Among different approaches for 3D face recognition, solutions based on local facial characteristics are very promising, mainly because they can manage facial expression variations by assigning different weights to different parts of the face. However, so far, a few works have investigated the individual relevance that local features play in 3D face recognition with very simple solutions applied in the practice. In this article, a local approach to 3D face recognition is combined with a feature selection model to study the relative relevance of different regions of the face for the purpose of discriminating between different subjects. The proposed solution is experimented using facial scans of the Face Recognition Grand Challenge dataset. Results of the experimentation are two-fold: they quantitatively demonstrate the assumption that different regions of the face have different relevance for face discrimination and also show that the relevance of facial regions changes for different ethnic groups.