Periodontal Disease

[Drsumitra]

Objectives: To study whether the amount of dental
plaque, which indicates poor oral hygiene and is
potential source of oral infections, associates with
premature death from cancer.
Design: Prospective cohort study.
Participants: 1390 randomly selected healthy young
Swedes followed up from 1985 to 2009. All subjects
underwent oral clinical examination and answered
a questionnaire assessing background variables such
as socioeconomic status and smoking.
Outcome measures: Causes of death were recorded
from national statistics and classified according to the
WHO International Classification of Diseases. Unpaired
t test, c

tests and multiple logistic regressions were
used.
Results: Of the 1390 participants, 4.2% had died
during the follow-up. Women had died at a mean age
of 61.0 (62.6 SD) years and men at the age of 60.2
(62.9 SD) years. The amount of dental plaque
between those who had died versus survived was
statistically significant (p<0.001). In multiple logistic
regression analysis, dental plaque appeared to be
a significant independent predictor associated with
1.79 times the OR of death (p<0.05). Age
increased the risk with an OR of 1.98 (p<0.05) and
gender (men) with an OR of 1.91 (p<0.05). The
malignancies were more widely scattered in men, while
breast cancer was the most frequent cause of death in
women.
Conclusions: This study hypothesis was confirmed by
showing that poor oral hygiene, as reflected in the
amount of dental plaque, was associated with
increased cancer mortality.
INTRODUCTION
Dental plaque is a bacterial biofilm formed
on dental surfaces. It plays a role in the
aetiology of oral diseases such as caries and
periodontal disease but may also associate
with systemic health and diseases due to
direct or hematogenic spread of microorganisms with subsequent upregulation of
cytokines and inflammatory mediators.

The
dento-gingival region is a natural habitat for
a magnitude of oral bacteria. The average
total microscopic count of bacteria from the
dental plaque has been calculated to be up to
2.1310

/mg wet weight.

Paster et al

estimated that there are 415 species of nonspecific bacteria in the subgingival plaque,
while pyro-sequencing techniques analysing
dental plaque and saliva have shown that
even thousands of microbial species may
inhabit the oral cavity.

Carcinogenesis is a multi-step process in
which cells accumulate changes in their
genetic material giving rise to alterations
of function.

These metabolic cascades can
also be triggered byinfection and inflammation which, in fact, have been estimated to
play a role in 15%e20% of all malignancies.

Because oral infections, and periodontitis
in particular, are highly prevalent in populations, there has been interest in studyingthe eventual link between oral infections and the prevalence of cancer. Smoking is a common risk factor both
for periodontitis and in many types of malignancies;
thus, smoking needs always to be taken into account in
this context.

Our group published a study in 2007
showing that patients with periodontitis and missing
molars seem to be at increased risk for premature death
by life-threatening diseases, such as neoplasms and
diseases of the circulatory and digestive systems.
We have recently also published a study showing an
association between periodontal disease and breast
cancer, with an OR of 2.36.
The putative mechanisms
involved in the association have been further reviewed by
Meurman and Bascones-Martinez.
Considering these
observations, the hypothesis of the present study was that
dental plaque is associated with premature death in
cancer. A high amount of dental plaque indicates poor
oral hygiene and, subsequently, was thought to be
a surrogate for increased risk for dental infections.
These, in turn, by triggering systemic reactions were
thought to lead to malignant transformation in a variety
of tissues. The specific aim of this study was to investigate
the underlying causes of death in malignancies among
1390 randomly selected young Swedes who had been
clinically investigated and followed up from 1985 to
2009. The Swedish national hospital admission and
death registers were used to record cancer. Death from
cancer was considered the end point of the study.