Twenty-five years have passed since the CEREC system from
Sirona was in its initial developmental stages (Fig. 1). Many similar
ideas and devices have come and gone before and after
CEREC came onto the scene. Only one, other than CEREC,
has been successful enough to still be on the market, the E4D
Dentist Chairside CAD/CAM System from D4D Technologies
(Fig. 2). In the United States, Patterson has the sales and service
responsibility for the CEREC, and Henry Schein has the sales
and service responsibility for the E4D.
When the air turbine handpiece came into the profession in
the late 1950s, almost all restorative dentists purchased them
within a few years of their introduction. Similarly, when rootform
implants were proven, almost all oral surgeons and later
some periodontists, prosthodontists and general dentists implemented
them into practice. It appears that the in-office milling
concept is similar in its potential to facilitate restorative dentistry.
Why has it not had the same acceptance and growth as
It is estimated that about 12,000 in-office milling devices
have been sold to dentists in the U.S. from the two companies,
the major share of which are the CEREC, primarily due to their
head start. There are about 140,000 general dentists and
prosthodontists in the U.S., which indicates that less than 10
percent of the potential restorative dentists have chairside
CAD/CAM devices. Are all of those dentists using their
CERECs or E4Ds? That is impossible to determine. A few in-office
design and milling systems can be found for sale on the
Internet for unknown reasons. Some are older models of
CEREC that are probably being replaced with newer technology.
However, it has been our observation that a few dentists do
not find the concept compatible with their practices.
The frustrating fact to both of us is that we know from both
research and practice experience that the in-office CAD/CAM
concept works well, and that it can be financially feasible in a
busy restorative or prosthodontic practice. After significant
experience, the concept can be used for quadrants and even full arch
and implant restorations. Many studies have supported the
use of chairside design and milling systems. The references in
the following list contain articles supporting the concept and
show positive research on the devices.1-15 Implementation of the
system takes time, planning, teamwork, willingness and patience
The purpose of this article is to identify and discuss the
potential reasons that have impeded the in-office milling concept
from being incorporated into more practices and to make
suggestions for practitioners, distributors and manufacturers to
make the concept more desirable and useful for dentists.
CAD/CAM Negative Characteristics
and Needed Changes as Identified
The apparent negative points will be presented in the following
manner. Each concept will state the identified item followed by
potential solutions to that complaint.
Challenge – Cost
Currently, both systems and accessories require an initial
outlay of about $130,000. This amount is a significant impediment
for dentists, in spite of financing and the assurance that
increased revenue will come into their practices. Before the
recession, the initial cost was not as formidable as it has been
during the last two years, but numerous surveys have shown that
many dentists have refrained from such large capital expenditures
during the "great recession." Each of the companies selling
in-office milling systems requires a payment of about $2,600 per
month. Obviously, that payment is present in spite of the practitioner's
potential health challenges, vacations, a down economy
or a scarcity of patients. This amount is not much less than
the annual net revenue of a typical general dentist. However, the
dentist has greatly reduced laboratory fees, and the financial
needs can be met with an average amount of restorative treatment
in a typical practice.
Potential solution: Cost has been a major impediment for
many dentists. This is a challenge only solvable by the manufacturers
and the distributors of the devices. The companies have
put enormous amounts of money into developing CAD/CAM
technology for in-office milling. That investment must be recovered.
That goal has undoubtedly been accomplished by the original
device (CEREC), but time will probably be required for
the newcomer (E4D) to do so. Additionally, there is ongoing
research needed for each company to update and modify software
and hardware as the concept continues to evolve. The distributors
who sell and service the devices need to make a profit
also. Only the respective companies can know when it will be
possible to reduce the cost of the devices.
One potential for reduction is to put the same concept into
a simplified and less expensive delivery systems to lower cost,
which we will discuss later. However, it is well-known that, in
spite of relatively palatable lease payments, the overall investment
required to introduce this concept into practice causes
concern for most typical practitioners. The real solution to this
challenge appears to be to reduce the manufacturing cost of the
systems and pass those savings on to clinicians. Other similar
"expensive" technologies are experiencing rapid growth due to
decreased cost, such as diode lasers and cone beam CT imaging.
Challenge – Fear of the Unknown
In spite of some devout in-office milling users, key opinion
leaders and sales representatives assuring potential customers
about the usefulness of the concept, many dentists are fearful of
the unknown challenges they will face. There are numerous factors
contributing to that fear. Included are: anxiety about how
the concept will fit into their practices, the chance of unpredictable
ill health and lack of income, age and the thought of
retirement, the extreme debt (upward of $200,000) of young
graduates, the real possibility of further and prolonged economic
recession, various family challenges requiring more financial
resources, inability to determine the real increased revenue
that the concept will build into practice, and the knowledge that
the monthly payment continues in spite of the potential
Potential solution: If fear is an impediment for you, might
we suggest you meet with a user of in-office CAD/CAM to
observe a clinical demonstration and a testimonial of how this
concept is working in his or her practice? The Henry Schein or
Patterson dealers will be pleased to provide names of users for
you to contact and observe. When contacting these users ask
in-depth questions to determine if the concept will fit into
your practice environment. Distributors will often bring a system
into your office for a demonstration to allow you to see
how it works in your practice. In our observation, satisfaction
with the concept ranges from extremely positive acceptance to
dissatisfaction and selling the devices on the Internet. Only
you can see if this concept meets your needs and desires for
your specific practice.
Challenge – Negative Comments from Some Peers
The majority of in-office milling unit owners really like their
devices and enjoy having them in their practices. But some disgruntled
purchasers and non-users who are satisfied with their
conventional methods loudly proclaim that the concept did not
or will not fit their practice needs and that they will not use in-office
milling. These few negative practitioners often make
potential owners wary and afraid to purchase the devices.
Potential solution: Do you include all of the new technologies
or materials into your practice, and do you like all of the
concepts you have elected to put into your practice? Quite obviously,
you do not do so. Similarly, not all purchasers of in-office
CAD/CAM love their devices. Because they cost so much, their resentment is voiced more actively. As already suggested, please
connect with someone who had the concept fit well into their
practice. Take the time to see how they made the transition from
conventional dentistry to use of in-office design and milling systems.
Identify whether you have similar characteristics present
in your practice that ensure success with the concept, such as
high restorative need, competent computer ability, etc.
Challenge – The Relatively Small Number of
Purchasers to Date
Potential buyers become discouraged when looking at the
number of devices sold to date compared to the general population
of dentists… thinking that it would have sold better if it
were any good. However, the market penetration is quite good
when one considers that many practices with more than one
dentist have only one device, that the concept is expensive and
that it is relatively new technology.
Potential solution: This challenge has no real solution other
than to have all of the potential solutions stated in this article
implemented by manufacturers, distributors and practitioners.
The implementation of all of them would undoubtedly make
the concept more desirable to practitioners and lead to more
sales. It is well known that any new concept starts out as an
unknown and grows into a commonly used object. Examples are
automobiles, PCs, radios, TV, etc. The concepts must become
faster, easier, better and less expensive to become commonly
used. Additionally some dentists do not have interest in any
dental laboratory work and reject the concept on that basis.
Challenge – The Necessity to Change Long-stable
When a practice is organized, running smoothly and producing
adequate revenue, there is a tendency among some dentists
to reject anything that would decrease the stability of the
practice routine. Change is difficult, but change can be stimulating
and will bring a level of self-confidence and new enthusiasm
for dentistry. Incorporating in-office milling into a practice
usually involves educating dentists to delegate some of the procedure
to qualified staff members.
Potential solution: If this concept sounds interesting to you,
and you have investigated it thoroughly, changing your practice
routine will be exciting and refreshing to you. We have seen
mature practitioners who were relatively "burned out" with
practice become excited about dentistry again. Changing a practice
routine is a formidable thought until you determine that
you will "re-invent" yourself again. We do not mean to downplay
the needed organization and thought that must go into this
scheduling change. It will take some time to do so, but the result
will be satisfying to you and your staff.
Challenge – The Size of the Image-capturing Device
and the Milling Machine
As expressed to us from potential purchasers, there is some
frustration that both companies have large-wheeled, cart-type
devices that contain the necessary computer, the monitor, the
imaging handpiece, as well as other necessary devices. Many
offices, especially the older ones, do not have adequate space
to house the wheeled carts without compromising their
already crowded operatories. Additionally, significant space
must be found to locate the milling device, which is also very
large and heavy.
Potential solution: Their size can certainly be disagreeable
and obtrusive in small offices. There are too many large objects
already in treatment rooms. We have talked with the representatives
of the two companies about this challenge. In our opinion,
the large size problem must be overcome to make the concept
more acceptable to practitioners. Changing the cameras to smaller
sizes, changing the "cart" concept to a simple laptop or other
small package, and making the milling devices smaller and lighter
weight would greatly facilitate their acceptance into typical restorative/prosthodontic practices. However, the above suggestions
pose significant technical and manufacturing challenges.
Challenge – Lack of Desire to Delegate
Some dentists do not delegate many clinical procedures.
They do almost all of the clinical procedures themselves.
Average practices have two assistants. One of the best ways to
make the in-office milling concept financially acceptable is to
delegate a significant portion of the procedure to other qualified
staff persons. Such dentists must change their overall staff
delegation policies to facilitate more staff delegation or they
must raise their fees allowing them to spend a longer time
making the restorations.
A well-organized office in which staff delegation is accomplished
can make the in-office milling concept very effective and
efficient. A practitioner that rarely delegates must change his or
her delegation of procedures for optimum efficiency and acceptable
revenue production. Programs are available to train staff
persons to use the systems and to gain proficiency.
Potential solution: Do you delegate some or many clinical
responsibilities to staff? If so, the incorporation of in-office
milling will be a pleasure for you. If you do not delegate many
clinical tasks to staff, you will find a significant change in your
practice routine to have staff persons accomplish some of the in-office
digital impression procedures, design and milling. If you
elect to do all of the imaging and milling yourself, the concept
is not as financially acceptable as when you delegate much of the
imaging and milling tasks to staff, while you concentrate primarily
on tooth preparation and seating the restorations.
Delegating to dental assistants, dental hygienists or other staff
persons builds a sense of responsibility, self-esteem, trust and
teamwork. When they take on these new responsibilities they
appreciate your trust in them and they appreciate the opportunity
to expand their value to the practice.
Challenge – Relationship with Previous Dental
Some technicians and ceramists are concerned that the
dentist's total number of indirect restorations will no longer be
coming to the laboratory. But when laboratory technicians
and ceramists learn that only some of the indirect restorations
will be milled using an in-office milling device, and that some
of them might have data sent to the lab for milling, they are
Potential solution: Most dentists using in-office milling
make primarily posterior crowns and onlays. Some progress on
to more complicated and less frequently needed restorations.
Therefore, there is still need for laboratory technicians and this
will always be so. Additionally, some practices actually grow
the amount of both their conventional and CAD/CAM
restorative dentistry when incorporating CAD/CAM. Frankly,
as the concept continues to grow in popularity, the growth will
be slow and steady, not fast, thereby allowing your technicians
to accommodate the needed change. Many dentists become
more interested in the laboratory concepts in dentistry as they
use the devices.
Challenge – Concern about Quality and Longevity
In the U.S., most patients want and/or demand tooth-colored
restorations. Although many dentists favor metal restorations,
because of their proven longevity, these are not done with
the in-office milling devices currently in the U.S. Therefore,
dentists going into CAD/CAM milling in their offices feel compelled
to use tooth-colored ceramic or polymer restorations, the
most popular of which are currently the ceramic IPS e.max
CAD, lithium disilicate or VITA Mark II Blocs. This orientation
is uncomfortable for some dentists. Many worry about the
all-ceramic restorations produced by the in-office milling
machines regarding their quality and the amount of time they
Potential solution: Clinicians Report (previously CRA) staff
have been working with this concept for about 23 years. The
ceramic and polymer restorations made with in-office milling
have served in this time period as well as or better than laboratory
restorations made with similar materials. However, it is well
known and reported in the scientific literature that cast gold
alloy restorations have the longest service potential of all restorations.
You know well that very few patients want to display
metal in their mouths in spite of the known greater longevity to
be expected. In-office milled tooth-colored restorations placed
properly are serving very well.
Summary and Conclusions
It has been proven that in-office milling systems for dental
restorations are highly useful, functional and financially feasible
for many practices. The restorations made with the CEREC and
E4D devices are serving as well as or better than restorations
made by conventional laboratory procedures. There are numerous
reasons why these systems have not made more market penetration – which have been detailed and discussed above. It is
our hope that manufacturers, distributors and practitioners will
work together to find ways to further implement this technology
into the mainstream of restorative practice.
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