relationship between chewing ability and high-level functional capacity in an 80-year-old population...

Or ig ina l a r t i c l e

Relationship between chewing ability and high-level functionalcapacity in an 80-year-old population in Japan

Yutaka Takata1, Toshihiro Ansai2, Inho Soh2, Sumio Akifusa2, Kazuo Sonoki1, KiyoshiFujisawa1, Akihiro Yoshida2, Shuntaro Kagiyama1, Tomoko Hamasaki2, Ikuo Nakamichi1,

Shuji Awano2, Takehiro Torisu1 and Tadamichi Takehara2

Divisions of 1General Internal Medicine; and 2Community Oral Health Science, Department of Health Promotion, Kyushu Dental College,

Kitakyushu, Japan

doi:10.1111/j.1741-2358.2007.00203.x

Relationship between chewing ability and high-level functional capacity in an 80-year-old populationin Japan

Objectives: To evaluate the association between high-level functional capacity and chewing in a middle-

old community-based population.

Background: Although basic and instrumental activities of daily living are known to be associated with

chewing ability in the elderly, an association between higher levels of competence and chewing ability has

not been evaluated in the elderly.

Materials and methods: The association between chewing ability using a number of different foods and

high-level functional capacity by the Tokyo Metropolitan Institute of Gerontology was evaluated in 694,

80-year-old people residing in Fukuoka Prefecture, Japan.

Results: A significant correlation was found, using multiple regression or logistic regression analyses

adjusted for various confounding factors, between the number of total chewable foods, hard foods or

moderately hard foods, and total functional capacity, instrumental activity, intellectual activity or social

role ability. In contrast, the number of slightly hard foods, easily chewable foods and remaining teeth were

only partly related to total functional capacity and intellectual activity.

Conclusion: High-level functional capacity including intellectual activity and social role in middle-old

elderly was associated with the ability to chew hard foods than to chew easily chewable foods. Mainte-

nance of chewing ability in elderly might result in better intellectual activity and social role.

Keywords: chewing, ADL, elderly, dental.

Accepted 13 September 2007

Introduction

It is well known that there is an association

between impaired chewing ability and malnutri-

tion. Impaired chewing ability may affect nutrient

intake1,2 and exacerbate nutritional status3,4. It is

also reported to be associated with general health

status among the elderly5–7. On the other hand,

masticatory ability for gummy jelly was reported to

be influenced by cognitive function in the elderly,

suggesting limitation using a test food8. Miura

et al.5 conducted a study on 79 elderly individuals

ranging in age between 65 and 74 years and found

that chewing ability was related to activities of daily

living (ADL) as determined by the Ministry of

Health and Welfare of Japan or the Tokyo Metro-

politan Institute of Gerontology (TMIG)9,10. Locker

et al.11 followed up community-dwelling old indi-

viduals aged 50 years and older for over 7 years,

and concluded that poor general health at baseline

increased the onset of a chewing problem. In a very

elderly Japanese population it was found that

chewing ability may contribute to independence in

ADL12. Physical fitness13 and quality of life (QOL)14

were also associated with chewing ability in the

very elderly and recently was found to be associ-

ated with mortality in community residents and a

possible predictor for their survival rate15.

� 2008 The Gerodontology Association and Blackwell Munksgaard Ltd, Gerodontology 2008; 25: 147–154 147

Although basic ADL, which includes feeding,

bathing, toileting and dressing, and instrumental

ADL, which includes shopping, preparing meals

and using transportation are known to be associ-

ated with chewing ability in the elderly, an asso-

ciation between higher levels of competence

(intellectual activity or social role activity) and

chewing ability has not been evaluated in a very

elderly population. Therefore, this study evaluated

the association between high-level ADL and

chewing in a middle-old community-based

population.

Materials and methods

In 1998, 1282 80-year-old individuals residing in

one of three cities (Buzen, Yukuhashi or Munak-

ata), four towns (Katsuyama, Tikujo, Toyotsu or

Kanda), one village (Shinyoshitomi), or one ward

(Tobata of Kikakyushu City) in Fukuoka Prefecture

of Japan were invited to participate in the present

study. Of these, 694 (54.1%) (276 male and 418

female) were included. The distribution of partici-

pants was 132 of 192 (68.8%) 80-year-old residents

in Buzen, 81 of 159 (50.9%) in Yukuhashi, 146 of

283 (51.6%) in Munakata, 24 of 42 (57.1%) in

Katsuyama, 42 of 67 (62.7%) in Tsuiki, 17 of 40

(42.5%) in Toyotsu, 58 of 116 (50.0%) in Kanda,

23 of 28 (82.1%) in Shinyoshitomi and 174 of 355

(49.0%) in Tobata. The authors performed a dental

examination on each subject in the manner rec-

ommended by the World Health Organization16.

The study was approved by the Human Investiga-

tions Committee of Kyushu Dental College, and

informed consent was obtained from all partici-

pants. The protocol was in accordance with the

Helsinki Declaration of 1975, as revised in 2000.

Questionnaires concerning food intake have

proved valuable in epidemiological surveys of

masticatory function in the elderly17–19. Accord-

ingly, each subject was asked about their ability to

chew the following 15 foods: peanuts, yellow

pickled radish, hard rice crackers, French bread,

beefsteak, octopus in vinegar, pickled shallots,

dried scallops, dried cuttlefish, squid sashimi,

konnyaku, a tubular roll of boiled fish paste, boiled

rice, tuna sashimi and grilled eel. These were se-

lected to represent four main groups: three foods

that are very hard to chew (hard rice crackers,

peanuts and yellow pickled radish), six foods that

are moderately hard to chew (French bread, beef-

steak, octopus in vinegar, pickled shallots, dried

scallops and dried cuttlefish), three foods that are

slightly hard to chew (konnyaku, a tubular roll of

boiled fish paste and squid sashimi) and three foods

that are easy to chew (boiled rice, tuna sashimi and

grilled eel)20. Japanese investigators21 compared

two methods, a chewing gum method and ques-

tionnaire, for examining masticatory ability, and

concluded that both tests were useful for evaluat-

ing chewing ability in epidemiological studies.

A questionnaire from 100 different food substances

was compared with the questionnaire in this study

for 15 in 110 full denture wearers, concluding that

the larger questionnaire is superior22. Nevertheless,

the shorter version has been widely used for sur-

veying the Japanese elderly population23. The

number of foods that a subject could chew was

used as an index of chewing ability. This was as-

sessed as a possible independent influence on the

high-level functional capacity as assessed by the

TMIG Index of Competence9,10, using multivariate

and logistic regression analyses.

The TMIG Index of Competence, a standardised

multidimensional 13-item instrument developed

by the TMIG group, was used to measure func-

tional capacity and in turn to measure the level of

competence corresponding to the fifth, sixth and

seventh sublevels of Lawton’s model24. The

13 items are shown in Table 1: items 1–5 were

Table 1 Tokyo Metropolitan Institute of Gerontology

Index of Competence.

Items

Instrumental

self-maintenance

1. Can you use public

transportation (the bus or

train) by yourself unaided?

2. Are you able to shop for

daily necessities?

3. Are you able to prepare meals

by yourself?

4. Are you able to arrange to

pay bills?

5. Can you handle your own

banking?

Intellectual

activity

6. Are you able to fill in forms

for your pension?

7. Do you read the newspaper?

8. Do you read books or

magazines?

9. Are you interested in news

stories or programmes dealing

with health?

Social roles 10. Do you visit friends’ homes?

11. Are you sometimes asked for

advice?

12. Are you able to visit sick

friends?

13. Do you sometimes initiate

conversations with young people?

� 2008 The Gerodontology Association and Blackwell Munksgaard Ltd, Gerodontology 2008; 25: 147–154

148 Y. Takata et al.

classified as instrumental self-maintenance, items

6–9 as intellectual activity, items 10–13 as social

roles and items 1–13 as total functional capacity.

The response to each item was simply ‘yes’ or ‘no’,

and was scored 1 for ‘yes’ or 0 for ‘no’. The total

score was the sum total of the number of items

answered ‘yes’, and a high score indicated high-

level functional capacity. A score for each subscale

of this index was also used to measure the capacity

levels of instrumental self-maintenance, intellec-

tual activity or social roles.

All data are reported as mean ± SD. Differences

in mean values between groups were assessed by

analysis of variance. When comparing between

groups, the chewable number of foods and number

of teeth were classified into four groups as shown

in Table 2. Categorical variables were compared

using the chi-squared test. Multiple regression

analysis was carried out to evaluate which factors

were related to high-level functional capacity after

adjustment for confounding variables. Logistic

regression was also used to determine which cate-

gorical factors were independent predictors of

functional capacity. All statistical analyses were

performed using StatView 5.0 (SAS Institute, Cary,

NC, USA). Results were considered statistically

significant when p < 0.05.

Results

The mean number of teeth was 8.0 ± 8.9 (n = 694),

and the number of foods that subjects could chew

was 11.6 ± 3.6 (n = 686). Of these individuals, 656

filled in questionnaires for the TMIG Index of

Competence. The mean scores of the TMIG index

were 10.9 ± 2.7 for total functional capacity

(maximum 13 points), 4.1 ± 1.3 for instrumental

self-maintenance (maximum 5 points), 3.1 ± 1.1

for intellectual activity (maximum 4 points) and

2.8 ± 1.2 for social roles (maximum points 4

points). A gender difference was present in the total

number of foods that were chewed, in the number

of foods very hard to chew and in those moderately

hard to chew, while no gender difference was

found in those slightly hard to chew and in those

easy to chew (Table 3). The number of teeth was

also different between men and women. However,

there was no gender difference in total functional

capacity, instrumental self-maintenance and social

roles, whilst a slight gender difference was found in

intellectual activity.

Associations of chewing ability or number of

teeth with high-level functional capacity were as-

sessed by simple regression analyses (Table 4).

Significant correlations were found in the total

Table 2 Groups according to

number of chewable foods and

number of teeth.

Group 1 Group 2 Group 3 Group 4

Total number of chewable foods 0–4 5–9 10–14 15

Number of foods very hard to chew 0 1 2 3

Number of foods moderately hard

to chew

0–1 2–3 4–5 6

Number of foods slightly hard

to chew

0 1 2 3

Number of foods easy to chew 0 1 2 3

Number of teeth 0 1–9 10–19 20‡

Table 3 Number of chewable foods,

number of teeth and Tokyo Metro-

politan Institute of Gerontology

Index of Competence in men and

women.

Men Women

Total number of chewable foods 12.1 ± 3.4 11.2 ± 3.6�

Number of foods very hard to chew 2.4 ± 0.9 2.1 ± 1.1�

Number of foods moderately hard to chew 4.1 ± 1.9 3.6 ± 2.1�

Number of foods slightly hard to chew 2.7 ± 0.7 2.6 ± 0.7

Number of foods easy to chew 2.9 ± 0.5 2.8 ± 0.5

Number of teeth 9.5 ± 9.6 7.0 ± 8.2�

Total functional capacity 9.9 ± 2.7 10.0 ± 2.5

Instrumental self-maintenance 4.1 ± 1.3 4.2 ± 1.3

Intellectual activity 3.2 ± 1.0 3.0 ± 1.1*

Social roles 2.7 ± 1.2 2.8 ± 1.1

*p < 0.05, �p < 0.01, �p < 0.001.


Chewing and high-level ADL in the elderly 149

number of foods chewed, the number of foods hard

to chew or those moderately hard to chew with

total functional activity, instrumental activity,

intellectual activity or social role activity. It was

also found that the number of teeth or number of

foods easy to chew was only slightly associated

with intellectual activity, but was not associated

with total functional activity, instrumental activity

or social role activity. In the number of foods

slightly hard to chew, a slight but significant asso-

ciation was found both with total functional

capacity and intellectual activity.

Total functional capacity and intellectual activity

were improved significantly in groups with an in-

creased number of total chewable foods, hardly

chewable foods or moderately hardly chewable

foods (Table 5). Instrumental activity also was im-

proved with increases in moderately hardly chew-

able foods, and intellectual activity improved with

increases in easily chewable foods. Intellectual

activity was increased with more remaining teeth

(v2=12.4, p < 0.01), but total functional capacity,

instrumental activity or social role was not different

among the four groups relating to number of teeth

(0, 1–9, 10–19, 20‡).

Multiple regression analysis adjusted for gender,

smoking, marital status and regular dental or

medical care showed that the total number of foods

to chew, number of foods hardly chewable or

number of foods moderately hardly chewable was

positively related to total functional capacity,

instrumental activity, intellectual activity or social

role activity (Table 6). The number of slightly hard

chewable foods, however, was only associated with

total functional capacity, and that of teeth or easy

chewable foods was only associated with intellec-

tual activity. Explanatory factors such as gender,

smoking, marital status and regular dental or

medical care on high-level ADL in regression

analysis was selected because there was gender

difference in the number of chewable foods and

ADL level. In addition, it is likely that marital status

and regular dental or medical care could be related

to dental care.

For logistic regression analysis, the subjects were

grouped according to the number of foods they

could chew (Table 7). Similar to the multiple

regression analysis, gender, smoking, marital status

and regular dental or medical care were adjusted as

confounding factors. Increases in total functional

capacity were 3.1 times or 3.4 times more prevalent

in individuals who were able to chew 10–14 or 15

foods than in those who were able to chew only 0–

4 foods. Similarly, total functional capacity was

improved in individuals who were able to chew a

higher number of hardly chewable foods or mod-

erately hardly chewable foods than in those who

were able to chew only few foods. Intellectual

activity was also improved in individuals who were

able to chew hard-to-chew foods or moderately

hard-to-chew foods, while social role activity was

only related to the number of hard-to-chew foods.

Improved total functional capacity was more pre-

valent in individuals with 1–9 remaining teeth than

in edentulous individuals (OR, 1.54; 95% CI, 1.02–

2.30; p £ 0.05), and the prevalence of improved

intellectual activity was higher in individuals with

20 and more teeth (OR, 1.91; 95% CI, 1.16–3.15;

p < 0.05) or 10–19 teeth (OR, 2.01, 95% CI, 1.28–

3.17; p < 0.01) than in edentate individuals.

Discussion

In the present study, a relationship was found be-

tween high-level functional capacity and chewing

ability in a community-based middle-old Japanese

population. The number of very hard and moder-

ately hard chewable foods was more closely asso-

ciated with high-level functional capacity rather

than that of slightly hardly and easily chewable

Table 4 Correlations between func-

tional ability and number of chew-

able foods or teeth, using simple

regression analysis in an 80-year-old

population. Coefficient of correlation

(r) is described.

Total

functional

capacity

Instrumental

activity

Intellectual

activity

Social

role

Total chewable foods 0.157§ 0.100* 0.159§ 0.099*

Hardly chewable foods 0.162§ 0.107� 0.133� 0.126�

Moderately hardly

chewable foods

0.153§ 0.096* 0.162§ 0.091*

Slightly hardly chewable

foods

0.086* 0.060 0.079* 0.055

Easily chewable foods 0.048 0.021 0.095* 0.002

Teeth 0.070 0.032 0.100* 0.032

*p < 0.05, �p < 0.01, �p < 0.001, §p < 0.0001.



foods. Intellectual activity and social role ability

were also more closely associated with the number

of chewable foods than instrumental activity.

A high level of competence using TMIG was

similarly reported to be associated with chewing

activity in 79 young-old (mean age 69.3 years)

subjects who were living in a Japanese Prefecture5,

and in 92 middle-old (mean age 80.5 years) sub-

jects who were residents in a nursing home for frail

elderly7. However, because of the small number of

Table 5 Prevalence of improved

high-level functional capacity among

four chewing groups in an 80-year-

old population, with the difference

being compared by chi-squared test.

Number of subjects who had im-

proved functional capacity/number

of all subjects, corresponding to the

number of chewable foods.

Total functional

capacity

Instrumental

activity

Intellectual

activity Social role

Number of total chewable foods

0–4 10/38 (26.3) 20/38 (52.6) 12/38 (31.6) 10/38 (26.3)

5–9 58/125 (46.4) 71/125 (56.8) 47/125 (37.6) 34/125 (27.2)

10–14 152/294 (51.7) 154/294 (52.4) 140/294 (47.6) 102/294 (34.7)

15 107/192 (55.7) 115/192 (59.9) 96/192 (50.0) 65/192 (33.9)

v2 12.0� 2.9 8.2 * 3.1

Number of hardly chewable foods

0 21/66 (31.8) 37/66 (56.1) 21/66 (31.8) 13/66 (19.7)

1 32/70 (45.7) 37/70 (52.9) 24/70 (34.3) 21/70 (30.0)

2 64/126 (50.8) 62/126 (49.2) 60/126 (47.6) 41/126 (32.5)

3 210/386 (54.4) 224/386 (58.0) 190/386 (49.2) 136/386 (35.2)

v2 12.2� 3.2 10.9* 6.4

Number of moderately hardly chewable foods

0–1 48/116 (41.4) 66/116 (56.9) 41/116 (35.3) 32/116 (27.6)

2–3 57/141 (40.4) 62/141 (44.0) 47/141 (33.3) 42/141 (29.8)

4–5 109/190 (57.4) 110/190 (57.9) 105/190 (55.3) 66/190 (34.7)

6 113/201 (56.2) 122/201 (60.7) 102/201 (50.7) 71/201 (35.3)

v2 15.8� 10.3* 22.8� 2.9

Number of slightly hardly chewable foods

0 5/15 (33.3) 10/15 (66.7) 8/15 (53.3) 7/15 (46.7)

1 14/38 (36.8) 17/38 (44.7) 14/38 (36.8) 10/38 (26.3)

2 45/99 (45.5) 51/99 (51.5) 38/99 (38.4) 28/99 (28.3)

3 263/496 (53.0) 282/496 (56.9) 235/496 (47.4) 166/496 (33.5)

v2 6.9 3.5 4.2 3.0

Number of easily chewable foods

0 2/3 (66.7) 2/3 (66.7) 2/3 (66.7) 2/3 (66.7)

1 5/19 (26.3) 5/19 (26.3) 5/19 (26.3) 7/19 (36.8)

2 23/52 (44.2) 32/52 (61.5) 15/52 (28.8) 13/52 (25.0)

3 297/574 (51.7) 321/574 (55.9) 273/574 (47.6) 189/574 (32.9)

v2 5.9 7.5 10.2* 3.1

Values in parenthesis are expressed in percentage.*p < 0.05, �p < 0.01, �p < 0.005.

Table 6 Relationship between func-

tional ability and number of chew-

able foods or teeth in an 80-year-old

population, as analysed by multiple

regression analysis, adjusted for gen-

der, smoking, marital status and

dental or medical care. Standardized

regression coefficient (b-value) is

described.

Total

functional

capacity

Instrumental

activity

Intellectual

activity

Social

role

Total chewable foods 0.162§ 0.106� 0.152§ 0.110�

Hardly chewable foods 0.171§ 0.116� 0.132� 0.137§

Moderately hardly

chewable foods

0.156§ 0.100* 0.155§ 0.100*

Slightly hardly chewable

foods

0.088* 0.064 0.068 0.065

Easily chewable foods 0.053 0.023 0.097* 0.006

Teeth 0073 0.036 0.091* 0.043

*p < 0.05, �p < 0.01, �p < 0.005, §p < 0.001.



subjects in these studies, the capacity levels of

instrumental self-maintenance, intellectual activity

or social roles were not evaluated separately in

association with chewing ability. Moreover, the

middle-old subjects7 were not a community-based

population, as in the present study. Therefore, our

findings first suggested that impairment of chewing

ability to chew hardly chewable foods may be re-

lated to a deterioration in high-level functional

capacity, intellectual activity and social role ability.

A similar association between chewing and

general health status was reported in elderly peo-

ple. Poor dentition status was related to deteriora-

tion in the systemic health of Japanese elderly

(mean age 79.7 years)25, with a relationship be-

tween cognitive function and mastication in Japa-

nese elderly females (mean age 82.3 years) who

were residents in the community or an institu-

tion26. Among nursing home residents, individuals

who were able to chew also had better cognitive

and functional capacity27 and this was related

to self-rated general health among elderly aged

between 65 and 79 years6. Poor general health

increased the onset of chewing problems in older

Canadians aged 50 years and older11 and impaired

chewing capacity was associated with the risk of

protein energy malnutrition in nursing home resi-

dents (mean age 84 years)3. Poor dental functional

status was associated with a lower daily fibre intake

in a group of older vegetarian Chinese women

living in an old age home1 and oral disorders had

an effect on the well-being and life satisfaction of a

population of medically compromised elderly peo-

ple (mean age 83 years)28. Social status29, social

resources30 or social class31 also influences the oral

and nutritional status. Together with our previous

findings that independency in ADL12, physical fit-

ness13, QOL14,32 and mortality15 were also associ-

ated with chewing ability in the very elderly, it

seems likely that chewing ability in elderly indi-

viduals may be widely related to their general

health condition. The present study also was in

agreement with these findings, and added new

understanding about this relationship; chewing

Table 7 Association between functional ability and number of chewable foods in an 80-year-old population, as

analysed by logistic regression analysis, adjusted for gender, smoking, marital status and dental or medical care. Odds

ratio (OR; compared with subjects able to chew only 0–4 foods) and 95% confidence interval (CI) are described.

Total functional capacity,

OR (95% CI)

Instrumental activity,

OR (95% CI)

Intellectual activity,

OR (95% CI)

Social role,

OR (95% CI)

Number of total chewable foods

0–4 1 1 1 1

5–9 2.22 (0.98–5.01) 1.11 (0.53–2.33) 1.35 (0.62–2.96) 0.95 (0.41–2.19)

10–14 3.11 (1.45–6.69)� 1.01 (0.51–2.02) 1.99 (0.96–4.13) 1.51 (0.70–3.25)

15 3.38 (1.54–7.44)� 1.36 (0.67–2.78) 2.12 (1.00–4.49) 1.39 (0.63–3.06)

Number of hardly chewable foods

0 1 1 1 1

1 1.74 (0.85–3.57) 0.82 (0.41–1.64) 1.11 (0.53–2.31) 1.92 (0.85–4.38)

2 2.40 (1.26–4.57)� 0.78 (0.42–1.44) 2.13 (1.12–4.04)* 2.23 (1.07–4.67)*

3 2.65 (1.49–4.72)� 1.12 (0.65–1.94) 2.09 (1.18–3.72)* 2.49 (1.27–4.87)�

Number of moderately hardly chewable foods

0–1 1 1 1 1

2–3 1.03 (0.61–1.73) 0.62 (0.37–1.04) 0.84 (0.49–1.44) 1.30 (0.74–2.27)

4–5 2.09 (1.28–3.40)� 1.08 (0.66–1.74) 2.25 (1.38–3.67)� 1.46 (0.86–2.48)

6 1.89 (1.16–3.05)* 1.22 (0.75–1.98) 1.80 (1.11–2.93)* 1.53 (0.91–2.58)

Number of slightly hardly chewable foods

0 1 1 1 1

1 1.13 (0.32–4.06) 0.39 (0.11–1.38) 0.57 (0.17–1.92) 0.36 (0.10–1.29)

2 1.62 (0.51–5.18) 0.46 (0.14–1.47) 0.60 (0.20–1.83) 0.43 (0.14–1.31)

3 2.25 (0.75–6.74) 0.64 (0.21–1.94) 0.80 (0.28–2.26) 0.54 (0.19–1.55)

Number of easily chewable foods

0 1 1 1 1

1 0.17 (0.01–2.40) 0.15 (0.01–2.09) 0.17 (0.01–2.46) 0.29 (0.02–3.98)

2 0.46 (0.04–5.38) 0.78 (0.07–9.31) 0.25 (0.02–2.94) 0.18 (0.02–2.19)

3 0.58 (0.05–6.44) 0.61 (0.05–6.79) 0.52 (0.05–5.80) 0.25 (0.02–2.82)

*p < 0.05, �p < 0.01, �p < 0.005.



ability to chew hardly chewable foods was more

closely associated with high-level functional

capacity, especially intellectual activity and social

role, than the ability to chew easily chewable foods.

Although the time span between the collection of

the data and our publication was considerably long,

the present findings could be considered worth-

while. Maintenance of chewing ability in the

elderly might contribute to better intellectual

activity and social roles.

In conclusion, high-level functional capacity,

including intellectual activity and social role in

middle-old elderly, had a greater association with

the ability to chew a larger number of hard chew-

able foods than with the ability to chew easily

chewable foods.

Acknowledgements

This work was supported in part by Grants-in-Aid

for Scientific Research (B) 18390570, 15390655

and by a Grant-in-Aid for Exploratory Research (C)

17659663 from the Japan Society for the Promo-

tion of Science.

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Correspondence to:

Yutaka Takata, Division of General Internal Medi-

cine, Kyushu Dental College, Manazuru 2-6-1,

Kokurakita-ku, Kitakyushu City 803-8580, Japan.

Tel.: +81 93 582 1131 (ext. 2011)

Fax: +81 93 582 0592

E-mail: [email protected]



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