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CLINICAL APPLICATION
2THE EUROPEAN JOURNAL OF ESTHETIC DENTISTRY
VOLUME 7 • NUMBER 1 • SPRING 2012
Soft Tissues Remodeling Technique
as a Non-Invasive Alternative to
Second Implant Surgery
Xavier Vela, MD, DDS
Private Practice in Barcelona, Spain
Víctor Méndez, DDS
Private Practice in Barcelona and Madrid, Spain
Xavier Rodríguez, MD, PhD
Private Practice in Barcelona and Madrid, Spain
Maribel Segalà, MD, DDS
Private Practice in Barcelona, Spain
Jaime A. Gil, MD, DDS, PhD
Chairman of Prosthodontic, University of The Basque Country,
Bilbao, Spain
Correspondance to: Dr Xavier Vela
Barcelona Osseointegration Research Group, Sant Martí 43-47, Sant Celoni 08470, Barcelona, Spain;
Tel: +34-938-675822; Fax: +34-938-674419; E-mail: [email protected]
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VOLUME 7 • NUMBER 1 • SPRING 2012
Abstract
It is currently accepted that success in
implant-supported restorations is based
not only on osseointegration, but also on
achieving the esthetic outcome of natu-
ral teeth and healthy soft tissues. The so-
called “pink esthetics” has become the
main challenge in the implant-supported
rehabilitations in the anterior area. This is
especially difficult in the cases with two
adjacent implants.
Two components affect the final peri-
implant gingiva: a correct bone support,
and a sufficient quantity and quality of
soft tissues. Several papers have em-
phasized the need to regenerate and
preserve the bone after extractions, or
after the exposure of the implants to the
oral environment. The classical implanta-
tion protocol entails entering the working
area several times and always involves
the surgical manipulation of peri-implant
tissues. Careful surgical handling of the
soft tissues when exposing the implants
and placing the healing abutments (sec-
ond surgery) helps the clinician to obtain
the best possible results, but even so
there is a loss of volume of the tissues
as they become weaker and more rigid
after each procedure.
The present study proposes a new
protocol that includes the connective
tissue graft placement and the soft tis-
sues remodeling technique, which is
based on the use of the ovoid pontics.
This technique may help to minimize the
logical scar reaction after the second
surgery and to improve the final emer-
gence profile.
(Eur J Esthet Dent 2012;7:xxx–xxx)
3THE EUROPEAN JOURNAL OF ESTHETIC DENTISTRY
VOLUME 7 • NUMBER 1 • SPRING 2012
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Introduction
It is currently accepted that success in
implant-supported restorations is based
not only on osseointegration, but also on
achieving the esthetic outcome of natu-
ral teeth and healthy soft tissues.
Over recent years, a large number of
papers have focused on the so-called
“pink esthetic”, and the majority of au-
thors agree that it is difficult to ensure
that the gingiva around the implant-
supported restorations has the same
thickness and height as is found around
natural teeth. This is especially difficult
in the interimplant papilla, which is now
one of the greatest challenges in esthet-
ic implant dentistry.1,2
Several papers have emphasized the
need to preserve the bone after extrac-
tions or to regenerate the lost bone be-
fore or during the implant-placement.
The bone not only fixes the implant but
also plays an esthetic role, giving sup-
port to the soft tissues.3
Nowadays the classical protocol pro-
posed by Branemark4 continues to be
useful and predictable. Three surgical
steps compose this protocol: the extrac-
tions, the implant placement and some
months later, the second surgery, when
the implant becomes exposed to the
oral environment.
This second surgery usually means
peri-implant bone resorption because of
the biologic width establishment5,6 and
also a soft tissue scar reaction, which is
especially important in a case with two
adjacent implants, taking into considera-
tion the limitations to obtain an adequate
height of the interimplant papilla.7
The present study proposes the gin-
gival remodeling technique as a way to
obtain a predictable interimplant papilla
and avoid a traumatic second surgery.
Gingival remodeling
To achieve a good prosthetic emer-
gence profile, several of the surgical
techniques that have been described
can be used in the different stages of an
implant treatment.8–11
Careful surgical handling of the soft
tissues when exposing the implants and
placing the healing abutments (second
surgery), helps with obtaining the best
possible results.12 But even so, there is a
loss of volume of the tissues as they be-
come weaker and more rigid after each
procedure.2
To prevent surgery causing side ef-
fects in the soft tissues, the present study
proposes a new protocol that includes
the technique of soft tissue remodeling,
minimizing the logical scar reaction after
the second surgery and the loss of qual-
ity and quantity of the inter-implant soft
tissues. This new protocol involves two
steps:
1st stage – the connective tissue graft placement
The function of the epithelium is to pro-
tect the internal medium from the ex-
ternal contaminated environment. The
connective tissue gives support, filling,
nutrition, and defense. To ensure these
functions, the connective tissue is com-
posed of several collagen fibbers, posi-
tioned in different directions.13
The first two functions are the ones that
will help us most in improving our esthetic
outcome, conditioning not only the gingi-
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Fig 1 Adding compomers to the temporary tooth-
supported bridge. (a) First week (b) Second week
(c) Third week (d) Fourth week
val volume but also the response of this
tissue to prosthetic manipulations and
even preventing chromatic alterations.14
As it is possible to adapt and mold
this component to the shape of the tem-
porary prostheses, the connective tis-
sue will determine the so-called pink
esthetics of the implant supported re-
habilitations, which plays an important
role in the final prosthetic result. For this
reason, especially in the esthetic zone, it
is essential to achieve a good thickness
of moldable connective tissue.
Several techniques have been pro-
posed to increase the connective tissue
thickness, depending on the protocol,
the placement of the graft when simul-
taneously seating the implants in the ini-
tial surgical stage; and more recently the
type of incision, the location of the donor
site, the volume susceptible to earn.15-17
One of the most used procedures is
the subepithelial connective tissue graft
technique, proposed by Langer and Ca-
lagna.15 The soft tissue graft is placed at
a different surgical stage to the implant
site, because in the esthetic zone it is
usual to augment the bone when plac-
ing the implants. This implies the use
of biomaterials and resorbable mem-
branes, so reducing the vascularization
of the recipient site and increasing the
risk of necrosis.18
2nd stage: the modeling of the augmented soft tissues through the ovate pontics of the tempo-rary prostheses
The use of ovate pontics has been wide-
ly described. Pressure is put on the soft
tissues to obtain the ideal emergence
profile.19-23
The present technique takes this con-
cept further, finishing when the ovate
pontic makes contact with the cover
screw. Then, it can be replaced by a
healing abutment, thus avoiding a trau-
matic second surgery. This can be done
using temporary prosthesis.24,25
There are two possible options:
�� If it has been decided to use neigh-
boring teeth as part of the restorative
treatment, then temporary tooth-sup-
ported bridges will be used (Fig 1).
�� If neighboring teeth will not be in-
volved in the treatment, a removable
partial skeletal prosthesis is suggest-
ed (Fig 2), which will guarantee pros-
thetic stability. The prosthesis can
be the same as the one the patient
has been wearing over the previous
months since the exodontia, and
will subsequently be used to help
achieve an optimal esthetic result.
a
c
b
d
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This type of partial prosthesis is less
comfortable for the patient, but has
the advantage of easy access and
manipulation, and does not involve
aggression to neighboring teeth.
The pontic should be placed at a slight
distance from the gingiva during the first
few weeks so it will not exert pressure on
the grafts, which could compromise their
vascularization and cause necrosis.
The soft tissue remodeling starts one
month after the soft tissue graft place-
ment. Nonetheless, fluoroangiographic
studies by Busschop et al show that
grafts are fully revascularized after 15
days; therefore, it could be possible to
start gingival remodeling even sooner.26
The ovate pontics volume of the tem-
porary prostheses gradually increases
week after week, adding an easy-to-
handle light-cured biocompatible mate-
rial: compomers. The compomers have
shown their biocompatibility in class V
restorations, where the compomer is in
contact with the gingiva.
The changes of the shape and the en-
largement of the volume, lead the ovate
pontics to mold the gingival, gradually
achieving the ideal emergence profile
(Figs 3 to 5). The pressure on the soft
tissues must not be harmful, because
the epithelium must preserve its integrity
and the connective tissue has to recover
its normal vascularization after only a few
minutes of ischemia. For this reason the
increased volume should not be greater
than 1–1.5 mm per week.
The shape and volume of the ovate
pontics must be adapted to the needs of
the each particular case, and the weekly
changes of the temporary prostheses
have to be adapted to the evolution of
the soft tissues. This means that there
is not a pattern that marks the design
of this technique. The surgical guide
used for the correct positioning of the
implants can help to guide the change
in the shape and volume of the ovate
pontics in order to reach the implants.
The objective of this technique is not
only to achieve the ideal emergence pro-
file but also to avoid a traumatic second
surgery. This means that the process
should be followed for four or five weeks
until the cover screws are exposed.
At the end of the process, only a thin
epithelium layer is covering the cover
Fig 2 (a) Adding compomers to the removable partial skeletal prostheses. (b) First week (c) Second
week (d) Third week (e) Fourth week
ba c d e
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Fig 3 Soft tissues remodeling technique. Clinical case with removable temporary prostheses. (a) Initial
situation (b) Stage 1. Immediate implant placement after extraction before hard and soft tissues grafts. (c) Stage 2. Two months after implant placement, here starts the soft tissue remodeling technique. (d) One
week later (e) Two weeks later (f) Three weeks later. Notice the implant transparency in the occlusal view
(right). (g) Four weeks later: non-invasive second stage, impression copying test. (h–i) One year after the
prosthetic placement and Rx.
a b
c
e
g
d
f
h
i
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Fig 4 Soft tissues remodeling technique. Clinical case with removable temporary prostheses. (a–b) Initial situation (c) Stage 1 – delayed implant placement and hard and soft tissue grafts. (d) Stage 2 – six
months later. Here starts the soft tissue remodeling technique. (e) One week later (f) Two weeks later (g) Three weeks later (h–i) Four weeks later. Non-invasive second stage. (j–k) One year after the prosthetic
placement.
a b
c
e
g
d
f
h
i
k
j
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Fig 5 Soft tissues remodeling technique. (a) Clinical case with fixed temporary prostheses. (b) Stage
1 – implant placement with hard and soft tissue grafts. (c) Fixed temporary prostheses. (d) Stage 2 – six
months later. The soft tissue remodeling technique begins. (e) One week later (f) Two weeks later (g) Three weeks later (h) Four weeks later – the non-invasive second stage. (i–j) Two years after the prosthetic
placement.
a b
c
e
g
d
f
h
j
i
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screw. A screwdriver is usually enough
to pierce the epithelium, remove the
cover screw and place the healing abut-
ment or the impression coping.
This two-stages technique avoids the
second surgery, which would possibly
damage the interimplant papilla, prob-
ably the most sensitive area, and deter-
mines the final outcome in a case with
adjacent implants.
Discussion
According to literature, the most difficult
area to obtain an adequate height of the
papilla is the interimplant space. Some
papers agree that the average height of
the interimplant papilla, measured from
the contact point to the interimplant
bone peak, is 3.5 mm compared to the
6.5 mm found between natural teeth.7
Therefore, independently of bone lev-
el, the interimplant papilla always has
a lower height, and this conditions the
esthetic outcome when comparing it to
the height of the soft tissues between
natural teeth.7,27,28
With this in mind, it seems of para-
mount importance to maintain the inter-
implant bone peak, trying to minimize
the peri-implant bone resorption after
expositing the implants to the oral envi-
ronment. The new concept of platform
switching has led to a considerable re-
duction in peri-implant bone loss with
average bone loss values of 0.65 mm
on the vertical and horizontal axis.29–32
The exposure of the implants to the
oral environment has been related to
peri-implant bone resorption and the
soft tissues retraction. Some authors
have described the soft tissues around
the implant abutments as a scar with
abundant collagen fibers and few cells.
Berglundh et al33 observed that the vas-
cular supply in the free gingiva comes
mainly from the supraperiosteal vessels
and the vessels of the periodontal liga-
ment (Figs 3–5).
However the vascular system in the
peri-implant mucosa originates solely in
the large supraperiosteal blood vessel
outside the alveolar flange. This vessel
branches to form a plexus of capillaries
and venules under the oral epithelium
and the junctional epithelium. The authors
reported that there is no vascular plexus
near the implant to compensate for the
lack of the periodontal ligament plexus.
Lindhe et al reported a diminished de-
fensive capacity of the peri-implant gin-
giva as compared to the periodontal gin-
giva.34 This compromised situation was
largely explained by the vascular deficit
in the supra-alveolar connective tissue.
Thus, there is a considerable limitation
of the peri-implant soft tissues healing
in front of an aggression, eg, such as
a surgical aggression. For this reason
it seems interesting to avoid a second
surgery, especially when there are two
adjacent implants in the esthetic zone.
The surgical treatment to expose the
implants implies an open wound. The
second intention healing causes the
contraction of the tissues to reduce the
gap between the abutment and the mu-
cosa and the new epithelization guaran-
tees the closure of the exposed tissues.
These tissue reactions are particularly
important when they affect the inter-
implant tissues between two adjacent
implants, causing an important loss of
quantity and quality of the inter-implant
papilla.
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The present technique described in
this article is able to reduce the scar re-
action of the peri-implant tissues. This
technique is based on the use of the
ovate pontics. The ovate pontics modify
the shape of the residual ridge by grad-
ual pressure over the gingival tissue,
improving esthetics and giving a natu-
ral look to our restorations.35 A gradual,
controlled hyperpressure can transform
an unfavorable tissue configuration. This
allowed a more natural, functional resto-
ration. There is also a possibility of clos-
ing undesirable ‘black holes’ through pa-
pilla ‘formation’, by pressuring the tissue.
In the past, some believed that a pres-
sure over the residual ridge resulted in
an inflammatory process. Recently pub-
lished data have shown that a well con-
trolled hyperpressure, applied with a
convex and highly polished pontic, asso-
ciated with rigid plaque control, resulted
in only a thinning of the epithelium with no
inflammation.35 Tripodakis and Constan-
tinides36 showed that increased pres-
sure from smooth, polished, and glazed
convex pontics in patients with excellent
plaque control did not induce inflamma-
tion in the adjacent tissues. Tolboe et al37
demonstrated that the mucosa under
ovate pontics remained healthy, irrespec-
tive of the pontic material used, when
dental floss was used regularly. Zitzmann
et al38 performed a histological evaluation
of the alveolar ridge mucosa adjacent to
an ovate pontic after 1 year, showing that
these sites were not associated with overt
clinical signs of inflammation.
The ovate pontics move the connective
tissue and the epithelium progressively
without damaging them. The pressure
does not break the epithelial barrier but
it moves it onto the cover screw. The final
healing after removing the cover screw
and placing the healing abutments has
only to cover a minimum distance to en-
sure the biologic width establishment. A
better vascularization of the peri-implant
soft tissues and less scar reactions could
be the consequence. Few changes oc-
cur after the exposure of the implants and
the gingival architecture remains similar.
A minimum thickness of 3 to 5 mm of
soft tissue is required to improve the final
outcome.35 This measurement is record-
ed from the gingival crest to the alveolar
ridge. Optimal results are realized when
pressure is applied to thick tissues, al-
though caution is needed regarding
its resilience.35 For this reason, soft tis-
sue augmentation through subepithelial
connective tissue grafts is commonly
required before starting the soft tissue
remodeling technique.
Conclusions
The use of this technique can reduce the
scar reaction of the soft tissues, which is
usually caused by the second surgery to
expose the implants to the oral environ-
ment. This effect is especially important
in the interimplant papilla of adjacent im-
plants in the anterior area.
The pressure of the ovate pontics
move the soft tissue, thus achieving an
optimum emergence profile and main-
tain the integrity of contact between the
epithelial barrier and the cover screw,
so avoiding a traumatic second surgery.
This study concludes that the soft
tissue remodeling technique based on
the use of the ovate pontics can help to
improve the esthetic outcome, and the
predictability of these cases.
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