A new concept in maxillary implant surgery the osteotome technique

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A New Concept in Maxillary lmplant
Surgery: The Osteotome Technique
Robert B. Summers,DMD
Practice Limited to Periodontics and
lmplantology
Ardmore, Pmnsylaania
Attending Staff
Bryn MnwrHospital
Bryn Mnwr,Pmnsylaanin
Implantology Staff
Albcrt Einstein Medical Cmt er
Guest Lecturer
Unionsity of P.ennsylaania School of
DmtalMedicine
Phikdelphia, P ennsy la ania
Editor's Note: The Compen-
dium rs pleased to introduce a nans
surgical methodology t'or maxillary
implant placement.This article is
tLre first ot' a fuur-part sqies dnoted
to the osteotome technique. Oaerall
concepts are provided in this issue.
Part 2 Apnl199q wiI detail ridge
enlargement procedures. Part 3
(fune L994) will describe a less in-
aasit:e sinus elwation surgery. A
final article will deal with the
tuberosity. We are pleased to bring
thb technique to your attmtion.
Abstract
This article reviews the limitations of drilling into soft bone to place
endosseous implants. Differences among bone types and the anatomy
of the maxilla are described. The osteotome technique, which is a new
method of placing implants into maxillary bone without drilling, and
the rationale for two other procedures, the osteotome sinus floor eleva-
tion and the ridge expansion osteotomy, are detailed. How osteotomes
conserve osseous tissue and may improve bone density around the im-
plant is also discussed. A pilot study that shows excellent results with
several types of press-fit implants using the osteotome technique is pro-
vided. The author concludes that the osteotome technique is superior to
drilting for many applications in soft maxillary bone. Furtherutore, the
osteotome technique allows more implants to be inserted in a greater
variety of sites during a routine office procedure.
Learning Objectives
After reading ihis article the reader should be able to:
. explain the advantages and rationale of the osteotome technique
compared to drilling in the maxilla.
. describe the osteotome technique.
. recognize the potential applications of the osteotome technique.
o describe two new procedures, the osteotome sinus floor elevation
and the ridge expansion osteotomy, performed with the osteotome
instruments.
he standard method of pre'
paring a bone site to receive
an endosseous implant (the
osteotomy) involves the removal
of bone with a graded series of
drills of increasing sizes. The larg-
est driil in the series approximates
the length and diameter of the
implani to be inserted.l In areas
where there is adequate bone of
good quality, a careful surgical
technique with drills can produce
consistent results.2j
In the mandible, Briinemark
classificaiion type I and II bone
predominates. Lr this area, drilling
is the practical and convenient
means of placing implants.3-s A
dense crestal cortex is generally
available for initial fixation of the
implant. Often the implant can be
placed to take advantage of one or
both of the buccal and lingual cor-
tical plates.{5
Placing implants in the maxilla
152 Compend Contin Educ Dent, Vol. XV. No. 2
Figure 1A-Different bone types. Type I
is homogeneous compact bone.
\--r'
Figure lB-Type ll bone has a thick cor-
tical layer and a dense core.
Figure 2A-The osteotomes developed
by the author.
Figure 1C-Type lll bone has a thin cor-
t ica l layer and a t rabecular core of
good strength.
Figure 2B-Note the Goncave tips and
continuous taper.
implant surgeons. Long-term,
multicenter studies verify that re-
sults with drilling in type IV bone
have not approached the success
rates of drill ing into other bone
types.t2 The literature is replete
with cautionary statements about
the diminished potential of the
maxilla compared with the man-
dible for routine drill ing proce-
dures. A more conservative ap-
proach is generall/ advissd.z,a,e
Less cantilevering is used in the
maxilla, and shorter-length im-
plants are avoided unless bone
quality of the implant site is good.
Fixed cases in a resorbed maxilla
often end around the second pre-
molar because of the sinus.2 More
traumatic surgery, such as sinus
or ridge-crest grafting, has been
the alternative used to compensate
for anatomic and bone-quality
limitations.r3ra
The Osteotome Technique
Because of the problems of drill-
ing in the maxilla, this article pre-
sents a means of osteotomy prepa-
ration in which the bone is not
Figure 1D-Type lV bone has a thin
cortical layer and a cancellous core of
poor strength.
presents a different set of surgical
problems compared to the man-
dible. in the maxilla, the bone is
generally type III or [V.]5 The hard
cortex is thin or entirely absent. Re.
sorption and prominent sinuses of-
ten limit the number of good sites
available for a routine procedure.
Spiny ridge areas, too narrow in
buccopalatal dimension for drill-
ing, are common2i,6 (Figure 1).
The qualitv of maxillary bone
can be extremely variable in a
single location. It is likely that a
maxilla will contain voids, fatty
marrow, and fibrous inclusioni.
The resorbed maxilla is generally
an undercut shape, so that the sur-
geon is forced to place implants
with a flared inclination toward
the buccal. The arch form results in
more difficult emergence angula-
tions and complex abutment
needs.T'8'10
As osteotomy preparation pro-
gresses toward the posterior, the
surgeon usually notices softer
bone texture. The ability to drill ac-
154 Compend Contin Educ Dent, Vol. XV, No. 2
curately in the posterior maxilla di-
minishes with the loss of tactile
sensitivity in soft bone when using
rotating insfruments. Also, inad-
vertent sinus penetration and
overpreparation of soft bone is
corunon with drills. Other factors,
such as torquing of the handpiece
and reproduciog a consistent angle
of penetration, become more de-
manding as bone density de-
creases in the posterior maxilla.e'll
With the drilling technique, vis-
ibitity is reduced in the posterior
maxilla because the handpiece and
contra-angie obscure the surgeon's
vision. To compensate for loss of
tactile sensitivity and provide con-
trol in soft bone, the surgeon must
place both hands as close as pos-
sible to the rotating drill, blocking
the line of sight. Adjacent and op-
posing teeth limit access, and the
irrigation stream required for drill-
ing further impairs visualization.
The frustration of placing im-
plants with drills in soft maxillary
bone has been experienced by all
W,
'removed. This method is called the
osteotome technique. The obfective
of this technique is to maintain, if
possible, all of the existing maxil-
lary bone by pushing the bone
aside with minimal trauma while
developing an accurately shaped
osteotomy. The osteotome tech-
nique attempts to retain all of the
bone that is present, and to take
advantage of the softer bone qual-
ity by relocating the bone to suit the
needs of the surgery. In addition,
pushing or tapping the osteotomes
into place hopefully will compact
the osseous layer around the oste-
otomy, which will form a denser
bone interface with the implant(Figures 2A and 2B).
Drill ing always takes bone
away from a site. Often there is a
marginal quantity of bone to
start with. During the driliing pro-
cess, there is no practical means to
immediately improve adjacent
bone quality. In addition, drilling
creates heat, which is the main ob-
stade to osseointegration. With the
osteotome technique, the bone
layer next to the osteotomy can be
improved because of the instru-
mentation used to prepare the site.
This potentiai compaction of bone
may heip to maintain fixation of
the newly placed implanr. Also,
the osteotome technique is essen-
tiaily heatless (Figure 3).
Expansion of the Ridge
ln contrast to drilling, the osteo-
tome technique improves maxil-
lary anatomy by widening the
ridge as the instruments are in-
serted.The osteotomes, developed
by the author (Summers Osteo-
tome Kit"), are shaped so that the
next larger osteotome tip fits into
the opening created by the previ-
ous instrument. Bone buccal and
palatal to the osteotomy is pushed
laterally with successive penetra-
tions of the larger osteotomes. In a
narrow ridge, expansion of the
a Implant Innovations, Inc, West Palm
Beach, FL 33407
Figure 3-The bone layer adjacent
ostestome technique.
to the osteotomy is compacted wi th the
I I
l n r o s " l l O I
: - 1 . . ' . . .
w Nr \ 4M
FigureLRidgeexpansionosteotomycanbeittempt.aat@
3 mm. Buccal and lingual bone movei laterally as the osteoto-", ur" inserted.
buccopalatal dimension of the site
is an inherent beneficial character-
istic of the osteotome technique.
This is called a ridge expansion
osteotomy (REO), in contrast to a
drilled site, in which the bucco-
paiatai bone width is not changed.
The REO (Figure 4) allows more
narrow ridge sites to be used for
implants within the scope of a rou-
tine office procedure.
The osteotomes have concave
tips with a sharpened edge. This
design allows the instruments to
shave a layer of bone from the side
wall of the osteotomy during in-
sertion. The concave tips tend to
coilect and hold bone, assisting in
pushing this material in front of
the advancing osteotome. Addi-
tional bone can be added from the
adjacent ridge or another source
Compend Contin Educ Dent. Vol. XV, No.2 l55
Figure5_Theo5teotomesjnusf|oore|evation(os@ntofthe
penetrating osteotomes, allowing the sinus floor to be displaied upwards.
Figure 6A-The small diameter osteo-
tome (No. 1 size) is shown starting the
osteotomy into the tuberosity.
Figure 7A-Osteotome technique distal
to a remaining molar.
and conveniently carriedinto the
osteotomy with the instnrments.
The piling up of bone in front of
the osteotomes facilitates elevation
of the sinus floor. The osteotome
sinus floor elevation (OSFE) proce-
dure is simpler, more predictable,
probably safer, and less traumatic
than previously described tech-
niques Figure 5).
Although access is an issue with
any technique in the posterior
maxilla, osteotomes have an ad-
vantage to drilling in most cases.
The surgeon's hands are placed
well away from the penetrating
tips, providing improved visibility.
The straight-line shape and long
handles of osteotomes facilitate
precise control and alignment with
landmarks and paralleling pins.
Also, there is no irrigation stream
to obscure the surgeon's vision.
156 Compend Contin Educ Dent. Vol. XV, No.2
Figure 6B-Osteotomy near completion
wi th a No. 3 osteotome inser ted to
10 mm.
Figure 7B-Access is adequate for a sec-
ond implant.
Osteotome Access Into the
Edentulous Tuberosity
The entire posterior maxilla, in-
ciuding the tuberosity, is usually
accessible for straight-in osteotome
use (Figures 6.4. through 6C). Even
if a maxillary molar remains, oste-
otomes frequently can be used
with precision distal to the remain-
ing tooth. When the moiar area is
edentulous, probing and position-
ing with osteotomes in thai entire
segment is possible in an average
patient (Figures 7 A and 7B).
One advantage of osteotomes
over drilling anywhere in the max-
illa is in terms of tactile sensitivity.
The instruments are extremely
sensitive to changes in bone tex-
ture and density, so they are useful
for probing. This feature allows the
surgeon to locate the best quality
bone in a site by penetrating and
Figure 6C-ln a partially edentulous pa-
tient, three consecutive osteotomy sites
prepared wi th the osteotome tech-
nique. Three 13-mm hexcyl inder im-
plants were placed.
redirecting the smaller diameter
osteotomes along differing axes.
Often there is a tactile difference in
the bone next to the sinus that can
be discerned with the osteotomes.
The instruments are relatively non-
destructive compared to drills
when used as penetrating probes,
so a site usuady is not degraded or
destroyed by the probing process.
Other potential benefits of the oste'
otome technique indude:
1. Alteration of the anterior or pos-
terior sinus boundary during a
routine osteotomy.
2. More upright (less flared) posi-
tioning of implants. The oste-
otome technique provides
greater flexibilify for the surgeon
to match opposing landmarks
because of the REO feature.
3. Development of future implant
sites.
4. Addition of bone into the oste-
otomy as the site is developed.
Upcoming articles will appear
inThe Compendium that will detail
the use of the ostestome technique
for REO, OSFE, and the tuberosity.
Methods and Materials
This report will encompass
L43 consecutively placed press-fit
implants of severai shapes and
diameters inserted into type IV
bone by the osteotome technique.
Both hydroxyapatite-coated and
Table l-lmplants By Type and Design
Type
Micro-VenPn
Micro-VenP
Integraleb
Hexcylinder
Hexcylinder
Hexrylinder
Hexcylinder
Total
Diameter
3.25 mm
4.25 mm
4.0 mm
3.3 mm
4.0 mm
3.3 mm
4.0 mm
Surface
HA
HA
HA
HA
HA
TPS
TPS
Hex
Internal
Internal
None
External
External
External
External
No. Placed
40
55
7
6
1 5
8
' t2
143
aDentsply/lmplant Division, Encino, CA 91436bCalcitek, Inc, Carlsbad, CA 92008
Table 2-Period of Studv
Stage I surgery
February 1990 to March 1992
Stage ll surgery
September 1990 to
September 1992
Months of
Loading
27
21
1 8
1 6
1 5
1 1
lmplant Length Number.
8 m m
1 0 m m
'13 
mm
15/16 mm
Location
Anterior
Premolar
Molar
Tuberosity
Average months of loading:
I8 months
Average age of patients: 59 years
Number of patients in study: 55
'22j6 of implants in study
Number
of lmplants
1 8
1 9
36
32
32
6
1
43
71
28
Number
32*
u
1 6
31
titanium-plasma-spray (TPS)-
coated implants were used in the
study.
It should be noted that many of
the implants used in this study
have a neck design that is wider
than the shaft. In spite of careful
bone preparation with osteotomes,
in spongy bone, it was often the
larger-diameter neck that ailowed
initial fixation of the implant. Pre-
operative evaluation and stent fab-
rication were performed in the
customary manner. Some of the
patients had preoperative com-
puted tomography scans. Final de.
termination of bone type was
based on clinical assessment dur-
ing surgery. Table 1 lists the type
of implants used in the osteotome
study group/ and Table 2 shows
the loading time and location of
theimplants.
Results
All impiants in the study have
been judged by standards as rec-
ommended by Albrektsson et al,rs
SHd,r6 and van Steenberge.tT Peri-
odic films were taken to assess
bone height and quality. Loss of
bone height around the implanis
must be less than 2 mm for im-
plant success. Each implant had to
be immobile continuously when
evaluated bimanually. Sixteen per-
cent of the final prostheses were
158 Compend Contin Educ Dent, Vol. XV. No.2
cemented and could not be re-
moved for inspection of mobility
of individual implants. Two of the
implants in the study are listed as
fai lures because of mobi l i ty. A
treated ailing implant is also listed
as failed (Table 3). All other im-
plants in this study met the criteria
for successful,loaded implants to
the date this article was submitted
for publication.
Discussion
The author has used the osteo-
tome technique in the maxilla for
the lasi 5 years with consistently
excellent results. Both screw-shape
and press-fit implants have been
used. The instruments presented
were not designed for any specific
type of implant. However, the
author's clinical experience indi-
cates that press-fit implants are
best suited to the osteotome tech-
nique. An attempt was made to in-
clude sites in this study that would
be considered difficuit or high risk
because of:
1. very softand spongy bone;
2. spiny ridge segments of less
than 4-mm buccopalatal width;
3. sites with less than 10 mm of
preoperative bone height adja-
cent to or beneath the sinus.
In all of these situations, the use
of osteotomes appear superior to
drilling. The author estimates that
20Vo of the sites in this study could
not have been adequately devel-
oped with routine drilling tech-
niques. The reader should note
that 99 of 743 implants in this
study were 13 mm or longer.
Aside from the tuberosity, where
longer implants would be ex-
pected, to some degree, the im-
plant length related to the sur-
geon's ability to alter the floor and
boundarv of the sinus with osteo-
tomes, which provided a deeper
site.
Drilling does not improve local
anatomy or bone quality. Osteo-
tomes allow a simple means to ex-
pand the ridge, deepen sites, create
I
t}
?
-j
{
a
Table 3-Success Rate AfterAverage Loading of 18 Months
Failures No. Results
lmplants lost between insertion
and uncovering 0
Failed during abutment connection 1 (removed)
Failed/infection 1 (removed)
Failed/mobility (still in service) Z (treated/implants are firm)
Failed/ailing (still in service) 1 (treated/good)
Totalfailed 5*
'Total failures (5 of 143 implanS) indicates a 9696 success rate for the osteo-
tome technique in type lV bone with loaded implans at 18 months.
more usable sites, and possibly im-
prove bone quality. The osteotome
technique is heatless and offers ex-
celient tactile sensitivity, control,
and visibility. Torque is nonexist-
ent and access is as good, or better,
than drills in the posterior maxilla.
Conclusion
The osteotome technique is a
useful and predictable procedure
for implant placement in soft max-
illary bone. This technique im-
proves the chances of placing im-
plants throughout the maxilla,
especially around the sinus and in
the tuberosity, during a routine
office procedure. The osteotome
technique is gentle, does not gen-
erate heat, and takes advantage of
available bone by relocating it in a
variety of surgical applications.
For many patients, the osteotome
technique can help simplify im-
plant surgery by reducing the
need for more traumatic, time-
consuming, and costly procedures.
Acknowledgment
The author wishes to acknowl-
edge the counsel of Drs. Leonard
Abrams, Charles Berman, Richard
Lazzara, and D. Walter Cohen in
the development of this project. A
special thank you is extended to
professional artist Robin Pierce of
Implant Innovations,Inc., who ex-
ecuted the illustrations contained
in this artide.
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160 Compend Contin Educ Dent, Vol. XV, No.2
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