Biomedical Engineering Reference
In-Depth Information
pounded into a paste before being applied to the teeth. This evidence suggested that
the history of teeth cleaning in the ancient world could be traced back to several
thousand years ago.
After the Egyptians, the Greeks and the Romans improved the recipes for tooth-
paste by adding abrasives such as crushed bones and oyster shells, which were used
to rub away the particles that adhered to teeth. The powdered charcoal, powdered
bark, and more flavoring agents were mixed into toothpaste to improve one's breath.
Around A.D. 1000, the Persians wrote to advise their people to be wary of the dan-
gers of using hard abrasives as tooth powders. It was recommended that people used
burned hartshorn, the burned shells of snails, and burned gypsum. Other Persian
recipes involved dried animal parts, herbs, honey, and minerals. In addition, the
green copper salt verdigris, incense, honey, and powdered flintstone were also
recorded as tooth-strengthening agents [
109
].
In the eighteenth century, toothpowder, or dentifrice, became available in Britain.
These powders were developed by doctors, dentists, and chemists and included
substances that were very abrasive to teeth, such as brick dust, crushed china,
earthenware, and cuttlefish. Bicarbonate of soda was used as the basis for most
toothpowders, and some contained other ingredients that would not be considered
appropriate today, such as sugar. Borax powder was added at the end of the eighteenth
century to produce a favorable foaming effect. Glycerin was added early in the nine-
teenth century to make the powders into a paste and more palatable. Strontium was
introduced at that time as well, which serves to strengthen teeth and reduce sensitivity.
The main problem of toothpowder, which was improved by the twentieth century, was
the abrasive particles causing great damage to tooth enamel.
In 1873, toothpaste was first mass-produced. It was in a jar and it smelled good
for the first time. In 1892, Dr. Washington Sheffield was the first to put toothpaste
into a collapsible tube. Prior to World War II, toothpaste was packaged in small
lead/tin alloy tubes. The inside of the tube was coated with wax; however, it was
discovered that lead from the tubes leached into the product. It was the shortage of
lead and tin during World War II that led to the use of laminated (aluminum, paper,
and plastic combination) tubes [
110
]. The pure plastic tubes became common until
the end of the twentieth century. The breakthrough that transformed toothpaste into
the crucial weapon against tooth decay was the finding that fluoride could dramati-
cally reduce cavities. Dr. William Engler tested 400 preschool children and discov-
ered a dramatic reduction in dental cavities among children treated with fluoride
[
110
]. This study, along with many others done around the world, led to the wide-
spread introduction of fluoride in the 1950s.
1.7.2
Toothbrush
The toothbrush seems to have its origins in the chewing sticks of Babylonia as early
as 3500 B.C. Ancient Greek and Roman literature discusses the use of toothpicks,
which were used to keep the mouth clean. Over the years the toothpick evolved into
