by malernee » Tue Sep 13, 2005 7:12 pm
We present below a concerted effort at the utilization of
these approaches is evaluating the evidence in support
of the utilization of chewing sticks for the prevention of
periodontal disease in tropical countries.
4. Chewing Sticks and Oral Health in Tropical
Countries
The Year 2000 Consensus Report on Oral Hygiene by the
World Health Organization (WHO) presented
arguments in support of the use of chewing sticks to help
in the maintenance of oral hygiene in tropical countries.
Indeed, chewing sticks have been used for decades, if
not centuries, in tropical countries of Asia, Africa and the
Americas for dental cleaning purpose and for
preventive oral health17. Little systematic analysis of the
evidence has been done, however. The significance of
this particular body of literature stands in the strong
association between diabetes and the progression of
periodontal disease18. Poor general and oral hygiene and
preventive medicine in tropical countries may favor the
onset and progression of either diabetes and or oral and
periodontal disease.
It is possible and even probable that in many
economically deprived countries whose people are not
afforded the luxury of expensive medications and
medical advances, many diabetics suffer from an
uncontrolled state of their disease. These patients may
be more likely to suffer from oral and periodontal
disease that will likewise remain untreated. In these
areas of world, it would be advantageous to consider
low-cost preventive options to help diminish the
incidence and severity of oral and periodontal disease,
such as chewing sticks that are derived from
endogenous plants.
In many tropical countries in Asia, in Africa and in the
Americas, the use of certain plants as chewing sticks has
been a common practice for teeth cleaning for centuries.
Sticks are usually chewed at one end into a tuft, which is
then used in a brush-like manner to clean the teeth, while
others are simply chewed on. Among the most
commonly used chewing sticks is the Miswak, which is
harvested from the plant Salvadora persica. The value of
the Miswak and of the many other plant species currently
used as chewing sticks throughout the world was
originally believed to rest solely on their mechanical
cleansing action. Recent research suggests several
additional properties of chewing sticks, including
hemostatic, analgesic, antimicrobial, buffering, and antiplaque
forming activity.
We have engaged in a process of systematic examination
of the available research literature on the topic of chewing
sticks essentially by the approach outlined above. We
have examined this literature by means of the protocols
outlined above, or slight modifications thereof. The
research papers that were found to adhere to the stringent
guidelines imperative in research design are discussed
briefly below. Taken together, the research evidence on
chewing sticks supports a relationship between their use
and cleaning effectiveness, pocket depth, gingival
recession, plaque inhibition, and antibacterial activity.
One report describes the oral hygiene habits of Tanzanian
schoolchildren participating in an oral health educational
program, and who were studied by focusing on the
cleaning effectiveness of chewing sticks among habitual
users versus toothbrush users. The report provides
adequate details about the research design such that the
study is straightforwardly reproducible: 124 students
ranging in age from 10 to 13 years were selected to
participate in the study. Subjects were separated into four
groups: 2 experimental groups, one each for chewing
stick and toothbrush use, and 2 control groups also
consisting chewing stick users and toothbrush users.
Each experimental group received oral hygiene
education, while the control group did not. Each habitual
chewing stick user was randomly matched with a
toothbrush user of similar sex, age, and school. The study
conducted single blind oral examinations by one
examiner. Baseline measurements indicated chewing
stick users experienced statistically significant more
plaque, while their gingival condition was not statistically
significantly different from that of their matched
toothbrush counterparts. Three months into the study,
data analysis indicated that subjects in the experimental
groups exhibited a statistically significant reduction in
plaque, and a large, but not significantly significant
decrease in gingival bleeding in contrast to the control
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group. The degree of reduction in plaque scores between
chewing stick and toothbrush experimental groups was
comparable. Chewing stick users, however, continued
to have higher plaque scores in comparison to
toothbrush users three months into the research. Taken
together, the data suggest that, with proper education,
oral hygiene can be improved regardless of the cleaning
instrument (i.e., toothbrush vs. chewing stick) used.
Data do not suggest that chewing sticks are superior to,
or equal to toothbrushes since chewing sticks users
consistently showed higher levels of plaque. However,
chewing sticks, with proper oral health instruction, may
provide an inexpensive and reasonably effective
alternative in removing plaque and improving gingival
health, when the conventional toothbrushes are not
available19.
These observations were confirmed and expanded in a
related cross-sectional study that used 236 Saudi
Arabian subjects categorized into three groups: a
chewing stick group, a toothbrush group, and a group
who reportedly used both chewing sticks and
toothbrushes in combination. All participants were
examined by two examiners: one interviewed the
patients about their oral hygiene habits, the other
performed all clinical measurements. This approach
sought to reduce examiner bias. Upon clinical
examination, investigators assessed plaque levels,
gingival inflammation, pocket depths, attachment loss,
and gingival recession. Clinical procedures for the
examinations were clearly and thoroughly presented
such that intra-oral examinations and their appropriate
assessment would be adequately reproducible. From
the viewpoint of SESTA, data analysis was somewhat
disputable, since, for instance, measurements such as
the frequency distribution of plaque and the presence of
absence of bleeding on probing ought to have been
analyzed as categorical data, and not by the parametric
test of ANOVA. Nonetheless, valuable information on
pocket depth can still be extrapolated from this study,
and the data indicate that chewing stick users exhibit
greater pocket depths on mid-facial surfaces in
comparison to toothbrush users. Subjects who used
both chewing sticks in conjunction with toothbrushes
were reported to have deeper pocket depths than either
group. It is possible and even probable, as the
investigators suggest, that patients in this group used
the chewing sticks more frequently than the toothbrush,
and that improper or aggressive use of the chewing stick
may be responsible for this type of periodontal damage20.
In an attempt to understand the mechanisms by which
plant extracts may be beneficial to oral health, extracts
were studied for their ability to inhibit the growth or
physical properties of the bacteria suspected of
involvement in the initiation and progression of
destructive periodontal diseases. The extracts, from
plants commonly used in Kenya as chewing sticks, were
tested against three strains each of the proteolytic Gramnegative
organisms, Bacteriodes gingivalis and Bacteroides
intermedius and two strains of the anaerobic spirochaete
Treponema denticola. The source of plants used as chewing
sticks were obtained from a questionnaire distributed to
all primary schools in Kenya in which children were
asked to state what they used to clean their teeth and if
they used a chewing stick. At the end of a six-monthperiod,
over 11,400 responses were received, of which
over 70% claimed to use mswaki (i.e., Miswak). The
plants to be used for further study were identified by a
botanist from a pool of 284 different species and
narrowed down to the five most commonly reported
species. The effects of the plant extracts on bacterial
protease activity, measured by means of sound
biochemical protocols at five different concentrations,
generated data, which were appropriately analyszed
along SESTA criteria. Taken together, the findings suggest
that extracts from plants used in chewing sticks have the
property of interfering with the pattern of growth of
certain bacteria resident in the periodontal plaque flora,
as well as their proteolytic activity. The bacteria
identified to be most sensitive to these extracts were B.
intermedius, B. gingivalis and T. denticola. The findings
also indicated that, one of the plant species tested, C.
hisitanica, is a tropical species introduced in Kenya as a
plantation tree for timber and is widespread in regions
with a high economic potential, suggesting, this plant
species may present the possibility of widespread use as
chewing sticks into countries where these sticks are not
yet readily available21.
In conclusion, the evidence suggests that chewing sticks
are not superior to toothbrushes, although their use may
be beneficial, if moderate, when conventional tools for
oral health are not available. Evidence also supports the
effectiveness of chewing sticks as oral hygiene tools.
Therefore and based on their availability, low-cost, and
cultural acceptability, the research evidence supports the
use of chewing sticks as viable tools for preventive oral
hygiene.
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52
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Cross-cultural implications of evidence based dentistry
21. Homer KA, Manji F, Beighton D. Inhibition of protease
activitiesofperiodontopathic bacteria by extracts of plants
used in Kenya as chewing sticks (Mswaki). Arch Oral Biol
1990; 35:421-424.
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