Lower incisor broken. No pain, the fracture at the gum line inside of the tongue. Modest bone loss , not severe.

From what you have explained, I would not invest money in restoring this
root, and that is all that is left of the tooth. Placing crowns on the adjacent weakened tooth
may not be cost effective in the long run.
An implant or implants may be a better option. Here’s my reasoning. The teeth are weak because they are so small
and I am assuming there has been bone loss as well. Yes, you could place a post and build up the
tooth but longevity is the question. Talk
to your dentist about placing implants in the place of this tooth, and looking
forward, on the other teeth as well. The
best bone in the mouth for implants is located in the lower front of the mouth. Implants here will last a lifetime if they
are properly cared for!

It is difficult to give you an answer without a picture of your mouth. I will tell you that the tooth was not weakened by normal dental hygiene visits and removal of plaque from your teeth. Your dental hygienist is a very trained individual and takes continuing education to keep up her skills. I suggest visiting with your dentist to determine what course of treatment is the best for your situation.

It sounds like you have periodontal disease with bruxism. This mean your teeth grinding abnormalities are causing the thinning at the neck of the tooth. Cleaning isn't removing any significant tooth structure. To strengthen your teeth is recommend a night guard, possibly a day guard and seeing a periodontist.