A Reason to Convert from Glass to Plastic
The finest material for making glass eyes was in short supply
during WWII, since it had to be imported from Lauscha, Germany.
Fortunately, the plastics industry had already developed
a medical grade acrylic, (as reported by: Berens, C, Rothbard,
S. Synthetic plastic material for implantation following
enucleation. Am J Ophthalmol 1941;24:550).
The time was ripe for its application as a replacement for
the glass eye.
It was the Dental Corps, Army of the United States that
first reported and published a 'bulletin' (Erpf S. F., Dietz
V. H., Wortz M. S., et al. Prosthesis of the Eye
in Synthetic Resin, A Preliminary Report. The Bulletin
of the Army Medical Department, Vol. IV, No 1, July, 1945,
76-86.) on the fabrication of the impression moulded plastic
eye. Needless to say, it was the material of choice
when it became available to the public. The advantages
of plastic over glass were numerous. There was no longer
fear of breakage, it would not roughen with wear, and, if
it became chipped or scratched, it could easily be repaired
and polished. The curvature and thickness of the impression
moulded plastic prosthesis could adapt to the irregular configurations
of the orbital tissue, and atonal weaknesses in the eyelids.
It could improve cosmesis when there was orbital volume loss
that caused superior sulcus depression of the upper lid.
The moulded prosthesis could also be worn at bedtime, whereas,
the glass eye with its smooth concave posterior shape, that
allowed tears and secretions to accumulate behind it, had
to be removed nightly to give the socket tissues a rest,
and to prolong the life of the glass eye. (The glass
eye would roughen and discolor caused by tears and secretions.)