For decades, dental
implants have offered alternatives to dentures and bridges, improving
people's lives by giving them replacement teeth that look a bit more
natural. But, despite the advances in prosthetic teeth, not everybody
is smiling: placing the implants can be a complicated, expensive and
lengthy process of trial and error for both the dentist and the patient.
And, the results aren't always aesthetically pleasing.
Fortunately, Atlantis Components Inc. (Cambridge, Mass.), a custom dental
products company, has begun to change the often-bleak scenario of "false
teeth." The company has enabled approximately 1,000 dentists around
the country to provide implants that look as natural as real teeth in
less time and at a lower cost. A key part of Atlantis' process relies
on digital duplication technology from Raindrop Geomagic (www.geomagic.com).
From Frustration to Innovation
A dental implant has three main parts: the fixture, which anchors
the implant to the jawbone; the crown, which replaces the natural tooth;
and the abutment, the part that screws into the fixture and holds the
crown in place. Perhaps the most difficult stage of the procedure is
fitting the abutment.
"It can be very time-consuming to fit an abutment," says Tom
Cole, Atlantis president. "For one thing, the mouth is a difficult
place in which to work. And, depending on when the tooth was extracted
or lost, there can be difficulties with the quality of bone in which
to place the fixture."
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 |
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| Step
1 - The Fixture |
Step
2 - The Abutment |
Step
3 -The Finished Crown |
Because much of
the bone might have shrunk over time, dentists often must angle the
fixture in a patient's mouth to anchor it into solid bone. These angles
create problems in making the abutment conform to the natural shape
of the patient's other teeth. Abutments also can be difficult to seat
on the implant the later in the process they are placed, resulting in
entrapment of the gums before the crown can be put into place. Once
the abutment is placed, numerous radiographs can be required to ensure
that it is properly seated, resulting in more time and expense.
Frustrated with existing tooth implant-abutment methods, Dr. Julian
Osorio, a Boston prosthodontist, formulated
an abutment concept that would fit the exact geometry of the patient's
mouth. His goal was to create a process that would make implants accessible
to mainstream dentistry. Osorio founded Atlantis Components in 1996,
with a product that has changed implant dentistry The Atlantis Permanent
Healing Abutment.
Building a Better Abutment
To create his product, Dr. Osorio turned to the world of CAD/CAM technology
and Geomagic Studio, which makes it possible to take output from 3D
scanners and digitally duplicate the shape, textures and color of real-world
objects, including the cast of a patient's mouth. Geomagic Studio models
can be output directly to CAD software, stereolithography devices or
CNC manufacturing systems. They can also be automatically transformed
to highly detailed, but very small, models that can be displayed efficiently
on the web.
"Raindrop Geomagic allows us to obtain an accurate visualization
of the cast of the mouth in the computer. This is very important in
ensuring that the abutment has the proper fit," says Cole, who
is not only president, but an engineer who helped develop the Atlantis
abutment process. "We're the first company to really make this
process easy by taking advantage of computers and dental knowledge to
design the abutment using the patient's individual oral geometry."
The Atlantis process begins with scanning a cast of the patient's mouth
provided by the dentist. Geomagic Studio 3.0 is used to create surfaces
from the scanned point cloud data. The surfaces are then imported into
CAD software.
"The surface of the teeth is used as reference geometry for accurate
modeling of our abutment. Surfacing the dental anatomy in Geomagic Studio
allows us to modify CAD models in context, thus accurately producing
an abutment that fits into the patient's mouth with no further adjustments,"
says Bethany Grant, Atlantis senior development engineer.
The template-based workflow feature of Studio 3.0 increases productivity
by enabling surface patch layouts to be re-used, eliminating the repetitive
task of creating new patch layouts for similar models.
"Exact Anatomic Duplicate"
Dr. Joseph Gian-Grasso, a Philadelphia dentist who has been in practice
since 1973, and has been placing implants since 1983, has used the Atlantis
abutment on about 50 patients in the last year or so. Dr. Gian-Grasso
estimates that the Atlantis process saves him between two to six months'
time because the impression for the abutment can be made the same day
the fixture is placed in the bone. Previously, Dr. Gian-Grasso had to
wait for the implant to be integrated with the bone.
"If you've got a busy practice, time is money," Gian-Grasso
says. "Most patients really want the process completed expeditiously
and expertly. The Atlantis abutment allows us to do that."
In the earlier days of implant dentistry, Gian-Grasso said the abutments
he used were more a one-size-fits-all, off-the-shelf type product. "In
an ideal circumstance you would have an acceptable result, but with
the Atlantis abutment, the result is much more predictable because it
is customized to the exact fit of the patient's mouth," he says.
"The abutment actually reproduces the exact anatomic duplicate
of what a dentist would try to make manually."
A Solution For Mainstream Dentistry
Using Raindrop Geomagic Studio 3.0 with CAD/CAM technology, what once
took 10 visits for the implant patient now only takes three to five
visits. Dr. Osorio's goal of bringing implant technology to mainstream
dentistry has become a reality, and the real winner is the patient,
who walks away with a new smile that looks completely natural in far
less time than ever before.