The bleach will eventually dissolve plaque but it does take time, it's not instantaneous. Plaque is essentially a rock. It's probably tartar or just stain from tea or coffee or smoking, if you are a smoker.
Yes, it is likely the visit for a cleaning by a dental hygienist at the dentist will take care of it. Sometimes it takes a deep cleaning to get the most ingrained stains. A power toothbrush, one of the rotary types will be better than anything you can do with your hand powered toothbrush. . . but don't over do either type. Consistent daily cleaning is better than too much. Don't use any type of abrasive cleaner.
Use Sensodyne if you have sensitive teeth, i.e. feeling pain in your gums or teeth. That's what it is for. Otherwise it is unnecessary expense over regular toothpaste of any other good brand. If you like it, it's OK to use for that reason. In our experience a couple of weeks of our protocol takes care of any tooth sensitivity by healing sores and strengthening damaged gums and weakened teeth.
Let me know about your visit and the results on the stains.
I just got out of my cleaning. They said my gums are very healthy! I only had one small cavity. They said there was hardly any plaque in my teeth and they were impressed. I haven’t been to have a cleaning in years but it seems like i never got compliments like this. I think the bleach and baking soda (and flossing) is doing its job. I think the cavity may have occurred before I got serious about my dental health. Is it possible that the bleach solution can actually heal a cavity that has formed, or can the bleach prevent me from getting new cavities in the future? I don’t plan on having any cavities ever again! (: