Send your attorney a letter and tell him if the matter is not taken care of immediately, you'll contact the state bar association or state supreme court, whichever one handles complaints about attorneys. Give him 10 days to respond.
You should be able to get the deductible back but you'd have to go after her probably in small claims. However, before doing so, if you were injured it can make a difference. Before going anything, consult a personal injury in your area to investigate it for you. Best to you
Not sure this rises to malpractice. You may very well have a claim against the dentist though unless it can be straightened out with the insurance company. You use it in the plural so you're probably talking about a lot of money. By all means see an attorney that does malpractice though so it can be looked into as well as an attorney that can sue for the loss and possibly the cost of replacing the implants.
They have the right but the court can overrule it. Not likely it would given their ages and the other information you have here. It's up to you to file. An attorney representing you would be preferable.