Reduction and removal of artifacts from a three-dimensional dental X-ray data set using surface scan information
A system for removing artifacts caused by x-ray reflective materials from an x-ray image of a patient's teeth. The system includes an x-ray source, an x-ray detector that captures several x-ray images, and a surface scanner that captures a surface scan of the patient's teeth. An image processor generates three-dimensional models from the optical surface data and the CT volumetric data. The models are resized and oriented to be of the same scale and orientation and then overlaid to create a combined data set. Data points that extend beyond the surface of the patient's teeth in the surface model are identified and may be removed if it is determined that they are artifacts. An artifact-reduced CT model is then displayed.
1. A system for removing artifacts caused by x-ray reflective materials from an x-ray image of a patient's teeth, the system comprising:
an x-ray source;
an x-ray detector that captures x-ray images;
a surface scanner that captures a surface scan of the patient's teeth; and
an image processor that constructs a three-dimensional CT model of the patient's teeth from the x-ray images and a three-dimensional surface model of the patient's teeth from the surface scan,
the image processor resizing and orienting at least one of the surface model and the CT model so that the surface model and the CT model are of a same scale and orientation,
overlaying the surface model on the CT model,
detecting data points in the combined data set that extend beyond a surface of the patient's teeth in the surface model, wherein the detected data points represent artifacts in the CT model,
removing the detected data points from the CT model by interpolation of the detected data points to create an artifact-reduced CT model, and
displaying the artifact-reduced CT model.
2. The system of claim 1 , wherein the surface scanner includes a laser scanning system.
3. The system of claim 1 , wherein the surface scanner includes a structured light scanning system.
4. The system of claim 1 , wherein the image processor determines that all data points in the combined data set that extend beyond the surface of the patient's teeth in the surface model are artifacts, and removes the artifacts from the CT model.
5. The system of claim 1 , wherein the image processor compares a value of data points in the combined data set that extend beyond the surface of the patient's teeth in the surface model to a threshold, determines whether the detected data points are artifacts based on the comparison, and removes the artifacts from the CT model.
6. The system of claim 1 , wherein the image processor performs a filtering operation on the data points in the combined data set that extend beyond the surface of the patient's teeth in the surface model, determines whether the detected data points are artifacts based on the filtering operation, and removes the artifacts from the CT model.
7. The system of claim 1 , wherein the image processor generates a first two-dimensional data slice from the surface model corresponding to a first two-dimensional data slice from the CT model, and detects data points in the combined data set that extend beyond a surface of the patient's teeth in the surface model by comparing the first two-dimensional data slice from the surface model to the first two-dimensional data slice from the CT model.
8. The system of claim 7 , wherein the first two-dimensional data slice from the surface model includes surface data for a first tooth.
9. The system of claim 8 , wherein the image processor generates a second two-dimensional data slice from the surface model including surface data for a second tooth and corresponding to a second two-dimensional data slice from the CT model after removing artifacts associated with the first tooth.
10. The system of claim 7 , wherein the first two-dimensional data slice from the surface model includes surface data for a plurality of teeth.
11. The system of claim 10 , wherein the image processor generates a second two-dimensional data slice from the surface model including data for the same plurality of teeth at a location parallel to the first two-dimensional data slice from the surface model and corresponding to a second two-dimensional data slice from the CT model after removing the artifacts associated with the first two-dimensional data slice from the CT model.
12. The system of claim 7 , wherein the first two-dimensional data slice from the surface model includes surface data for all of the patient's teeth.