Three-dimensional occlusal and interproximal contact detection and display using virtual tooth models

A machine for assisting a user in planning treatment for an orthodontic patient, comprising:

• a central processing unit;
• a user interface;
• and
• memory storing a set of instructions for said central processing unit and a data set representing a set of virtual teeth of a patient including the teeth of an upper arch and a lower arch;
• said instructions comprising treatment planning software enabling a user to move the virtual teeth to a proposed set-up;
• wherein said instructions further comprise a set of instruction for determining at least one occlusal contact of said upper and lower arches of said virtual teeth in said proposed set-up when said virtual teeth are in an occluded condition;
• wherein said set of instructions calculates a sphere around points on a surface of virtual teeth in one of said arches, and enlarges the size of said sphere until intersection of said sphere with a surface of a tooth on the opposing arch occurs thereby finding the separation distances between said virtual teeth in said opposing arches thereby enabling determining said at least one occlusal contact;
• and
• wherein said set of instructions includes instructions for display of said virtual teeth on said user interface with said occluded contact displayed in a manner readily observable to said user.

A method for determining the proximity of teeth of upper and lower jaws of an orthodontic patient, comprising the steps of:

• a) storing data representing a three-dimensional model of teeth from the upper and lower arches of the patient in a memory associated with a computer;
• b) simulating motion of said upper and lower arches relative to each other;
• and
• c) calculating, with said computer and model, distances between surfaces of teeth in one of said upper and lower arches and surfaces of teeth in the other of said upper and lower arches during said simulation of motion;
• wherein said step of calculating includes the step of calculating a sphere around a plurality of points on a surface of a tooth in said one arch of said model, and enlarging the size of the sphere until the sphere intersects with a surface of a tooth on the opposing arch in said model.