Rapid prototyped patient specific guiding implants in critical mandibular reconstruction

- The progress of medical modelling and computer aided design is rapid. Different patients' specific implants (PSI) have become available.
- We have carried out a prospective follow up study on mandibular reconstruction using a new design of a PSI, with a scaffold part attached to a solid large plate. The total number of patients is 14 including a total of 15 cases.
- The purpose of the study was to evaluate the results and the use of PSI's combined with microvascular flaps in 12 of 15 cases with benign or malignant tumours demanding continuity resection of the mandible. The scaffold PSI was filled with β-tricalcium phosphate granules and autologous bone with an average follow up of 33 months clinically and of 21 months radiologically.
- Our designed PSI showed a very good fitting and in nine cases the healing was uneventful. A major complication, however, was the lingual border of the PSI being too high leading to perforation of the mucosa with infection resulting in total or partial removal of the PSI in four cases.
- The benefits are decreased rate of donor site complications and more accurate and prompt surgical procedure.

Large tumours of the mandible need immediate reconstruction to provide continuity of the mandible, satisfactory function of the jaw, as well as an acceptable aesthetic outcome. In this prospective study we described the immediate reconstruction of the mandible using computer aided design and 15 rapid prototyped patient specific implants (PSI) in 14 patients suffering from benign or malignant tumours demanding continuity resection of the mandible. The scaffold PSI was filled with β-tricalcium phosphate granules and autologous bone. Microvascular reconstruction was additionally needed in 12/15 cases. The clinical follow up was on average 33 months and the radiological follow up was on average 21 months.In nine cases the healing was uneventful. One patient lost the microvascular flap during the first postoperative week and one patient needed a revision due to perforation of the mucosa at the site of the PSI. Four patients had a major complication due to perforation of the mucosa leading to infection, which resulted in the total or partial removal of the PSI. The PSI seems to be a promising solution for treatment of patients demanding large reconstruction after mandible resection. The benefits are decreased rate of donor site complications and more accurate and prompt surgical procedure.