Introduction: We present a comparative study of advantages and disadvantages of using a custom system designed osteosynthesis with CAD–CAM technology in large maxillomandibular advances.

Methods: We present 8 cases of skeletal correction of severe OSA. In four of them conventional miniplates were used, in the other four, a custom osteosynthesis system designed with CAD–CAM technology. After digital 3D surgical planning, we have obtained the STL files that have allowed the design of an osteosynthesis system adapted to the patient’s skeletal surface. The use of cutting guides allowed planning reproducibility.

Results: In the 8 cases planned objectives were achieved. Personalized plates allowed a good fit of the facial buttresses, without altering the characteristics of the titanium and offering maximum stability although they failed to reduce operative time. The biggest drawbacks were planning times, manufacturing and cost, as well as the limitations of the 3D planning programmes. A comprehensive study and an accurate reproduction of the expected movements by the surgeon are required, specially in oclusal plane change.

Conclusions: Customized systems can offer a very high level of accuracy. These systems can be advantageous in large maxillomandibular advancements and in cases where there are anatomical defects difficult to treat with conventional systems.