TOTAL MANDIBULAR DEFECT RECONSTRUCTION BY TOTAL TITANIUM PATIENT-SPECIFIC IMPLANT: CLINICAL EFFICACY AND LONG TERM FOLLOW UP. CLINICAL CASE.

The aim of this clinical case in demonstrating the possibility of replacing total defect of the mandible with a patient specific implant and the result of long-term follow up. Literature data on the replacement of total mandibular defects are extremely limited and they are presented by only several clinical cases where various surgical approaches were used. In the available literature, there are two approaches to solving this problem, including the replacement of the jaw with vascularised bone grafts, of which the fibula flap is the most promising, and the implantation of endoprostheses of the jaws, of which patient-specific anatomical endoprostheses made using additive technologies are the most advanced. The concept of using patient-specific endoprostheses of the whole mandible is considered revolutionary because it has a number of significant benefits, including the greatest accuracy in restoring the anatomical shape of the mandible. One of the unresolved problems associated with the installation of total mandibular endoprostheses is the prosthetic rehabilitation of patients using fixed structures. The analysis of the presented case can be a good tool for the clinician and bioengineer while making the final decision on the treatment method and modality in patients who need an identical option for the repair of a mandibular defect. Based on CT data, we can conclude that the employed approach, methodology of design and manufacture of patient-specific titanium mandibular endoprosthesis for the total defect demonstrated the sufficient efficacy, which suggest the need for further systematic studies to address this issue.

Automatic evaluation of the orbital shape after application of conventional and patient-specific implants: Correlation of initial trauma patterns and outcome.

PURPOSE: To evaluate the precision of orbital shape reconstructions using either conventional plates (CPs) or patient-specific implants (PSIs) to treat different types of orbital fractures, and to evaluate their clinical outcomes. METHODS: A total of 92 orbital-reconstruction patients were included. Forty-seven patients, treated with PSIs, formed the main group. The remainder, treated with CPs, were the control group. All patients were examined pre- and postoperatively using computerized tomography (CT) and evaluated for enophthalmos and diplopia. Evaluation of differences in orbital shape between damaged and intact orbits after surgery was performed by commercial orbital analysis software. RESULTS: In the main group, mean orbital shape difference between damaged and intact orbits after surgery was 0.137 ± 0.8 cm3 (range -1.7-2.3 cm3). In the control group, the mean shape difference was 1.05 ± 1.9 cm3 (range -1.8-8.3 cm3), significantly higher (p = 0.007). Diplopia occurred in seven PSI patients three months after surgery (14.9%) and in thirteen CP patients (28.9%) (p = 0.181). Enophthalmos occurred in five PSI patients (10.6%) and in sixteen CP patients (35.6%) (p = 0.001). CONCLUSION: Precise orbital reconstruction prevents the development of enophthalmos after trauma in patients with orbital wall fractures. In patients with preserved infraorbital buttresses and posterior orbital ledges, there were no significant clinical differences between PSIs and CPs. For cases requiring cantilevered reconstruction, including those with zigomatic or maxillary fragment repositioning, preference should be given to the PSI procedure for both effectiveness and predictability.