Evening star., 1943-07-24
Studies Link Fast
Growth Of Teeth With
Decay Susceptibility
BY HOWARD w. BLAKESLEE,

Associated Press Science Editor.
CHICAGO.-Evide that teeth
are like babies, each one different
and that this may be worth remem-
bering in dental care, is coming to
light in studies at the University Of
Illinois College of Dentistry.
The Illinois findings show there
are different types of teeth that
go with different types of people
Not only that, but there are different
types in the same mouth. These
findings explain why promising dis
coveries about preventing tooth de-
cay have failed for so many people
people.
The studies are directed by DR..
Veikko Hurme, assistant professor
of operative dentistry He is a native
of Finland. reared in New England.
Certain Teeth More Vulnerable.
Tooth decay in most persons ap-
pears in rather fixed patterns. Hard
ly any one escapes cavities in the
first molarS, which are usually the
first permanent teeth. Upper front
teeth decay more frequently than
lower front. The lower front teeth,
or inclsors, usually are least SUBJ
ject to decay of all teeth.
The one widely-accepted cause of
decay, namely the acid-making
germs in the mouth, cannot explain
these patterns. The acid germs are
claimed to cause decay by working
in pits and crevices of teeth.
Whq, DR.. Hurme asked shoulc
the germs sit most often in the crew
ices of first molars? Why should
they choose relatively smooth-sur-
faced upper teeth in preference tc
lower front, which are about equally
smooth surfaced?
He started his study with the ori
gin of teeth, and the idea that il
would be surprising if they all grew
alike He found what seems to be a
new fact: That all teeth do not grow
at the same rate.
Rates Fit Decay Pattern.
The differences in growth rates
are quite large, a matter of many
months slower for some teeth than
for others. And these varying growth
rates appea: to fit the peculiar pat
| tern of dental decay.
1t appears the decay is greatest
in the teeth which grow fastest. The
first molars are the fastest-growing
of all, and most frequent for cavi-
ties. The upper front teeth grow
faster than the lower front incisors
The lower incisors are the sloWest
growing of all human teeth and
throughout life they are the most
durable
There is biological principle that
fastgroWing tissues are more liable
to damage than growing tissues
This appears to apply to human
teeth. There is visible evidence in
human teeth to support this idea
The rapid growing teeth otter
contain spots where the ename
looks different Sometimes the spots
are slightly dark, sometimes pure
white The spots are found less fire.
quently on the sloW-growing teeth
They seem to be defects in the
enamel. They do not always result
in decay. Up to the present no on,
has paid much attention to them.
Point Way for Solution.
| If other scientists confirm the
Illinois findings about fast-growine
teeth, there will be a better basi.
for applying the science of nutrition
to building sounder teeth
DR.. Hurme thinks there are struc-
tural differences between sets o1
teeth just as there are differences
in body build, chemistry and nutri-
tional needs If the different types
of teeth can be identified. dentists
will be able to handle the amount OF
grinding and the character of bridge
work differently for one type than
for another.
The Illinois studies suggest that
there will be fewer toothaches when
each tooth can be treated on the
basis that, like man, it has it's own
individual peculiarities. Dentists will
be not only tooth carpenters, but
diagnosticians.