| Osteoporosis,
periodontitis and tooth loss are public health
concerns that affect significant numbers of
older men and women. Osteoporosis is a disease
characterized by low bone mass leading to an
increased susceptibility to fractures of the
hip, spine and wrist. Periodontitis is an
infection of the tissues surrounding and
supporting the teeth and is a common cause of
tooth loss. In the absence of a large body of
scientific knowledge, it is often assumed that
the systemic bone loss characteristic of
osteoporosis plays a role in the bone density of
the jaw and significant dental health concerns
such as periodontitis and tooth loss. However,
research in this area has been scarce.
Skeletal Bone Density and Tooth Loss
The alveolar process is the segment of the jaw
bone that accommodates the teeth. Loss of
alveolar bone has been associated with increased
tooth mobility and tooth loss in several
studies. For example, Taguchi and associates
found a positive correlation between decreased
mandibular bone density and tooth loss among
elderly women. It has been suggested that
systemic bone loss may contribute to tooth loss
due to increased resorption of alveolar bone. In
a 1996 study of 189 healthy postmenopausal
women, Krall, Garcia, Dawson-Hughes and
associates found that "normal" bone loss (1
percent per year) was significantly associated
with increased tooth loss. A study by the same
group two years earlier produced a similar
finding.
Given an apparent association
between skeletal bone loss and tooth loss, it
has been suggested that dental x-rays may in
fact serve as good screening tools for
osteoporosis. In a study published in 1996,
researchers at the University of Washington
School of Dentistry found dental x-rays to be a
highly effective method for distinguishing
patients with osteoporosis from patients with
normal bone density. A British study by Horner
and others concluded that mandibular bone
density measurements significantly correlated
with bone density measurements at other skeletal
sites. Additional studies should help clarify
any potential role for dental radiographs in the
detection of individuals with osteoporosis.
Periodontitis and Bone Health
It is estimated that periodontal disease affects
more than half of the United States population,
with 30% of older adults experiencing severe
forms of the disease. While tooth loss is a well
documented consequence of periodontitis, there
is less evidence demonstrating an association
between periodontitis and skeletal bone density.
In an arm of the National Health and Nutrition
Examination Survey III (NHANES), researchers at
the University of Buffalo led by Wactawski-Wende
found a strong and direct relationship between
bone loss, periodontitis and tooth loss. The
results of this study involving nearly 2600
women have yet to be published and were
announced earlier this year at the annual
meeting of the American Association for the
Advancement of Science.
The
Estrogen Connection
The role of estrogen in osteoporosis prevention
and treatment is well established. What is less
clear is the effect of estrogen on alveolar bone
density, tooth loss and periodontitis. One such
study by Payne and associates found that
estrogen deficient women had a greater loss in
alveolar bone density. It is possible that the
loss of alveolar bone mineral density leaves
bone more susceptible to periodontal bacteria,
increasing the risk for periodontitis and tooth
loss.
Replacement estrogen may help
minimize the occurrence of negative dental
outcomes in postmenopausal women. In an arm of
the Leisure World Study Paganini-Hill reported
that older women on estrogen replacement therapy
had lower rates of tooth loss than non-users.
Similar findings were reported last year by
Krall, Dawson-Hughes and associates who studied
nearly 500 elderly female participants in the
Framingham Heart Study. The authors found that
estrogen users retained a significantly higher
number of teeth than non-users and that duration
of estrogen use was positively correlated with
lower rates of tooth loss.
While additional research is
needed to clarify the relationship between
systemic and oral bone loss, investigators are
hopeful that efforts to optimize skeletal bone
density will have a favorable impact on dental
health. |
