Dental crown sensitivity even after a year. Is this normal?

There are a couple of things to have looked at by your dentist.1. Is the crown sealed one hundred percent.2. is there nerve damage that could lead to a root canal 3. Is there a crack that may lead to an extraction and dental implant. 4. Bite might be slightly high and need adjusting.Good luck. 

There are several factors that can cause for your crown to have sensitivity after such a long time among these factors the most common are:

Your crown might not be selling correctly, this cause sensitivity specially with could beverages or even opening your mouth in cold wheatear.

Nerve damage while prepping for the crown, the nerve is an unrepairable flesh therefor this condition ends on a root canal.

A micro fracture, although this normally does not cause sensitivity but discomfort of pain by chewing it is still a possibility and is better to discharge them all before taking a final decision.

If your hygiene and eating habits are proper the crown should not affect the tooth next to it unless there is a part in the interproximal area not sealing and this can cause bacteria to accumulate easier causing periodontal pockets and decay.