Kaname Nohno

Influence of dental occlusion on physical fitness decline in a healthy Japanese elderly population

The aim of this study was to clarify the relationship between dental occlusion and physical fitness by a longitudinal survey. A sample of 348 subjects (171 men and 177 women) aged 71 was investigated by Eichner index (EI) as an occlusal condition (Class A: no loss; Class B: partial loss; Class C: complete loss) and five types of physical fitness tests and were re-examined 8 years later. The upper 50% were sampled to analyze the correlation between each physical fitness decline and the EI at the baseline by logistic regression models. Logistic regression analyses revealed that leg extensor power (Class B vs. Class A; odds ratio=OR=4.61, p=0.010) and one-leg standing time with eyes open (Class C vs. Class A; OR=4.27, p=0.031) showed significant correlations with the EI at the baseline. In this study, partial or complete loss of occlusion was associated with a decline in leg extensor power or a decrease in one-leg standing time with eyes open. These findings suggest that maintenance of dental occlusion may prevent a decrease in activities of daily living in the elderly.

Fluoride Intake from Food and Liquid in Japanese Children Living in Two Areas with Different Fluoride Concentrations in the Water Supply

The purpose of this study was to estimate the average daily amount of fluoride from the diet ingested by Japanese children of ages susceptible to dental fluorosis in two areas with different fluoride concentrations in the water supply. Thirty-eight children aged 2–8 years participated in a survey of fluoride intake. Twenty-one out of 38 children lived in an area in which the community water fluoride concentration was an average of 0.555 ppm (moderate fluoride area: MFA), and 17 lived in a low fluoride area (LFA), which ranged between 0.040 and 0.131 ppm. To measure the fluoride intake, diets were collected with a duplicate-diet technique. The fluoride concentrations in each sample were measured using the diffusion technique of Taves and the electrode technique. Meanwhile, after clinical examinations for dental caries and fluorosis, 228 subjects aged 13–15 years were selected for analysis from the same communities. The mean DMFT in the MFA was significantly lower than that in the LFA. The severest grade of dental fluorosis observed was ‘very mild’ according to Dean’s fluorosis index in both areas. The total daily fluoride intakes were 0.0252–0.0254 mg F/kg/day in the MFA and 0.0126–0.0144 mg F/kg/day in the LFA. Differences in the fluoride concentration of drinking water in this study were reflected in the fluoride intake from the diet in a typical Japanese diet.

Association between volatile sulfur compounds and periodontal disease progression in elderly non-smokers.

BACKGROUND Periodontal pathogenic microorganisms produce volatile sulfur compounds (VSCs), such as hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. VSCs are toxic to periodontal tissue. Therefore, there is a relationship between periodontitis and the VSC level of mouth air. However, the association between VSC and periodontal disease progression has not been investigated in a longitudinal study. The purpose of this study is to evaluate the association between VSCs in mouth air and periodontal disease progression among elderly dentulous non-smokers. METHODS Two hundred forty-one dentulous non-smokers (103 males and 138 females; all 70 years old) had their VSC levels examined with a portable sulfide monitor, and their periodontal status was assessed. Periodontal examinations were performed at baseline and once a year for 3 years to investigate the clinical attachment levels of all teeth. Participants were classified by membership in tertile groups (lowest, middle, and highest) according to the value of baseline VSC measurements. RESULTS In negative binomial regression analysis, the number of teeth with periodontal disease progression for participants in the highest tertile of VSC measurement was greater (incidence rate ratio of 1.33, P = 0.011) than for the reference group (lowest tertile of VSC measurement) after simultaneously adjusting for sex, number of remaining teeth, and maximum clinical attachment level. CONCLUSIONS VSC measurements were significantly associated with periodontal disease progression in a non-smoking dentulous elderly population. This suggests that VSC measurements are useful for the diagnosis of periodontal disease progression.

Differential gene and protein expression of tissue inhibitors of metalloproteinases (TIMP)-3 and TIMP-4 in gingival tissues from drug induced gingival overgrowth

OBJECTIVES The purpose of this study was to analyse mRNA expression and protein localization of tissue inhibitors of metalloproteinases (TIMP)-3 and TIMP-4 in gingival tissues removed from drug (calcium-channel blocker) induced gingival overgrowth and periodontitis patients. DESIGN Employing RT-PCR, we evaluated TIMP-3 and TIMP-4 mRNA levels of 20 human gingival tissue samples taken from patients suffering gingival overgrowth (GO) and periodontitis (P). Then, using immunohistochemistry we investigated the TIMP-3 and TIMP-4 protein localization of five sample tissues from each group. RESULTS TIMP-4 mRNA levels in GO-gingiva tended to be lower than in P-gingiva but the results differed little (p = 0.22). Varying degrees of inflammation in the protein localization of TIMP-3 and TIMP-4 were found. TIMP-4 immunoreactivity (IR) was weak in the endothelial cells, fibroblasts, epithelial basal and parabasal cells while the degree of inflammation differed as well. TIMP-3 and TIMP-4 IR in inflammatory cells, including lymphocytes, plasma cells, and macrophages, were faint and intense respectively. For P-gingiva, both TIMP-3 and TIMP-4 IR expression was weak in the endothelial cells, fibroblasts, basal and parabasal epithelial layers. Expression of TIMP-3 was faint in the inflammatory cells, whereas TIMP-4 IR was strong. CONCLUSION Our findings suggest that TIMP-3 and TIMP-4 expression differs in GO and P-gingival tissues, both of which are potentially involved in pathogenesis.

Microbiological Effect of Essential Oils in Combination with Subgingival Ultrasonic Instrumentation and Mouth Rinsing in Chronic Periodontitis Patients

Thirty chronic periodontitis patients were randomly assigned to 3 groups: control, saline, and essential oil-containing antiseptic (EO). Subgingival plaque was collected from a total of 90 pockets across all subjects. Subsequently, subgingival ultrasonic instrumentation (SUI) was performed by using EO or saline as the irrigation agent. After continuous mouth rinsing at home with EO or saline for 7 days, subgingival plaques were sampled again. Periodontopathic bacteria were quantified using the modified Invader PLUS assay. The total bacterial count in shallow pockets (probing pocket depth (PPD) = 4-5 mm) was significantly reduced in both saline (P < 0.05) and EO groups (P < 0.01). The total bacterial count (P < 0.05) and Porphyromonas gingivalis (P < 0.01) and Tannerella forsythia (P < 0.05) count in deep pockets (PPD ≥6 mm) were significantly reduced only in the EO group. In comparisons of the change ratio relative to baseline value of total bacteria counts across categories, both the saline and EO groups for PPD 4-5 mm and the EO group for PPD 6 mm showed a significantly low ratio (P < 0.05). The adjunctive use of EO may be effective in reducing subgingival bacterial counts in both shallow and deep pockets. This trial is registered with UMIN Clinical Trials Registry UMIN000007484.

Tablets containing a cysteine protease, actinidine, reduce oral malodor: a crossover study

Tongue coating (TC) mainly consists of protein mostly from exfoliated epithelial cells. Until now, to reduce TC accumulation, only mechanical measures have been available, and the procedure involves unpleasant side effects, such as gagging reflex or carcinogenesis related to mechanical stimulation. We expected that protease might be effective in reducing the accumulation of TC causing oral malodor. The purpose of this study was to determine the effect of long-term use of candy tablets containing protease, actinidine, on both TC accumulation and concentration of volatile sulfur compounds (VSCs) in mouth air. We employed 14 subjects aged 24 to 54 years old for this study, and conducted a double-blind randomized crossover trial. The subjects sucked the tablets containing actinidine three times a day until the sixth day after starting the study. The tablets without actinidine were utilized as a placebo. Measurements of VSC concentration and TC accumulation were carried out before and after chewing tablets on the first day, and also on the seventh day. The levels of VSC and TC significantly (p < 0.05) decreased after tablets were taken on the first day in both the test and placebo groups. There was a statistically significant decrease (p < 0.05) in VSC after seven days of use only in the test group. The results of the study suggest that the tablets containing actinidine had an accumulative effect in reducing VSC in mouth air with long-term use.

Fluoride Intake of Japanese Infants from Infant Milk Formula

This study aimed to measure the fluoride (F) content of all infant milk formulas (IMF) available for purchase in Japan and estimate the F exposure of infants whose primary source of nutrition is IMF when reconstituted with different F concentrations of water. Twenty-two commercially available IMFs were purchased from 6 manufacturers in Japan. These IMFs included 21 milk-based products and 1 soy-based product. Each IMF was reconstituted using distilled water and 0.13 µg F/ml fluoridated water according to the manufacturers’ instructions. The F concentrations in each sample were measured using the hexamethyldisiloxane diffusion technique and an F ion-selective electrode. The mean F concentration of all products was 0.41 (range 0.15–1.24) µg/g. There were no statistically significant differences among mean F concentrations of newborn milks, follow-on milks and other milks or among manufacturers. The mean F concentration of all products, when reconstituted with distilled water and 0.13 µg F/ml water, was 0.09 and 0.18 µg/ml, respectively. The mean F intake from IMF ranged from 0.039 to 0.134 mg/day with distilled water and from 0.078 to 0.258 mg/day with 0.13 µg/ml fluoridated water, respectively. These results suggested that F intake of infants from IMFs depended on the F concentration of added water, and therefore the risk of dental fluorosis for most Japanese infants would be small since most Japanese municipal water supplies are low in F. However, there was a possibility to exceed the tolerable upper intake level, even under the limit of the law, especially for infants within the first 5 months of life.

Factors associated with mucosal dryness in multiple regions and skin: A web-based study in women

We hypothesized that feeling mucosal dryness in one body region and the skin may be associated with dryness in other regions and that there are common background factors for dryness. In an earlier web‐based survey, we reported prevalence figures of dry eyes, nose, mouth, skin, and vagina. In the present study, additional analyses were made to investigate the factors associated with dryness in each region, and simultaneous dryness in multiple regions.

Expression of neprilysin in periodontitis-affected gingival tissues

OBJECTIVE Although the pathogeneses of Alzheimers disease (AD) and periodontal diseases have overlapping features, including ageing and chronic inflammation, the association between AD and periodontitis remains unclear. To explore the pathogenesis of periodontitis, a comprehensive gene expression/transcriptome analysis in periodontitis-affected gingival tissues found that the AD pathway was significantly up-regulated in periodontitis-affected gingival tissues. AD-related genes, amyloid beta precursor protein (APP), interleukin-1 beta and compliment 1QA, were significantly elevated in periodontitis. In the present study, balance between mRNA expression of APP and a potent amyloid degradation enzyme, neprilysin (NEP), as well as protein localisation of APP and NEP were analysed. DESIGN Eighteen periodontitis-affected and 18 clinically healthy control gingival tissues were taken from patients with severe chronic periodontitis or undergoing tooth extraction. Total RNA was purified and used for quantitative reverse transcription real-time polymerase chain reaction (qRT-PCR). The localisation of APP and NEP was analysed by immunohistochemistry (IHC). RESULTS Both APP and NEP genes were up-regulated in periodontitis-affected gingival tissues. APP-expressing macrophages and NEP-expressing neutrophils and fibroblasts, reflecting inflammatory stages, were detected in inflamed gingival tissues by IHC. CONCLUSION The up-regulation of APP and NEP mRNA levels in periodontitis-affected gingival tissues compared with healthy controls was confirmed by qRT-PCR analyses. Since NEP is one of the primary enzymes that degrades amyloid beta, increased NEP mRNA levels in periodontitis may act as an inhibitor of amyloid beta accumulation in gingival tissues, balancing increased APP mRNA expression. However, NEP has several effects including degradation of vasoactive substances; therefore, further sresearch is needed.

A Comparable Study of Combinational Regenerative Therapies Comprising Enamel Matrix Derivative plus Deproteinized Bovine Bone Mineral with or without Collagen Membrane in Periodontitis Patients with Intrabony Defects

Aim: The aim of the present study was to examine the effectiveness of collagen membrane (CM) in regenerative therapy with deproteinized bovine bone mineral (DBBM) and enamel matrix derivative (EMD) for periodontal intrabony defects. Methods: Eighteen periodontal intrabony defects of nine chronic periodontitis patients were evaluated. Two defects per patient with probing pocket depth (PPD) ≥ 6 mm were assigned to two different types of treatments: EMD + DBBM + CM or EMD + DBBM. Clinical parameters including Gingival Index (GI), PPD, clinical attachment level (CAL), gingival recession (GR), bleeding on probing (BOP), tooth mobility (MOB), and the filled bone volume/rate (FBV/FBR), which was measured by cone beam computed tomography, were compared at baseline and 12 months post-treatment. Differences between groups were determined by the chisquare test, McNemar’s test, and Wilcoxon signed-rank test. Results: Clinically, PPD, CAL, and FBR significantly improved in both groups (p < 0.05). The between-group comparison showed that the EMD + DBBM + CM group resulted in slightly greater PPD reduction, CAL gain, and FBR; however, these differences were not statistically significant. Conclusion: Periodontal regenerative therapies comprising EMD and DBBM with and without CM resulted in positive clinical outcomes. The use of CM may result in better outcomes in MOB decrease; however, long-term prognosis must be further studied.