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Case Series
Ameloblastoma resection with
immediate rib reconstruction: addressing
the problem of mandibular angle and
central bone bulk
O Kenneth Johnson1 and Kapil Sharma2
Abstract
Several methods are available to treat mandibular tumours. This case series demonstrates the feasibility of resection and
immediate reconstruction with free rib graft in limited resource settings. Innovative technical modifications are described
to handle the problem of reconstruction of the angle of the mandible and to provide increased bone bulk in the centre of
the mandible. Early postoperative complications are few. Follow-up demonstrates good functional results.
Keywords
Africa, surgery
Introduction
The treatment of ameloblastoma has been problematic
because there have been high recurrence rates with con-
servative debridement but also fears of high complication
risks with aggressive surgical treatment and the perceived
need for complicated reconstructive techniques.
Therefore, several approaches have been attempted
including resection alone and resection with immediate
reconstruction. Previous studies have documented the
feasibility of different grafts and the difference of bone
durability as evidenced by radiologic criteria.
Clinical experience with treatment by tracheostomy
and immediate reconstruction with free rib graft forms
the planned programme for this study. The first patient
was followed for three years. Resorption of a significant
amount of bone was evident on radiography after 18
months but there was a very good functional result in
several categories: cosmesis; speech; deglutition; satisfac-
tory dietary intake; and airway control. There were clear
pathologic margins and, after three years, no evidence of
recurrence. Because clinical functional parameters con-
tinued to score well despite radiological changes, this
method was then investigated in a series of patients.
Methods
Our study was initiated to demonstrate the safety in
limited resource settings of such a regularly planned
treatment plan. Tracheostomy is performed at the
outset of the intervention and is followed by resection
and immediate reconstruction. A nasogastric tube is left
in situ afterwards to facilitate early feeding until post-
operative oedema resolves and the patient regains his
ability to swallow without much difficulty. Patients do
not normally require postoperative intensive care; they
are safely observed in the high dependency section of a
general surgical ward. Usually the tracheostomy tube
and nasogastric tube are removed by the tenth post-
operative day. Both short-term complications and
long-term functional results are carefully followed.
Our series of patients included those who presented
to our dental clinic with enlarged mandibular swelling
and where dental infection or trauma had been
excluded. Half of these patients had previous debride-
ment and had pathology results confirming ameloblas-
toma. Others had cystic lesions of the mandible
consistent with ameloblastoma and subsequent patho-
logic confirmation.
1Lecturer, Department of Surgery, College of Medicine U Malawi,
Blantyre, Malawi
2Dental Surgeon, Queen Elizabeth Central Hospital, Blantyre, Malawi
Corresponding author:
O Kenneth Johnson, College of Medicine University of Malawi, Box 360,
Blantyre, Malawi.
Email: okjohnsonsj@jesuits.net
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DOI: 10.1177/0049475517698869
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This work was carried out in Queen Elizabeth
Central Hospital (Bantyre, Malawi), Kamuzu Central
Hospital (Lilongwe, Malawi), and Mzuzu Central
Hospital (Mzuzu, Malawi). Records were kept as sur-
geon’s case files.
Results
A total of 25 patients were followed according to this
operative programme. The demographics showed a
nearly equal frequency of men and women with a
median age of 29 years. The tumours were large, in
the range of 5–20 cm, with a median length of 12 cm,
many of them involving the symphysis and the angle of
the mandible (Table 1).
We had no deaths and no crises related to airway
control. Local hospital staff resources decided whether
most patients were transferred simply to high depend-
ency units of surgical wards for postoperative monitor-
ing (QECH and KCH) or to intensive care (MCH).
There was one major complication with significant
intraoperative haemorrhage controlled by packing and
planned re-exploration 72 h later. This patient had a
free rib graft inserted at the second exploration with
good results.
Blood was transfused in 50% of patients because of
significant blood loss during the operation.
Minor complications included five patients who had
a small extrusion of bone graft in the first six months
after operation; these extruded pieces were< 1 cm2 in
size. Five other patients required removal of fixating
wires. One patient had significant absorption of the
bone graft and shortening of the reconstructed arch
without interference of speech or diet. Five patients
had purulent local infection over the bone graft which
resolved readily with local wound care and oral anti-
biotics (Table 2).
There were good functional results in terms of cosm-
esis, swallowing and speech in follow-up. There were no
long-term airway problems related to the tracheostomy
or to the reconstruction (Table 3).
Results were kept in the surgical log and outpatient
records.
Discussion
The first clinical consideration must be clarifying the
diagnosis. Extensive description of radiologic features
is found in reviews by Scholl.1 An extensive description
of pathologic features of dental tumours is found in a
review by Mullapudi.2 The rationale offered for recur-
rence after debridement-curettage is that the capsule is
incomplete and residual tumour finds room for recur-
rence within the bone marrow. Some recurrences can be
massive extending beyond 10 cm.3 Hence, many
authors advocate radical resection with margins of
0.5–1.0 cm.4
When a decision is made that curettage is unsatisfac-
tory and resection must be performed, additional con-
siderations come to the fore. The chief concern is to
protect the airway and then to restore speech, swallow-
ing and cosmesis. The reconstructive problems increase
progressively with larger resections involving the
midline, the angle of mandible and perhaps the entire
mandible. Wilson described the different pulls of muscle
groups distorting the residual fragments because of
Table 2. Complications.
Minor 5 patients required removal of fixation wire after
2 months postoperatively; no loss of soft tissue
contour
1 patient has significant absorption and shortening of
restored mandible; little interference speech and
diet
8 patients had minor extrusion of bone, less than
1 cm2
Major 1 patient had severe intraoperative haemorrhage
controlled by pack which was removed at 48 h;
free rib graft was placed without complication
except for minor bone extrusion after 2 months
Table 3. Long-term function.
Cosmesis Mouth opens over 3 cm in all patients
20/25 symmetrical mouth opening
Speech 7/25 clear speech
16/25 understandable
2/25 difficult
Swallowing All patients manage soft diet well; stable weight
15/25 able to chew with opposite side
10/25 report drooling with slight difficulty of
control
Airway 25 patients sleep without difficulty
25 patients report no difficulty from tracheos-
tomy wound
Table 1. Demographics.
Sex 9 women, 16 men
Age (years) 18–55 (median¼ 29)
Tumour size (cm) 6–20 (median¼ 12)
Half involve angle of mandible
Two-thirds involve midline
Follow-up (months) 1–15 (median¼ 9)
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attachments of the pterygoid and the hyoid muscles.5
Any defect> 5 cm warrants reconstruction. Free grafts
can be constructedfrom rib or iliac crest. Composite
grafts can be constructed from rib or fibula with mus-
culovascular attachments. When placed within the soft
tissue envelope, the residual muscles are stabilised but
strength for mastication may remain weak. The details
of different techniques are described elsewhere.
An important aspect of reconstruction is the man-
agement of the inferior alveolar nerve. Although others
have been able to preserve this nerve and even graft it
for reconstruction, so far we have not been able to
duplicate their good results.6 Because of the large size
of tumours in our series, the nerve has regularly been
sacrificed on the involved side.
Our distribution of demographic considerations
(gender, age) and location of tumour (premolar,
molar, angle of mandible) is consistent with other
reports. We have followed a system of standardising
treatment similar to that reported in Ghana.7
This series demonstrates that free rib grafts can be
used well beyond the generally accepted limits of a span
of 6–9 cm.8 Several modifications were found necessary
and these are detailed in the following description
(length, bulk, angle and fixation).
The first modification is the length of the span and
the remodelling required to shape the substituted bone
graft. The eighth rib is usually chosen for harvesting
(usually from the chest of the non-dominant arm) in
a subperiosteal manner; most often about 25 cm of rib
is obtained. On occasion, a second rib can be taken
without difficulty, even from the same side. The rib is
scored on the convex side to increase the angulation to
approximate the shape of the mandible (Figure 1).
A second modification is reconstructing the man-
dibular height and thickness when segmental resection
has been carried out. El-Sheikh described a method of
bundling a free rib graft to make a broader replace-
ment.9 This technique splits the entire rib and overlaps
the splits. Because of the large span required in our
patients, we have devised a simple technique of partially
thickening the graft by splitting a second length and
tying the additional graft over the primary rib graft.
This provides additional bulk especially in patients
where the primary rib graft appears too thin. As
El-Sheikh mentioned, the split rib incorporates readily
into the mandibular bed. We have not noted any extra
bone extrusion on follow-up (Figure 2).
A third modification is fashioning the rib graft to
reconstruct the angle of the mandible. This is done by
cutting a short segment to serve as the vertical pillar
and splicing the rib so as to overlap the split edges
(secured with wire). This preserves the ability to open
the mouth with adequate distance between the lips
(Figure 3).
The fourth modification relates to the fixation of the
graft. Routinely we fashion a well in the remaining
healthy mandible into which the graft can be wedged
and then held securely with wire. Where the condyle
has had to be resected, the residual capsule of the tem-
poromandibular joint is sutured with long-lasting
absorbable suture to the reconstructed rib graft. The
graft provides soft tissue support and there is enough
function to enable opening the mouth (Figure 1).
Rana has described two problems with the free rib
graft – absorption and graft failure.10 Of several pos-
sible sources of bone, a free rib graft was associated
with 64% resorption as determined from X-ray films
Figure 1. Free rib graft curved for central symphysis position,
placed in well of residual mandible.
Figure 2. Rib spliced with vertical pillar to reconstruct man-
dibular angle.
Johnson and Sharma 3
at one year. A small number of grafts failed because of
dehiscence of the wound, the need for debridement or
the recurrence of tumour. No major graft failures
occurred. Often a small piece of bone (< 1 cm2) may
extrude. In a rib graft of> 20 cm, this is usually of no
consequence. It should be emphasised that firm appos-
ition of soft tissue around the graft is important for
graft survival. Simple closure of the oral mucosa and
platysma muscle can leave space for seroma accumula-
tion and subsequent graft loss. We place several mat-
tress sutures in the remaining myelohyoid and
geniohyoid muscles and the soft tissue around the
submandibular gland. In our follow-up, we did not rou-
tinely measure radiolucency of residual graft but have
concentrated on the clinical assessment of function,
which remains satisfactory (Table 3).
Conclusion
This series documents the evaluation of several import-
ant clinical endpoints beyond mere radiological assess-
ment of the durability of the graft. Early consequences
of an ameloblastoma are progressive disability with
deglutition, denutrition, speech and control of secre-
tions as tumours progress. In a limited resource setting,
tracheostomy, mandibular resection and free rib graft
substitution is a safe and reliable method. This treat-
ment programme addresses the clinical problems well
and scores well both in patient satisfaction and clinician
assessment. The functional outcome is more important
than subsequent radiological appearances of the graft.
Acknowledgements
The authors thank the following for contributing to evalu-
ation and follow-up of patients: Mtisunge Nsewa, Clinical
Officer, Surgery Department and Dental Officers Gracian
Namowa, Joseph Mapwetechere and Chimwemwe Nyirenda
of Queen Elizabeth Central Hospital, Blantyre; Dental
Surgeon, Dr Jessie Mlotha and Dental Officers, Patrick
Mwale and Jimmy Mmela of Kamuzu Central Hospital,
Lilongwe; and Dental Officers Bwanakurzi Banda and
Cypriano Mlauzi at Mzuzu Central Hospital.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this
article.
Funding
The author(s) received no financial support for the research
and/or authorship of this article.
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Figure 3. Extra thickness provided by additional split rib
anchored by ligature.
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