JaW PrinT is a prospective observational cohort study evaluating the effectiveness of two different techniques of mandibular reconstruction.

JaW PrinT is a 'real-world' prospective observational pilot study, evaluating the clinical effectiveness, usability and economics of two approaches to mandibular reconstruction surgery (using flexed titanium versus printed titanium patient-specific osseosynthesis plates). Patient participants will be recruited prospectively over a minimum period of 18 months (with observation of at least 10 participants in each treatment pathway). The figures are based upon the historical clinical practice of the research site, with both techniques in equal use; choice depending on resources, surgical training requirements and surgeon's clinical preference.

As a purely observational study, treatment choice will be made in the normal clinical manner and will in no way be influenced by the study itself.

Participants will be followed up at their routine outpatient clinics (6 weeks, 6 months and 1 year postoperatively) with prospective outcomes data collection.

Participants will be recruited prospectively as they present as new patient cases to the Maxillofacial and Head & Neck cancer multidisciplinary team (MDT) clinics. Once a potential patient participant has been given his/her diagnosis and it is confirmed by the principal investigator (PI) that he/she meets the inclusion criteria, clinic staff will provide the potential participant with an invitation letter introducing the study as well as a patient information sheet and consent form (explaining the available options of participating or refraining from the study). Patients will be allowed up to 24 hours to decide whether or not to participate as to avoid any impact/delay on the scheduling of their clinical treatment. The PI will obtain written informed consent from willing participants.

Upon recruitment, provision of informed consent and collection of baseline data, as per standard clinical practice, the patient participant's CT scan data is used to produce a virtual surgical plan for the mandibular resection and fibular free-flap reconstruction. Once the clinically optimal reconstructive surgical plan is established by the surgeon and technician, the choice of surgical approach will be made in the routine clinical manner by the surgeon: Pathway A (pre-flexed customized mandibular reconstruction plate and cutting guides) or to pathway B (SLM customized mandibular reconstruction plate and cutting guides). Both treatment pathways are already part of routine/standard clinical practice at the research site.

The expected/planned patient numbers for this study are based upon the historical workload of the department, typically at 10-20 cases annually. A recruitment period of 18 months with follow-up for 1 year fits within the time constraints of the postgraduate student investigator's PhD timeline.

Inclusion Criteria:

• Age over 18 years
• Able to provide informed consent
• A planned fibular free-flap reconstruction of the mandible
• Planned post operative surveillance CT scan 6 months following surgery

Exclusion Criteria:

• Clinically unfit or inappropriate (based upon prognosis/life expectancy) for reconstruction using free tissue transfer techniques
• Patients with planned surgical defects involving formal reconstruction of the condyle. (Clinical use of printed plates for condylar reconstructions would in effect be 'off-licence' and non-standard treatment which is beyond the remit of an observational research study).
• Flap failure within the study follow-up period, as this would require early removal of the flap and therefore preclude collection of follow-up outcome data. However, any flap failures (and associated clinical complications/events) will be recorded and reported.

Patients from the study site region requiring free-flap reconstruction of the mandible (e.g. for tumour or osteoradionecrosis):