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Halitosis Oral Malodor
by Professor John Greenman.
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Direction of talk.
I'm going to cover the background
and early work,
and the measurement
of oral malodor.
The role of microbes
and tongue biofilm in malodor,
whether or not
there's a periodontal contribution
to oral malodor,
and the various interventions
that people can do
to try and reduce or ameliorate
the problems of malodor.
So we start with the background
and early work.
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Early work on breath malodor
was work done by Tonzetich
in the 1970s,
where he used gas chromatography
to analyze the sulphur compounds
in the mouth air of humans.
He also looked specifically
at the production
and origin of oral malodor
and reviewed the mechanisms
and methods of analysis,
he found that hydrogen sulfide,
methyl sulfide,
and dimethyl sulfide
were the most important gases,
and also showed
that the tongue surface
might be the most important site
of generation within the mouth.
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Early work also consisted
of something called
a salivary putrefactions model.
This is where work is mixed,
organisms that they had isolated
or indeed mixed cultures
of organisms from a mouth
and put them into media contenting
certain types of amino acids.
And Tonzetich, and McNamara,
and Kleinberg, and Codipilly,
these were the workers
who showed that anaerobes,
particularly
gram-negative anaerobes,
produced a higher degree of malodor
in culture than other groups.
They're also able to show that
some of the substrates
were very effective
in inducing odor
such as cystine or cysteine,
which the microbes change
to hydrogen sulfide.
Methionine, which microbes
change to methylmercaptan.
Ormithine, arginine or lysine,
which were changed to either
putrescine or cadaverine,
and tryptophan
that was changed to indole.
And, of course, all these gases
are highly aromatic,
highly smelly.
