INTRODUCTION
The mandible occupies the most considerable bone portion of the facial
skeleton1. It plays a crucial role in
chewing, swallowing, phonation, speech, and smiling, providing shape, contour,
and vertical height of the lower third of the face2. It is the second most common site of fracture of the facial
bones3. Mandible fractures, if not
identified or treated correctly, can lead to severe sequelae1.
An ideal mandible reconstruction should be similar in structure, geometry, and
tissue in the absent area2. The fibular
osteocutaneous flap with osteotomies to mimic the mandibular shape was initially
described in 1989. Since then, the fibula-free flap with microsurgical
anastomosis has become an excellent weapon for mandibular reconstruction4. This flap has the advantage of
reconstructing large defects (up to 30 cm), a long vascular pedicle, and the
application of osteointegrated dental implants5,6.
With the assistance of computed tomography and the manufacture of models on 3D
printers, it is possible to obtain a better aesthetic and functional result of
the reconstructed organ, reducing the surgical time and its complications7.
Our objective is to describe a microsurgical reconstruction of the mandible with
osteocutaneous fibular flap, in a trauma patient, with the assistance of 3D
printing for pre and perioperative planning.
CASE REPORT
Patient, PGLO, 16 years old, smoker, admitted to the Risoleta Tolentino Neves
Hospital (HRTN) emergency after being found on a public road, victim of
aggression firearm projectile and blunt trauma in the face. Urgent tracheostomy
was performed due to airway obstruction.
The patient had an open fracture of the mandible, lower dental elements, and
several lacerations on the face. Computed tomography of the face showed a
comminuted fracture of mandibular bodies and branches, left maxilla with
rhinopharynx and oropharynx obstruction due to soft tissue edema (Figure 1).
Figure 1 - Admission tomography showing comminuted fracture of the
mandible.
Figure 1 - Admission tomography showing comminuted fracture of the
mandible.
The patient underwent debridement of devitalized tissues and repair of the
lacerations. New debridement was performed on the 20th postoperative day (POD),
with fracture fixation using a straight 4-hole plate on the left and a trans-gap
reconstruction plate with three screws on each side of the 2.0 system. Facial
vessels were identified and preserved. He was discharged on the 3rd POD of the
second surgical approach, with good evolution and adequate acceptance of a
liquid/pasty diet orally. He was referred to the outpatient clinic to schedule
mandibular reconstruction.
A new face tomography showed the reconstruction plaques joining the mandibular
bodies and branches, with a bone loss with an estimated distance of 8 cm between
the parts, thus indicating a reconstruction with fibrosurgical osteocutaneous
flap of the fibula (Figure 2).
Figure 2 - Preoperative tomography.
Figure 2 - Preoperative tomography.
A three-dimensional model of the mandible and plate was made using a polylactic
acid filament printer. With it, the surgical team could determine the distance
to be filled by the flap, define the side that the pedicle should be positioned
in, identify bone spicules to be removed, and program the holes’ positioning
for
fixing the plate. A fibula model was also created to program where and how
osteotomies would be performed on the procedure’s day. During the surgical
planning, the functions of each limb were defined (Figures 3 and 4).
Figure 3 - 3D reconstruction: patient’s mandible and fibula model.
Figure 3 - 3D reconstruction: patient’s mandible and fibula model.
Figure 4 - Models after training and surgical planning.
Figure 4 - Models after training and surgical planning.
Microsurgical reconstruction of the mandible with an osteocutaneous fibular flap
occurred five months after the trauma. The 10x5 cm skin island was located 6
cm
distal from the fibular head and 5 cm proximal to the lateral malleolus. The
perforators in the lateral intermuscular septum were identified. The long and
short fibular muscles, anterior intermuscular fascia, finger extensor, and
interosseous membrane were dissected, preserving 2-3mm of these structures
attached to the fibula; there was no injury to the skin perforators. The
gastrocnemius and soleus muscles were dissected, keeping the muscle layer
adhered to the bone. Proximal and distal osteotomies were performed in the
subperiosteal plane, identifying and ligating the fibular vessels distally. The
posterior tibial and flexor hallucis longus muscles were dissected, identified,
and linked to the fibular artery at its origin, accompanied by two fibular
veins. Osteotomies were performed in the subperiosteal plane using the 3D model
of the mandible and fibula as a guide. The models did not contact the patient.
The donor area was closed by plans with cutaneous synthesis and partial skin
grafting in an area of cutaneous island removal. The transverse cervicotomy
was performed, identifying the internal jugular and external carotid veins,
isolated the right facial artery, and vein isolated to perform the microsurgical
anastomosis. The reconstruction plate was dissected, and it was fixed with new
screws. The fibula was fixed to the reconstruction plate’s inner face with three
monocortical screws of 2.4x8.0 mm. Microsurgical anastomosis between fibular
vessels and right facial vessels was performed with separate points of prolene
8.0 with the assistance of magnifying glasses. The skin flap was fixed in the
cervical region for postoperative control of the flap (Figure 5).
The surgical times were simultaneous due to the subdivision of the teams. The
surgery lasted eight hours, and the time of total ischemia of the flap was three
hours.
The patient was kept in orotracheal intubation (OTI) for 48 hours at the ICU.
Mean arterial pressure was maintained above 70 mmHg, without the use of
vasoactive amines. Omeprazole 20mg, fixed-dose 8 mg between 8/8 hours for three
days. Antithrombotic prophylaxis with enoxaparin 40mg, with the introduction
of
ASA 100mg orally after the 3rd POD. Amoxicillin antibiotic therapy with
clavulanate 500mg + 125mg for ten days. The diet was initiated by nasoenteral
tube (NET) at the POI and progressed to the oral route (liquid/pasty) after
extubation. Walking with crutches started on the 9th postoperative day (POD)
and
without restriction after the 14th POD. The flap perfusion was evaluated with
a
serial clinical examination of the cutaneous island, in addition to an
evaluation with Eco-doppler showing good flow in the anastomosis. The patient
progressed well and was discharged on the 15th postoperative day.
He was followed up on an outpatient basis, maintaining a liquid/pasty diet for 45
days. Control tomography was performed at 40º POD, showing a good-looking flap
with no bone resorption signs (Figures 6
and 7).
Figure 6 - Control tomography - 40º POD.
Figure 6 - Control tomography - 40º POD.
Figure 7 - Pre and postoperative.
Figure 7 - Pre and postoperative.
The patient remains outpatient but did not undergo dental implants due to the
financial difficulty and slowness of the public health system’s process.
DISCUSSION
Currently, the technique of choice for mandibular reconstruction is made using
vascularized bone flaps.
The fibula-free flap is characterized by being an autogenous graft, segmented and
removed from the donor area. Its vascularization is preserved to nourish this
tissue when in the recipient bed, from its anastomosis with the recipient
region’s vascular system.
Reconstruction planning with prototyping and three-dimensional printers optimizes
microsurgical reconstruction with fibula autotransplantation8,9. The association of 3D technology showed several gains for better
surgical results and for the patient. There is a shorter surgical time,
increased perioperative efficiency, better accuracy in reconstruction in cases
of greater difficulty, better osteointegration, and occlusion after
implants10.
The planning cost depends on the piece’s size, difficulty processing the image,
printing time, and the material used. Nevertheless, because it is a pre-surgical
model (does not include guides or molds), it can be developed with printers and
non-specific software (non-medical), and this type of technology is more
accessible with a price ranging between R $ 900.00-R $ 1,500, 00.
The material used (PLA) requires a temperature of 185-205 ºC for printing, but
tests have not yet been carried out on whether the model would suffer
distortions during sterilization.
Validated sterility tests and sensitivity tests are also required to allow
risk-free contact for the patient. These are being carried out to improve the
model and allow greater versatility in its use.
CONCLUSION
The fibular osteocutaneous flap remains the gold standard for the reconstruction
of complex mandible defects.
In our experience, we realized the importance of the 3D model, especially in
surgical preparation, and the surgical time for flap osteotomy was
shortened.
We believe that three-dimensional printing is an essential weapon in
reconstructive surgery and should be used in complex cases intraoperatively and
as a surgical planning and discussion tool.
It is crucial the interaction of medical professionals and industry to popularize
and develop this type of product to bring gains to patients.
REFERENCES
1. Busuito MJ, Smith Junior DJ, Robson MC. Mandibular fractures in an
urban trauma center. J Trauma. 1986 Sep;26(9):826-9.
2. Neligan PC. Plastic surgery: craniofacial, head and neck surgery and
pediatric plastic surgery. Amsterdam: Elsevier; 2013.
3. Zachariades N, Papademetriou I, Rallis G. Mandibular fractures
treated by bone plating and intraosseous wiring. Rev Stomatol Chir Maxillofac.
1994;95(5):386-90.
4. Pellini R, Mercante G, Spriano G. Step-by-step mandibular
reconstruction with free fibula flap modelling. Acta Otorhinolaryngol Ital. 2012
Dez;32(6):405-9.
5. Mehta RP, Deschler DG. Mandibular reconstruction in 2004: an
analysis of different techniques. Curr Opin Otolaryngol Head Neck Surg. 2004
Ago;12(4):288-93.
6. Pereira MD, Marques AF, Brenda E, Castro M. Immediate reconstruction
of the central segment of the mandible using the masseter osteomuscular flap.
Plast Reconstr Surg. 1997 May;99(6):1749-54.
7. Jacek B, Maciej P, Tomasz P, Agata B, Kuczko W, Radoslaw W, et al.
3D printed models in mandibular reconstruction with free bone flaps. J Mater
Sci
Mater Med. 2018;29(3):23.
8. Braga-Silva J, Martins PDE, Román JA, Gehlen D. Reconstrução do
segmento ósseo mandibular: comportamento dos implantes ósseo-integrados nos
retalhos vascularizados de crista ilíaca e fíbula. Rev Bras Cir Plást.
2005;20(3):176-81.
9. Portinho PC, Jungblut CF, Bonilha LZ, Berteli JR, Collares MVM.
Reconstrução microcirúrgica de mandíbula com retalho livre de fíbula. Rev
AMRIGS. 2015 Jan/Mar;59(1):39-54.
10. Merick AF, Shaverien MV, Hanasono MM, Yu P, Largo RD, Villa MT, et
al. Using a second free fibula osteocutaneous flap after repeated mandibulectomy
is associated with low complicantion rate and acceptable functional outcomes.
Plast Reconstr Surg. 2017 Aug;140(2):381-9.
1. Hospital Risoleta Tolentino Neves, Plastic
Surgery, Belo Horizonte, MG, Brazil.
Corresponding author: Marcelo Martins
Casagrande, Rua Herculano de Freitas, 905 , Apto 1402, Independência,
Ribeirão Preto, SP, Brazil. Zip Code: 14076-300. E-mail:
marcelocasagrande1@gmail.com
Article received: July 04, 2019.
Article accepted: October 21, 2019.
Conflicts of interest: none
