About Dr. Zhang Zhiyuan
Dr. Zhang Zhiyuan is Director of Oral and Maxillofacial Surgery at Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine — China's top-ranked institution for oral and maxillofacial care. He specialises in jaw tumour resection, salivary gland disease, and complex facial reconstructive surgery, with particular expertise in digital-guided oncological resection and free fibula osteocutaneous flap reconstruction for large mandibular defects. Dr. Zhang's practice is defined by the philosophy that oncological cure and functional-aesthetic restoration are not competing goals — they are simultaneous obligations. His team at Shanghai Ninth Hospital has pioneered the integration of virtual surgical planning, 3D-printed cutting guides, and immediate implant-supported dental rehabilitation into a single operative workflow, achieving facial symmetry and masticatory function outcomes that were not possible with conventional techniques.
Case Overview
Ms. Claire Dubois, a 28-year-old French graphic designer based in Shanghai with exceptionally high aesthetic expectations, presented with a two-year history of right lower facial swelling and tooth mobility, and recent onset of right lower lip numbness indicating inferior alveolar nerve involvement. She had undergone curettage at an external institution two years prior; the tumour had recurred. CBCT and contrast-enhanced CT confirmed a massive solid/multicystic ameloblastoma of the right mandibular body and ramus — 10 cm in extent — with soap-bubble multilocularity and root resorption. Dr. Zhang Zhiyuan designed a fully digital operative workflow: virtual surgical planning with Mimics software, 3D-printed osteotomy guides with 1 cm oncological margins, simultaneous free fibula harvest, double-barrel fibula reconstruction to restore mandibular vertical height, pre-bent patient-specific titanium plate fixation, microsurgical vascular anastomosis, and immediate implant placement. Operative time was 6.5 hours; ischaemia time 45 minutes; blood loss 300 mL. At two-year follow-up, there is no tumour recurrence, osseointegration is complete, final ceramic dental restoration has been placed, facial symmetry is excellent, and the patient has returned to full-time design work.
Patient Background
- Name / Nationality: Ms. Claire Dubois (pseudonym) — French; graphic designer based in Shanghai
- Age / Sex: 28-year-old female
- Chief Complaint: Right lower facial swelling and tooth mobility for 2 years; right lower lip numbness (recent onset)
- Surgical History: Curettage at external institution 2 years prior; tumour recurred — curettage is inadequate for ameloblastoma and the primary cause of recurrence
- Examination: Right mandibular body expansion; firm; malocclusion; right mental nerve hypoaesthesia
Imaging and Digital Surgical Planning
CBCT and Contrast-Enhanced CT
- Tumour morphology: Multilocular radiolucency with soap-bubble appearance; root resorption of adjacent teeth
- Extent: Right mandibular body and ramus — 10 cm from second premolar to sigmoid notch
- Critical anatomy: Inferior alveolar nerve canal compressed; intimate relationship with facial artery and vein
- Donor site CTA: Right fibular vessels adequate; no anatomical variants
Virtual Surgical Planning
- Software: Mimics (Materialise) — 3D tumour and mandible reconstruction from DICOM data
- Osteotomy design: Virtual resection with 1 cm safety margins; fibula segment length calculated to match defect
- Patient-specific titanium plate: Pre-bent on 3D-printed mandible model before surgery — no intraoperative bending required
- 3D-printed cutting guides: Osteotomy guides with drill holes defining exact resection planes — sub-millimetre accuracy
Pathology
- Core needle biopsy: Solid/multicystic ameloblastoma — recurrence rate after curettage exceeds 50%; segmental resection with clear margins is the only curative treatment
Clinical Decision Making
Three compounding challenges defined the surgical strategy: a 10 cm mandibular defect requiring restoration of bone continuity, vertical height, facial symmetry, and dental function; a 28-year-old patient for whom an asymmetric or functionally compromised outcome was professionally and personally unacceptable; and the biological imperative of immediate reconstruction — delayed reconstruction allows soft tissue contracture that worsens the aesthetic result.
Dr. Zhang Zhiyuan's integrated strategy: Ameloblastoma is not cancer, but it behaves like cancer locally. Curettage is not treatment — it is a guarantee of recurrence. The only cure is segmental resection with clear margins. But for a 28-year-old woman, removing 10 centimetres of her jaw is not the end of the operation. It is the beginning. The reconstruction must restore the mandibular arc, the vertical height for dental implants, the soft tissue lining of the mouth, and the facial profile — all in the same operative session. Digital planning is what makes this possible. Without it, we are guessing. With it, we are executing a plan designed, tested, and refined before the patient enters the operating theatre.
Operative Procedure
Phase 1 — Digital-Guided Tumour Resection
Anaesthesia: General anaesthesia with nasotracheal intubation — nasal route maintains unobstructed intraoral access.
3D-printed guide placement: Osteotomy cutting guides positioned over mandibular dentition with sub-millimetre accuracy; drill holes define exact resection planes.
Piezosurgery osteotomy: Ultrasonic bone scalpel used for all cuts — selectively cuts mineralised tissue while sparing adjacent nerves and vessels. Critical at the distal osteotomy where the facial nerve marginal mandibular branch is at risk.
Tumour removal: En bloc resection. Intraoperative frozen section confirmed clear margins at both osteotomy sites — R0 resection achieved.
Dr. Zhang's operative note: The 3D-printed guide eliminates the most dangerous moment in jaw tumour surgery — when the surgeon decides where to cut based on intraoperative judgement alone. That judgement introduces variability. The guide removes the variability. The cut is exactly where we planned it, to the millimetre. The oncological margin is guaranteed before the blade touches the bone.
Phase 2 — Simultaneous Fibula Harvest
Parallel harvest: Second surgical team simultaneously harvested the right fibula — eliminating sequential waiting and reducing total operative time.
Fibula length: 12 cm harvested; 2 cm excess for precise trimming at reconstruction.
Double-barrel technique: Fibula longitudinally split and vertically stacked — doubling available bone height. A single fibula (12–14 mm diameter) is insufficient to support dental implants at correct occlusal height; double-barrel restores physiological mandibular height for implant-supported rehabilitation.
Vascular pedicle: Peroneal artery and venae comitantes preserved; skin paddle perforators identified for intraoral lining.
Dr. Zhang's technical note: The single most common reason for poor aesthetic outcomes after fibula jaw reconstruction is inadequate vertical height. A flat, thin jaw cannot support teeth at the correct height and the lower face looks collapsed. The double-barrel technique solves this. For a young patient who will wear implant-supported teeth for the next fifty years, the additional operative complexity is not optional. It is the standard.
Phase 3 — Fixation, Microsurgical Anastomosis, and Implant Placement
Fibula inset: Double-barrel fibula secured with pre-bent patient-specific titanium plate — no intraoperative bending required; precise facial contour restoration guaranteed.
Microsurgical anastomosis: Peroneal artery to facial artery (end-to-side); peroneal vena comitans to anterior facial vein (end-to-end). Doppler ultrasound confirmed pulsatile flow immediately after clamp release. Ischaemia time 45 minutes.
Immediate implant placement: Two dental implants placed in anterior and posterior double-barrel fibula segments under digital guidance — exploiting active bone remodelling in the early post-operative period to accelerate osseointegration.
Intraoral lining: Fibula skin paddle reconstructed intraoral mucosal defect — no separate skin graft donor site required.
Post-operative Course and Outcomes
- Flap monitoring: Continuous Doppler monitoring for 24 hours; no vascular crisis; flap fully viable
- Complication: Transient common peroneal nerve palsy (foot dorsum numbness) — full recovery at 3 months with neurotrophic medication
- No infection, no flap necrosis, no wound dehiscence
- Week 1: Liquid diet without nasogastric tube; swallowing intact
- 3 months: CT confirmed bony union at osteotomy sites; implant osseointegration confirmed
- 6 months: Gingival forming surgery; provisional prosthesis fitted; normal masticatory function; facial symmetry excellent; partial mental nerve sensation recovery
- 2 years: No tumour recurrence; final ceramic restoration completed; facial profile symmetric; returned to full-time design work
Expert Commentary — Dr. Zhang Zhiyuan
1. Ameloblastoma: Why Curettage Fails and Resection Cures
Ameloblastoma infiltrates cancellous bone through microscopic extensions beyond the radiographic margin — curettage invariably leaves residual tumour cells. Recurrence rates after curettage exceed 50% at five years. Segmental resection with 1 cm clear margins in all dimensions is the only reliable cure. This patient had already experienced one recurrence after curettage. The correct treatment at first presentation would have been segmental resection. The lesson is not that curettage sometimes fails — it is that curettage is the wrong operation for solid/multicystic ameloblastoma, regardless of tumour size.
2. Digital Surgery: Precision as an Oncological and Aesthetic Imperative
Virtual surgical planning and 3D-printed cutting guides have transformed jaw tumour surgery from an experience-dependent craft into a reproducible, precision-engineered procedure. The cutting guide guarantees the planned oncological margin at every osteotomy. The pre-bent patient-specific plate restores the mandibular arc with geometric precision impossible to achieve by intraoperative bending. In a 28-year-old patient whose professional identity is visual, the difference between a symmetric and asymmetric facial outcome is not a cosmetic detail — it is the difference between a life restored and a life permanently altered.
3. The Double-Barrel Fibula: Restoring Height, Enabling Teeth
The free fibula osteocutaneous flap is the gold standard for mandibular reconstruction — reliable vascularised bone, skin paddle for intraoral lining, and geometry that can be shaped to match the mandibular arc. Its primary limitation is vertical height. The double-barrel technique — longitudinal splitting and vertical stacking — doubles available bone height and creates a reconstruction that supports implant-retained prostheses at physiological occlusal height. For a young patient requiring dental rehabilitation for decades, this is not a refinement. It is the foundation of functional restoration.
4. Immediate Implants in Vascularised Bone: Compressing the Rehabilitation Timeline
The traditional sequence — reconstruction, then 6–12 months healing, then implants, then prosthetics — subjects young patients to prolonged functional and aesthetic compromise. Immediate implant placement in vascularised fibula exploits active osteoblastic remodelling to accelerate osseointegration. This patient had provisional prosthetic function at six months and final ceramic restoration at eighteen months. The conventional sequence would have required thirty to thirty-six months to reach the same endpoint.
How CMCS Shanghai Coordinated This Case
CMCS Shanghai supported Ms. Dubois from initial inquiry through two-year oncological and dental surveillance, including: pre-consultation review of external CBCT, CT, and pathology from the prior curettage; specialist referral to Dr. Zhang Zhiyuan at Shanghai Ninth Hospital's Oral and Maxillofacial Surgery Centre; bilingual interpretation throughout all consultations, virtual surgical planning sessions, and informed consent; coordination of contrast-enhanced CT with CTA, core needle biopsy, and pre-operative dental assessment; real-time surgical updates to the patient's family in France; post-operative ICU flap monitoring with daily bilingual updates; discharge planning in English and French; three-month and six-month CT surveillance with results translation; dental prosthetic rehabilitation coordination; and two-year oncological surveillance with direct liaison between Dr. Zhang's team and the patient's oral surgeon in Paris.
For international patients facing jaw tumours and complex facial reconstruction in Shanghai, Dr. Zhang Zhiyuan's team at Shanghai Ninth Hospital combines oncological precision, microsurgical excellence, and digital technology to restore not just anatomy, but identity. CMCS ensures that expertise is accessible — in the patient's language, with overseas physicians informed at every step, from biopsy through final dental restoration.
This case report is de-identified and published for educational purposes. All clinical details have been anonymized in accordance with patient privacy standards. CMCS Shanghai is a medical concierge service and does not provide direct medical care.
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