A 33-year-old male patient was referred from another hospital with a 6-month history of a large right hemimandibular tumor. The patient had experienced progressive growth and referred fourth molar pain after extraction
Physical examination and orthopantomography showed a bone-dependent tumor of 5-6 cm in diameter, with involvement of both cortical bones, which extended from the region of the second premolar ipsilateral muscle to the middle of the mandibular ramus.
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A facial computed tomography (CT) was performed, which showed a mandibular tumor lesion of 5.5 × 4.8 × 3 cm. The right ramus was preserved, affecting the internal mandibular cortex and displacing the muscles and structures of the base of the major tongue.
A diagnostic biopsy was performed, resulting in myxoid lesion with reactive lymphoplasmacytic inflammatory component, with positivity for vimentin, CD138, Kappa, Lambda and partial positivity for actin.
Immunohistochemistry showed negativity for S-100, CD31 and CD68.
The diagnosis was mandibular odontogenic myxoma.
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Under general anesthesia and nasotracheal intubation, surgical excision of the lesion was performed with margins, using a combined intra- and extraoral approach, performing segmental hemimandibulectomy from the mandibular region to the mandibular arch ipsilateral.
The patient presented a dentate contralateral hemimandible.
Primary reconstruction was performed using free microvascularised fibular graft.
The maximum thickness of the fibula was 14 mm. The flap was preformed in situ, with the carving of the new hemimandible by means of a reconstruction bar modeled on the original mandible, and fixation mini-plate.
Vascular anastomosis was performed between the right peroneal and facial arteries, and between the concomitant veins peroneal and right thyrolingual-facial venous trunk.
The histological study of the piece was reported as mandibular odontogenic myxoma without involvement of surgical margins.
The postoperative course was uneventful.
After one year of the intervention, observing a height discrepancy between the fibula and the alveolar ridge of the contralateral hemimandible of 17 mm, it was decided to perform a vertical osteogenic distraction of the fibula.
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Distractor placement was performed under general anesthesia.
The fibular graft was exposed by means of an incision in the buccal oral mucosa, after which a subperitic dissection proceeded to adequately visualize the underlying lingual bone, giving extreme care to the periosteum.
The intraoral alveolar distractor (MODUS ARS 1.5; Medartis®, Basel, Switzerland) was placed on the buccal surface of the fibula to correctly design osteotomies.
Osteotomies were performed on the fibular buccal surface using an oscillating saw with saline irrigation.
A trapezium bony segment was obtained and the periosteum lingual remained intact.
Alveolar distractor was fixated on both sides of the horizontal osteotomy.
After verifying the perfect functioning of the distractor, it was arranged in its starting position, so that both bone fragments were in perfect apposition.
This is essential to initiate bone formation from the position of maximum contact between fragments and to achieve adequate hemostasis post-steotomy.
The vestibular incision was closed leaving part of the distractor through the incision, in order to facilitate its activation.
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Distractor activation was not performed during the latency period (10 days).
After this, the procedure was performed at a rate of 0.5 mm daily.
Vertical distraction of the peroneal bone and formation of bony trabeculae in the interface were observed at the end of stabilization in serial orthopantomised controls (obtained weekly).
17 mm of bone were obtained in 34 days, so that the fibular graft reached the same level as the contralateral alveolar ridge, with an optimal correction of the initial height discrepancy between them.
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The consolidation period lasted three months, during which the distractor was maintained at its initial fixation site.
Orthopantomography at three months confirmed an excellent ossification between the basilar and the distracted fragment.
Subsequently, in a second intervention, the distractor was removed using the same intraoral approach.
The quality of the newly formed bone, macroscopically verified, was excellent.
In the same intervention, three screwed titanium implants (3.75 × 15 mm) were placed in the distracted area.
Good primary stability was achieved in all implants.
The postoperative course was uneventful.
Prosthetic rehabilitation with implant-supported prostheses was successful after three months of osteosynthesis.
The aesthetic and functional results were satisfactory for both the patient and the surgeon after 18 months of follow-up.
