Much thanks for all of the replies.

Unfortunately, the fillings are composite heliomolar and not amalgam so it makes it unlikely that it would cause lichen planus (but not impossible of course and not ruling it out).

Still waiting on results unfortunately. Surgeon said they should have the results within 10 days but unfortunately the next available appointment with ENT was not until the 10th of March. I saw my GP yesterday and tried to get him to chase things up to get results earlier but hospital did not seem to have any record of the biopsy... (It should have been recorded that they had the sample at least!)

I'm going to keep chasing things up to see if I can get the results earlier rather than wait another 2 weeks.

D