Silicon fillers are notorious for causing late reactions including nodules and granulomas. Any type of device which can disrupt the silicon such as lasers, Infini, or other injections have the possibility of reactivating the silicon and causing one of these late reactions. It doesn't even need to be in the same area as the prior silicon. I'd be very cautious with proceding with the Infini in a patient with silicon. Other fillers are safe with Infini if they are deeper than the dermis. If they are in the dermis, HA fillers are at risk to be degraded. Bellafill is safe at any depth because it's melting point is at 160C, much higher than the 70C that the Infini heats up to.