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Volume 31 (1981 - 198･･･
- Issue 5 Pages 400-
- Issue 3 Pages 174-
- Issue 2 Pages 74-
- Issue 1 Pages 13-
Volume 31, Issue 2
Displaying 1-9 of 9 articles from this issue
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Kakuya ISHIDA1981 Volume 31 Issue 2 Pages 74-89
Published: 1981
Released on J-STAGE: July 27, 2010
JOURNAL FREE ACCESSThe effect of fluoride on bone metabolism was studied in rats. Since the urinary hydroxyproline (OHPro) is a good indicator for the level of bone resorption, OHPro in urine was mainly studied in rats exposed to chronic doses and/or acute doses of fluoride. As supplementary indicator, additional analyses were also done: calucium, phosphate and fluoride for urine; alkaline phosphatase activity, calcium and fluoride for serum; and analyses of those mineral contents and/or soft X-ray analysis for femurs.
In the experiment with chronic doses of fluoride, lowered urinary levels of free and total OHPro were seen in the higher dose groups (100 and 200 ppm F). This finding indicates that bone resorption and collagen synthesis are depressed. In the medium dose groups (10 and 50 ppm F), however, high urinary levels of free and total OHPro were seen only the 15th experimental day, indicating a temporal acceleration of bone resorption. Further, an inter esting finding was seen in a lower dose group (1 ppm F): that is, a rising tendency in the urinary level of free OHPro was seen in this group. It may be suggested that the bone metabolism can be activated by optimum fluoride.
On the other hand, abrupt and temporal bone resorption at the site of high metabolic activity may occur.
No significant changes in serum alkaline phosphatase activity, serum calcium, urinary phosphate and urinary calcium were observed.View full abstractDownload PDF (4339K) -
Naohiko INOUE, Ching Hui KUO, Gakuji ITO, Tetsuya KAMEGAI1981 Volume 31 Issue 2 Pages 90-97
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSThe incidence of dental diseases would be expected to rise as frequency of tooth to denture base discrepancy becomes higher, because the discrepancy seems to have pathogenetic influence on malocclusion, dental caries, and other related disorders. By studying incidence and seriousness of dental diseases in each historic age, therefore, it may be possible to obtain pathogenetic information on dental caries, to estimate the degree and extent of reduction of human dentition, and even to discuss evolution and civilization.
From this point of view, we have already reported on dental caries and some other diseases in Japanese remains from the Kamakura era, and conclusively pointed out that the degree of the discrepancy was not so dominant in that era as in the modern age, but it seemed firmly to exsist, with pathogenetic influence on dental caries. In the present paper, incidence and specificity of dental caries, and occlusal and proximal attritions observed in Japanese remains from the later Jomon period are reported. We also discuss the degree and extent of the discrepancy, its pathogenetic role in dental caries, and the food and eating behavior in comparison with those in the Kamakura and modern ages.
The materials used were 89 maxillae and 102 mandibles with permanent or mixed dentition, selected from 327 Japanese skulls mostly from the later Jomon period, stored in the University Museum, The University of Tokyo.
The frequency of dental caries in the Jomon period was almost the same as in the Kamakura era, but much lower than in the modern age. However, its seriousness was much worse than in the Kamakura era, and almost the same as in the modern age, as indicated from the fact that the carious teeth are distributed more frequently in C3 and C4 than in C1 and C2.
The pathogenetic pattern of dental caries in the Jomon period is different from that in the Kamakura era and in the modern age in the following points. 1. The distribution of carious teeth is biased towards the posterior teeth, but not so dominantly as in the Kamakura era. 2. Carious teeth are distributed even in the anterior region. 3. The rate of carious teeth for the third molar does not exceed that for the first molar in both maxilla and mandible. From these facts, the dental caries in the later Jomon period seems to be of environmental pollution type, while it is of the discrepancy type in the Kamakura era and of a combination type in the modern age.View full abstractDownload PDF (1373K) -
Fusako ONO, Kiichiro INOUE, Yuzi OOTSUKA, Keisuke NUMATA, Shigeru YAMA ...1981 Volume 31 Issue 2 Pages 98-107
Published: 1981
Released on J-STAGE: July 27, 2010
JOURNAL FREE ACCESSWe compared the dental plaque formation indicies on the central incisors and first molars in a total sample of 222 elementary school pupils, consisting of 110 boys and 112 girls.
When the plaque index was 0 on 1 in terms of Greene and Virwillion schemes, the incidence rate was approximately 25% when 6| was also 0. The other cases fell in the categories of degrees 1, 2, or 3. Tindings in the cases of 1, 1, and 1 were similar to those of 1.
In all elementary schools, statistical differences were found for the right and left upper and lower central incisors and between the first molars. A significant correlation (r) was found between the central incisors and first molars in two elementary schools, and the two other schools had a slight indication of statistical correlation.
When elementary school pupils are made the subjects of this kind of study, doubt remains whether or not the anteriors are appropriate to represent the entire jaw. It needs to be pointed out that, in carrying out a study of dental brushing of elementary school pupils, it is necessary that not only the plaque condition of the anteriors but also that of the molars should be equally studied.View full abstractDownload PDF (1477K) -
Koji OZAWA1981 Volume 31 Issue 2 Pages 108-130
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSThere is a great deal of literaturature on the sterilization of fingers of physicians and dentists beginning with the pioneer effort of Fürbringer and the development of various sterilizers, sterilization methods and length of sterilization time.
This is particularly true of clinical dentistry where the dentists come in contact with their patients with naked hands, this situation leading to a possibility of bacterial contamination from dentist to patients or from patients to dentist. For this reason, the present study was undertaken with questionnaires to investigate the finger contamination of dentists and, at the same time, to examine the sterilization methods currently in use in dental clinics.
2 obtained the following results.
1. The sterilization effects after 5 minutes were 98.5% for 0.1% benzalkonium chloride, 97.8% for Hibisclub, 95.4% for 0.02% chlorhexidine, and 90.5% for 2% creosol.
2. Regarding daily variations in bacterial colonies, on the days when the number of outpatients was relatively small, there was a tendency toward increased bacterial colonies. When the fingers were not washed with soap before a dental treatment, a positive reaction was seen in DHL media. When stained by the Gram's method, there were some Gram-negative lactobacilli and Gram-positive streptococci.
3. As regards finger contamination in terms of different dental treatments, it was 15.6times in crown preparation 13.9 times in the enlargement of pulp cavity, 12.8 times in scaling, 10.0 times in the installation of crowns, 9.4 times in inlay preparation, and 9.2 times in dental extraction.
4. The questionnaires concerning finger contamination sent to practising dentists gave the following responses.
(1) The majority of them used cresol for sterilizing purposes followed by benzalkonium chloride, chlorhexidine, and benzethonium chloride. There were some dentists who used soap alone.
(2) As for the length of sterilization, 41.7% immersed their fingers in a disinfectant for about 5 seconds, and the rest for about 2 seconds, 15 seconds, or longer than 30 seconds.View full abstractDownload PDF (3850K) -
Makoto SATO, Fumiko OZAKI, Shogoro OKADA, Takashi TSURUMIZU, Masao ONI ...1981 Volume 31 Issue 2 Pages 131-136
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSMutated sub-strains of Str. mutans were prepared from strain 10449 (human type) and strain RC-20 (rat type) with the nitrogen mustard mutation method. The mutant which produced a great deal of insoluble glucans was named phase I, and the mutant which failed to form insoluble glucans was named phase III. Four mutants (10449-phase I, III and RC-20-phase I, III) were examined for cariogenicity with an experimental caries model using rats.
At weaning, the rats were given 200 μg/ml streptomycin-sulfate water during two days. The rats were divided into four groups and were challenged with the 4 mutants of Str. mutans once a day for eiyht days. All animals were fed with the cariogenic diet (6PMV) and distilled water for 30 days after weaning. During this period, the residual Str. mutans in the mouth of the rats was examined. The upper and lower jaws with teeth and the blood were taken from sacri ficed animals. There was more Str. mutans remaining in the rats' mouth in the phase I sub-strain than in the phase HI sub-strain of both 10449 and RC-20 strains. Although there was no significant difference between the amount of Str. mutans 10449-phase I and RC-20-phase I remaining, significantly more carious lesions were discovered on the molars of the rats in the RC-20-phase I group. The rats of the 10449-phase I group had many more carious lesions than the 10449-phase III group. However, the RC-20-phase I group had a caries score nearly equal to that of the RC-20-phase III group. During the experimental period, a rat-type strain of Str. mutans, which seemed to be an indigenous organism within the rats' mouth, was detected in the RC-20-phase III group. It seemed that the poor ability of the RC-20-phase III strain to become established induced the prevalence of indigenous Str. mutans, and carious lesions developed from these indigenous organisms.
The serum collected from the rats in the four groups had a similar level of agglutinating titer against RC-20 or 10449 whole cell antigen.View full abstractDownload PDF (2532K) -
Youichi IIJIMA1981 Volume 31 Issue 2 Pages 137-150
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSThe mode of the release of uptaken fluoride in enamel was examined in vivo at a depth of ca. 0.5-50 μm in specimens of human exfoliated deciduous teeth after APF application (0.9% F, pH 3.6) at different times. Rapid decrease of uptaken fluoride occurred in vivo within 6 to 24 hours, after which the remaining fluoride (2, 000-3, 500 ppm) was retained one month after APF application at a depth of 0.5-2.4 μm from the surface enamel. The innermost uptaken fluoride levels (at ca. 20-50 μm) of APF treated enamels, however, were not statistically higher than those of untreated enamels. Prolonging the application time greatly increases the fluoride penetration to the surface enamel. A 1 min application reaches the first layer (1.5μm), a 2 min application, the second layer (4.2μm), a 3 min application the third layer (10.6 μm), and a 5 min application the third layer (12.4 μm). Fluoride treatment markedly reduced the enamel solubility by about 50 % when compared with the control groups in determining of dissolved calcium levels obtained from the outermost enamel layers.View full abstractDownload PDF (4239K) -
Mitsuo TSUKADA, Masaki IWAKURA, Yoshihiro SHIMADA1981 Volume 31 Issue 2 Pages 151-157
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSThis study was undertaken to determine the amount of fluorine that remained in the mouth after the topical application of fluoride and to survey whether the topical application of fluoride induced any unpleasant symptoms by using a questionnaire. A total of 44 females aged 18 to 27 years, who attended a dental hygienist school in Sendai City, participated in this study. Using the double blind method, topical applications of both 2% NaF solution and placebo (normal saline solution) were made at an interval of 5 days. The subjects were instructed to apply 2ml of the solution and to use a cotton applicator according to a modified Muhler's technique. After the topical application was over, the residual solution, the cotton applicators and cotton rolls used for treatment and the saliva secreted during treatment were all collected individually. The fluorine content of these samples was determined with a fluorine-ion electrode. The mean amount of residual fluorine in the mouth was 1.83mg per person, ranging from 0.70-3.19mg, and 0.037mg per kilogram of body weight, ranging from 0.012-0.067mg.
Two days after the treatment, a questionnaire survey was also carried out and anyone who complained of any unpleasant symptoms was interviewed. There was no statistically significant difference between the two kinds of topical solution. When the mean amount of residual fluorine per kilogram of body weight was compared between the group complaining of unpleasant symptoms and the other, there was no significant difference but the latter showed a higher value than the former. The majority of those that complained of unpleasant symptoms referred to the strain and fatigue induced by the clinical practice.
From these findings, it was assumed that the occurrence of unpleasant symptoms was caused by the mental and physical stress involved with clinical practice rather than by acute fluoride poisoning by injestion.View full abstractDownload PDF (1340K) -
Masao ONISI, Fumiko OZAKI, Fusako YOSHINO, Yoshiko MURAKAMI1981 Volume 31 Issue 2 Pages 158-162
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSFive groups of 20 Wister pure strain rats were fed on the same caries inducing diet 6PMV and excepting one control group, four groups were given drinks of the same fluoride ion strength of 10ppm prepared from NaF solution and tea infusion diluted with 10ppm NaF solution. After 30 days tea drinking resulted in more effective caries reduction than the NaF solution, and the reduction was in inverse proportion to the dilution of the tea infusion, suggesting that it contains many biologically active substances and possesses physicochemical properties for caries prevention.View full abstractDownload PDF (644K) -
1981 Volume 31 Issue 2 Pages 172
Published: 1981
Released on J-STAGE: March 02, 2010
JOURNAL FREE ACCESSDownload PDF (200K)
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