in the width of the mouth, height of the lip, lip angles, and surface area of the lips. The results suggest that these values can be used as indexes of the change in vertical dimension.

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The purpose of this study is to determine surface structure of deciduous enamel. Five of deciduous enamel specimens(3 mm in diameter)were prepared from extracted human deciduous teeth without or with natural white spot lesion using a hollow core drill. The surfaces were highly polished using a improved standard methods. Three surface of deciduous enamel without natural white spot lesion were covered half surface by nail vernish and then immersed 4 hours at 37 degree in demineralized solution to prepare artificial white spot lesion at a half of the surface. Another half of the surface was employed as a control of deciduous enamel. These sample surfaces were observed by using AFM. The AFM images showed the surface of natural and artificial white spot lesion of deciduous enamel increased crystal interspace as compared with a control. The AFM image with high magnification detected rectangle crystals at natural white spot lesion and square crystal at artificial white spot lesion as compared with round or oval crystal of control deciduous enamel. Based on these results, our improved method for polishing of deciduous enamel surface was suitable to observe the surface of deciduous enamel at crystal level by AFM. Deciduous enamel crystal at the surface of natural white spot lesion is different from crystal at the surface of artificial white spot lesion.

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Using SAMR1 and SAMP8 mice, we investigated the senescent changes of submandibular gland collagen. The extractability of soluble collagen by pepsin digestion was low(21.0%-13.2%), and decreased with senescence. The solubility with CNBr treatment was also very low(about 40%), and decreased with senescence. Our findings suggest that senile functional changes in the submandibular gland are characterized by collagen containing high cross-linkage.

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