n absolute conviction that traditional dental
management produced bottlenecks, wasted time, underused capacity, and created frustration for
dentists and patients.

In the two intervening years, Bahri s gut feeling that there had to be a better way had driven him
to study a shelf-full of management books about continuous improvement. He had come to the
conclusion that dental management schools, like their counterparts in business, had made some
fundamental misjudgments about the best ways to manage office work. One of the shared
misconceptions, Bahri believed, was the traditional view that batching -- grouping activities by
type -- was always the most efficient way of organizing work. Schools taught dentists to batch
similar procedures when treating patients to limit the time-consuming setup of instruments and
materials that are performed to switch from one dental procedure to another. Thus, if you need
two fillings and two crowns, your dentist schedules the fillings for one appointment and the
crowns for another. Batching avoids setups but, as
Lean Thinkers
know, usually leads to more
waste.

The traditional dental office also has a departmental wall between dentistry and hygiene.
Dentists and assistants treat patients in dedicated dental chairs; hygienists clean patients teeth in
dedicated hygiene chairs. Part of the reason for the distinction is due to tradition, part is due to
the time needed to perform the setups between procedures, and part is due to the hour that
normally is allocated per cleaning. As a result, patients move back and forth between
departments.

Scheduling their movements is the job of another department, the front desk. In the traditional
dental office it is the central point for collecting and distributing all information. This role turns
the desk into a bottleneck as patients arriving and leaving every hour schedule new
appointments, change existing appointments, make payments, and ask questions about insurance.
Desk staff also updates dental charts, answers inbound calls, and makes outbound reminder calls.
When Bahri was building his Jacksonville practice, the office stopped if his sole receptionist
called in sick. Some days I worked for free because I had no one to check out patients and take
payments, he recalled.

Looking for Alternatives
With traditional office management techniques everything seemed so out of control, he
concluded. But what could I do?

At the suggestion of a fellow doctor, who had applied some
total quality management
(TQM)
principles to manage a hospital emergency room, Bahri investigated applying TQM to dentistry.
I tried applying some of [W. Edwards]Deming s statistical process control principles to my
practice, but I didn t feel it was improving a lot so I kept studying and looking for books, said www.lean.org

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Bahri, who emigrated from Lebanon in 1990, where he was a founding director of the School of
Dentistry at the Lebanese University

By the mid-1990s, Bahri s bookshelf was a record of the era s quality fads with works by Philip
Crosby, Tom Peters, Michael Hammer, Steven Covey, Michael Gerber, Eliyahu Goldratt, and
Peter Senge. He dedicated time every Thursday to teach office staff TQM concepts and cross-
training. Dental assistants and hygienists learned front desk duties or how to answer common
questions about insurance. Front desk staff learned how to set up cubicles in between procedures.
His reading and cross-training resulted in some improvements to isolated processes but no
overall dramatic improvement in how the office ran. Then in 1993, his reading led him to
Masaaki Imai s Kaizen that described TQM as well as the

Toyota Production System
. The book
was a smooth transition between TQM and TPS, said Bahri.

As he implemented key
lean production concepts
in dentistry, he was struck by the importance of
continuous flow
while listening to a tape of
Lean Thinking

(Simon & Schuster, 1996).
I stopped
the tape and started thinking, That s what I needed, Bahri recalled. He read books by Taiichi
Ohno, Shigeo Shingo, and other Japanese authors, studying all the lean tools from
Five Ss
to
total productive maintenance. He was most impressed by the single minute exchange of die
concept for slashing setup times. I was very impressed by reducing setup time, he said. It was
the heart of establishing flow.

Dentistry as a Job Shop
Setups are almost as common and just as wasteful in the average dentist s office as in the
average factory. Just as a factory stops a process to set up or change tools and materials when
switching between different jobs, dentists stop to change instruments and materials when going
from one procedure, such as a filling, to a different one, such as a root canal.

In manufacturing, mass production thinking told managers to schedule work in large batches to
make up for the time lost when equipment was stopped for setups, which could take hours. The
problem from a lean thinking perspective was that large batches led to a host of wastes that were
collectively much worse, such as overproduction, long lead times, poor response to changes in
demand, and long waits between processes as products waited for the next department to finish
its big
batch
and changeover.

In dentistry, conventional training told dental students to schedule patients by batching like
procedures to avoid setups. When I made your appointment I would see how many fillings you
had and I scheduled them together, said Bahri. I had a different setup for crowns so the next
time you came, I would do the crowns. Most of the time, dentists tried not to switch from one
type of procedure to another in the same appointment because of the time that it takes to do
setups.

He estimated the typical dental setup of preparing tools and materials takes about 15 to 20
minutes. Thus, a patient needing a root canal and crown even if they are for the same tooth will
need a separate visit for each procedure. The problem is that in your mouth, you need crowns,
fillings, root canals, veneers, etc., Bahri said. So when you come to me, I should have the
flexibility to go from one to the other nonstop. That puts the mouth at the center of the process. www.lean.org

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Batching dental procedures avoids setups but leads to other
wastes
. For instance, if you arrive
for a dental appointment needing a procedure other than the one scheduled (like a root canal
instead of a filling) the tools and materials for the scheduled procedure must be removed while
tools and materials for the new procedure are set up. Even if the appointment goes according to
plan, traditional scheduling extends treatment time. For example, if you need a root canal, two



This schedule shows work organized by batch and function in a typical dental
office. The hygienist s chair (right column) is scheduled separately from the two
dental chairs. Note how dental procedures are batched. The A for amalgam
shows a series of fillings scheduled for patients at 9 a.m. and 2 p.m. Source:
Appointment Scheduling by James Pride.
www.lean.org

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fillings, and four veneers, you ll need at least three appointments. That means three roundtrip
drives to the dentist, three periods away from work or leisure, and three times the chance that at
least one appointment will have to be rescheduled.

Bahri saw other parallels between industry s traditional mass production thinking and the
traditional thinking about how to organize dental work. A traditional mass producer groups
machines by functions: the milling machines in one department, drills in another, grinders in
another, etc. Production control schedules the movement of batches of parts from one functional
department to another, creating waste every step of the way from overproduction, undiscovered
defects, and unnecessary transportation to name a few.

Bahri s original office, like a
factory, was organized by
functions. He and two other
dentists along with their
assistants worked in the dental
department, a row of
treatment cubicles dedicated to
dental procedures at one end of
a hallway. At the other end,
hygienists worked in a row of
cubicles with chairs dedicated
to hygiene.

It was organized like mass
production. I wanted to change
that, said Bahri, who has been
recognized as the world s first
lean dentist at a Shingo Prize
conference. I don t think
healthcare professionals realize
how much their offices are
influenced by mass production
assembly lines. Lean principles
identify activities that consume
time or other resources but
don t add value from the
patient s point of view. By
removing these wasteful
activities, a lean transformation
gives healthcare professionals
more time and resources to
spend on personal patient
care.


Conventional dental office management organizes the
office by functions.
440 Feet
The red and blue lines show a hygienist making two round
trips from the hygiene department at the right side of
Bahri s office to dental chairs at the opposite end.
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Starting the Lean Journey
Bahri suspected the departmental arrangement created a lot of walking and delay as hygienists
walked 100 feet from their end of the hallwa