System and method for automated generating of a cutting curve on a surface

A computer-implemented method for automated generating of a cutting curve on a gingival surface to facilitate cutting of an aligner material, said computer-implemented method comprising:

• generating an initial gingival curve within an interproximal area between two teeth;
• replacing said initial gingival curve with a modified portion to generate a dynamic cutting curve;
• outputting said dynamic cutting curve for conversion into machine executable code for cutting of the aligner material;
• and
• automatically adjusting a cutting tool away from an initial cutting tool line and away from an inner shell along a cutting tool axis to avoid collision of the cutting tool with teeth, an attachment device, an inner shell or a fixture when cutting the aligner material.

A computerized system for automatic generation of a cutting curve on a gingival surface to facilitate cutting of an aligner material, said computerized system comprising:

• a microprocessor;
• and
• a data storage device including a plurality of algorithms;
• the microprocessor configured by the algorithms to:
• generate a plurality of gingival parametric curves within an interproximal area between two teeth representing a gingival surface;
• convert a digital data format that defines initial gingival curves along teeth on jaw structure of a patient into a plurality of points disposed on each side of the interproximal area;
• project a sample of the plurality of points on to a plane in three-dimensional space which passes through an average of the sample of the plurality of points to generate a second pair of curved portions;
• generate a third pair of curve portions having a predetermined offset from the second pair of curved portions including an intersection point and a minimum radius in the interproximal area;
• determine tangent points between a cylinder having an axis at the intersection point and a radius equal to the predetermined offset and the sample of plurality of points and cylinder intersection points between the cylinder and a portion of the gingival parametric curves;
• and
• generate a digital data format that defines a dynamic cutting curve within the interproximal area that is made to fit through at least a portion of the sample of plurality of points, the cylinder intersection points and the tangent points.

A computer-implemented method for automated generating of a cutting curve on a gingival surface to facilitate cutting of an aligner material, said computer-implemented method comprising:

• generating a digital data format that defines initial gingival curves along teeth on a jaw structure of a patient and a plurality of gingival parametric curves within an interproximal area between two teeth and converting the digital data format that defines the initial gingival curves into a plurality of points with geometric information associated with a first pair of gingival curve portions of the initial gingival curves residing on each side of the interproximal area;
• generating an average plane in three-dimensional space which passes through an average of a sample of the plurality of points, projecting the sample of the plurality of points on to the average plane to generate a second pair of curved portions, generating a third pair of curve portions having a predetermined offset from the second pair of curved portions including an intersection point and a minimum radius in the interproximal area, generating a digital data format that defines cylinder having an axis at the intersection point and a radius equal to the predetermined offset, determining tangent points between the cylinder and the sample of plurality of points and cylinder intersection points between the cylinder and a portion of the gingival parametric curves;
• and
• generating a digital data format that defines a dynamic cutting curve within the interproximal area that is made to fit through at least a portion of the sample of plurality of points, the cylinder intersection points and the tangent points;
• and
• converting in a microprocessor the digital data format that defines the dynamic cutting curve into machine executable code for cutting of the aligner material.