Security in jewelry is largely a question of intent. A well-made hinged closure distinguishes between the accidental force of everyday movement and the deliberate pressure needed to release it, and responds accordingly.
Elemental Detail
The recommendation for platinum and 18kt gold posts for sensitive ears is a chemistry argument. Their high precious metal content means lower alloy exposure at the piercing, and it's the alloy elements, particularly nickel, that cause sensitivity reactions in most people.
Industry Insight
A lab-grown diamond is pure crystalline carbon. All the same atomic arrangement, the same crystal lattice, the same hardness and optical behavior as a mined diamond. The controlled laboratory environment replicates the geological formation, and the result is structurally indistinguishable.