Michiko Nishimura

Postural stability and occlusal status among Japanese elderly

BACKGROUND There are still no data available on the relationship between postural stability and occlusal status among the elderly. OBJECTIVES To examine relationships between postural stability and occlusal status through a cohort study among elderly Japanese. METHOD Oral examination, occlusal status, postural stability and a questionnaire were conducted and given to 87 community-dwelling Japanese at enrolment. RESULTS The average occlusal pressure of the female group was statistically higher than the male group while average occlusal pressure and postural stability length were lesser in the group with more remaining teeth. Postural stability area and number of remaining teeth showed statistically significant correlations. Postural stability length was lesser in the group with strong occlusal force. Furthermore, the number of decayed teeth was fewer in the good hygiene group. CONCLUSIONS This study identified a close relationship between occlusal status and postural stability of Japanese older individuals. Occlusal hypofunction was observed more in those with occlusal problems, and a decrease in their occlusal functions resulted in postural instability.

In vitro antibacterial activities of Scutellaria baicalensis Georgi against cariogenic bacterial

Abstract Scutellaria baicalensis Georgi has been used for thousands of years in traditional Chinese medicine practice for several purposes. It possesses several biological activities such as anti-oxidative, anti-inflammatory, antibacterial and antiviral activities. Although the antibacterial activity of Scutellaria baicalensis Georgi has already been demonstrated, little is known about its antibacterial activity against oral pathogens in vitro . Therefore, the aim of this study is to evaluate the antibacterial activity by six different kinds of Scutellaria baicalensis Georgi extracts in vitro . The three kinds of bacterial strains were used as follows: Streptococcus mutans ATCC 25175, Streptococcus sobrinus ATCC 33478 and Streptococcus salivarius ATCC 7073. The antibacterial activity was determined by the agar diffusion method, and the zones of growth inhibition were measured. The MICs and MBCs were determined by the broth dilution and agar dilution methods. The bactericidal activity was determined by time-kill assay. In all the Scutellaria baicalensis Georgi solvent extracts, except for water and ethyl acetate, a significant inhibitory activity was observed. The acetone and 80% ethanol, and the ethanolic extracts showed higher activity than the methanol extracts and produced inhibition zones ranging from 7.11±0.18 to 14.79±1.02mm in diameter at a concentration of 750μg/disk. The MIC value of the Scutellaria baicalensis Georgi extracts ranged from 125 to 1,000μg/m l . The MBC values for different strains and extracts ranged from 250 to 2,000μg/m l . Thus, Scutellaria baicalensis Georgi would be useful for the suppression of oral pathogens, and has the potential for use in the prevention of dental caries.

Comparison of the hand disinfectant effects between super hypochlorous water and 7.5% povidone-iodine

The objective of this study was to compare the hand disinfectant effects between super hypochlorous water and 7.5% povidone-iodine. Subjects included thirty pediatric dentists. They first watched the educational videotape for hand disinfection. They then pressed their right five fingers on Brain Heart Infusion (BHI) agars. They disinfected their hands under running super hypochlorous water until they considered to be enough clean, removed the excess water using a paper towel and again pressed their fingers on the BHI agars. Furthermore, the individual disinfectant time was measured. The agars were incubated at 37°C for 48 h, the colonies counted and calculated as logarithmic values. The same procedures were performed using 75% povidone- iodine two months later. As results, the following observations were shown. The disinfectant effects of super hypochlorous water were significantly more effective than that of 7.5% povidone-iodine. There was no correlation between disinfectant effects of both disinfectants and the hand disinfecting times.

Caries-risk assessment in early childhood using a caries activity test

Abstract Background Caries-risk assessment based on the individual caries-risk is very important in the public health setting. The objective was to longitudinally assess the caries-risk of each group using cutoff points. Each groups were low, moderate, progressive border, improved border, moderately high, and high caries-risk groups which were determined based on the 18-month and 2-year-old current and 3.5-year-old predicted cutoff points. Methods This study was a two-year longitudinal study of 1,206 children born in 2000. The children were divided into six caries-risk groups using the current and 3.5-year-old predicted cutoff points at 18 months and 2 years of age. It was investigated as to which caries-risk assessment was better. Results The 3.5-year-old predicted cutoff points calculated based on the 18-month and 2-year-old caries activities were more suitable for caries-risk assessment through analysis of significant differences of the mean numbers of dft in each groups. Conclusion It was suggested that researchers and practitioners should try to keep caries-risk of children in the low or moderate caries-risk groups for caries prevention.

A longitudinal study of early childhood caries risk, dental caries, and life style

Abstract The objectives of this longitudinal study were to assess childrens caries risk and mean number of decayed teeth and determine their life style factors that influence their caries activity. A total of 283 children were selected based on the following criteria: they had 1.5, 2.5, and 3.5-year-old oral examinations, participated in Cariostat microbial sampling and the mother of a child filled out the questionnaires. Caries experiences of children were 2.1% for the 1.5-year-old, 8.1% for the 2.5-year-old, and 14.8% for 3.5-year-old period, respectively. Caries risk at the 1.5-year-old period showed significant differences ( P P

Influences of diet on caries activities and caries-risk grouping in children, and changes in parenting behavior

Abstract Background Dental caries incidence in early childhood is known to influenced by the behavior of parent with their children, and clinicians and dental staff are advised to provide parents with effective oral health instructions. The objectives of this study were to identify the influence of diet of 18- and 24-month-old children on caries activities and investigate changes related to the behavior of their parents after receiving health instructions regarding caries risk for 2-year-old children. Methods The subjects were 1,206 child-parent pairs. The children participated in 18-, 24-, and 42-month-old health examinations at Kurashiki City Public Health Center in Kurashiki City, Japan. Cariostat, a caries activity test (Dentsply-Sankin Co., Tokyo), was conducted and the children were then classified into 6 caries-risk groups based on the 42-month-old predictive cutoff points. Their parents were given oral health instructions on caries prevention by dental hygienists of the Kurashiki City Public Health Center. In addition, a questionnaire regarding diet was given to identify its influence on caries activities in 18- and 24-month-old caries activities in 18- and 24-month-old children, as well as the influence of changes in parenting behavior. Results A significant number of children in the high-risk group received breast feeding or bottle-feeding with liquids other than water at 18 months of age. Also total time for sucrosecontaining food intake was significantly associated with increased caries activity at 18 months of age. After giving oral health instructions to parents of the 18-month-old children dietary habits significantly correlated with the high-risk group at 24 months of age were breast feeding or bottle-feeding with liquid other than water, total intake time of sucrose-containing food, and frequency of sucrose-containing foods intake. Furthermore, parents whose children were in the higher caries-risk group at 18 months of age showed a lower level of change in parenting behavior as compared to those with children in the lower caries-risk group. Conclusion It is important to assess problematic dietary habits in accordance with caries-risk in young children and change parent behavior through effective oral health instructions. Clinical Implication Clinicians can identify problematic dietary habits in children based on caries-risk and provide effective oral health instructions to parents, which may influence.

Inhibition of the adhesive ability of Streptococcus mutans on hydroxyapatite pellet using a toothbrush equipped with TiO2 semiconductor and solar panel

Abstract TiO 2 has an antibacterial effect against Streptococcus mutans ( S. mutans ). The objective of this study was to show the Inhibition of the adhesive ability of S. mutans on hydroxyapatite pellet using a toothbrush equipped with TiO 2 semiconductor and solar panel. Gradual brushing of 9 hydroxyapatite pellets was done by the same person using a solar toothbrush under 750/LUX light source in water. As a control, pellets brushed with a placebo toothbrush were done using the same procedure by the same person. All the pellets were inoculated in 10m l Brain Heart Infusion (BHI) broth containing 100μ l of 10 8 CFU/m l S. mutans and 1% sucrose and then incubated at 37°C for 12 hours. After incubation, the adherence conditions of S. mutans on each pellet were checked. The bacterial count of S. mutans on the brushed pellets using solar toothbrush were fewer than those using placebo toothbrush. The quantities of adherence of S. mutans decreased according to number of brushing and adhesion on pellets brushed more than 50 times could not be recognized. However, adhesion of S. mutans on the pellets brushed using placebo toothbrush were recognized and the adhesive quantities were visually the same. These results occurred because of some electronic charges on the brushed pellets using solar toothbrush. Soladey-3 toothbrush prevented S. mutans adhesion to the hydroxyapatite pellet under a light source.

Microbial screening of Cariostat®-inoculated plaque samples from low and high caries risk children

Abstract The aim of the present study was to investigate caries activity and its association with the presence of S. mutans and S. sobrinus . The subjects were 499 children aged 2.5 years old, who participated in dental health examinations held from May 2006 to January 2007 at a health center in Katano City, Osaka, Japan. A dental examination was performed based on caries diagnostic criteria of the Health Policy Bureau, Ministry of Welfare, Japan. Plaque samples were collected using a sterile cotton swab from the maxillary buccocervical surfaces by the same dental hygienist. Two hundred seventy two (54.5%) children who had Cariostat score below 1.5 were determined as low risk and 227 (45.5%) who had a score above 2.0 as high risk. For microbial screening, 100 children were randomly selected from the high and low risk groups. The presence of S. mutans and S. sobrinus were detected using PCR technique. Thirty seven (18.5%) children had S. mutans alone, 20 (10.0%) had S. sobrinus alone, 16 (8.0%) had both S. mutans and S. sobrinus , and 127 (63.5%) had neither S. mutans nor S. sobrinus . Cariogenic bacteria were detected more from high caries risk than low caries risk children. A larger number of S. sobrinus was found in children with high df numbers than low df numbers. In this study, it was shown that S. sobrinus was more closely related with high caries risk activity and high df numbers.

In vitro antibacterial effects of the crude extracts of Sophora alopecuroides against oral microorganisms

Sophora alopecuroides is widely used in Mongolian traditional medicine. The antimicrobial effects of the methanolic and aqueous extracts of its roots against Streptococcus mutans, Streptococcus sobrinus and Staphylococcus aureus were examined in vitro. Four fractions were obtained from methanol extract and labeled as Fractions-1, 2, 3, and 4. The MICs and MBCs of the crude extracts of Sophora alopecuroides were determined, and bacterial cell growth curves in the presence of Fractions-1, 3, and 4 were drawn. Among the methanolic extracts, the extracts of Fractions-1, 3, and 4 possessed strong inhibitory effect on the growth of mutans streptococci and S. aureus. Fraction-2 and the aqueous extracts of S. alopecuroides had weak antibacterial activities. Thus, S. alopecuroides would be useful for the suppression of oral pathogens, and has potential for use in the prevention of dental caries and treatment of diseases caused by S. aureus.