Method for acquiring a dental object

Abstract

Disclosed herein is a method for acquiring a dental object of a patient with an object volume, in particular at least a part of a skull, an upper jaw and/or a lower jaw. To do so, a plurality of segment volume ranges are defined in the object volume, where the segment volume ranges overlap at most partially and directions of the segment volume ranges are not parallel to one another. The image data of the segment volume ranges is recorded by an MRI machine within a measuring volume of the MRI machine. A two-dimensional composite image is generated from the image data of the individual segment volume ranges by projecting the image data onto a target plane. The target plane is disposed parallel to a defined midsagittal plane of the skull or corresponds to the midsagittal plane, where a first segment volume range at least partially includes the midsagittal plane of the skull.

1 . Method for acquiring a dental object of a patient with an object volume, wherein a plurality of segment volume ranges are defined in the object volume, wherein the segment volume ranges overlap at most partially and directions of the segment volume ranges are not parallel to one another, wherein image data of the segment volume ranges is recorded by means of an MRI machine within a measuring volume of the MRI machine, wherein, computer-assisted, a two-dimensional composite image is generated from the image data of the individual segment volume ranges by projecting the image data onto a target plane, wherein the target plane is disposed parallel to a defined midsagittal plane of the object volume or corresponds to the midsagittal plane, wherein a first segment volume range at least partially comprises the midsagittal plane of the skull. 
     
     
         2 . Method according to  claim 1 , wherein a second segment volume range comprises at least a part of an upper jaw and/or a lower jaw, wherein the two-dimensional composite image is generated from the first segment volume range and the second segment volume range by projection onto the target plane. 
     
     
         3 . Method according to  claim 2 , wherein the second segment volume range comprises a left side of the upper jaw and/or the lower jaw, wherein additionally a third segment volume range comprises a right side of the upper jaw and/or the lower jaw, wherein the two-dimensional composite image is generated from the first segment volume range, the second segment volume range and the third segment volume range by projection onto the target plane. 
     
     
         4 . Method according to  claim 1 , wherein with respect to its position and orientation within the measuring volume of the MRI machine, each segment volume range is defined on the basis of a presetting for the respective patient or on the basis of a preliminary image of the object. 
     
     
         5 . Method according  claim 1 , wherein a depth of the segment volume ranges is between 0.5 mm and 30 mm. 
     
     
         6 . Method according to  claim 1 , wherein the composite image corresponds to a conventional cephalometric radiograph, wherein the target plane of the composite image corresponds to a plane which is disposed parallel to a detector surface of an X-ray detector for a cephalometric radiograph. 
     
     
         7 . Method according to  claim 1 , wherein the image data of the segment volume ranges is recorded by means of the MRI machine, in that a single three-dimensional MRI overall image of the dental object is recorded with the object volume, and the image data of the individual segment volume ranges is carried over from the three-dimensional MRI overall image. 
     
     
         8 . Method according to  claim 1 , wherein the image data of the segment volume ranges is recorded by means of the MRI machine, in that a plurality of MRI segment acquisitions, which display the defined segment volume ranges, are recorded by means of the MRI machine. 
     
     
         9 . Method according to  claim 8 , wherein the individual MRI segment acquisitions are incrementally measured by means of the MRI machine. 
     
     
         10 . Method according to  claim 8 , wherein at least two MRI segment acquisitions are measured at the same time by means of a special MRI machine based on a multislice excitation method. 
     
     
         11 . Method according to  claim 8 , wherein each MRI segment acquisition consists of a single MRI slice image or a stack of multiple MRI slice images, wherein the MRI slice images of a stack are arranged parallel to one another within the respective segment volume range. 
     
     
         12 . Method according to  claim 1 , wherein the midsagittal plane and/or the position and orientation of the individual segment volume ranges of the object volume are defined in that the patient is positioned relative to the MRI machine by a positioning device, or in that a preliminary image of the object volume of the patient is taken and the midsagittal plane is determined manually by a user or automatically by a computer on the basis of the preliminary image. 
     
     
         13 . Method according to  claim 1 , wherein the composite image is generated in a computer-assisted manner from the image data of the individual segment volume ranges by projection of the image data onto the target plane, in that the image data of the individual segment volume ranges is projected onto the target plane in a common projection direction, wherein the projection direction is arranged perpendicular to the target plane. 
     
     
         14 . Method according to  claim 1 , wherein, prior to the acquisition of the individual segment volume ranges in the object volume, the position and/or the orientation of the segment volume ranges in relation to the MRI machine are defined by a user, wherein a head template with an upper jaw template and/or a lower jaw template is schematically displayed by means of a display device, wherein the segment volume ranges and the arrangement thereof in relation to the head template and/or the target plane and/or the midsagittal plane are graphically displayed. 
     
     
         15 . Method according  claim 1 , wherein the generated composite image is displayed by means of a display device, wherein, in addition to the composite image, the image data of at least one segment volume range is displayed by means of the display device.