Probably a dead button, if you have touch but not home button then you can either turn on the on screen home button and still use the touch sensor, or swap the home button and get home but not touch, or take it to Apple and get them to swap it and get everything as it should be..

If you have damaged the small chip section that plugs into the cable that runs up the back of the screen then, you are most probably screwed, you can get a new home button but will lose any "Touch" features of the phone as any new home button wont come with a touch sensor. At least Apple have updated the iOS so it doesnt brick the phones anymore but just disabled the "Touch" side...

IF Apple have coded the TouchID into the phone directly somehow then you either have TouchID using the original home button, or, you have Home Button use and no TouchID. I have swapped the metal backing as well as the screen, as far as I can see there is no damage to the Home Button/TouchID assembly or the ribbon cables. Phone has been updated as well and didn't brick. What we need is someone that can write something that'll recode a TouchID sensor to a phone if the assembly is swapped..

I replaced a screen on my 6+ and the Home button stopped working, I also replaced the shield/ribbon as well but still no Home button, TouchID works fine though....