Download year - Pacific Coast Society of Orthodontists

PCSO
at a glance
AAO
Council Members
Component
Societies
Communications
Robin Jackson
ALASKA
President: Jeff Symonds
Pres. Elect: Brian Hartman
Sec.-Treas.: Derek Priebe
Information Technology
Richard Savage
Insurance
Barton Soper
ALBERTA
President: Biljana Trpkova
Vice Pres.: Keith King
Sec.-Treas.: Mike Bleau
Government Affairs
Greg Ogata
Officers and Directors
ARIZONA
President ............................................................................ Ronald Wolk
President: Chris Murphy
President-Elect ...........................................................................Ken Kai
Pres. Elect: Maryam Saiar
Sec.-Treas.: Michael Feinberg Secretary-Treasurer ............................................................... Lili Horton
New and Young Members
BRITISH COLUMBIA
President: Ritchie Mah
Vice Pres.: Jonathan Suzuki
Sec.-Treas.: Tom Moonen
CALIFORNIA
President: Kathleen Nuckles
Vice Pres.: John Trotter
Sec.-Treas.: Tom Chin
HAWAII
President: J. Mickey Damerell
Pres. Elect: Gerald Kim
Sec.: Michael Wall
Treas.: Shelly Kawamoto
IDAHO
President: Gregory Guymon
NEVADA
President: Marc Handelin
Sec.-Treas.: Frank Washburn
OREGON
President: Darrell Angle
Vice Pres.: Rachel Glancy
Sec-Treas.: Joe Safirstein
SASKATCHEWAN
President: Ross Remer
Sec.-Treas.: James
Stephenson
WASHINGTON
President: Bruce Hawley
Vice Pres.: Mario Chorak
Sec.-Treas.: Paul Lund
Membership
Randall Ogata
Directors:
Alaska ........................................................................... John Murray
Alberta, Canada ..................................................... Mark Antosz
Arizona ....................................................................... James Galati
British Columbia, Canada ............................................. Bryan Hicks
California .................................. Harry Dougherty, Jr., Ken Fischer,
Kathleen Nuckles, Michael Ricupito, Glenn Sameshima,
John Trotter, Terrie Yoshikane
Hawaii .............................................................................Erik TinHan
Idaho ................................................................................. Mike Gold
Nevada ........................................................................ Carey Noorda
Oregon .............................................................................Doug Klein
Saskatchewan, Canada ......................................James Stephenson
Washington ................................................................Bryan Williams
AAO Trustee ..................................................................... Robert Varner
Past President ................................................................... Howard Hunt
Editor ............................................................................... Gerald Nelson
Executive Director .................................................................. Jill Nowak
Committee Chairs
Budget & Finance ................................................................... Lili Horton
Bylaws ................................................................................. Ken Fischer
Continuing Education .................................................... Rebecca Poling
Orthodontic Educators .................................................... Joseph Caruso
Meetings: Annual Session General Chair ........................... Paul Kasrovi
Annual Session Member Program Chair ........................Steve Dugoni
Annual Session Staff Program Co-Chairs... Leanne Peniche/Rebecca Poling
Regional Meetings Chairs: Northern .................................... Kari Borgen
Central ............................................................................Mark Douglas
Southern .......................................................................... Darin Iverson
New and Young Members ........................................... Brandy Solomon
Nominating ........................................................................ Howard Hunt
Publications ..................................................................... Gerald Nelson
Northern Editors .............................. Bruce Hawley, William Finnegan
Central Editors ................................. Shahram Nabipour, Robert Quinn
Southern Editor ................................................................ Wanda Claro
Strategic Planning .............................................................. Terry Carlyle
S U M M E R 2 0 0 8 • P C S O B U L L ET I N
Laura Owen-Nichols
Orthodontic Education
Robert Keim
Orthodontic Health Care
Robert MacLean
Orthodontic Practice
Charles Wear
Scientific Affairs
Greg Huang
AAOF Director
Harry Dougherty, Jr.
AAO Delegates
Gary Baughman, Chair
Terry Carlyle
Lili Horton
Howard Hunt
Robin Jackson
Ken Kai
Robert Merrill
Norman Nagel
Gerald Nelson
Lesley Williams
Ronald Wolk
Terrie Yoshikane
AAO Alternates
Harry Dougherty, Jr.
Ken Fischer
Jay Galati
AAOPAC
Representative
Budd Rubin
ABO Director
John Grubb
CDABO Councilor
Michael Guess
13
S E A S O N ED
Practitioner’s
Corner
Dr. Terry McDonald Interviews
Dr. Robert (Bob) Little,
University of Washington Professor Emeritus
D
Part One of a Two-Part Series
r. Robert (Bob) Little began his
teaching career at the University of
Maryland shortly after graduating
from the University of Washington
(UW) orthodontic program in 1970.
After two years, he returned to UW
on a teaching fellowship, where he obtained a PhD
from the UW College of Education with an emphasis
on curriculum design and educational administration.
Along with his UW career, he practiced part-time for
17 years with Dr. David (Dave) Turpin, and also became
ABO certified and joined the Angle Society. He later had
a solo part-time practice in Federal Way, Washington,
while continuing his research and the teaching /
mentoring of graduate students.
During those early years, he worked with Dr. Richard
(Dick) Riedel, combing through and adding to what
became the well-known sample of UW post-retention
cases. He had a hand in many articles and textbook
chapters on the subject, and lectured widely. He is now
Professor Emeritus, retired, and living in Anacortes,
Washington. But retirement has not dampened his
interest in the subject of stability and relapse, nor his
travels to give a lecture or two each year.
TM: To help clarify and guide my own clinical
philosophy, I have long had an interest in the results
of your University of Washington post-retention
studies. How did the collection begin?
RL: “Evidence-based practice” seems to be today’s
mantra, but my mentor and friend Dick Riedel was on
that track over 50 years ago when he first started the
collection by recalling his own ABO cases to assess
stability and relapse of his best-treated cases. Dick said
that he learned so much that he decided to track down as
many of his other patients as he could. When he became
chairman of the department, he expanded the search
to our resident-treated cases. Many of the faculty and
practitioners in the region joined the search by tracking
down their own cases, the result being about 900 sets of
long-term post-retention records.
14
Dick said that the idea of recalling treated cases was not
his. Dr. Charles (Charlie) Tweed had been recalling his
cases for decades before Dick began his search. As you
may know, Charlie’s early treatment mimicked Edward
Angle’s non-extraction, arch expansion philosophy.
Charlie noted significant post-retention relapse of those
expanded cases, and in an effort to correct this perceived
mis-step, he retreated many of them with first premolar
extraction, and at no cost. Dr. Paul Lewis, our venerable
UW mentor, told me that Charlie planned to recall
those cases that had undergone this double treatment
to see if the second round was any better than the first
FIGURE 1.
AGE 13, GENERALIZED SPACING
PRE-TREATMENT
round. Paul said that, unfortunately, an office fire ruined
Charlie’s records and foiled this goal.
TM: Some critics of your work claim better stability
in their hands and blame your findings on the large
number of resident-treated cases in the sample. Would
you agree?
RL: The number of resident-treated cases was a small
portion of the total, perhaps 20%. But one should not
assume that resident-treated cases were necessarily
inferior. All such cases were supervised by faculty and
may have been scrutinized even more carefully than
private practice cases.
P C S O B U L L ET I N • S U M M E R 2 0 0 8
SEA SON E D
Practitioner’s
Corner
However, residents located the majority of the cases in
the collection. Dick was concerned about practitioners
taking records only on their successful cases. As he said,
“Orthodontists love to take records on their winners, but
tend to ignore the losers.” For many years, our residents
had the assignment to locate one, two, or, at one point,
three post-retention cases before they could graduate.
That was Dick’s way to help avoid practitioner bias,
since the students did not care whether the case was
an “A” result or an “F.” The resident just wanted to
graduate.
FIGURE 1.
AGE 16, END OF ACTIVE TREATMENT /
START OF RETENTION
TM: How did you come up with 10 years for the
minimum post-retention period?
RL: In the Pacific Northwest, it was typical to retain the
lower arch with a fixed 3-to-3 retainer for about one or
two years, after which the patients were dismissed from
the practice. So the time clock for us did not start until
that retainer was removed. Many authors and lecturers
at our meetings back then, and still today, showed cases
post-treatment but still in retention, rather than postretention. Dick’s first criterion was for the cases to be
post-retention, not just post-treatment. During the early
collection years, the cases were only one to three years
post-retention. Dick kept bringing the patients back and
noted that there was often no significant relapse until
S U M M E R 2 0 0 8 • P C S O B U L L ET I N
about four or five years post-retention. Relapse seemed
to be more aggressive in the late teens and early twenties,
but then seemed to settle down by 9 or 10 years postretention. The first five years post-retention Dick called
the “Honeymoon Period,” while the 10-year mark seemed
more indicative of the true result. We later learned that
most cases continued a slow decline in quality from 10 to
20 years post-retention, but the major relapse seemed to
occur from age 18 to 25. We gathered records for quite a
number of cases to the 20-year post-retention mark and
several had 30- and 40-year records.
FIGURE 1.
AGE 29, POST-RETENTION 10 YEARS +
TM: Are cases still being collected?
RL: When HIPPA came along, the University of
Washington officials brought our collection of new
records to a temporary halt. The rules became more
strict, but after several years of rule adjustment we were
allowed to continue. Old records were “coded,” that is,
we removed patient identifiers from all records. We also
improved how we obtained patient permission and who
would have access to the records.
I stopped student collection of records during this HIPPA
modification period. If or when residents will resume
record collection will be up to Anne-Marie Bollen, who is
now in charge of the UW collection.
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S E A S O N ED
Practitioner’s
Corner
A serious problem is the deterioration of the
radiographs; particularly the headfilms. A large
percentage of the older films are fading to a point of
not being readable. We have not been successful in
obtaining funding to scan, improve, and digitize those
records, but I am hopeful that this can be resolved.
Perhaps Anne-Marie will be more successful in
obtaining the needed funds for equipment and staff.
TM: What principles seem to shine through that we
clinicians need to remember?
FIGURE 2.
AGE 12, FIRST PREMOLAR EXTRACTION
RL: I am reminded of the work of Dr. Peter Sinclair
while he was a UW resident. Peter studied a serial
collection of untreated “normals” that he collected
from the Burlington Growth Center in Ontario.1 Those
cases had serial records at three time periods: pre-teen,
teen, and early adult. Although all were near perfect in
alignment by the teen and adult stage, what impressed
me was that all had shown arch length and arch width
reduction over time, but without crowding, hence the
label “normal.”
In a later study of cases with pre-treatment mandibular
arch spacing, all showed reduction in arch width and
arch length with time.2 With few exceptions, this group
also displayed excellent long-term mandibular anterior
alignment (Fig. 1.).
16
Crowded cases treated with first premolar extraction
displayed this same tendency of reduced arch length and
arch width with time, but they appeared to relapse more
aggressively. As a group they had much more alignment
relapse than cases with pre-treatment spacing or pretreatment adequate arch length. Premolar extracted
cases had only about a 30% success rate at the 10-year
post-retention stage.3 Unfortunately, we seem unable to
predict at the pre-treatment stage, or at the end of active
treatment, which cases are likely to be a success versus
which will be a failure.
FIGURE 2.
AGE 13, END OF ACTIVE TREATMENT /
START OF RETENTION
By 20 years post-retention, premolar extraction cases had
only a 10% success rate, all demonstrating continuing
arch constriction and increased crowding with time.4
Crowding typically continues at a slower rate after 10
years post-retention, and I feel that most cases will
continue to show gradual increase in crowding
throughout life (Fig. 2.).
Serial extraction premolar cases followed by routine
orthodontics and retention did no better by the 10-year
post-retention stage.5, 6 Serial extraction cases temporarily
showed improved self-alignment shortly after the
extractions, but by the 10- and 20-year post-retention
stages were not distinguishable from the cases extracted
and treated in the full permanent dentition.
P C S O B U L L ET I N • S U M M E R 2 0 0 8
SEA SONE D
Practitioner’s
Corner
In summary, there seems to be a strong physiologic
tendency for the lower arch to constrict in width and
length over time. Those cases with adequate or excess
pre-treatment space fared much better than those that
at pre-treatment were crowded and deficient in arch
length. In my view, retention interrupts this normal
physiologic trend of decreasing arch dimensions. When
the retainer is later removed, normal physiology will
typically reassert itself, more dramatically in some
cases and less so in others.
Certainly there are many more factors to consider. For
a more detailed description of possible risk factors, I’d
suggest reviewing Dr. Perry Ormiston’s article.7 For
those interested, there is a summary article of many of
our studies in Seminars in Orthodontics.8
TM: Bob, we will finish this interview in the next issue
of the PCSO Bulletin. Thanks very much for this review
of your work.
FIGURE 2.
AGE 28, POST-RETENTION 10 YEARS
FIGURE 2.
AGE 39, POST-RETENTION 20 YEARS +
REFERENCES – PART 1
1.
Sinclair, P., Little, R.: Maturation of untreated normal
occlusions. Am J Orthod 83: 114-123, 1983.
5.
2.
Little, R., Riedel, R.: Postretention evaluation of stability
and relapse. Mandibular arches with generalized spacing.
Am J Orthod Dentofac Orthop 95: 37-41, 1989.
Little, R., Riedel, R., Engst, E.: Serial extraction of first
premolars – postretention evaluation of stability and relapse.
Angle Orthod 60: 255-262, 1990.
6.
Little, R., Wallen, T., Riedel, R.: Stability and relapse of
mandibular anterior alignment. First premolar extraction
cases treated by traditional edgewise orthodontics. Am J
Orthod 80: 349-365, 1981.
McReynolds, D., Little, R.: Mandibular second premolar
extraction – postretention evaluation of stability and relapse.
Angle Orthod 61: 113-144, 1991.
7.
Little, R.: Riedel, R., Artun, J.: An evaluation of changes
in mandibular anterior alignment from 10 to 20 years
postretention. Am J Orthod Dentofac Orthop 93: 423-428,
1988.
Ormiston, J., Huang, G., Little, R., Decker, J., Seuk, G.:
Retrospective analysis of long term stable and unstable
orthodontic treatment outcomes. Am J Orthod Dentofac Orthop
128: 568-574, 2005.
8.
Little, R.: Stability and relapse of mandibular anterior
alignment - University of Washington studies. Semin Orthod 5:
191-204, 1999.
3.
4.
S U M M E R 2 0 0 8 • P C S O B U L L ET I N
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