Dental Tool and Guidance Devices

A dental overlay for temporary installation into the mouth of a patent to limit the tooth structure removed from a tooth under treatment, said overlay comprising:

• (i) a base having one or more surfaces for contacting portions of one or more teeth in a patient to secure the overlay in a suitable position with respect to the tooth to be treated, and one or more open areas for exposing the tooth structure for removal;
• and
• (ii) a cutting guide comprising one or more sets of guide walls, wherein adjacent guide walls of each set and their surfaces have a predetermined configuration capable of contacting one or more guide projections of a dental instrument to limit the movement of the dental instrument and its tooth treatment assembly to restrict tooth structure removal to the predetermined three-dimensional portion of the tooth for treatment.

A method for treating a working tooth in a patient's mouth by removing portions of its structure, said method comprising the steps of:

• determining the three-dimensional structure of the working tooth to be removed for treatment;
• providing the dental instrument comprising a tooth cutting element for removal of a portion of a tooth's structure and one or more guide projections extending from the instrument in the direction of the tooth to be treated when said tooth treatment element is in operating position for tooth structure removal;
• preparing a dental overlay having a cutting guide with a configuration that is capable of contacting one or more guide projections of the dental instrument to limit the movement of the dental instrument to restrict the structure removed from the tooth under treatment to the predetermined three-dimensional portions of tooth structure for the treatment.

26-34. (canceled)