Hi Kinola67,
I'm on Dosulepin, a 'sister' med to amitryptiline. Both of these meds are tricyclic antidepressants and one of their more common side effects is dry mouth. I've always had it for the 20 years I've been on mine! (lifelong GAD & Depression is SUCH fun!)
I've noticed mine has gotten worse since I became peri 4 years ago but that the level it takes varies. Dry mouth can make gums recede (mine certainly have) and oestrogen issues can certainly make teeth sensitive, which is my problem.
All I can suggest is you get a good 'gum' toothpaste, I use Oral B or Sensodyne, ditch the standard medium hard head toothbrush and switch to a sensitive soft head & brush lightly. And don't forget to drink lots of water! I tend to have water by me 24/7 and take regular mouthfuls on the bad days. The gum is a good idea (though my mouth is crowded as I still have all 4 wisdom teeth so I have a tendency to bite the sides of my mouth to shreds if I chew gum so I go for sweets ).
It may ease off as you get used to the HRT. I've been on my HRT dose for just over 3 months and unless i'm having an anxiety bout (godsdamn unpredictable oestrogen spikes and dips!) my dry mouth has improved drastically.
As for the loss of smell that might be down to lack of water too, I use a saline nasal spray if mine gets too dry.
Hope thats of some help.