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The elastic-plastic fracture toughness JIC of two titanium-zirconium-molybdenum (TZM) alloys with different kinds of grain boundary particles was estimated at elevated temperatures using the convenient JIC test method with a suitable depth of side-groove for determining the JIC at the maximum load point. It was found that the convenient JIC test method can be successfully applied to evaluate high temperature fracture toughness at least up to 1200 °C. The JIC values at temperatures ranged from 800 °C to 1200 °C were almost constant regardless of temperature, while the JIC values of the TZM with carbide particles were higher than those of the TZM with oxide particles. The TZM with different forging rates showed similar JIC values, which suggested the effect of forging rate would be not significant at high temperatures.

Background Dental caries inequalities still severely burden individuals' and society's health, even in countries where fluoride toothpastes are widely used and the incidence of dental caries has been decreasing. School-based fluoride mouth-rinse (S-FMR) programs, a population strategy for dental caries prevention, might decrease dental caries inequalities. This study investigated the association between S-FMR and decreasing dental caries prevalence and caries-related inequalities in 12-year-olds by Japanese prefecture. Methods We conducted an ecological study using multi-year prefecture-level aggregated data of children born between 1994 and 2000 in all 47 Japanese prefectures. Using two-level linear regression analyses (birth year nested within prefecture), the association between S-FMR utilization in each prefecture and 12-year-olds' decayed, missing, or filled permanent teeth (DMFT), which indicates dental caries experience in their permanent teeth, were examined. Variables that could explain DMFT inequalities between prefectures, such as dental caries experience at age 3 years, dentist density, and prefectural socioeconomic circumstances, were also considered. Results High S-FMR utilization was significantly associated with low DMFT at age 12 (coefficient -0.011; 95% confidence interval, -0.018 to -0.005). S-FMR utilization explained 25.2% of the DMFT variance between prefectures after considering other variables. Interaction between S-FMR and dental caries experience at age 3 years showed that S-FMR was significantly more effective in prefectures where the 3-year-olds had high levels of dental caries experience. Conclusions S-FMR, administered to children of all socioeconomic statuses, was associated with lower DMFT. Utilization of S-FMR reduced dental caries inequalities via proportionate universalism.

Aim: To assess the critical tooth number (CTN) required for prevention of subjective dysphagia caused by oral impairments and to evaluate the relationship between this CTN and mortality. Methods: The baseline study was performed with residents aged 40–89 years (n = 5 643; 2224 men and 3419 women) in Miyako Islands, Okinawa, in 1987. Dental examinations were performed by dentists, and subjective dysphagia was asked. We recorded the cause and year of death of participants who died during the next 15 years. Results: The average functional tooth number of participants with and without subjective dysphagia declined with age in both sexes. The CTN for each respective age group (40s, 50s, 60s, 70s and 80s) not including the denture group were 20.0, 17.5, 14.0, 11.8 and 10.1 in men and 19.0, 14.7, 12.7, 9.5 and 4.0 in women. These CTN were significant factors of 15-year mortality in both sexes (P

An association has been suggested between environmental tobacco smoke and oral disease. The present study examined the relationship between early childhood caries (ECC) and parental smoking, particularly paternal smoking, using records of 711 36-month-old children. The smoking status of parents as an independent variable was entered in the multivariable logistic regression model for caries experience as the dependent variable with confounders: sex, residential location, and possible risks of ECC such as order of birth, type of main drink, frequency of daily intake of sugar-containing snacks, daily toothbrushing by parents and use of fluoridated toothpaste. About 65% of children were caries free. Children whose parents did not smoke (CN), those in whom only the father smoked (CF), and those whose mother smoked regardless of the smoking status of the father (CM) comprised 33%, 33% and 34% respectively. The adjusted mean number [95% CI] of decayed teeth and caries experience prevalence for CN, CF and CM were 1.2 [0.8, 1.6], 1.6 [1.2, 2.0] and 2.1 [1.7, 2.5], and 25.6%, 35.3% and 45.7% respectively. The relationship between caries experience and parental smoking was significant on multivariable analysis. The adjusted OR [95% CI] of CF and CM relative to CN was 1.52 [1.01, 2.30] and 2.25 [1.51, 3.37] respectively. These results indicate the association of ECC with parental smoking, although the association with paternal smoking was weaker than with maternal smoking.

Background: To study how dental status can become a predictor of overall mortality risk. Methods: Community residents (n = 5730) over 40 years old in the Miyako Islands, Okinawa Prefecture, Japan were followed up for 15 years, 1987–2002. Functional tooth numbers were examined by dentists and overall mortalities of subjects with functional tooth numbers of

Objective: Various factors may be associated with edentulism in elderly people. Association of total tooth loss with smoking, alcohol intake and nutrition in non-institutionalised elderly Japanese was assessed utilising national database. Materials and methods: Records of independent surveys, the Survey of Dental Diseases (SDD) and the National Nutrition Survey (NNS) in 1999 were electronically linked using the household identification number. Results: Among the records of 6903 subjects in the SDD and 12 763 subjects in the NNS, 6805 records were successfully linked. Overall, prevalence of total tooth loss in adults was very similar in males and females at approximately 7.0%, and the smoking rate was 47.6% and 9.9% respectively. Total tooth loss was a rare phenomenon (

Background: A causal association between cigarette smoking and periodontal disease has been established. The present study examined the association between smoking and tooth loss using national databases in Japan.Methods: Records of the Survey of Dental Diseases and the National Nutrition Survey in 1999 were linked electronically using common identification. Records of 3,999 subjects aged older than 40 years were analyzed using logistic regression models, controlling for confounding factors, such as age, frequency of tooth brushing, body mass index, alcohol consumption, and intakes of vitamin C and E.Results: Prevalence of tooth loss in terms of having less than 19 existing teeth was 37.3% overall. Smoking rates differed in males (45.6%) and females (7.8%). The prevalence of tooth loss in nonsmokers, former, and current smokers was 28.5%, 38.6%, and 36.9% in males, and 38.6%, 34.3% and 38.9% in females, respectively. Adjusted means of existing teeth controlling for confounders by smoking status were 21.5, 19.7 and 18.2 in males and 19.0, 19.2 and 16.4 in females, respectively. The association of tooth loss was non-significant in former smokers but significant in current smokers: adjusted odds ratios (95% confidence intervals) relative to nonsmokers in males and females were 1.29 (0.92-1.80) and 0.86 (0.46, 1.60) for former smokers and 2.22 (1.61-3.06) and 2.14 (1.45-3.15) for current smokers, respectively. A dose-response relationship between lifetime exposure and tooth loss was seen (P for trend

Background and Objective: The association between cigarette smoking and periodontitis was examined employing two nationally representative samples of adults in Japan. Material and Methods: Data were derived from the Survey of Dental Diseases (SDD) and the National Nutrition Survey (NNS) in 1999. In the SDD, periodontal conditions were evaluated by calibrated dentists utilizing the Community Periodontal Index (CPI), whereas in the NNS, participants were interviewed on the basis of smoking status by enumerators. Among 6805 records electronically linked via a household identification code, 4828 records of individuals aged 20 yr or older were analyzed. Results: The prevalence of periodontal disease varied significantly by smoking status (p

BACKGROUND: There has been no nationwide study in Japan on reasons for extraction of permanent teeth. This survey was aimed to determine the reasons for extraction of permanent teeth in Japan.METHODS: Five thousand, one hudred and thirty-one dentists were selected by systematic selection from the 2004 membership directory of the Japan Dental Association. The dentists selected were asked to record the reason for each extraction of permanent teeth during a period of one week from February 1 through 7, 2005. Reasons for tooth extraction were assigned to five groups: caries, fracture of teeth weakened by caries or endodontics, periodontal diseases, orthodontics, and other reasons.RESULTS: A total of 2,001 dentists (response rate of 39.1%) returned the questionnaires, and information on 9,115 extracted teeth from 7,499 patients was obtained. The results showed that caries and its sequela (totally 43.3%, 32.7% and 10.6%, respectively) and periodontal disease (41.8%) were the main reasons for teeth extraction. Extraction due to caries or fracture was commonly observed in all age groups over 15 years of age, whereas periodontal disease was predominant in the groups over 45 years of age.CONCLUSIONS: Most of the permanent teeth were extracted due to caries and its sequela and periodontal disease. Prevention and care for dental caries for all age groups and periodontal disease for over middle age groups are required.J Epidemiol 2006; 16: 214-219.

日本歯周病学会会員の現在の喫煙状況および喫煙に関する考えを把握するために評議員を対象として質問調査を行なった。質問票を郵送し回答の上同封の封筒による返送を求め, その結果を分析した。回答が返送されたのは231名中145名で返送率は63%であった。年齢は40—50代が多く74%を占めた。所属は大学教員68%, 開業医25%, 勤務医4%, その他3%であった。喫煙状況については現在喫煙者13%, 元喫煙者39%, 非喫煙者48%であった。ニコチンの依存性については90%が肯定的であった。多くの疾患に喫煙が関連していると認識されており, 喫煙と歯周病との関連については94%が肯定的な考えを示した。歯科医師は禁煙指導をすべきという意見に80%以上の賛成が得られたが, 一方で禁煙指導の知識は十分とは言えないとする回答が43%であった。歯周病専門医の資格要件を非喫煙者とすることに賛成が79%を占めた。臨床医の約半数が患者の喫煙状況についての把握をしていた。喫煙状況は初診時に確認していることが多かった。また, 80%が重症な歯周病患者に喫煙者が多いと感じており, 88%が喫煙者は歯周治療で治りにくいと感じていることが示された。以上より, 回答が得られた集団では喫煙の歯周病への為害性を認識しており, 現在の喫煙率は比較的低いことが示された。また, 歯周病患者への禁煙指導の必要性を認識しつつも, 指導のための知識が不足している可能性が示唆された。

To assess the critical tooth number (CTN) required for prevention of subjective dysphagia caused by oral impairments and to evaluate the relationship between this CTN and mortality.The baseline study was performed with residents aged 40-89years (n=5,643; 2224 men and 3419 women) in Miyako Islands, Okinawa, in 1987. Dental examinations were performed by dentists, and subjective dysphagia was asked. We recorded the cause and year of death of participants who died during the next 15years.The average functional tooth number of participants with and without subjective dysphagia declined with age in both sexes. The CTN for each respective age group (40s, 50s, 60s, 70s and 80s) not including the denture group were 20.0, 17.5, 14.0, 11.8 and 10.1 in men and 19.0, 14.7, 12.7, 9.5 and 4.0 in women. These CTN were significant factors of 15-year mortality in both sexes (P0.05). The hazard ratios were 0.72 (95% confidence interval=0.55-0.93) in men and 0.71 (0.51-0.99) in women. In aged people, the minimum number of functional teeth needed to avoid subjective dysphagia might not be as high as in young people.

The effects of sex hormones on the in vitro chemotaxis of polymorphonuclear leukocytes (PMNs) and monocytes were investigated using fMLP as the chemoattractant. PMNs, monocytes, and plasma were obtained from heparinized peripheral blood of healthy adults. Chemotaxis of PMNs or monocytes treated with sex hormones were tested using 48-well chemotaxis microchambers. The correlation between sex hormone levels in plasma and the chemotactic ability of PMNs from the same donor was also investigated. The chemotaxis of PMNs was enhanced by progesterone, while it was reduced by estradiol. Random migration of PMNs was also enhanced by progesterone and reduced by estradiol. The effect of estradiol on PMN chemotaxis was inhibited by addition of antiestrogens or progesterone. Testosterone did not have a measurable effect on PMN chemotaxis. A significant positive correlation was found between the concentration of progesterone in plasma of females and PMN chemotactic ability in vitro. For males, there was no significant relationship between plasma levels of sex hormones and PMN chemotactic ability. Estradiol and testosterone levels in plasma did not correlate with PMN chemotactic ability. Sex hormones had no effect on the chemotaxis of monocytes. These results suggest that the altered PMN chemotaxis associated with gingival inflammation may be due to the effects of sex hormones.

Background: Oral function influences various general health and organ diseases. We wondered if physical complaints of unknown origin were related to oral function. Methods: Five thousand five hundred and eighty-four community residents (2206 men and 3378 women, aged 40–89 years) on the Miyako Islands, Okinawa Prefecture, Japan, were recruited for the baseline study in 1987 and followed up for 15 years. Physical complaints and functional tooth numbers were assessed for the baseline study in 1987 by dentists and followed up for 15 years. Physical complaints of unknown origin included shoulder stiffness, lower back pain, pain of upper extremity, pain of lower extremity, neuralgia, ear ringing, difficult of hearing, dizziness and sleeping difficulties. Results: Physical complaints were significantly associated with functional tooth number in the baseline study. There were no systematic differences between physical complaints and functional tooth number among different age groups. Physical complaints did not influence the survival rates in either men or women. Conclusion: Oral function may be related to physical complaints. Dental care may be one of the targets to treat these physical complaints of unknown origin.

Magnetism of iodine doped fluoro-aluminum phthalocyanine (AlPcF) film is studied by electron spin resonance (ESR) in two stable doping states: In State I, a doped AlPcF film is always in contact with saturated I 2 gas (AlPcF·I 4.0 ); In State II, a doped film is in no contact with I 2 gas (AlPcF·I 0.10 ). An antiferromagnetic transition is observed in both states. In State I in vacuum, the transition temperature depends on samples and the highest transition temperature observed is 160 K. In State II, it does not depend on samples and is 150 K in vacuum and 220 K at 1 atm. The occurrence of the magnetic transition indicates an existence of three dimensional magnetic coupling, i.e. interchain and intrachain couplings. An information about back charge transfer probability from I 3 - to AlPcF· + in State II is obtained from a degree of g anisotropy. With a help of this information, possible mechanisms of the interchain coupling are discussed.

Aim: To prospectively study how dental status with and without dentures could become a predictor of overall mortality risk. Methods: Five thousand six hundred eighty-eight community residents over 40 years old in the Miyako Islands, Okinawa Prefecture, Japan, were followed up for 15 years from 1987–2002. Results: We found that female subjects with less than 10 functional teeth and without dentures showed a significantly higher mortality rate than those with dentures. There was no significant difference of mortality rates in male subjects. There were no significant differences of mortality rates between subjects with 10 or more functional teeth with and without dentures. Conclusion: The present study suggests that dentures are one of the factors associated with mortality rates especially in female subjects with less than 10 functional teeth.

The purpose of the present study was to investigate the effect of the chewing gum containing egg-white lysozyme on gingivitis. Sixteen adults aged 18 to 26 years, who exhibited clinically slight gingivitis, were chosen for the study based on preliminary screening. The volunteers were randomly assigned to two groups of eight. They were directed to chew a piece of chewing gum containing 1% egg-white lysozyme or placebo for 5 minutes after each meal during 2 weeks. The experiments were performed in a double blind method. Oral examinations (probing depth, gingival score, bleeding score and plaque score) were carried out on day 1, day 8, and day 15 of the experimental period. All the subjects were instructed to continue their habitual toothbrushing. At the end of the experimental period, the volunteers answered a questionnaire about their subjective feelings and what they thought of the gum. The results were as follows.1) The probing depth, the bleeding score, and the plaque score in both groups decreased at the end of the period.2) The experimental group had a significantly larger decreace in the probing depth and plaque score than the placebo group, but there was not a significant difference in the gingival score between the two groups.3) Concerning the size, hardness, thickness, and taste of the chewing gum, most of the subjects of both groups judged them appropriate and favorable. With respect to the mouth condition, 6 of the placebo group noticed no change, while 4 of the experimental group answered that they felt a decrease in gingival bleeding.These results indicate that the lysozyme-containing chewing gum may be effective in the maintenance of oral health and that this gum may be acceptable to patients with gingivitis.

Background Various factors affect tooth loss in older age including cigarette smoking; however, evidence regarding the association between smoking and tooth loss during young adulthood is limited. The present study examined the association between cigarette smoking and tooth loss experience among adults aged 20–39 years using linked data from two national databases in Japan. Methods Two databases of the National Nutrition Survey (NNS) and the Survey of Dental Diseases (SDD), which were conducted in 1999, were obtained from the Ministry of Health, Labor and Welfare with permission for analytical use. In the NNS, participants received physical examinations and were interviewed regarding dietary intake and health practices including cigarette smoking, whereas in the SDD, participants were asked about their frequency of daily brushing, and received oral examinations by certified dentists. Among 6,805 records electronically linked via household identification code, 1314 records of individuals aged 20 to 39 years were analyzed. The prevalence of 1+ tooth loss was compared among non-, former, and current smokers. Multiple logistic regression models were constructed including confounders: frequency of tooth brushing, body mass index, alcohol consumption, and intake of vitamins C and E. Results Smoking rates differed greatly in men (53.3%) and women (15.5%). The overall prevalence of tooth loss was 31.4% (31.8% men and 31.1% women). Tooth loss occurred more frequently among current smokers (40.6%) than former (23.1%) and non-smokers (27.9%). Current smoking showed a significant association with 1+ tooth loss in men (adjusted OR = 2.21 [1.40–3.50], P = 0.0007) and women (1.70 [1.13–2.55], P = 0.0111). A significant positive exposure-related relationship between cigarette smoking status and tooth loss was observed (P for trend < 0.0001 and 0.0004 in men and women, respectively). Current smoking was also associated with the prevalence of decayed teeth (1.67 [1.28–2.20], P = 0.0002). Conclusion An association between cigarette smoking and tooth loss was evident among young adults throughout Japan. Due to limitations of the available variables in the present databases, further studies including caries experience and its confounders should be conducted to examine whether smoking is a true risk of premature tooth loss in young adults.

Objectives The study investigated the relationship between smoking in the household and dental caries in Japanese children using nationally representative cross-sectional data. Methods This study included 925 children aged 1-14 years. A child was considered to have decayed and/or filled teeth if a dentist diagnosed these conditions in deciduous or permanent teeth. Smoking in the household was defined as positive if someone in the household reported smoking cigarettes. Results No statistically significant relationship was observed between household smoking and caries experience. However, smoking in the household was independently associated with an increased prevalence of decayed teeth. The adjusted mean of filled teeth among children exposed to household smoking was higher than that among non-exposed children. Conclusions The results of the study failed to substantiate a positive association between passive smoking and caries experience in Japanese children.

The aim of this ecological study was to determine the association of the frequency of dental health activities conducted as public health service and sociodemographic characteristics with caries prevalence in Japanese 3-year-old children using data for each municipality as one unit. Data on caries prevalence in 3-year-old children in 2000 were obtained from 3,251 municipalities (almost all municipalities in Japan). Caries prevalence for each municipality was recalculated using the empirical Bayes estimation model to make adjustments for variations in municipalities with small numbers of children. Explanatory factors included annual frequency of dental health activities such as dental health education and topical fluoride application programs and various sociodemographic characteristics. Multiple linear regression analysis was applied to examine the associations between caries prevalence and annual frequency of dental health activities with adjustment of other sociodemographic variables. Variations in caries prevalence in municipalities with small populations became smaller after being adjusted by the empirical Bayes estimation model. Multiple linear regression analysis showed significant associations of caries prevalence with sociodemographic characteristics such as the proportion of residents with university degrees, total fertility rate, and the proportion of workers in the manufacturing industry (p < 0.001). Annual frequency of topical fluoride application showed a significant but relatively weak association with caries prevalence (p < 0.001), explaining only 0.8% of the total variation in caries prevalence, whereas no correlation was found between caries prevalence and annual frequency of dental health education. It was concluded that the effect of the fluoride application service on caries prevalence in 3-year-old children, although statistically significant, was of far lower clinical significance than sociodemographic characteristics.

In order to describe the relationship between mortality rate and extreme heat during the summer of 1999 in Hokkaido, we calculated the monthly age-adjusted death rates, average monthly mean temperature and average monthly high temperature for the years 1995 to 1999 in Hokkaido. The materials were derived from Statistics and Information Department, Minister's Secretariat, Ministry of Health, Labour and Welfare of Japan, Statistical Bureau Management and Coordination Agency Government of Japan and the Japan Meteorological Agency. Trends in the monthly age-adjusted death rates and temperature changes in the same period were analyzed. The highest average monthly high temperature for August and September (28.8 degrees C and 23.8 degrees C, respectively) occurred in 1999; the similar trend was observed in the highest average monthly mean temperature. In August 1999, there were 14 days with highest temperatures of 30 degrees C and over. The age-adjusted rate in August 1999 was significantly higher compared with those for the years 1995 to 1998 (p

“齲蝕予防は育児である”という言葉があるように, 乳幼児期における齲蝕には, 家庭環境, 特に母親が大きな影響力を持っていると言われている. 本研究では, 4～6歳の幼稚園児とその母親153組を対象に, 母子の性格と齲蝕との関連性について検討した。母子の性格検査は, 母親に対しては“YG性格検査用紙”を, 園児に対しては高木・坂本の“幼児・児童性格診断検査用紙”を使用して行った。また, 園児の齲蝕罹患状況については, 厚生省の分類に従い齲蝕罹患型 (O・A・B・C型) に分けたものを用いて以下に示す結果を得た。1) 因子分析法を適用し, 母子の性格特性 (上記性格検査の22項目) が, 4つの共通因子によってほぼ説明しうることがわかった。第1因子は子供安定性の因子, 第2因子は母親消極性の因子, 第3因子は母親不安定・不適応性の因子, 第4因子は子供社会性の因子と名付けられた。2) 母親消極性の因子 (第2因子), 子供社会性の因子 (第4因子) と齲蝕罹患型との関連性は認められなかった。一方子供安定性の因子 (第1因子) については, さらに検討が必要と思われた。3) 性格的にはむしろ問題と思われる不安定・不適応性 (第3因子) の高い母親の場合, かえって齲蝕予防の実践が効果的に行われていることが示唆された。

The present study involved cultural and microscopic characterization of the subgingival microorganisms of pubertal children with gingivitis. Samples were obtained from eight children 12-14 years of age. Gram-positive organisms made up 56% of the isolates and included mainly Actinomyces israelii, Actinomyces naeslundii. Gram-negative anaerobic rods constituted 25% of the isolates and Bacteroides intermedius (9.7%) was most predominant species. The selective media permitted significantly lower recovery of Actinomyces spp. and Capnocytophaga spp. than nonselective blood agar medium. However, sixty-nine percents of isolates were cultured on the selective media employed in the present study. These results suggest that the subgingival microflora of gingivitis in pubertal children may be similar to those of adult gingivitis and that the use of these six selective media makes it possible to enumerate predominant cultivable microorganisms in subgingival area of pubertal children with gingivitis.

The purpose of this study was twofold. The first objective was to measure the periodontal status and perceptions of oral health in adolescents. The second objective was to determine the effects that a program of dental health education would have on their periodontal status and perceptions of oral health. The dental health education with a 90-minute lecture had been given to eleventh-grade students (352) in the previous year. The dental health education program was not carried out in tenth-grade students (442) yet. The oral examination was performed by a dentist for both grades. The examination time was about ten seconds per person. The students' periodontal status was scored as "excellent (+2)," "good (+1)," "questionable (0)," "poor (-1)," or "very poor (-2)" according to the criteria of an Oral Rating Index (ORI) System proposed by the present authors. The level of students' perceptions was assessed by the cognition score of our dental health test (10 items concerning dental attitudes and behavior). Main results were as follows: 1. Only 6% of the 10-th grade students were judged as having "excellent (+2)" oral health. Thirty-six percent were "very poor (-2)" or "poor (-1)" periodontal status. 2. The mean cognition score and the mean ORI score of the 11-th grade students were significantly greater for each sex group than those of the 10-th grade students. 3. The cognition score showed a clear relationship to the ORI score in each grade and in all. The behavioral component of the cognition score was more closely related to the ORI score. These findings suggest that the dental health education contributes to the improvement of periodontal status as well as that of perceptions. Furthermore, the ORI may be utilized for a screening system to evaluate adolescents' periodontal status quickly and effectively.

It is believed that gingivitis at puberty is exaggerated by alterations of the hormonal balance. We have suggested that estradiol promotes the gingivitis at puberty while progesterone reduces it (J. Hiroshima Univ. Dent. Soc. 19: 1987). But the mechanisms of these hormones which influence gingival inflammation are not known yet. Therefore, we hypothesized that one of the possible mechanisms of sex hormones on gingival inflammation is through their action on polymorphonuclear leucocytes (PMNs) function because PMNs play an important role in periodontal disease. The purpose of this study was to investigate the effect of sex hormones on PMNs function, especially their migration in vitro. PMNs and plasma were obtained from heparinized peripheral blood of 23 healthy adults. PMNs were preincubated at 37 degrees C for 15 minutes with progesterone or 17 beta-estradiol at designated concentrations. After preincubation, PMNs migration was measured using 48-well chemotaxis micro-chamber with N-formyl-methionyl-leucyl-phenylalanine (FMLP) as chemoattractant. The levels of estradiol and progesterone in the plasma were determined using Direct Radioimmunoassay Kits and the correlation between sex hormone levels and PMNs migration was investigated. PMNs migration to 10(-6) M FMLP was enhanced significantly by progesterone at the concentrations of 200 ng/ml while it was reduced by estradiol at 0.4 ng/ml and 2.0 ng/ml. Random migration of PMNs was enhanced significantly by progesterone at 20 ng/ml while it was reduced by estradiol at 0.4 ng/ml. Significant positive correlation was found between progesterone level in plasma and the PMNs migration in vitro. Estradiol level in plasma did not have any correlation with the PMNs migration in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

Gingival conditions of 1323 junior high schoolchildren aged 12-15 were examined, and 132 children who had either healthy gingivae or severe gingivitis were called to the clinic. More precise examination of gingivitis was performed by assessment of Jackson's gingivitis index (G.I.), probing depth (P.D.), and bleeding on probing. Whole saliva was collected, and the salivary concentrations of estradiol, progesterone, and testosterone were determined by radioimmunoassay. Subgingival bacterial plaque was sampled from 36 children, and total bacterial counts and morphological differentiation were performed under a phase-contrast microscope. For statistical analysis, both males and females were divided into two groups according to the concentration of each sex hormone and subgrouped by the results of clinical examinations. Chi-square analysis using 2-by-2 tables was performed to determine the relation between salivary steroid hormone levels and gingival inflammation. The results suggest that unbalanced secretion of certain hormones might be one of the factors promoting gingivitis at puberty.

A criterion was established in a previous study to detect the relapse of adult acute leukemia in its early stage, i.e., when lymphocytes in peripheral blood increased over 45% of the leukocytes during the maintenance therapy, bone marrow puncture was immediately performed to examine the leukemic cells. By this criterion the relapse was detected earlier than by other criteria. To study the effect of early detection of the relapse in adult acute leukemia on the results, the second remission rate and the survival time were compared between the following groups. Group I consisted of 11 patients, whose relapse was determined by our criterion. Group II consisted of 8 patients whose relapse was determined by the appearance of leukemic cells in peripheral blood. The second remission was accomplished in 7 of 11 patients in Group I (64%) and in 1 of 8 in Group II (13%) (p less than 0.05). The mean (+/- S.D.) duration of complete remission in Group I was 9.7 +/- 7.8 months and not significantly longer than the value in Group II (5.3 +/- 3.9 months). The interval from relapse to death was 10.3 +/- 5.9 and 6.1 +/- 3.8 months in Groups I and II, respectively. The interval from relapse to death of 7 patients who accomplished the second remission in Group I was 12.5 +/- 5.5 months. This interval was significantly longer than in Group II (p less than 0.02). The mean survival time was 22.2 +/- 9.6 months in Group I and 13 +/- 2.5 months in Group II. The mean survival time of 7 patients accomplished the second remission in Group I was 26. 7 +/- 9.4 months which was significantly longer than in Group II (p less than 0.01). The results showed that our criterion to detect relapse in the early stage was effective for prolongation of the survival time in adult acute leukemia.