Nope, Canon's later models still do not use permanent heads. They're semi-permanent if you please - you don't HAVE to throw them out with every round of ink, but still, they're replaced (or taken out to clean or soak) at the flick of a lever, and they're way less expensive than Epson's piezo heads. The entire current product line is like this.
And besides, even the disposable head-ink monoblocks do dry out before they get empty - especially with people who don't print much, and especially with HP's DeskJet 500 through 999 printers because the sealing lid in the head's parking position wears and warps very quickly, losing its airtightness. The soaking trick works with those too, of course ... particularly with HP's that have the lowest resolution and thus largest nozzles of them all.
regards, Peter