34th Annual Scientific Meeting proceedings

Computer-Aided Design (CAD) allows complex and patient-specific three-dimensional geometries to be designed that are configured to the needs of an individual patient.  Additive Manufacturing (AM) – otherwise known as 3-D printing – allows realization of the computer-designed implant. CAD and AM provides a freedom from the design constraints of conventional manufacturing processes, whilst keeping build time and costs to a realistic level.

Previous research into maxillofacial defects has tended to use either locking plates, compression resistant matrix (CRM) infused with rhBMP-2, or autogenous bone. These techniques are largely limited to focal defects, and none provide for replacement of articulation of the mandible. In humans, reconstruction of the mandible is typically achieved by microvascular transfer of autogenous bone segments. These techniques are complicated and can have a high morbidity.

Titanium and its alloys are rapidly becoming materials of choice for biomedical implants due to many favourable properties. The advent of computer aided design and 3D printing technologies using titanium powder allows creation of an implant that is uniquely designed to fit a specific patient.  A crucial design element of the titanium implant is a porous scaffold that enables vascular and cellular ingrowth into the implant, such that new bone tissue will ultimately form on the implant surface. This potential for complete integration of the implant into the host tissues is a ‘holy grail’ for human biomedical implants; integration minimises the potential for infection and implant failure, which can be devastating for the patient.

Custom designed implants for maxillofacial reconstruction are rapidly gaining acceptance in human surgery, and have been utilised in a variety of situations, particularly for craniofacial reconstruction and joint reconstruction. Due to the precise geometric fit of the custom implant, surgical complexity and operating times are reduced, with improved cosmetic outcomes.

Veterinary experiences with 3D-printing and custom designed implants for maxillofacial conditions including extensive neoplasia and trauma will be described in this lecture. Current experience suggests these implants can be well tolerated by patients, with a low rate of complications. Crucially, rapid restoration of normal mandibular dynamics may allow wider excision of affected tissues to be considered. This may serve to improve oncologic outcomes, whilst preserving acceptable function to allow a return to independence of eating and grooming behaviour.

References

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