diff --git a/skfem/mesh/mesh3d/mesh3d.py b/skfem/mesh/mesh3d/mesh3d.py
index 11c72c645..218714c5f 100644
--- a/skfem/mesh/mesh3d/mesh3d.py
+++ b/skfem/mesh/mesh3d/mesh3d.py
@@ -27,10 +27,7 @@ def edges_satisfying(self, test: Callable[[ndarray], bool]) -> ndarray:
             the output set.
 
         """
-        mx = 0.5 * (self.p[0, self.edges[0, :]] + self.p[0, self.edges[1, :]])
-        my = 0.5 * (self.p[1, self.edges[0, :]] + self.p[1, self.edges[1, :]])
-        mz = 0.5 * (self.p[2, self.edges[0, :]] + self.p[2, self.edges[1, :]])
-        return np.nonzero(test(mx, my, mz))[0]
+        return np.nonzero(test(self.p[:, self.edges].mean(1)))[0]
 
     def boundary_edges(self) -> ndarray:
         """Return an array of boundary edge indices."""