Dental object detection method, and image matching method and device using dental object

1. An image registration method using a dental object, the method comprising:

generating a plurality of reference points spaced apart from each other in an oral scan image of a registration target and a computed tomography (CT) image of a registration target, respectively; and

registering the oral scan image of the registration target and the CT image of the registration target by using the reference point of the oral scan image (a first reference point) and the reference point of the CT image (a second reference point),

wherein the first and second reference points comprise a reference point for one frontmost tooth in the front teeth area and a reference point for two teeth on both rearmost sides of the back teeth area, and

wherein the first reference point is derived from an object which is a simplified shape of the teeth.

2. The method of claim 1 , wherein the generating the reference point comprises:

generating a learning model by training from training data that form an object for each tooth in multiple directions of the oral scan image of the learning target;

detecting an object for multiple directions of each tooth in the oral scan image of the registration target using the generated learning model; and

selecting a reference object from among the detected objects to generate a first reference point from the selected reference object.

3. The method of claim 1 , wherein the generating the reference point comprises:

generating a learning model by training with training data which form each object for n teeth (target tooth) (where n is a natural number equal to or greater than 3) spaced apart each other that are some teeth in multiple directions of the oral scan image of the learning target;

detecting an object for multiple directions of each target tooth in the oral scan image of the registration target using the generated learning model; and

selecting the detected object as a reference object to generate a first reference point from the selected reference object.

4. The method of claim 3 , wherein the reference object comprises an object for one frontmost tooth of the front teeth area, and an object for two teeth on both rearmost sides of the back teeth area.

5. The method of claim 3 , wherein the generating the reference point further comprises selecting a center point of the selected reference object as the first reference point.

6. An image registration apparatus comprising:

a storage for storing an oral scan image of a registration target and a computed tomography (CT) image of a registration target; and

a controllor for generating a plurality of reference points spaced apart from each other in the oral scan image and the CT image stored, respectively and then registering the oral scan image of the registration target and the CT image of the registration target by using the reference point of the oral scan image (a first reference point) and the reference point of the CT image (a second reference point),

wherein the first and second reference points comprise a reference point for one frontmost tooth in the front teeth area and a reference point for two teeth on both rearmost sides of the back teeth area, and

wherein the first reference point is derived from an object which is a simplified shape of the teeth.

7. The apparatus of claim 6 , wherein the controllor:

detects an object for multiple directions of each tooth in the oral scan image of the registration target using a learning model generated by training from training data that form an object for each tooth in multiple directions of the oral scan image and the CT image of the learning target, and then

selects a reference object from among the detected objects to generate a first reference point from the selected reference object.

8. The apparatus of claim 6 , wherein the controllor:

detects an object for multiple directions of each target tooth in the oral scan image of the registration target using a learning model generated by training with training data which form each object for n teeth (target tooth) (where n is a natural number equal to or greater than 3) spaced apart each other that are some teeth in multiple directions of the oral scan image and the CT image of the learning target; and then

selects the detected object as a reference object to generate a first reference point from the selected reference object.