40% titanium is a joke from a television show, however yes there is a bit of special treatment for titanium if you are going to do bars this way.
as you know Titanium presents and Oxidization layer even 5 minutes after sandblasting, so be very careful and only blast one tooth at a time, and quickly add opaque. for big units like you have there, it takes a long time to do one tooth at a time, but if you are careful, it will work. opaque layer must be added before oxidization or else the opaque will not adhere, it will cure and simply fall off.
by adding the opaque straight away, you can begin scanning the surface and you won't need to add more scan spray because opaque is enough. so no more rubbing off the spray. the copings or crowns you design on this opaque layer will also require less adjustment to seat.
i don't like those big metal bars, its not easy to work with. i also fundamentally disagree with the philosophy of making this bar due to the amount of transferred force of mastication from tooth to implant; i think the bar should help absorb the impact instead of transferring force so i am conducting research into softer materials.