The purpose of this study was to evaluate the VLC Dycal (visible light cured composite-calcium hydroxide material) to see whether it is suitable or not as a direct or indirect pulp capping agent for clinical use by means of the cell culture test. Two light cured composite resins, P-30 and Silux, and also Dycal and Ca(OH)₂were used as a control for a comparative cytotoxicity test with VLC Dycal. All test materials were put into the glass tubes(4mm diameter×1mm high), then illuminated for 10,20,30,40,50 and 60 seconds through a matrix strip with direct contact with a Prisma-light source (L. D. Caulk), just before testing. Fibroblasts,5 ml of 1×10⁵cells per ml in Eagle' s MEM medium with 10% FCS, penicilling (100 U/ml) and streptomycin (100μg/ml) were evenly seeded on a cover glass in a tissue culture dish and incubated for 24 hours at 37°C in a humidifled atomosphere of a 5% CO₂in air. After 24 hours, the medium was replaced with 5 ml of agar overlay medium consisting of 10% FCS, Eagle's MEM medium and 1.5% agar. Glass tubes (n=8) filled with the test materials were placed at the center of the agar, and incubated fbr 24 hours in 5% CO₂in air at 37°C. After 24 hours of incubation, the cover glass was removed and the cells were fixed in 10% neutral formalin and then stained by H. E. to differentiate the areas of affected and unaffected cells beneath the test specimens. The affected area was quantitatively determined using an image analysis system.

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The study was undertaken to examine the changes in humoral IgM, IgG and IgA antibodies and splenic plaque forming cell responses against Streptococcus sobrinus 6715 in rats infected with the same mutans streptococci.
The serum samples were collected every week for 24 weeks after infection (20 day old, Sprague Dawley rats). Humoral anti-S. sobrinus 6715 IgG and IgA antibodies were determined by an enzyme-linked immunosorbent assay. In the separate experiment, rat splenic IgM, IgG and IgA anti-trinitrophenyl (TNP)conjugated S. sobrinus plaque-forming cell (PFC) responses were also determined from 1 to 12 weeks after the infection.

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The aim of this study was to examine the Temporomandibular. Joint of the thirty-eight adolesent subjects with Temporomandibular Joint Dysfunction Syndrome by means of Fuji Computed Radiography System (FCR).
The following results were obtained:
1) It was indicated that the frequency of occurance of the backward on the condyle position to fossa in the group with signs of TMJ Dysfunction was higher than the group without signs. Also it was suggested that the central position was a good position as the goal for improved position.
2) The revealed frequency of morphorogical abnormality of condyle in the group with signs was higher than the group without signs.
3) Internal derangement of meniscus was associated with signs of TMJ Dysfunction. In particular, sound and pain was definitly associated with the internal derangement.
4) The organic abnormal change (morphological abnormality of the condyle and internal deragement of meniscus) in the TMJ of adolesent patients with the TMJ Dysfunction Syndrome was found.

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The aims of this study was to clarify the role of masticatory and occlusal malfunction in causing the Temporomandibular joint (TMJ) Dysfunction Syndrome in adolesents.
We examined the relationships between masticatory and occlusal malfunction and signs of the TMJ dysfunction by using the number of interocclusal points, occlusal interference, the dental arch models and the electromyographs. In particular, the electromyographs was examined by comparison between with at the first examination and after the adjustment of occlusal relations.
The subjects were thirty-nine out patients with the TMJ Dysfunction Syndrome.

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The affects of acetic buffers on the crystallinity of an enamel apatite were examined in the present study. Dual aspects, crystallite size and lattice imperfection related to the crystallinity were analyzed by the process of Variance and Fourier analysis based on the X-ray diffraction line profiles. For this purpose both enamel apatite and synthetic hydroxyapatite were analyzed through acetic acid buffer decalcification, and comparison was made. In addition to the analysis, morphological change of the apatite after acid decalcification was observed by a transmission electron microscope (TEM).

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FluorEver® is one kind of fluoride releasing composite resin. The first aim of this study was to investigate the amount of fluoride released from FluorEver. The second aim of this study was to determine the uptake of fluoride with bovine enamel, which was immersed in distilled water for 28 days in contact with FluorEver, compared with Fuji Ionomer® cement which released fluoride.

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The purpose of this study was to investigate the influence of the structural difference of the color measuring instruments and the background colors on the chromatical values of the composite resins.
Composite resin disks which were 10 mm in diameter and 1 mm and 2 mm in thickness, and made by the light-cured composite resin Silux Plus (3M Co. ) were chromatically measured.
The colors of the composite resin used in this study were universal, yellow, dark-yellow and light. The color measuring instruments used in this study were the Murakami Color Research Laboratory Fast Spectrophotometer CMS-500 used with the Flexible Sensor FS-1, FS-2 and FS-3, and the Murakami Color Research Laboratory Color Difference Meter CD-270 used with the Improved Light Guide CD-270. The diameters of the head which receives the light from the object were: FS-1 (2 mm), FS-2 (3 mm), FS-3 (5 mm) and Improved Light Guide CD-270(2 mm).

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With a view to finding out how the dental hygienist looks at and recognizes the changes in facial expression and behavior of a mother who is staying by her child just receiving dental care in the treating room, actions which the mother takes near her child were recorded and subjected to observation by a dentalhygienist apprentice.

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An analyzing system of multiple points for mandibular movements using Selspot was developed in this study. This measuring system is able to analyze simultaneously the movements of multiple required points in three dimensions, and was proved to be sufficient for use with young children because of the small burden imposed on them while taking measurements. Regarding the accuracy of this system, a method to correct the three dimensional distortion of the output values was devised, and a computer program was developed for this method. Therefore, the three dimensional distance between input values and corrected values was squeezed to 60μm on the average for 80 points which were arrayed in the three dimensional lattice within the range for measurement. By using this measuring system, lateral excursions from the centric occlusion were measured in 9 children (3 boys and 6 girls) with -primary dentition. The distance and direction of movements were then calculated around 5 analyzed points on their lower dentition (incisal point, right and left primary canines, right and left primary second molars). For comparing each movement, lateral excursions were standardized at the distance of 2 mm and 4 mm for which the incisal point moved.

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The purpose of this study was to assess the relationship of nutrition and dietary habits to gingivitis, dental calculus deposit and dental plaque adhesion in high school students.
The subjects were 16 third-year students (7 males and 9 females) at a high school in Tokyo. Dietary investigation was made for 4 days from Sunday to Wednesday. Conditions of gingivitis and dental plaque adhesion were examined concerning the labial aspects of 6 anterior mandibular teeth and the condition of the dental calculus deposits of 4 mandibular incisors was examined with respect to their lingual surfaces, then index scores were given according to the severity.

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Mastication has attracted considerable attention in recent years for its effects on the postnatal growth and development of the mandible, brain, salivary glands and other organs in children. In this study, the relationship between mastication and growth and development of the salivary glands was examined, because the salivary glands are rich in growth factors and many kinds of biological polypeptides, and have endocrine and exocrine actions and effects, on the growth and metabolic rates in developping animals.
The experiment utilized two groups of male mice, a control group fed a solid diet, and an experiemntal group receiving the paste diet ad lib.
In the experimental group fed the paste diet, the increase of the tissue weights and the contents of DNA and RNA in the parotid and submandibular glands were lower than those of the control group. Also the rise of amylase activity in the parotid glands was depressed.

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The purpose of this study was to examine missing anterior teeth and posterior teeth for possible differences according to the where the teeth were missing site, a comparison was made between children with such defects and those with relatively good occlusion.

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The purpose of this paper was to investigate the actual status of environmental and oral health conditions prior to and at the first visit of the outpatients who visited the pedodontics clinic of Tohoku University Dental Hospital during the period from April 1981 to May 1986, and to compare them with the results of the same kinds of investigation carried out 10 years ago.
The subjects were 895 children, with questionnaires being filled out by their mothers.

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The purpose of this paper was to investigate the correlation between the daily habits of eating and tooth-brushing and the prevalence of dental caries in the outpatients who visited the Pedodontics Clinic of the Tohoku University Dental Hospital during the period from April 1981 to March 1986.
The subjects were 877 individuals with questionnaires which the mothers had filled out.

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This study was to evaluate clinically low viscosity composite resin. The subjects of the present study were 121 children aged 2 to 10 years who visited the Pedodontic clinic of Tohoku University Dental Hospital and 53 children aged 2 to 8 years who visited the clinic of the general practitioners in Sendai. A total of 451cavities (343 at the clinic of the University Hospital,108 at the clinic of the general practitioners) were treated with Clearfil SC-II (Kuraray). The observation period varied from 1 month to 33 months after treatment. The restorations were examined with regard to spacing or stepped abrasion in the marginal region of the fillings, fracture, loss, attrition and discoloration of the fillings, and recurrent caries and/or pulpal involvement of the treated teeth. The following findings were obtained.

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Root resorbing of deciduous teeth is a general phenomenon during eruption of the permanent teeth. In the present study, we tried to clarify the activeoxygen metabolism of root resorped granulated tissues.
Granulated tissues were obtained from two fresh mandibles of young bovine about 1 year old undergoing root resorption. Cu-Zn-Superoxide dismutase (SOD), Mn-SOD, Lactate dehydrogenase (LDH), and concentration of lipid-peroxidated products were determined on the supernatants from homogenized tissues.
We obtained the following results.
1) Cytosolic Cu-Zn-SOD activity did not elevate as compared to control tissues.
2) Elevation of mitochondrial Mn-SOD activity was observed in granulated tissues.
3) LDH activity did not elevate as compared to control tissues.
4) Lipid-peroxidated products in granulated tissues showed high concentration as compared to control tissues.
Based on the above, we specurated that the active-oxygen metabolism in the root resorped granulated tissues, at least in mitochondria, was elevated.

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The purpose of this study was to investigate the change of frequency components of EMG (electromyograph) signals obtained from masticatory muscles in term of the development from deciduous mixed and permanent dentition using FFT (Fast Fourie Transform) algolism.
A total of one hundred and fourty subjects who had no oral dysfunction were subjected. The subjects were devided into four groups: deciduous dentition (designated as G1), early mixed dentition (designated as G2), late mixed dentition (as G3) and permanent dentition (as G4). EMG signals were taken from the right masseter and temporal muscles using bipolar surface electrodes during tooth tapping, clenching in the intercupsal position and maximum biting and EMG were recorded on magnetic tape (FM data recorder).

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The Ehlers-Danlos syndrome is a hereditary disease of the connective tissue, characterized by tendencies of hyperextensibility and fragility of the skin, and hypermobility of the joints.
We are reporting in this paper on a 4 year,4 month old boy with the Ehlers-Danlos syndrome, Type III.

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The total number of subjects was 2754 children (1354 boys and 1402 girls), who visited the Pedodontic Clinic of Kyushu University during the 5 year period from April 1st 1981 to March 31th 1986. We investigated the actual conditions of patients who complained of occlusal disharmony and who were ascertained to be associated with occlusal disharmony.

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The two cases with the transposition of the teeth were treated orthodontically. One was a case in which the teeth which had changed places with each other were aligned in irregular sequence, the other was one with the teeth which had erupted at the unusual position were repositioned in order of the tooth number. Those causes and some problems involved in diagnosis and treatment were discussed.

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We conducted a radiographic follow up and discussion concerning 125 primary teeth (46 boys and 24 girls), which were random samplings from all primary teeth which had been treated by pulpotomy with Formocresol (Pulpac V) during the period from January 1980 to December 1985 at the Pediatric Dentistry Clinic of the School of Dentistry, Hiroshima University. For the follow up examination, we used only the radiograms which were radiographically available.

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16 cases of odontoma (male: 12, female: 4) in young patients from 1 year 2 months to 14 years of age at the Pedodontic Clinic of Niigata University Dental Hospital in a recent 9 year period were investigated clinically.
As for the pathologic histology,12 cases were of the compound type,2 were of the complex type,1 was of the intermediate type between compound and complex, and 1 was of ameloblastic fibro-odontoma type.
9 cases occurred in the maxilla,7 cases occurred in the mandible. Most of the compound type were observed in the area of the maxillary incisors and cuspids, and the complex type cases were noted in the anterior part of the maxilla.
In many cases, there were clinical symptoms such as retarded eruption. Some cases of odontoma in children were small in scale and showed a low degree of calcification. Therefore they showed a tendency not to be found out at radiograph, and it is difficult to diagnose them as odontoma.
By finding odontoma prematurely and removing it in time, the retarded eruption teeth were able to erupt spontaneously or to be guided to a normal position.1

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