Page 249 - Inventions - A Visual Encyclopedia (DK - Smithsonian)

Colored X-ray
of teeth

Amalgam filling

Flexible arm for
Drill head moving the drill
FILLING IN THE HOLES
In the 1820s, several dentists, including Auguste Taveau
in France and Thomas Bell in the UK, started using a new
dental filling called amalgam. Made from silver and mercury,
it could be easily molded to fit a cavity in a tooth. In the IN GOOD HEALTH
20th century, more natural-looking white fillings made
of powdered glass, ceramic, and plastic were developed. REMOVING DECAY
Dental drills are mainly used
DENTAL BRACES for removing decayed parts of
The first wire braces for pulling teeth. They underwent a major
the teeth into position were made evolution from the mid-19th
by the French dentist Christophe- century onward, beginning
François Delabarre in 1819. Various with the introduction of the
improvements have been made clockwork drill in 1864, followed
since then, including the addition by the electric drill in 1875.
of elastic bands in the 1840s and the But these were surpassed by
development of dental adhesives in the compressed air-powered
the 1970s to keep the braces in place. turbine drill in 1949. Invented
Modern dental braces by the New Zealand dentist
John Patrick Walsh, its drill
head could spin at the rate
of 400,000 rpm (rotations per
minute)—compared to just
3,000 rpm for an electric drill.
WOW!

Rope and pulley system
Before the invention operates the drill head. ◀ SPEEDING IT UP
of amalgam fillings, Invented by the American dentist
dental fillings were made James Beall Morrison in 1871,
of hot, melted metal, the foot-powered “treadle” drill
which could be sped up dental treatment.
very painful. Adjustable
footrest
Foot pedal
is pushed up
and down to Treadle drill,
turn the drill.
1871

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