I have an older Pixma printer that does not have 'Air Print' compatibility, so have been using a program on the computer (not needed on the iPad) called FingerPrint which basically mimics the Apple wireless print feature.
The other day my iPad would not print to either my Canon nor my Brother laser printer (this has happened in the past) - here are the steps that I usually perform: 1) Restart/Reset the iPad; 2) Turn the printers off, wait a short time, and then restore power; 3) Power recycle the modem & the router; and 4) Reboot the computer.
Now I usually do these in sequence and check to see if the printing function returns at each step - a few weeks ago I had to go to step 4 above, but sometimes just steps 1 and/or 2 have worked. Let us know your results and good luck!