Method and apparatus for dental virtual model base
Method and/or apparatus embodiments can provide a virtual orthodontic base, adapted to each virtual 3D dental model of the teeth (e.g., upper and lower jaw). The virtual orthodontic base should match each 3D model (e.g., size), conform to prescribed dimensional requirements and still be rapidly calculated. The 3D virtual teeth model can be provided or reconstructed (e.g., from a laser scanning, intra oral camera scanning or x-ray scan of a plaster, a negative impression (e.g., alginate or silicon) of a patient's dentition or directly from the patient's mouth).
1. A computer-implemented method for generating a digital model base from a digital model of a patient's dentition, the method comprising:
forming an initial virtual base from a plurality of prescribed dimensions of a selected virtual base type;
obtaining a 3-D digital model of the patient's dentition;
determining bounding dimensions of the 3-D digital model of the patient's dentition;
performing a first translation of the initial virtual base based on the bounding dimensions;
performing a second translation of the translated virtual base based on local criteria to form the digital model base; and
displaying, storing or transmitting the digital model base.
2. The method of claim 1 , wherein the selected virtual base type is a regulated virtual base type or complies with the American Board of Orthodontics regulations.
3. The method of claim 1 , wherein the bounding dimensions include a 3-D bounding box of at least one of portions of an upper dental arch, portions of a lower dental arch, or both the upper dental arch and the lower dental arch in occlusion.
4. The method of claim 1 , wherein the digital model base comprises an upper virtual base and further comprises a lower virtual base, and wherein the plurality of prescribed dimensions of a selected virtual base type include (i) length of an oblique face of at least one pair of sides comprising a rear corner side, (ii) an angle of the rear corner side to a back side, (iii) an angle between one side of a second pair of sides comprising a front side and an orthogonal line from the back side; a range of height encompassing the distance from a top surface of the upper virtual base to a bottom surface of the lower virtual base, and a height limit of the upper virtual base and the lower virtual base.
5. The method of claim 1 , wherein the first translation of the initial virtual base comprises a global translation of the initial virtual base scaled from front to back depth dimension and a left to right width dimension.
6. The method of claim 1 , wherein the digital model base comprises an upper virtual base including a perimeter formed of a back side, a pair of oblique rear sides at opposite ends of the back side, a pair of front sides opposing the back side, and a pair of middle sides connecting the front sides to the rear sides.
7. The method of claim 1 , wherein the digital model base comprises a lower virtual base having a perimeter formed of a back side, a pair of oblique rear sides at opposite ends of the back side, a pair of middle sides opposing the back side and respectively connected at a first end of each of the middle sides to a respective oblique rear side, and a front curved side respectively connected to a second end of each of the middle sides, where the front curved side comprises an arc of a circle.
8. The method of claim 1 , wherein the local criteria of the second translation of the translated virtual base comprise local movement of selected points on each of rear sides, middle sides and front sides of the virtual base.
9. The method of claim 1 , wherein the digital model base comprises an upper virtual base or a lower virtual base, and wherein a dental frenulum is represented on the digital model base.
10. The method of claim 1 , wherein an operator instruction can adjust a portion of the digital model base.
11. The method of claim 1 , further comprising a step of adjusting each point of the surface of the virtual model base according to z scale displacement and local xy displacement.