Repairing seriously damaged bones is normally a delicate art; while you want to regrow bones quickly, you also have to carefully manage that growth to produce the right shape. Thankfully, Rice University has created a gel that makes it easier to produce only the bone tissue a patient needs. The material kickstarts bone regeneration using a patient’s stem cells, but it also dictates where that growth occurs by forming a scaffold that degrades only when tissue takes its place. Effectively, doctors just have to fill an area with the gel and wait for nature to do the rest. The technique should initially be useful for repairing skull damage, but it’s likely to be handy for both less vital operations and cosmetic surgery — don’t be surprised if doctors can eventually give you a facelift by reshaping your cheekbones.