Abstract
Aims and ObjectivesThree-dimensionally printed cranio-maxillofacial (3DPCMF) implants have evolved to become the standard of practice in leading centres internationally. This thesis aims to outline the future role of these devices by evaluating the current evidence base and factors that might affect their routine use. Specific focus is placed on mandibular reconstruction as a key application, aiming to improve upon the quality of available clinical evidence and explore how printed titanium can lead to the development of novel, more effective and safer surgical techniques.
Methods
A mixed-methods approach is adopted, including a critical review of the literature in general, and systematic review of the evidence base for printed titanium in mandibular reconstruction. A national cross-sectional study evaluates end-user opinions surrounding
clinical applications and logistics for using 3DPCMF implants in general. To further evaluate clinical outcomes of printed titanium in free-tissue mandibular reconstruction, a two-centre prospective cohort study, which alongside the validation of a purpose-made tool to score bony healing of flap osteotomies, provides pilot data and research methodology for a larger-scale clinical study. Exploring the potential for printed titanium cranio-maxillofacial implants to shape and evolve future surgical techniques.
Results
Three-dimensionally printed cranio-maxillofacial implants have evolved not only because of new additive manufacturing techniques, but also from advances in (reverse) virtual surgical planning that are required for complex digital implant design. Numerous potential routine clinical applications are identified, with key indications including free-tissue mandibular reconstruction, complex deformity surgery and orbital floor reconstruction.
For mandibular reconstruction, the literature reports numerous benefits relating to reconstructive accuracy and quality of life outcomes but few limitations. Prospective clinical pilot study data supports the notion that printed titanium can improve
morphological/reconstructive accuracy compared to pre-bent reconstruction plates (regardless of using patient-specific surgical guides). Methods to test this (as well as bony union and quality of life outcomes) in a larger-scale clinical study have also been refined.
Within current medical device regulations, the development of a novel mini-plating device is clinically feasible, with advantages over existing techniques and unique commercial potential.
Conclusions
Considering clinical effectiveness and logistical/technical feasibility, 3DPCMF implants have become a routine treatment approach for key clinical indications, especially as surgeons increasingly adopt reverse/virtual surgical planning. However, the industry needs to work harder to better-inform surgeons of actual costs and turnaround times which are variably understood.
For mandibular reconstruction, the literature reports few limitations but appears biased. The study methodology developed in this thesis will further clarify the apparent accuracy benefits of printed titanium over ‘next-best’ (semi-digital) alternatives as well as bony union and quality of life outcomes in a larger-scale study.
Three-dimensionally printed patient-specific cranio-maxillofacial implants can both respond and lead to evolution in surgical technique with improved clinical effectiveness for surgeons and patients, as well as economic gains for the manufacturing industry. Providing larger prospective clinical studies continue to demonstrate incremental functional and quality-of-life gains for patients, as well as technical gains for surgeons, the role of 3D-printed cranio-maxillofacial implants is not only protected for key surgical procedures, but rather likely to expand into more routine applications.
| Date of Award | 2023 |
|---|---|
| Original language | English |
| Supervisor | Mark Williams (Supervisor) & Joyce Kenkre (Supervisor) |