In the last week and a half I've had discomfort in my upper gums that I cannot account for and I'm hoping you can offer some advice.
Prior to using your system, I had lots of sensitivity at the gumline when I would eat or drink anything hot or cold or acidic but that disappeared shortly after using your system twice a day.
A week and a half ago I had discomfort in my gums (for the first time in years) as soon as I started eating frozen yogurt. Not only did the cold penetrate right into the gumline (like it had before I started your system), but it also hurt - it felt like lots of needles poking me - on the higher portions all over my upper gums (which I've never experienced). Since then I have had that same needle poking feeling often, particularly when I drink tea (herbal). Just to make sure I was using the right products, I checked my ACT and Listerine bottles today and they are the correct ones (ACT is alcohol free and ADA approved, and I have the regular Listerine which is ADA approved) so now I'm stumped.
My immediate thought is that there is a change in your general health, although there is a laundry list of reasons that your teeth may be experiencing more damage.
A small change in diet can increase mouth acidity and mouth dryness (of any kind) will damage teeth - especially if it occurs at night.
Whatever caused the changes - you have the tools to stop the damage and reverse it!
This can be because of stress, or hormonal changes, talking more, different diet with more acidity ( food or drinks) or just some kind of worry.
If you have any new medication, allergies or even a cold it can cause you to breathe through your mouth and this will dry your mouth.
A course of antibiotics, exposure to foods like spinach or rhubarb ( they contain oxalic acid) or even eating a lot of citrus can damage the healthy film that normally covers and protects your teeth.
Increase your Xylitol:
To combat the increase in "risk/damaging factors" you need to pump up the "good/healing treatments"
You may want to add granular xylitol to your day - maybe a teaspoon in a water bottle to sip during the day.
Keep eating your Zellies after meals etc - but protect your teeth more - with the xylitol-water during the in-between hours.
Zellies chewing gum can be a particularly good "healer" and sometimes seems better than mints for healing sensitivity - although I am not a big gum chewer - and I don't think you are either.
Keep Flossing to a Minimum
I am not sure if you floss - but if you do, be very gentle, keep it to a minimum and perhaps give yourself a flossing holiday to see if this makes things better.
I am assuming that you are using Closys before you brush - Crest Cavity Protection toothpaste and the other rinses in the system ( with no water rinsing in between).
If the above suggestions do not help then add one extra rinse with ACT rinse during the day - after lunch.
The sensitivity is a warning sign - and your teeth are calling for more help.
Xylitol and my system are the "help" your teeth need.
Just give them a little more help than you usually do - and they will heal up again nicely!
Fish oil supplements, vitamin C supplements ( but protect your teeth from any and all citrus acidity with a Zellies mint) and get out in some sunshine for some vitamin D.
You may also want to consider probiotics - ask in your local health food store.