"Man vs. Machine: 3D Milling of Auricular Frameworks".

Area of Science:

• Biomaterials engineering
• Medical device manufacturing
• Plastic and reconstructive surgery

Background:

• Autologous rib harvest and manual carving are standard for microtia reconstruction.
• Cadaveric costal cartilage grafts show clinical promise for auricular reconstruction.
• Point-of-care framework production is a potential advancement.

Purpose of the Study:

• To assess the feasibility of 3D milling cadaveric costal cartilage for auricular framework production.
• To evaluate the efficiency of 3D milling compared to traditional methods.

Main Methods:

• A Nagata/Firmin style framework was modeled in soap and 3D scanned.
• A 3-axis CNC machine was used to mill an en bloc framework from cadaveric costal cartilage.
• Milling time, dimensional accuracy, and volumetric similarity were analyzed.

Main Results:

• Total milling time was approximately 7 minutes, with 20 minutes for finishing, totaling 27 minutes.
• This is a significant reduction from the 1-2 hours required for manual carving.
• Dimensional comparisons were within 2 mm, and volumetric analysis showed 71% similarity to the model.

Conclusions:

• En bloc 3D milling of cadaveric costal cartilage is feasible and efficient.
• This method substantially decreases framework production time and allows accurate reconstruction.
• Potential benefits include cost savings, improved patient safety, and patient-specific reconstruction; sterility is the next focus.