Download Planning esthetic treatment after avulsion of maxillary incisors

Clinical
Planning esthetic treatment after
avulsion of maxillary incisors
Björn U Zachrisson1
Abstract
Background: When a young patient accidentally loses two neighboring maxillary incisors, the choice of treatment plan is
difficult. Although implant restorations are a popular option, they cannot be placed until skeletal growth is finished.
Furthermore, the use of two neighboring implant crowns represents a considerable challenge from an esthetic point of view.
This case report describes an innovative solution that combined autotransplantation of a developing premolar and
orthodontic space closure. Case Description: An 11-year-old girl sought treatment for avulsion of both her maxillary right
lateral incisor and her central incisor, which occurred as a result of a horseback-riding accident. Replantation by her general
dentist was unsuccessful. An oral surgeon transplanted the mandibular right second premolar to the injury site, and the
author moved the maxillary right quadrant mesially to close all spaces. The first premolar was intruded, and the canine
extruded, to provide normal marginal gingival contours. A prosthodontist, working with his dental technician, restored the
“abnormal” crowns with three porcelain veneers. The outcome was almost indistinguishable from a natural dentition.
Conclusions and Clinical Implications: When faced with treating severe traumatic injuries in growing patients, even
after avulsion of incisors, clinicians working in cooperation can optimize the outcome. A combination of transplantation
and space closure may represent the best treatment option, particularly when coupled with elements of esthetic dentistry.
The advantage of this approach is that a concomitant malocclusion can be treated simultaneously, and that the treatment
result is permanent. Interdisciplinary cooperation between orthodontists and other dentists, such as oral surgeons,
prosthodontists and general practitioners, appears to be of increasing importance in achieving high-quality treatment
results in such cases.
Key Words: Autotransplantation; traumatic injuries; avulsion; orthodontic space closure; esthetic dentistry; porcelain
veneers. JADA 2008;139(11):1484-1490.
One of the most challenging problems in dentistry is the
choice of treatment for replacement of one or more
maxillary incisors that have been lost as a result of
traumatic injuries. The problem of restoring esthetics and
function varies significantly according to the age of the
patient, the location of the traumatic injury and the
extent of the trauma. To produce an optimal treatment
result, it frequently is necessary to use the combined
efforts of an interdisciplinary team of experts,
representing pediatric dentistry, endodontics, oral
surgery, orthodontics, restorative dentistry and dental
technology. The skills of such a team sometimes can
recreate the beauty and function of the natural dentition
1
DDS, MSD, PhD. Professor II, Department of Orthodontics,
University of Oslo, Norway, and maintains a private orthodontic
practice in Oslo.
Address reprint requests to Dr. Zachrisson at Stortingsgaten 10,
0161 Oslo, Norway. E-mail [email protected]
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INTERNATIONAL DENTISTRY SA VOL. 12, NO. 2
even in cases of severe trauma.
Most traumatic dental injuries occur in childhood and
adolescence.1,2 Researchers have estimated that 70 to 90
percent of all traumatic dental injuries sustained in a
lifetime take place before the age of 19 years.2,3 Avulsion
(also known as exarticulation or total luxation) of teeth
affects mostly the maxillary central incisors and generally
occurs in children from 7 to 9 years of age, when the
permanent incisors are erupting.2,4,5 At this age, the
loosely structured periodontal ligament and low
mineralized bone that surround erupting teeth provide
only minimal resistance to an extrusive force.2 Most
frequently, avulsion involves a single tooth, but multiple
avulsions also occur.
Abbreviation Key
PLV: Porcelain laminate veneer.
Clinical
Replantation of an avulsed tooth is indicated when the
tooth is without obvious contamination and advanced
periodontal disease and the alveolar socket is sufficiently
intact to provide a seat for the exarticulated tooth.2
However, if a mature incisor is subjected to an extraoral
dry period of more than 60 minutes, the prognosis for a
successful outcome of replantation is remote.6,7
Complications may include replacement resorption
(ankylosis) or inflammatory resorption. The treatment of
replacement resorption may be either decoronation, in
cases in which the ankylosed tooth has progressive
infraclusion and in which residual alveolar growth is
anticipated, or preservation of the tooth in situ in the
interim before final treatment.2 Inflammatory resorption
should be treated with root canal therapy. The case
report included here describes the successful
interdisciplinary treatment of a difficult traumatic injury
case with avulsion of two neighboring maxillary incisors
in a young girl. The team included specialists in oral
surgery, orthodontics and prosthodontics.
Case Presentation
A girl aged 11 years, 5 months experienced a severe
traumatic dental injury in falling from a horse she was
riding, a situation similar to that described by Caglar and
Sandalli.8 The maxillary right lateral and central incisors
were avulsed (Figure 1), and her general dentist replanted
them about 60 minutes after the accident. Both teeth
had ankylosed a few weeks after the accident,
demonstrated a high percussion sound and were judged
by trauma experts (a pediatric dentist and an
endodontist) to have a hopeless longterm prognosis. It
was apparent that both incisors had to be extracted. The
patient had a Class II, Division 2 malocclusion with deep
overbite and moderate mandibular crowding in the
incisor area.
Having evaluated different treatment options to be
discussed below, I decided to attempt a combination of
autotransplantation and orthodontic space closure to
replace the two missing neighboring incisors. At that
initial visit, I referred the patient to an oral surgeon for
extraction of the maxillary left first premolar, which
would leave the first molar in distal relation to the
mandibular molar. I planned to eliminate the mandibular
crowding via extensive mesiodistal enamel contouring
from the right first premolar to the left first premolar (in
a technique described by Tuverson9,10 and Zachrisson and
colleagues11).
Two weeks after the patient’s initial consultation with
me, I referred the patient to an oral surgeon for the
Figure 1: Frontal facial view of 11-year-old patient who had lost both
the maxillary right lateral incisor and the maxillary right central incisor in
an accident.
transplantation of the mandibular right second premolar
to the anterior region. During the procedure, the oral
surgeon noticed evident ankylotic changes on both the
central incisor and the lateral incisor. He had to move the
alveolar preparation somewhat distally to include more
labial bone, and he had to tip it labially to prevent
premature contact against the mandibular incisors owing
to the deep overbite. There was a small apical perforation
to the nasal floor. The root development of the
autotransplanted premolar tooth had progressed slightly
more than optimally, but the apex was clearly wide open
(Figure 2). The oral surgeon placed the mandibular
premolar and sutured it in a high position (Figure 3).
I began the orthodontic treatment six months after the
operation, after a pediatric dentist had made a temporary
resin-based composite buildup on the natural premolar
crown (Figure 4). By then, the teeth in the maxillary right
quadrant had drifted mesially. Both canines and all
premolars had a marked lingual tilt (Figures 3 and 4),
resulting in a notably constricted smile. The treatment
objectives were these:
- close all spaces;
- obtain a normal high-low-high marginal gingival
contour for the three “new” anterior teeth in the
maxillary right side;
INTERNATIONAL DENTISTRY SA VOL. 12, NO. 2
55
Zachrisson
Figure 2: The developing mandibular right second premolar was
autotransplanted to the injury site. Note immature root development of
mandibular second premolars with open apex.
Figure 3: Autotransplanted premolar tooth in position. Note mesial drift
and excessive lingual crown inclination of maxillary canines and
premolars, constricting the smile.
the injury (Figures 7 and 8). The treatment result was
retained with a flexible gold-coated five-stranded .0215inch lingual retainer bonded to six teeth (Figure 9). The
final result was almost indistinguishable from a natural
dentition, with intact full gingival papillae and normal
contours (Figures 7, 8 and 10) and a full smile (Figure 10).
The result remained satisfactory and was stable at the
five-year follow-up in February 2008.
Replacement of Maxillary Teeth:
Treatment Options
Figure 4: After restoration with resin-based composite buildup on the
transplanted premolar, orthodontic treatment was begun with
superelastic leveling wire.
- widen the smile, mainly by adding marked lingual root
torque to the maxillary canines and posterior teeth, with
little lateral expansion;
- treat the deep bite with mandibular incisor intrusion
only, as the maxillary incisor display at rest was optimal;
- improve the crown inclination of the anterior teeth;
- resolve the mandibular crowding.
I bonded brackets to all teeth in both dental arches,
except for the maxillary first molars, which I banded and
provided with a custom-made transpalatal arch.12 After
an initial placement of a superelastic leveling arch wire
(Figure 4), I used rectangular stainless steel arch wires to
move and torque all teeth into proper axial inclinations
(Figure 5). I extruded the canine and intruded the first
premolar via bracket positioning and arch wire bends.
During the two-year, five-month treatment period, the
patient had another traumatic sports injury, resulting in a
horizontal crown fracture on the right canine (Figures 5
and 6). After removal of the orthodontic appliances
(Figure 6), a prosthodontist and his dental technician
made three ultrathin porcelain veneers for the location of
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If replantation is unsuccessful, and an avulsed tooth is
lost prematurely, several treatment possibilities exist:
- replacement of the lost incisor via autotransplantation
of a developing premolar (or another suitable donor
tooth);
- use of a single-tooth implant prosthesis;
- orthodontic closure of the space;
- after loss of multiple maxillary anterior teeth, treatment
with a combination of transplantation and orthodontic
space closure;
- maintenance of the space by means of a removable
denture with a single-tooth prosthesis.
These options will be discussed below.
Replacement of missing maxillary incisors with a
premolar transplant.
The surgical technique for tooth transplants requires
utmost care;13,14 the clinician can best learn it by
observing operations conducted by an experienced
transplant surgeon (J. Janakievski, DDS, MSD, e-mail
communication, September 2007). The optimal time for
autotransplantation of premolars to the maxillary anterior
region is when the root development has reached twothirds to threequarters of the expected final root
Zachrisson
Figure 5: Toward the end of orthodontic treatment, to level the gingival
margins, the clinician intruded the first premolar (to substitute the
canine). The canine used to replace the lateral incisor was extruded and
ground incisally. The patient experienced another traumatic injury that
resulted in a horizontal crown fracture on the right canine.
Figure 6: Orthodontic treatment result. Note upright canines and
posterior teeth to broaden the smile (compare with Figure 3). The deep
bite and midline are slightly overcorrected. The right canine crown
fracture is apparent.
Figure 7: Three porcelain veneers are placed on the “new” canine, lateral
incisor and central incisor.
Figure 8: Higher magnification of the three teeth provided with veneers.
Note natural tooth morphology and normal gingival condition.
length.13,15 The prognosis for complete periodontal
healing at this stage of root development is better than
90 percent.13,15 After transplantation, root growth
continues and the teeth maintain their capacity for
functional adaptation. Endodontic treatment usually is
not necessary. Patients suited for autotransplantation of
premolars to the maxillary anterior region are about 9 to
12 years of age, which corresponds with the period when
most serious traumatic dental injuries occur in children. It
is remarkable that tooth transplants have inherent
potential for alveolar bone growth16-20 and reestablishment of a normal alveolar process (Figures 3-8).
were high – 90 percent and 79 percent, respectively.
Thus, transplantation of teeth with partly formed roots
compares favorably in a long-term perspective with other
treatment modalities for substituting missing teeth.
Long-term survival and success rate.
Czochrowska and colleagues20 evaluated the longterm
outcome of 33 transplanted premolars for 17 to 41 years
after their transplantation (mean, 26.4 years). Both the
survival rate (teeth still present at the examination) and
the success rate (teeth fulfilling defined success criteria)
Orthodontic and restorative treatment for
transplanted premolars.
Because the root of a transplanted premolar continues to
develop and a normal periodontal ligament is reestablished, such teeth can be moved orthodontically like
any other tooth that has erupted into occlusion.15-20
Premolar crowns (Figure 3) can be reshaped to
resemble incisor morphology with a porcelain laminate
veneer (PLV)21 (Figures 7 and 8). The two main reasons to
avoid placing cemented crowns in adolescents – that the
large pulp chambers limit preparation and that the
gingival retraction across time could lead to unesthetic
root display – are not valid for minimally invasive PLVs.
The reflection of light will not be stopped by an enamelINTERNATIONAL DENTISTRY SA VOL. 12, NO. 2
55
Zachrisson
Figure 9: The treatment result was maintained with an .0215-inch goldcoated wire retainer bonded lingually to six teeth.
bonded veneer, and any later root exposure will display a
normal color without darkening.21 In a 2000 study, my
research colleagues and I17 evaluated 45 premolars
transplanted to the maxillary incisor region, after
restoration, with a mean observation period of four
years. The clinical variables for transplants did not differ
from those of the natural incisors, except for some
increased mobility and more plaque in a few
autotransplanted premolars.17,18 Notably, the interdental
gingival papillae adjacent to all transplanted teeth were
normal or slightly hyperplastic, and we found no
interdental gingival recession (“black triangles”).
Esthetic outcome and patient satisfaction.
In a 2002 study, my research colleagues and I18 compared
22 transplanted premolars reshaped to incisor
morphology with their natural, contralateral incisors.
Most transplanted teeth matched the contralateral
incisors, and a majority of patients were satisfied with the
appearance of the transplant. However, the color and the
crown width along the gingival margin were scored as
different from those of the natural incisor when the
restorations were made with resin-based composite.
Thus, because of limited width in the gingival area, PLVs
rather than composite buildups are the preferable
alternative for restoration of the premolar crowns.
Conclusion. Premolar autotransplantation represents an
attractive, and probably the best, solution to difficult
treatment planning problems when a young patient,
such as the one described in this article, loses a maxillary
incisor to trauma (Figures 7-10). The transplanted tooth
represents a normal root with a normal periodontal
membrane, and it can be moved orthodontically like any
other natural tooth. The “abnormal” crown should be
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INTERNATIONAL DENTISTRY SA VOL. 12, NO. 2
restored with a porcelain veneer. Transplantation
represents a biological approach in which the
transplanted tooth germ retains the potential to induce
alveolar bone growth.
Replacement of missing maxillary incisors with
single-tooth implants.
Within the last two decades, the use of osseointegrated
implants to replace missing maxillary central and lateral
incisors has become a common treatment solution for
patients 20 years and older. Experience gained to date
with single-tooth implants is favorable, with survival rates
of about 90 percent after 10 years in multicenter
studies.22 However, filling an anterior space with an
implant-supported porcelain crown is a major challenge
from both esthetic and functional aspects. Clinical
success depends not only on persisting osseointegration
but also on harmonious integration of the crown in the
dental arch.22 An implant crown placed in a young adult
should have an expected life span of 50 or more years.
Research indicates that the esthetic result for single
implants in the esthetic zone sometimes is suboptimal,
even in adults and elderly patients.22-25
Esthetic problems with implant crowns.
There are several potential esthetic problems associated
with the long-term use of implant-supported crowns,
including age changes in tooth position,26 leading to
progressive infraocclusion of the implant crown and
uneven marginal gingival contours (this may particularly
create an esthetic problem in patients showing a great
deal of tooth eruption—high-angle face types and open
bite tendency—and in “gummy” smiles); 22-25 labial alveolar
bone loss and gingival dark discoloration; 22,27 lack of
gingival papilla fill, particularly on the distal side;28 and
Zachrisson
Figure 10: The final result, with the patient showing a full smile.
gingival recession occurring for different reasons with
increasing age, resulting in dark margins along porcelain
crowns.26
But the major disadvantage of planning esthetic
treatment with implants in adolescents is, of course, that
the young patient has to wait until completion of facial
growth before receiving the final prostheses. During the
interim period, which may last several years, the patient
has to wear either a removable retainer or a fixed
resinbonded prosthesis that may be prone to fracture.29
Conclusion. The single-tooth implant may be a useful
treatment option in adults when maxillary incisors have
been lost accidentally or are missing congenitally. Implants
normally should not be placed until the skeletal growth is
completed. Independent studies indicated that progressive
infraclusion over time (even in mature adults) of single
implants replacing maxillary incisors sometimes may make
the replacement crown esthetically suboptimal.22-25
Extended long-term evaluations are needed.
Replacement of missing maxillary lateral incisors
with canines during orthodontic space closure.
When a maxillary canine is moved mesially to substitute
for a missing lateral incisor, and the first premolar is
used in place of the canine, esthetic and functional
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INTERNATIONAL DENTISTRY SA VOL. 12, NO. 2
concerns may arise. However, when careful
orthodontic treatment is combined with clinical
techniques adapted from esthetic dentistry, the
outcome with space closure can be satisfying and
almost indistinguishable from a natural dentition.30-34
Such methods may include the following:32,34
- individualized extrusion and intrusion during mesial
movement of the canine and first premolar, respectively,
to obtain an optimum level for the marginal gingival
contours of the anterior teeth;
- careful correction of the crown torque of a mesially
relocated canine to mirror the optimal crown torque of
a lateral incisor, along with the provision of optimal
torque for the mesially relocated first and second
premolars;
- esthetic recontouring of a mesially relocated canine to a
more ideal lateral incisor shape and size with a
combination of grinding and resin buildups or porcelain
veneers;
- increasing the width and length of mesialized and
intruded first premolars with buildups or veneers to
achieve optimal esthetics and functional occlusion;
- intentional vital bleaching of a yellowish canine that has
been moved mesially into the lateral incisor position;
- using simple minor surgical procedures to achieve
localized clinical crown lengthening.
Zachrisson
Long-term periodontal and occlusal studies regarding
congenitally missing lateral incisors have shown that
space closure with premolar substitution for canines may
lead to an acceptable functional relationship, with
modified group function on the working side.35 Another
study (mean, seven years after treatment) concluded that
orthodontic space closure produced results that were
well-accepted
by
patients,
did
not
impair
temporomandibular joint function and encouraged
periodontal health in comparison with prosthetic
replacement.36
Replacement after loss of multiple maxillary anterior
teeth.
Multiple loss of anterior teeth represents a significant
increase in the number of esthetic problems. This is
caused primarily by the associated alveolar bone loss,
which may require both horizontal and vertical bone
augmentation.2 Fortunately,
in
children,
the
autotransplantation of developing premolars may induce
alveolar bone growth and thus make it possible to restore
the dental arch form using a combination of
transplantation and orthodontic space closure after
severe accidents involving the loss of several maxillary
incisors.21,37
In adults, a significant esthetic problem will occur
when two implants are placed next to each other. In
these instances, it generally is not possible to create a
satisfactory gingival papilla between the two
implants.38,39 One treatment principle to reduce this
problem may be to combine orthodontic space closure
and one implant.39
Conclusion. When two or more maxillary incisors are lost
in young patients, tooth transplantation should be the
treatment of choice. This treatment has the potential to
restore both the dentition and the alveolar bone.
Maintaining the space by means of a removable
denture with a single-tooth prosthesis.
The basic problem in using a removable denture with a
tooth (or a resin-bonded bridge) to replace a lost
maxillary incisor is, of course, the progressive increase of
alveolar bone resorption that takes place at the same
time as the continued eruption of the neighboring teeth.
Conclusion
A combination of premolar transplantation, orthodontic
space closure and porcelain laminate veneers may be the
best treatment option after severe traumatic dental
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INTERNATIONAL DENTISTRY SA VOL. 12, NO. 2
injuries with avulsion of one or more incisors in growing
patients. Any concomitant malocclusion can be treated at
the same time, and the treatment outcome is permanent
(Figures 7-10).
Disclosure
The author did not report any disclosures.
The author gratefully acknowledges the skillful efforts of
Dr. Bjørn Album, oral surgeon, Oslo, Norway, during the
transplant operation. The author also thanks Dr. Sverker
Toreskog, prosthodontist, Göteborg, Sweden, and Mr.
Claes Myrin, master dental technician, Göteborg,
Sweden, for making the porcelain veneers.
Zachrisson BU. Planning esthetic treatment after
avulsion of maxillary incisors. JADA 2008;139(11):1484-90.
Copyright © 2008 American Dental Association. All
rights reserved. Reprinted by permission.
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