Technique for Placement of Oxidized Titanium Implants by Oded Bahat

The International Journal of Oral & Maxillofacial Implants 325
Technique for Placement of Oxidized Titanium
Implants in Compromised Maxillary Bone:
Prospective Study of 290 Implants in
126 Consecutive Patients Followed for a
Minimum of 3 Years After Loading
Oded Bahat, BDS, MSD, FACD1
Purpose: This prospective clinical study evaluated the performance of 290 tapered, anodic oxidized
(TiUnite) titanium implants placed in compromised bone in a consecutive series of 126 patients. Mate-
rials and Methods: Inclusion criteria were: (1) a need for dental implants in either a single-tooth or
partially edentulous segment, (2) sufficient medical fitness to undergo the procedure, (3) enough bone
to enable placement of a 10-mm or longer implant, and (4) compromised bone, as judged by comput-
erized tomography and confirmed by clinical findings, in at least one implant site. Implants were
placed and left unloaded for at least 6 months (mean 9.9 ± 3.9 months) before placement of the first
provisional prosthesis and followed for at least 3 years after loading. Marginal bone was measured by
an independent radiologist. Results: A second-stage uncovering was required for approximately half
the implants. Failure of osseointegration was observed for only two implants; all other implants pro-
vided the intended prosthetic support during the entire observation period. The overall implant survival
rate after 3 years of loading was 99.3%. The average mean changes in the marginal bone level
showed stability (–2.70 mm, –2.67 mm, and –2.74 mm at 1, 2, and 3 years postloading, respectively).
Conclusions: Using a modified surgical technique that minimized the osteotomy dimensions, tapered
implants with an oxidized surface proved to be a predictable support for fixed prostheses in both
grafted and ungrafted compromised bone. Marginal bone levels were stable throughout at least 3
years of follow-up. INT J ORAL MAXILLOFAC IMPLANTS 2009;24:325–334
Key words: bone grafts, bone quality, dental implants, marginal bone, titanium oxide
Both bone quality and implant surface topography
influence bone response after implantation,1 and
an implant’s surface properties play a significant role
in its success and biocompatibility.2 Titanium dental
implants have been successful in bony anchorage for
single-tooth and multiple units for more than 4
decades. By 1985, researchers recognized that the
titanium itself is not the biocompatible material;
rather,the titanium oxide surface layer is biocompati-
ble.3 An implant with a highly crystalline and phos-
phate-enriched titanium oxide layer characterized by
a microstructured surface with 1- to 10-µm open
pores (TiUnite, Nobel Biocare, Göteborg, Sweden)
better maintains primary mechanical stability and
shortens the time needed to achieve secondary bio-
logic osseous stability than does a machined-surface
implant.4–11 Titanium oxide–enriched implants thus
may be more suitable for use in challenging condi-
tions involving compromised bone.
Implant macrodesign also plays an important role
in the success of implant treatment. Implants with a
tapered body have better primary stability and thus
a higher likelihood of integration than parallel-
walled body designs11–15; this may be because
tapered implants distribute forces into the surround-
ing bone more uniformly. Tapered implants such as
the Replace Select also are associated with more uni-
form compaction of the surrounding bone along the
periphery of the osteotomy and greater early stabil-
ity, permitting successful immediate occlusal
loading12–16 and higher long-term success rates.11
Wider implants are more stable initially, as judged by
1Private Practice, Beverly Hills, California.
Correspondence to: Dr Oded Bahat, 414 N. Camden Drive,
Suite 1260, Beverly Hills, CA 90210. Fax: +310-859-2884.
Email: odedbahat@aol.com
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326 Volume 24, Number 2, 2009
Bahat
resonance frequency analysis, perhaps in part
because of the greater surface area that is in contact
with bone, whereas longer implants are not.16 Fea-
tures that increase primary stability are particularly
important when placing implants in regions of com-
promised bone (eg, type IV bone), where the likeli-
hood of failure is higher.11,16,17
The aim of this study was to evaluate a cus-
tomized osteotomy technique for placement of TiU-
nite Replace tapered implants in compromised bone
with regard to long-term implant stability and main-
tenance of marginal bone.
MATERIALS AND METHODS
Criteria for Selection of Patients
Subjects requiring dental implants were recruited
from the author’s private, referral-based periodontal
practice and included if (1) they were medically able
to withstand the procedures and (2) they either pos-
sessed sufficient residual host bone in three dimen-
sions to allow placement of a 10-mm or longer
implant or could receive reconstructive procedures
to create that amount of bone. Whether residual or
grafted, the bone in at least one site had to be com-
promised (type IVA, B, or C as described by Lekholm
and Zarb18 and by Bahat19) or have no cortical bone
(type V) for the patient to be included in the analysis.
Computerized tomography (CT) scans were obtained
on a GE Discovery 16 scanner (GE Healthcare, Chal-
font St Giles, United Kingdom) with axial slices being
captured at 1-mm intervals. Two-dimensional axial
and panoramic views and three-dimensional bone
views were then constructed. Such scans depict the
type, quality, and quantity of bone accurately. In all
cases, bone status was validated by intraoperative
assessment with instruments.
For all subjects, a comprehensive surgical and
restorative treatment plan was developed.20 This
included a full dental and medical history and preop-
erative intraoral calibrated radiographs in addition to
the CT scans. Medical consultation was obtained to
ensure that all patients were acceptable candidates
for elective surgery. If a subject was initially deemed
unfit, the unfavorable medical or dental conditions
were corrected or minimized. Subjects who were cig-
arette smokers were informed that smoking
increases the implant failure rate21,22 and asked to
comply with a smoking reduction regimen.
Description of Series
Between January 2002 and June 2003, 69 women
and 57 men received a total of 290 consecutively
placed implants with a TiUnite surface (Replace
Tapered,Replace Select Tapered,Nobel Biocare,Yorba
Linda, CA) for restoration of single-tooth and partially
edentulous sites (Table 1). All implants were placed
in the maxilla, with 118 (41%) in the anterior and 172
(59%) in the posterior (Table 2). Type III, IV, or V bone
was present at the sites of placement of 88% of the
anterior implants and 96% of the posterior implants
(Table 3).
Surgical Protocol
All areas of previous infections were curetted
mechanically while being irrigated with chlorhexi-
dine gluconate 0.12% topical oral solution. Sterile 2
ϫ 2-inch gauze sponges impregnated with hydro-
gen peroxide 3% in a 3:1 ratio with chlorhexidine to
peroxide were packed gently into the surgical area
for 3 to 4 minutes.The site was then debrided with a
rotary instrument and further irrigated chemically.
A principal objective was to obtain primary
implant stability. To achieve this in areas of reduced
bone quality, enlargement of the osteotomy site and
the number of surgical entries into each site were
minimized.16,18,23 A final drill with a diameter smaller
than the manufacturer’s recommendation was used,
Table 1 Distribution of Implant Dimensions
Diameter (mm)
Length (mm) 3.5 4.3 5.0 6.0 Total
10 0 13 54 6 73
13 4 63 66 8 141
16 3 38 33 2 76
Total 7 114 153 16 290
Table 2 Diameters of Implants Placed with
Respect to Location
Diameter (mm) Anterior Posterior
3.5 4 1
4.3 61 53
5.0 50 103
6.0 3 15
Table 3 Quality of Bone at Implant Sites*
Bone quality Anterior Posterior
II 14 7
III 74 111
IV 12 24
V 18 30
*Measured as described by Lekholm and Zarb18 and Bahat.19
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Bahat
and a stepped preparation technique was cus-
tomized for each site using traditional twist drills
instead of the tapered/stepped drills (Nobel Biocare,
Yorba Linda, CA) that are part of the normal Replace
Tapered implant drilling sequence. When using the
2-mm twist drill, the cutting resistance was moni-
tored to determine the minimum osteotomy diame-
ter that would seat the implant (Fig 1).
Special care was taken to avoid any deviation
between intended and actual implant positions. For
each patient, intraoral access was evaluated preoper-
atively; it was assessed relative to the length of the
implant and its mount, the various drill selections
and extensions, and any deflection by the lip (Figs 2
and 3). Periapical radiographs were taken intraopera-
tively whenever questions arose regarding implant
position relative to vital anatomic structures.
Whenever insufficient bone was present initially
to enable placement of a 10-mm implant, a two-
dimensional onlay or three-dimensional J-graft plus
sinus inlay autogenous bone graft was performed
(three anterior; 67 posterior). All bony irregularities at
the recipient site were removed, and the site was
smoothed to create maximum surface contact with
the bone block.A flap with anterior advancement was
used prior to closure to gain additional tissue range
and achieve primary closure of the expanded surgical
site.24 These flaps require precise design, gentle
manipulation, and repeated trial closure to prevent
undue tension. The sites of all staged autogenous
bone block grafts were allowed to heal for a minimum
of 6 months before implants were placed. At both
grafted and native sites,particulate autogenous bone
was used to fill in small spaces around the implants
at the time of their placement.All implants had either
a cover screw or a short healing abutment placed for
an unloaded two-stage or one-stage protocol.
A radiograph was obtained immediately after
surgery. Antibiotics and nonsteroidal anti-inflamma-
tory drugs were given to all subjects, who were
instructed to use ice packs and consume cold drinks
for 3 days.Chlorhexidine rinse was prescribed for 2 to
3 weeks, along with the use of cotton swabs soaked
with chlorhexidine 3 to 4 times a day for 3 to 4
months.
Follow-up evaluation of the subjects was at
weekly or biweekly intervals for the first 2 months.
Any negative soft tissue changes or adverse reac-
tions were addressed by immediate intervention,
including removal of debris or foreign bodies and
irrigation with chlorhexidine, hydrogen peroxide, or
other antiseptic. Whenever these interventions did
not eliminate the adverse local reaction, flaps were
raised, cover screws or healing caps were retight-
ened, or loose flaps were coapted. During the healing
period, implant stability, occlusal relationships, and
soft tissue health were monitored regularly.
Restorative Protocol
Whenever possible, fixed provisional restorations
were supported by the remaining teeth, even if they
carried a poor prognosis and ultimately would be
extracted. As an alternative, provisional implants or
additional implants beyond what would normally
have been necessary were placed to support imme-
diate provisional restorations. In all cases, every pos-
sible effort was made to reduce transmucosal load-
ing of the implants. Whenever hopeless teeth served
as abutments for the provisional restorations, these
were later extracted, and implants were placed in
those sites after the initial (study) implants had
osseointegrated. The initial implants then supported
a provisional restoration that protected the newly
placed implants.
2.8
3.1
3.4
3.7
4.3
4.3TAPERED10
Ø2mm
Ø3mm
Ø4.3mmFig 1 The Replace Tapered implant uses drills that are stepped at different diameters (black drills at the left of each sequence) and are
intended for use in all bone densities (numbers to the left of the drills specify the varying diameters of these steps, in millimeters). As an
alternative when compromised bone is encountered, a customized stepped site preparation method can be used with straight drills
instead of the manufacturer’s design to minimize site preparation based on perceptions of bone density. Note that in compromised bone
the 4.3-mm diameter is the last drill used for the wide-platform 5-mm-diameter implant.
3.5
3.9
4.2
5.0
4.3TAPERED10
Ø2mm
Ø3mm
Ø4.3mm
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Bahat
In situations where it was not possible to protect
the implant from loading,the implant was submerged
and uncovered later. The remaining implants were
treated in a one-stage unloaded protocol. Depending
on soft tissue healing and contours,some of the study
implants received two separate provisional restora-
tions. The first was delivered when the implant was
uncovered or the healing abutment was removed.
After the soft tissue had matured and its contours had
stabilized, the first provisional prosthesis was either
adjusted or replaced by a second one that reflected
the contours of the stabilized tissue. Prostheses were
removed routinely for assessment of soft tissue heal-
ing and implant integration. No impressions were
taken until at least 6 months after implant placement.
Radiologic Analysis
All baseline radiographs were obtained using preci-
sion metal x-ray holders (Masel Orthodontics, Bristol,
PA). All follow-up radiographs that were performed
by the author were also done with this technique. In
28 patients, follow-up of the impression technique or
abutment placement was done by other clinicians
using the technique employed by the author, digital
radiographs, or a Rinn Uni-Grip holder (Dentsply,
Elgin, IL). Radiographs were planned for the day of
implant placement, the time of impression coping
placement or abutment placement and provisional-
ization, and at successive 6-month intervals through
at least 36 months from the date of provisional
restoration placement. Additional radiographs were
Fig 2a Careful attention is required to
maintain the planned three-dimensional
alignment.
Fig 2c Improvement of surgical direction
may be effected by use of longer drills or a
drill extender. The preoperative workup
should include interarch access assessment.
Fig 2b If the overall drill length is too short
relative to existing anatomic structures,
there is a risk that the drill orientation will
drift during further access of the site.
Fig 2 Steps in placement technique.
29 mm
34 mm
39 mm
46 mm
51 mm
35 mm
43 mm
4.3SEL
4.3SEL
Fig 3b In addition to drilling direction, with compromised bone
it is imperative to maintain direction during the insertion of the
implants. Different lengths of implant insertion instruments help
maintain the desired three-dimensional axial orientation. (Height
measurement includes handpiece angle head as measured with
a 10-mm implant as an example.)
Fig 3 Further details of implant placement technique.
7–10 7–15 13–20
7–10
w/ext
7–15
w/extLength (mm)
Fig 3a To help maintain the intended axial direction when
teeth impede access, drill lengths are chosen to balance optimal
access with available interarch opening ability of the patient.
Shown as examples are the 2-mm Brånemark System drills in
three different lengths with drill extenders to ensure the best
length for access and orientation. (Height measurement includes
handpiece angle head.)
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Bahat
obtained if the patient reported pain or discomfort
or if there was deterioration of the soft tissues. The
images were examined for vertical bone loss and
radiolucency around the implants.
Using the implant-abutment junction as a refer-
ence point, the marginal bone levels on the mesial
and distal aspects of the implants were measured to
the nearest 0.1 mm at 7ϫ magnification by a single
independent radiologist at Göteborg University,
Göteborg, Sweden. A negative value indicated bone
apical to the reference point.All bone levels that were
coronal to the reference point were recorded as zero.
Once the definitive restorations were luted, the
metal-ceramic restorations were not removed rou-
tinely. All subjects were questioned periodically
about pain and chewing function.
Statistical Methods
Descriptive statistics and actuarial life table analysis
were used to calculate cumulative survival rates. The
Mann-Whitney U test was employed to compare mar-
ginal bone levels of implants placed in grafted and
nongrafted sites and conducted at the 5% significance
level based on the implant as a unit. Implant success
was defined as suggested by Albrektsson et al.25
RESULTS
Evaluation using an electric handpiece (DEC 500;
Nobel Biocare) demonstrated that all implants were
fully seated and stable at the determined length to
an applied minimum of 40 Ncm without further rota-
tion.18 In the approximately 50% of treatments that
required a two-stage approach, the original provi-
sional restorations were remade 2 to 3 weeks after
second-stage surgery. An acrylic resin provisional
restoration was placed on all the implants for a mini-
mum of 3 months before a metal-ceramic restoration
was provided. For all implants, the first provisional
restoration was placed an average of 9.9 ± 3.9
months after implant placement.
Radiographic analysis of 128, 167, and 80 implants
was possible at the 1-, 2-, and 3-year postloading fol-
low-up appointments, respectively. Seventeen
patients (19 implants) were dropped from the study
because of poor compliance. In addition, one patient
died and could not be followed after the time of
loading. Two implants failed, both anterior and both
in the same subject, within 1 year after loading. After
3 years of postloading follow-up, life table analysis
revealed an overall cumulative survival rate of 99.3%
(95% confidence interval, 98.0% to 100%) for the
entire series, 98% for anterior implants, and 100% for
posterior implants (Table 4).
The greatest change in marginal bone levels
occurred between the time of implant insertion and
loading. The mean marginal bone level at implant
insertion was –0.53 ± 0.93 mm (n = 263), while at the
time of loading it was –2.08 ± 1.07 mm (n = 232).
Thirty-two percent of the implants showed a bone
loss exceeding 2 mm between the time of implant
insertion and loading. Bone loss before loading is
more likely in areas of poor-quality or reconstructed
bone, and healing can take considerably longer than
6 months, again calling attention to the importance
of customizing treatment to each patient’s individual
situation. As indicated in Table 5, stabilization of mar-
ginal bone levels occurred after 1 year of follow-up.
At the 3-year postloading follow-up, the mean mar-
ginal bone level was –2.74 ± 1.06 mm (n = 80). From
the time of loading to the 3-year follow-up, the mean
marginal bone loss was 0.67 ± 1.06 mm (n = 64). No
individual implant showed more than 4.75 mm of
bone remodeling during the 3-year follow-up period.
Seventy sites (24%) were subjected to bone graft-
ing. The mean marginal bone levels were similar for
implants placed in grafted and nongrafted sites:
–0.62 ± 0.99 mm (n = 59) and –0.51 mm ± 0.92 mm
(n = 204), respectively. However, a significantly higher
mean marginal bone level was found at the time of
loading in grafted sites: –1.83 ± 0.94 mm (n = 58) ver-
sus –2.16 ± 1.11 mm (n = 174) for ungrafted sites (P =
.035). Twenty-one percent of the implants placed in
Table 4 Overall Cumulative Survival Rate
Implants lost
No. of Implants Death/ Missed Cumulative
Time implants surveyed failed withdrawal appointments survival rate (%)
Placement–loading 290 0 1 0 100.0
Loading–1 y 289 2 35 20 99.3
1–2 y 232 0 1 23 99.3
2–3 y 208 0 1 122 99.3
> 3 y 85 – – – –
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grafted sites and 35% of the implants placed in
native bone showed bone loss exceeding 2 mm
between the time of implant insertion and loading
(Table 5). No clinically significant differences were
found between implants placed in grafted sites and
those placed in nongrafted sites when comparing
bone levels at any other follow-up examination. As
indicated in Table 5, bone remodeling after loading
was minor for implants placed in both grafted and
nongrafted sites. At 3 years after loading, the mean
marginal bone level for grafted sites was –2.53 ± 1.05
mm (n = 26) and for nongrafted sites it was –2.83 ±
1.06 mm (n = 54). This amounts to a loss of 0.43 ±
1.07 mm (n = 22) of marginal bone at grafted sites
and 0.79 ± 1.04 mm (n = 42) at nongrafted sites from
the time of loading to the 3-year postloading follow-
up examination (Figs 4 to 6).
DISCUSSION
Implant survival in grafted or compromised maxillary
bone has undergone steady improvement over the
past 25 years. In 1991, Jaffin and Berman reported a
65% 5-year survival rate among implants placed in
type IV bone.26 In 1999, Lekholm et al reported a 77%
overall 3-year survival rate for implants placed in
sites augmented with various autogenous grafting
methods.27 In 2005, Wiltfang et al showed an overall
5-year success rate of 93.1% for implants placed in
sinus inlay and autogenous onlay graft sites in the
severely resorbed maxilla.28 That study also demon-
strated early bone loss, associated with grafts, that
stabilized after 12 months. The current finding of an
Bahat
0.0
–2.0
–4.0
–6.0
–8.0
–10.0
Marginalbonelevel(mm)
**
**
*
*
Implant
insertion
Loading
*
*
1 y
*
2 y 3 y
Fig 4 Box plot of all available values on marginal bone level at
the different follow-up visits. Boxes show medians, quartiles, and
extreme values. Circles show outliers (cases with values between
1.5 and 3 box lengths from the upper or lower edge of the box).
Asterisks show extreme cases (cases with values more than 3
box lengths from the upper or lower edge of the box). The box
length is the interquartile range.
Table 5 Marginal Bone Loss (mm) Between Implant Insertion and Loading
and Between Loading and 3-Year Follow-up
No. of implants
Time/mean loss (mm) All sites (%) Grafted sites (%) Nongrafted sites (%)
Insertion–loading
< 0 9* (4) 2 (4) 7 (4)
0 19 (9) 4 (8) 15 (9)
0.1–1.0 46 (21) 15 (28) 31 (19)
1.1–2.0 74 (34) 21 (40) 53 (33)
2.1–3.0 52 (24) 10 (19) 42 (26)
3.1–4.0 10 (5) 0 (0) 10 (6)
> 4.0 6 (3) 1 (2) 5 (3)
Mean 1.54 1.34 1.60
SD 1.22 1.01 1.28
No. of implants surveyed 216 53 163
Loading–3 y
< 0 15 (23) 4 (18) 11 (26)
0 4 (6) 2 (9) 2 (5)
0.1–1.0 25 (39) 12 (55) 13 (31)
1.1–2.0 17 (27) 4 (18) 13 (31)
2.1–3.0 1 (2) 0 (0) 1 (2)
3.1–4.0 1 (2) 0 (0) 1 (2)
> 4.0 1 (2) 0 (0) 1 (2)
Mean 0.67 0.43 0.79
SD 1.06 1.07 1.04
No. of implants surveyed 64 22 42
*Mean of mesial and distal values.
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Fig 6 Another example of outcome.
Fig 6a Preoperative radiograph shows sig-
nificant deficiency of residual alveolar bone.
Figs 6b to 6e Intraoperative photographs
show three-dimensional reconstruction. Sinus
inlay grafting is most apparent radiographi-
cally; horizontal and vertical cranial cortical
grafts were used to reconstruct the arch pro-
files. Strategic temporary use of hopeless
teeth helps prevent early transmucosal load-
ing of graft.
Figs 6f and 6g Radiographs at (f) 8 months
after grafting and (g) nearly 2 years later.
Fig 6h to 6j (h) Implants at start of restora-
tive process. (i) One-year follow-up radiograph.
Note that the right second molar was re-
moved after its use for support of the provi-
sional restoration. (j) Two-year follow-up
results. Early bone loss has not worsened.
Fig 5 Example of outcome. (a) Preopera-
tive view of a severely periodontally involved
right quadrant. (b) Time of discharge to
restorative clinician after healing abutment
placement. (c and d) Radiographic follow-up
at 26 months.
a b
c d
ba
h
c
d e
f g
i j
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overall 99.3% 3-year postloading survival rate for
implants placed in compromised and grafted sites is
a gratifying extension of that overall trend of
improvement.
Increasing knowledge regarding the proper han-
dling of dental implants and a deeper understanding
of implant surface–bone interactions have con-
tributed to the improved survival rates.The results of
the present study as well as others indicate that
modifications to the implant placement surgical
technique, the implant surface,15,29–31 and the
implant macro design32,33 are particularly important
to the survival of implants.
Studies have shown a more robust early bone
response to the TiUnite surface than to machined
surfaces.4–10 When Glauser et al compared machined
and TiUnite surface Brånemark System implants in
immediate loading applications, they found that the
TiUnite surface implants exhibited significantly bet-
ter survival rates.15,30 Results similar to those of the
current study also have been reported when TiUnite
surface implants were placed in patients subjected
to reconstructive jaw surgery or in soft bone.12,34,35
In addition to the oxidized surface, implants in the
current study had a tapered body. Previous results
have indicated that implants with this design distrib-
ute forces into the surrounding bone in a more uni-
form way than parallel-walled self-tapping implants,
and they are associated with more uniform com-
paction of the surrounding bone.12–15 The primary
stability of tapered implants has been superior to
that of implants with straight-body designs.10 Cumu-
lative survival rates between 98.6% and 100% have
been reported when placing such implants.36,37 This
is well in line with the current study results.
The finding in the present study that the use of a
wide implant in a socket with undermined or
thinned cortical bony housing and thin periodon-
tium stood a greater likelihood of recession (3 of 53
cases) suggests that extra care should be taken when
planning to place wide-diameter implants in estheti-
cally critical compromised sites.
Albrektsson et al suggested that six variables
determine lifelong dental implant integration38: (1)
biocompatibility of the material, (2) implant
macrostructure (shape), (3) implant microstructure
(surface), (4) status of the implant bed, (5) surgical
technique, and (6) prosthetic loading conditions. The
current study focused on three of these variables.
Two of these variables are controlled by the manu-
facturer: the implant macrostructure (tapered shape)
and its microstructure (larger oxidized surface area
achieved via greater porosity). The third variable is
surgical technique. For this study, the dedicated
tapered drills provided by the manufacturer were
replaced by straight twist drills that provided a cus-
tomized stepped preparation.
In the author’s opinion, surgical technique is of
utmost importance when working in soft and recon-
structed bone. Two aspects warrant special empha-
sis: ensuring that the desired three-dimensional ori-
entation is achieved and undersizing of the site
preparation. Maintenance of the intended three-
dimensional orientation is important for optimal
structural support of the restoration. Furthermore,
misangulation can compromise the blood supply to
fragile soft tissue and supporting bone, which in turn
can lead to late soft tissue loss,with negative esthetic
consequences. Preservation of the intended orienta-
tion in areas of soft and reconstructed bone when
access is limited by adjacent teeth and opposing
dentition requires a thorough three-dimensional
evaluation of the site anatomy as well as selection of
the optimal armamentarium for execution.
Deviations of drill direction in soft bone constitute
an inherent risk and should be avoided. Any
unplanned deviations should be counted as implant
failures, as should any positioning that jeopardizes
esthetics or phonetics. Causes of drill directional
deviation include use of self-tapping implants and
inadvertent nonaxial orientation, along with pressure
of the drill or implant mounts during drilling.
Although self-tapping implants have certain inser-
tion advantages for seating implants in dense bone,
these implants present disadvantages when soft,
compromised bone is encountered. First, the sharp
threads of self-tapping implants cut through soft
bone. In contrast, the threads of the tapered implant
used in the present study push and compress the
bone. Second, in soft bone, any deviation of the
implant mount orientation during insertion can
cause the self-tapping implant to cut in the direction
of the nonvertical pressure, because the host bone
does not provide sufficient resistance to maintain
the orientation. Such an inadvertent deflection from
the intended direction may occur because of nonax-
ial pressure by the operator or limitations imposed
by neighboring and/or opposing teeth and the com-
missure of the lip. Deflection caused by the commis-
sure can be avoided by proper preoperative evalua-
tion of intraoral access and the selection of
appropriate drills and implant mounts. When access
is limited, a drill extender can provide the minimal
overall length needed to avoid any unintended
deflection.
It has been well established that surviving
machined implants enter into a steady state with sta-
ble bone levels and an absence of soft tissue inflam-
mation in similar applications with 5- to 10-year fol-
low up.18,39,40 Long-term studies specifically
Bahat
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addressing soft tissue stability and the influence on
long-term esthetic outcomes will be required to
determine whether the oxidized (TiUnite) surface
has a similar impact on hard tissue stability and soft
tissue health.
In the present study, the implant-abutment junc-
tion was used as a reference point from which the
distance to the marginal bone level was measured.
At the 3-year postloading follow-up examination, the
mean marginal bone loss on radiographs of 64
implants was 0.67 ± 1.06 mm from the time of abut-
ment connection. In an earlier study by Glauser et al
evaluating the effectiveness of the TiUnite surface
over a 4-year period in soft bone that used a differ-
ent implant macrostructure and an external hexago-
nal restorative platform, the mean marginal bone
loss was 1.30 ± 0.90 mm.35 However, in the present
study the greatest amount of bone loss, 1.54 ± 1.22
mm, occurred between implant insertion and load-
ing, and a significantly higher mean marginal bone
level was found at the time of loading in grafted sites
than in nongrafted sites. Direct comparison by time
period with the results of Glauser et al is not possi-
ble, because Glauser et al used an immediate
occlusal loading protocol.
CONCLUSION
During the observation period, tapered implants
with an oxidized surface (TiUnite) proved to be a pre-
dictable foundation for supporting fixed prostheses
in compromised residual host bone or autogenous
grafted bone. From 1 year through 3 years after load-
ing, marginal bone levels were stable.A modified sur-
gical technique customized to the patient that mini-
mizes site diameter improves the likelihood of
success.
ACKNOWLEDGMENTS
The author thanks Reina Ramirez (Beverly Hills) and Malin
Bjursten Brailsford, PhD (Nobel Biocare, Göteborg, Sweden), for
their assistance with data compilation. Special thanks to Dr Rick
Sullivan for his help and wisdom.
REFERENCES
1. Goransson A,Wennerberg A.Bone formation at titanium
implants prepared with iso- and anisotropic surfaces of simi-
lar roughness:An in vivo study.Clin Implant Dent Relat Res
2005;7:17–23.
2. Kim YH,Koak JY,Chang IT,Wennerberg A,Heo SJ.A histomor-
phometric analysis of the effects of various surface treatment
methods on osseointegration.Int J Oral Maxillofac Implants
2003;18:349–356.
3. Kasemo B,Lausmaa J.Metal selection and surface characteris-
tics.In:Brånemark P-I,Zarb GA,Albrektsson T (eds).Tissue-
Integrated Prostheses:Osseointegration in Clinical Dentistry.
Chicago:Quintessence,1985:102.
4. Albrektsson T,Johansson C,Lundgren A,Sul Y-T,Gottlow J.
Experimental studies on oxidized implants.A histomorpho-
metrical analysis.Appl Osseointegration Res 2000;1:21–24.
5. Glauser R,Portmann M,Ruhstaller P,Lundgren A,Hammerle
CH,Gottlow J.Stability measurements of immediately loaded
machined and oxidized implants in the posterior maxilla.A
comparative study using resonance frequency analysis.Appl
Osseointegration Res 2001;2:27–29.
6. Henry P,Tan A,Allan B,Hall J,Johansson C.Removal torque
comparison of TiUnite and turned implants in the greyhound
dog mandible.Appl Osseointegration Res 2000;1:15–17.
7. Rocci A,Martignoni M,Burgos PM,Gottlow J,Sennerby L.His-
tology of retrieved immediately and early loaded oxidized
implants:Light microscopic observations after 5 to 9 months
of loading in the posterior mandible.Clin Implant Dent Relat
Res 2003;5(suppl 1):88–98.
8. Rocci A,Martignoni M,Sennerby L,Gottlow J.Immediate load-
ing of a Brånemark System implant with the TiUnite surface.
Histological evaluation after 9 months.Appl Osseointegration
Res 2002;3:25–28.
9. Rompen E,DaSilva D,Lundgren A,Gottlow J,Sennerby L.Sta-
bility measurements of a double-threaded titanium implant
design with turned or oxidized surface.Appl Osseointegration
Res 2000;1:18–20.
10. Wennerberg A,Albrektsson T,Andersson B,Krol JJ.A histomor-
phometric and removal torque study of screw-shaped tita-
nium implants with three different surface topographies.Clin
Oral Implants Res 1995;6:24–30.
11. Friberg B,Dahlin C,Widmark G,Ostman PO,Billstrom C.One-
year results of a prospective multicenter study on Brånemark
System implants with a TiUnite surface.Clin Implant Dent
Relat Res 2005;7(suppl 1):S70–S75.
12. O’Sullivan D,Sennerby L,Meredith N.Measurements compar-
ing the initial stability of five designs of dental implants.A
human cadaver study.Clin Implant Dent Relat Res 2000;2:
85–92.
13. O’Sullivan D,Sennerby L,Meredith N.Influence of implant
taper on the primary and secondary stability of osseointe-
grated titanium implants.Clin Oral Implant Res 2004;15:
474–480.
14. Abbou M.Primary stability and osseointegration:Preliminary
clinical results with a tapered diminishing-thread implant.
Pract Proced Aesthet Dent 2003;15:161–168.
15. Glauser R,Lundgren AK,Gottlow J,et al.Immediate occlusal
loading of Brånemark TiUnite implants placed predominantly
in soft bone:1-year results of a prospective clinical study.Clin
Implant Dent Relat Res 2003;5(suppl 1):47–56.
16. Östman P-O,Hellman M,Wendelhag I,Sennerby L.Resonance
frequency analysis measurements of implants at replacement
surgery.Int J Prosthodont 2006;19:77–83.
Bahat
325_Bahat.qxp 3/18/09 11:18 AM Page 333
All Rights Reserved

17. Friberg B,Jisander S,Widmark G,et al.One-year prospective
three-center study comparing the outcome of a“soft bone
implant”(prototype Mk IV) and the standard Brånemark
implant.Clin Implant Dent Relat Res 2003:71–77.
18. Lekholm U,Zarb G.Patient selection and preparation.In:
Brånemark P-I,Zarb G,Albrektsson T (eds).Tissue-Integrated
Prostheses.Chicago:Quintessence,1985:199–211.
19. Bahat O.Brånemark system implants in the posterior maxilla.
Clinical study of 660 implants followed for 5 to 12 years.Int J
Oral Maxillofac Implants 2000;15:646–653.
20. Bahat O,Handelsman M.Presurgical treatment planning and
surgical guidelines for dental implants.In:Wilson TG,Kornman
KS,Newman MG (eds).Advances in Periodontics.Chicago:
Quintessence,1992:323–340.
21. Sennerby L,Roos J.Surgical determinants of clinical success of
osseointegrated oral implants.A review of literature.Int J
Prosthodont 1998;11:414–416.
22. Schwartz-Arad D,Samet N,Samet N,Mamlider A.Smoking and
complications of endosseous dental implants.J Periodontol
2002;73:153–157.
23. Bahat O,Fontanesi RV,Preston J.Reconstruction of the hard
and soft tissues for optimal placement of osseointegrated
implants.Int J Periodontics Restorative Dent 1993;13:271–275.
24. Bahat O,Fontanesi RV.Efficacy of implant placement after
bone grafting for three-dimensional reconstruction of the
posterior jaw.Int J Periodontics Restorative Dent
2001;21:220–231.
25. Albrektsson T,Zarb GA,Worthington P,Eriksson RA.The long-
term efficacy of currently used dental implants.A review and
proposed criteria of success. Int J Oral Maxillofac Implants
1986;1:11–25.
26. Jaffin RA,Berman CL.The excessive loss of Brånemark fixtures
in type IV bone:A 5-year analysis.J Periodontol 1991;62:2–4.
27. Lekholm U,Wannfors K,Isaksson S,Adielsson B.Oral implants
in combination with bone grafts.A 3-year retrospective multi-
center study using the Brånemark implant system.Int J Oral
Maxillofac Surg 1999;28:181–187.
28. Wiltfang J,Schultze-Mosgau S,Nkenke E,Thorwarth M,
Neukam FW,Schlegel KA.Onlay augmentation versus sinus lift
procedure in the treatment of the severely resorbed maxilla:A
5-year comparative longitudinal study.Int J Oral Maxillofac
Surg 2005;34:885–889.
29. Rocci A,Martignoni M,Gottlow J.Immediate loading of Bråne-
mark System TiUnite and machined-surface implants in the
posterior mandible:A randomized open-ended clinical trial.
Clin Implant Dent Relat Res 2003;5(suppl 1):57–63.
30. Glauser R,Ree A,Lundgren A,Gottlow J,Hammerle CH,
Scharer P.Immediate occlusal loading of Brånemark implants
applied in various jawbone regions:A prospective 1-year clini-
cal study.Clin Implant Dent Relat Res 2001;3:204–213.
31. Albrektsson T.Is surgical skill more important for clinical suc-
cess than changes in implant hardware? Clin Implant Dent
Relat Res 2001;3:174–175.
32. Renouard F,Nisand D.Short implants in the severely resorbed
maxilla:A 2-year retrospective clinical study.Clin Implant Dent
Relat Res 2005;7(suppl 1):S104–S110.
33. O’Sullivan D,Sennerby L,Meredith N.Influence of implant
taper on the primary and secondary stability of osseointe-
grated titanium implants.Clin Oral Implants Res 2004;15:
474–480.
34. Brechter M,Nilson H,Lundgren S.Oxidized titanium implants
in reconstructive jaw surgery.Clin Implant Dent Relat Res
2005;7(suppl 1):S83–S87.
35. Glauser R,Ruhstaller P,Windisch S,et al.Immediate occlusal
loading of Brånemark System TiUnite implants placed pre-
dominantly in soft bone:4-year results of a prospective clini-
cal study.Clin Implant Dent Relat Res 2005;7(suppl 1):
S52–S59.
36. Callan DP,Hahn J,Hebel K,et al.Retrospective multicenter
study of an anodized,tapered,diminishing thread implant:
Success rate at exposure.Implant Dent 2000;9:329–336.
37. Kan JY,Rungcharassaeng K,Lozada J.Immediate placement
and provisionalization of maxillary anterior single implants:
1-year prospective study.Int J Oral Maxillofac Implants 2003;
18:31–39.
38. Albrektsson T,Brånemark P-I,Hansson H-A,Lindström J.
Osseointegrated titanium implants.Requirements for ensur-
ing a long-lasting direct bone-to-implant anchorage in man.
Acta Orthop Scand 1981;52:155–170.
39. Lekholm U,Gunne J,Henry P,et al.Survival of the Brånemark
implant in partially edentulous jaws.A 10-year prospecitve
multicenter study.Int J Oral Maxillofac Implants 1999;14:
639–645.
40. Nevins M,Langer B.The successful application of osseointe-
grated implants to the posterior jaw.A long-term retrospec-
tive study.Int J Oral Maxillofac Implants 1993;8:428–432.
Bahat
325_Bahat.qxp 3/18/09 11:18 AM Page 334
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