In the South East Asia region, Piper betle L. (sireh)
are among the plants that have been associated with the
control of caries and periodontal diseases[1] and to the
control of bad breath[2]. Fathilah et al.
[3] have reported
that the crude aqueous extract of Piper betle L. leaves
exhibits antibacterial activity towards Streptococcus
mitis, Streptococcus sanguis and Actinomyces viscosus,
some of the early colonizers of dental plaque.
The microbial etiology of caries involves oral
pathogens and ecological shifts in dental plaque in
response to increased sugar challenge or decreased
salivary flow in the oral cavity[4]. The bacteria that are
most closely associated with caries development are the
mutans streptococci, which are known to possess high
acidogenic and aciduric properties, together with their
ability to synthesize extracellular glucans from sucrose
catalysed by GTFs. Their virulence is related directly to
their capacity to adhere and produce acids from
glycolysis in dental plaque at pH values of 4.0 or even
lower[5]. There are many ways of chemotherapeutic
avenues other than eliminating S. mutans selectively;
this includes reduction of glucan formation by GTFs
and reduction in the ability of the organism to produce
acids.
Most of the studies on plant extracts[6-9] have
demonstrated their antibacterial activities towards S.
mutans. The antibacterial activities may be attributed to
reduced growth, reduced adhering ability and reduced
glucosyl transferase activity. The adherence of the early
colonizers prepares the environment conducive for the
colonization of the secondary colonizers like Strep.
mutans[4]. Razak and Rahim[10] have reported that the
aqueous extract of Piper betle L. inhibits adherence of
early plaque settlers, which include Streptococcus mitis,
Streptococcus sanguinis and Actinomyces sp. to salivacoated
glass surfaces. In this way, extract of Piper betle
L. leaves indirectly inhibits the adherence of S. mutans
by making the environment not conducive for S. mutans
to adhere. The extract also exhibited potent inhibitory
properties against the growth of S. mutans and activity
of glucosyltransferase (GTF)[11]. The inhibition of
glucosyl transferase will affect the formation of glucan
which subsequently will make the environment less
conducive for the growth of S. mutans.