Color Reproduction of Teeth and Gums Images
Mutsuko Nichogi, Takehisa Tanaka, Osamu Yamada, and Katsuhiro Kanamori
Information & Network Research Lab., Matsushita Research Institute Tokyo, Inc., Kawasaki, 214-8501 Japan
SUMMARY
To obtain better informed consent from patients in
dentistry, the state of the disease and the treatment process
are effectively presented by images, and more realistic hard
copies are sought. In this research, we propose obtaining
realistic output images by the addition of rendering in the
CIE L
*
a
*
b
*
space to the conventional ICC Color Manage-
ment System framework. The image rendering processes
involve a process to expand and compress the chroma and
a process to enhance the contrast. To evaluate these proc-
esses, dentists performed subjective evaluation tests. We
found from the tests that the chroma required adjustments
particularly for a high degree of inflammation. The dentist
was able to select the processing in view of the test results
described above to match his diagnostic conditions and
produce hard copies after processing the images to convey
the patients condition in an easy-to-understand manner to
the patient, other dentists, and technicians. © 2001 Scripta
Technica, Syst Comp Jpn, 32(3): 2432, 2001
Key words: Color management; medical use; im-
age processing; color reproduction; printer.
1. Introduction
The patient has the right to obtain complete current
information concerning his diagnosis, treatment, and prog-
nosis in terms the patient can understand, according to this
declaration of the American Medical Association (1973).
This style of medical treatment is known as informed
consent.
The presentation of images of the teeth and gums is
an effective way to put informed consent into practice in
dentistry. For example, the patient can compare images of
the teeth and gums at the time of the initial diagnosis to
images as the treatment progresses, communicate with the
dentist, and confirm the state of his disease. In practice in
the United States, both the patients and the doctors often
save photos of the teeth and gums as the treatment pro-
gresses to prepare insurance claims and lawsuits about the
medical treatment. The importance of storing images of the
teeth and gums as electronic clinical charts, which has been
made possible by recent developments in electronics, view-
ing them on displays, and printing them as hard copies will
probably increase.
Accompanying the electronic production of these
kinds of images, this paper proposes an image processing
system for the teeth and gum images to make the patients
condition easy to understand with the objective of its use in
informed consent.
The proposed system is based on the Color Manage-
ment System (CMS) that accurately reproduces the images
on different imaging devices like displays and printers. One
CMS framework is suggested by the International Color
Consortium (ICC) standardization organization. The col-
orimetrically identical colors are reproduced on the output
device by transforming the input image based on the color
characteristics of the input device after being transformed
to the Device Independent Color (DIC) color space which
does not depend on the device. The proposed system pro-
duces images that convey the state of the teeth and gums in
an understandable manner by the two features of gamut
mapping which accounts for the color space of the image
© 2001 Scripta Technica
Systems and Computers in Japan, Vol. 32, No. 3, 2001
Translated from Denshi Joho Tsushin Gakkai Ronbunshi, Vol. J83-D-II, No. 1, January 2000, pp. 137144
This research is part of the R&D on Intelligent Imaging Technologies
of the Telecommunications Advancement Organization of Japan.
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