Method for creating a three-dimensional digital model of a jaw.

Abstract

Method (100) for creating a three-dimensional digital model of a jaw, comprising the following steps: mounting (101) a transfer piece (10) on a fixing point of the dentition support, transversely to the extension plane of the dentition, a dimension of the transfer piece (10) along an extension direction (D) of the transfer piece (10) being less than a corresponding dimension of the teeth; acquiring (102) a digital recording of the maxilla and mandible in occlusal position (22), comprising the three-dimensional coordinates of points of the maxilla and mandible in occlusal position (22); registering (106) in the same reference frame the digital recording of the maxilla and mandible in occlusal position (22), from at least one point of the at least one transfer piece;construct (107) the digital model of the jaw by merging the registered digital recording of the maxilla and mandible in occlusal position. Figure 3;

Description

Title of the invention: Method for creating a three-dimensional digital model of a jaw.

[0001] The present invention relates to the field of methods for recording an intermaxillary relationship.

[0002] It is known to use optical sensors, for example using structured light, or based on photogrammetry, or sensors based on electromagnetic radiation, for example a sensor based on X-rays, to obtain a three-dimensional digital impression of a patient's dental arches. However, the use of these devices requires that the patient has a sufficiently complete dentition to allow him to obtain dental alignment and an appropriate occlusion position. If the dentition is not sufficiently complete, the use of a alignment piece is possible, but the digital recordings of the intermaxillary relationship obtained with known acquisition sensors are not sufficiently precise.

[0003] The invention therefore aims to propose a solution to all or part of these problems.

[0004] For this purpose, the present invention relates to a method for creating a three-dimensional digital model of a jaw comprising a mandible, and a maxilla, the mandible comprising a support for a lower dentition, the maxilla comprising a support for an upper dentition, at least a portion of the lower dentition and / or a portion of the upper dentition comprising at least one pre-positioned attachment point on the support of the lower dentition and / or on the support of the upper dentition, the mandible and the maxilla being articulated so that the mandible is rotatable about a temporomandibular joint to take an occlusal position in which an extension plane of the upper dentition and an extension plane of the lower dentition are located opposite each other on either side of an occlusal plane, the method comprising the following steps: - mounting at least one transfer piece on the at least one prepositioned fixing point of the lower dentition support and / or the upper dentition support, the at least one transfer piece being mounted projecting in a direction of extension of the transfer piece, said direction of extension being transverse to the plane of extension of the lower dentition, if the at least one transfer piece is mounted on the lower dentition support, or transverse to the plane of extension of the upper dentition if the at least one transfer piece is mounted on the upper dentition support the upper dentition, a dimension of the transfer piece along the direction of extension of the transfer piece being strictly less than a corresponding dimension of the teeth of the lower dentition, and / or of the upper dentition, the corresponding dimension being defined along a direction parallel to the direction of extension of the transfer piece; - implementing a first acquisition sensor to acquire a digital recording of the maxilla, the digital recording of the maxilla comprising the three-dimensional coordinates of a plurality of points of the maxilla; - implementing a second acquisition sensor to acquire a digital recording of the mandible, said digital recording of the mandible comprising the three-dimensional coordinates of a plurality of points of the mandible; - implementing a third acquisition sensor to acquire a digital recording of the maxilla and mandible in the occlusal position, said digital recording of the maxilla and mandible in the occlusal position comprising the three-dimensional coordinates of a plurality of points of the maxilla and mandible in the occlusal position; - identify on the digital recording of the mandible, and on the digital recording of the maxilla, and on the digital recording of the maxilla and the mandible in the occlusal position, at least one point of the at least one transfer piece mounted on the at least one pre-positioned fixing point of the lower dentition support and / or the upper dentition support; - using at least one point of the at least one transfer piece, re-align in the same reference frame the digital recording of the mandible, and the digital recording of the maxilla, and the digital recording of the maxilla and the mandible in the occlusal position; - construct the digital model of the jaw by merging the registered digital recording of the mandible, and the registered digital recording of the maxilla, and the registered digital recording of the maxilla and mandible in occlusion position.

[0005] According to these provisions, the transfer piece makes it possible to generate one or more reference points which are used for the registration of the digital recordings successively acquired in the different configurations of the jaw. The dimension of the transfer piece, strictly less than the corresponding dimension of a tooth of the patient, makes it possible to guarantee that the maxilla and the mandible can take the occlusion position, without risk of lateral sliding caused by contact between the transfer piece and a tooth of the opposite dentition. The dimension of the transfer piece, strictly less than the corresponding dimension of a tooth of the patient, also makes it possible to acquire points of a portion of the surface of the transfer piece, said portion of the surface being located at an end opposite the fixing point pre-positioned on the support.

[0006] According to one embodiment, the invention comprises one or more of the following characteristics, alone or in a technically acceptable combination.

[0007] According to one embodiment, the first acquisition sensor, the second acquisition sensor and the third acquisition sensor are identical.

[0008] According to one embodiment, the first acquisition sensor, and / or the second acquisition sensor, and / or the third acquisition sensor is an optical photogrammetry device, or a radiography device, for example using X-rays.

[0009] According to one embodiment, the at least one pre-positioned attachment point is an implant.

[0010] According to one embodiment, the lower dentition and / or the upper dentition further comprises at least one tooth, occlusal wedging of the mandible and the maxilla in the occlusion position being impossible due to a positioning of the at least one tooth on the support of the lower dentition relative to a positioning of the at least one tooth on the support of the upper dentition, the method further comprising a step of placing a wedging piece configured to be interposed between the support of the lower dentition and the support of the upper dentition when the mandible and the maxilla are in the occlusion position, the placement step being carried out before the step of implementing the third acquisition sensor to acquire a digital recording of the maxilla and the mandible in the occlusion position.

[0011] According to these provisions, the wedging part allows occlusal wedging before the implementation of the third acquisition sensor to acquire a digital recording of the maxilla and the mandible in the occlusal position.

[0012] According to one embodiment, the wedging part is made of resin, or silicone, or metal.

[0013] According to one embodiment, the wedging part comprises at least one partially hollowed-out portion interposed between two wedging parts, the at least one partially hollowed-out portion being configured to allow the at least one transfer part mounted on the support of the lower dentition and / or on the support of the upper dentition to pass through, the dimension of the transfer part in the direction of extension of the transfer part being less than a thickness of the wedging parts of the wedging part in the direction of extension of the transfer part.

[0014] According to one embodiment, the transfer part is made of a material opaque to X-rays.

[0015] According to these provisions, the transfer part is adapted for the use of an X-ray device for the acquisition of digital recordings. successive.

[0016] According to one embodiment, the transfer part is made of a metallic material, or of a plastic material, for example of the PEEK or POM type.

[0017] According to these provisions, the transfer part is adapted for the use of an optical photogrammetry device for the acquisition of successive digital recordings.

[0018] According to one embodiment, the transfer part comprises an external surface with at least a portion of the surface defining an angular edge, or an angular point, with at least one other portion of the surface.

[0019] According to these provisions, the reference points on the transfer part will be easier to identify in the digital recordings.

[0020] According to one embodiment, the external surface of the transfer part has a shape having a symmetry of revolution around the direction of extension of the transfer part. Thus when the transfer part must be removed then replaced between two successive digital recording acquisitions, its angular position around the direction of extension will be indifferent; it will therefore be easier to find the initial angular position.

[0021] According to these provisions, the reference points on the transfer part which correspond from one digital recording to another will be fewer in number, but more easily identifiable; the lower number of reference points per transfer part can be compensated for, if the number of transfer parts is greater.

[0022] For a better understanding, an embodiment and / or implementation of the invention is described with reference to the attached drawings representing, by way of non-limiting example, an embodiment or implementation respectively of a device and / or a method according to the invention. The same references in the drawings designate similar elements or elements whose functions are similar.

[0023] [Fig. 1] is a perspective view of an exemplary embodiment of a transfer part used in the method according to the invention

[0024] [Fig.2] is a perspective view of a used shimming piece, complementing silently to the transfer part, in the method according to the invention

[0025] [Fig.3] is a diagram of the sequence of steps of the method according to the invention

[0026] [Fig.4] is a perspective representation of a digital recording of a maxilla provided with transfer pieces according to the invention and a digital recording of a mandible provided with dentition.

[0027] [Fig.5] is a perspective representation of a digital recording of a maxilla and mandible in occlusion position, with a wedging piece.

[0028] The method 100 according to the invention aims at creating a three-dimensional digital model of a jaw.

[0029] The jaw comprises, as is known, a mandible, and a maxilla, the mandible comprising a support for a lower dentition, the maxilla comprising a support for an upper dentition.

[0030] When the dentition is incomplete, at least a part of the lower dentition and / or a part of the upper dentition, comprises at least one prepositioned fixing point, for example an implant, on the support of the lower dentition and / or on the support of the upper dentition.

[0031] It is important to note that the pre-positioning of the fixation point, for example of the implant, is not part of the method according to the present invention. The pre-positioning of the fixation point, for example of the implant, is carried out before and outside the method according to the present invention. Thus, the method according to the invention does not include a surgical intervention step on the jaw of a patient.

[0032] The mandible and the maxilla are articulated so that the mandible is rotatable about a temporomandibular joint, to take an occlusal position in which an extension plane of the upper dentition and an extension plane of the lower dentition are located opposite each other on either side of an occlusal plane.

[0033] The method 100 according to the present invention comprises the following steps, with reference to Figures 1 and 3: - mounting 101 one or more transfer part(s) 10 on one or more of the pre-positioned fixing point(s) on the support of the lower dentition and / or on the support of the upper dentition; each transfer part 10 is mounted projecting in a direction of extension D of the transfer part 10, said direction of extension D being transverse to the plane of extension of the lower dentition if the at least one transfer part 10 is mounted on the support of the lower dentition, or transverse to the plane of extension of the upper dentition if the at least one transfer part 10 is mounted on the support of the upper dentition.

[0034] An exemplary embodiment of a transfer part 10 according to the invention is shown in [Fig. 3]. Thus, for example, the transfer part 10 may be tubular, with at one end an interface for fixing to the pre-positioned fixing point, for example the implant; the fixing interface may be, for example, a threaded hole configured to be screwed onto a corresponding threaded member of the fixing point.

[0035] A dimension of the transfer part 10 along the direction of extension D of the transfer part 10 is strictly less than a corresponding dimension of the teeth of the lower dentition, and / or of the upper dentition, the corresponding dimension being defined along a direction parallel to the direction of extension D of the transfer part 10. transfer 10; according to this particular arrangement, the occlusion position can be taken by the jaw. According to these arrangements, the dimension of the transfer piece, strictly less than the corresponding dimension of a tooth of the patient, makes it possible to guarantee that the maxilla and the mandible can take the occlusion position, without risk of lateral sliding caused by contact between the transfer piece and a tooth of the opposite dentition. The dimension of the transfer piece, strictly less than the corresponding dimension of a tooth of the patient, also makes it possible to acquire points of a portion of the surface of the transfer piece, said portion of the surface being located at an end opposite to the pre-positioned fixation point on the support.

[0036] Once the transfer part(s) 10 are mounted on the pre-positioned fixing point(s), the following steps of the method 100 can be implemented:

[0037] - implement 102 a first acquisition sensor to acquire a recording digital recording of the maxilla 20, the digital recording of the maxilla 20 comprising the three-dimensional coordinates of a plurality of points of the maxilla; an example of a digital recording of the maxilla is presented in [Fig.4], in which the surfaces of the organs of the maxilla and the transfer parts are reconstructed from the plurality of points acquired by the first acquisition sensor. - implementing 103 a second acquisition sensor to acquire a digital recording of the mandible 21, said digital recording of the mandible 21 comprising the three-dimensional coordinates of a plurality of points of the mandible; an example of a digital recording of a mandible forming a jaw with the maxilla of [Fig.4], is also presented in [Fig.4], in which the surfaces of the organs of the mandible are reconstructed from the plurality of points acquired by the second acquisition sensor. - implementing 104 a third acquisition sensor to acquire a digital recording of the maxilla and the mandible in the occlusion position 22, said digital recording of the maxilla and the mandible in the occlusion position 22 comprising the three-dimensional coordinates of a plurality of points of the maxilla and the mandible in the occlusion position; an example of a digital recording 22 of the maxilla of [Fig.4] and of the mandible of [Fig.4], in the occlusion position, is presented in [Fig.5], in which the surfaces of the jaw organs, of the transfer parts 10, are reconstructed from the plurality of points acquired by the third acquisition sensor. - identify 105 on the digital recording of the mandible, and on the digital recording of the maxilla, and on the digital recording of the maxilla and the mandible in occlusion position, at least one point of the at least one transfer piece mounted on the at least one pre-positioned fixing point of the lower dentition support and / or the upper dentition support; - using at least one point of the at least one transfer part, re-align (106) in the same reference frame the digital recording of the mandible, and the digital recording of the maxilla, and the digital recording of the maxilla and the mandible in the occlusion position; - construct 107 the digital model of the jaw by merging the registered digital recording of the mandible, and the registered digital recording of the maxilla, and the registered digital recording of the maxilla and mandible in occlusion position.

[0038] According to these provisions, the transfer part makes it possible to generate one or more reference points used for the recalibration of the digital recordings successively acquired in the different configurations of the jaw.

[0039] In particular, the first acquisition sensor, the second acquisition sensor, and the third acquisition sensor may be identical.

[0040] In a manner known to those skilled in the art, the first acquisition sensor, and / or the second acquisition sensor, and / or the third acquisition sensor is an optical photogrammetry device, or a radiography device, for example X-ray.

[0041] The transfer part may be made of a material opaque to X-rays, to be suitable for the use of an X-ray radiography device. The transfer part may be made of a metallic material, or of a plastic material, for example of the PEEK or POM type, to be suitable for the use of an optical photogrammetry device.

[0042] Advantageously, an external surface of the transfer part 10 comprises one or more facets or surface portions each defining, with one or more other surface portions, edges or angular points, which will promote the generation of reference points in the digital recordings acquired in the steps of implementing the acquisition sensor, the three-dimensional coordinates of said reference points then being determined with more precision, promoting more precise registration of the different digital recordings acquired by the acquisition sensor. In the absence of specific markers on the surface of the transfer part, for example when the transfer part has the shape of a simple cylinder, precise registration can nevertheless be obtained with the use of several transfer parts 10.

[0043] According to an example of implementation of the method 100 according to the invention, when the lower dentition and / or the upper dentition comprises a certain number of teeth, and when a positioning of the teeth present on the support of the lower dentition relative to the positioning of the teeth present on the support of the upper dentition does not allow appropriate occlusal wedging so that the maxilla and the mandible can take the desired occlusal position, then the use of a wedging piece 11 can be envisaged to allow occlusal wedging of the maxilla and the mandible in the occlusal position, as illustrated in [Fig.2].

[0044] The method then comprises a step 104bis of placing a wedging piece 11 configured to be interposed between the support of the lower dentition and the support of the upper dentition when the mandible and the maxilla are in the occlusion position, the placement step being carried out before the step 104 of implementing the acquisition sensor to acquire a digital recording of the maxilla and the mandible in the occlusion position.

[0045] The wedging part 11 is for example made of resin, or silicone, or metal.

[0046] In particular, as illustrated in [Fig.2], the wedging part 11 can comprise at least one partially hollowed-out portion 11'” interposed between two wedging portions 11', 11”, the at least one partially hollowed-out portion 11'” being configured to allow the at least one transfer piece 10 mounted on the support of the lower dentition and / or on the support of the upper dentition to pass through, the dimension of the transfer piece 10 in the direction of extension of the transfer piece being less than a thickness of the wedging portions 11', 11” of the wedging piece 11 in the direction of extension of the transfer piece.

[0047] An example of digital recording 22 of the maxilla of [Fig.4] and the mandible of [Fig.4], in the occlusion position, with the wedging piece 11, is presented in [Fig.5], in which the surfaces of the jaw organs, the transfer pieces 10, and the wedging piece 11, are reconstructed from the plurality of points acquired by the third acquisition sensor.

Claims

Claims

1. Method (100) for creating a three-dimensional digital model of a jaw comprising a mandible, and a maxilla, the mandible comprising a support for a lower dentition, the maxilla comprising a support for an upper dentition, at least a portion of the lower dentition and / or a portion of the upper dentition comprising at least one pre-positioned attachment point on the support of the lower dentition and / or on the support of the upper dentition, the mandible and the maxilla being articulated so that the mandible is rotatable about a temporomandibular joint to assume an occlusion position in which an extension plane of the upper dentition and an extension plane of the lower dentition are located opposite each other on either side of an occlusion plane, the method (100) comprising the following steps: - mounting (101) at least one transfer part (10) on the at least one pre-positioned fixing point of the lower dentition support and / or the upper dentition support, the at least one transfer part (10) being mounted projecting in a direction of extension (D) of the transfer part (10), said direction of extension (D) being transverse to the plane of extension of the lower dentition, if the at least one transfer part (10) is mounted on the lower dentition support, or transverse to the plane of extension of the upper dentition if the at least one transfer part (10) is mounted on the upper dentition support, a dimension of the transfer part (10) in the direction of extension (D) of the transfer part (10) being strictly less than a corresponding dimension of the teeth of the lower dentition, and / or of the upper dentition,the corresponding dimension being defined in a direction parallel to the direction of extension (D) of the transfer part (10);, - implementing (102) a first acquisition sensor to acquire a digital recording of the maxilla (20), the digital recording of the maxilla comprising the three-dimensional coordinates of a plurality of points of the maxilla; - implementing (103) a second acquisition sensor to acquire a digital recording of the mandible (21), said digital recording of the mandible comprising the three-dimensional coordinates

2.

3. mensionals of a plurality of points of the mandible; - implementing (104) a third acquisition sensor to acquire a digital recording of the maxilla and mandible in the occlusion position (22), said digital recording of the maxilla and mandible in the occlusion position comprising the three-dimensional coordinates of a plurality of points of the maxilla and mandible in the occlusion position; - identify (105) on the digital recording of the mandible, and on the digital recording of the maxilla, and on the digital recording of the maxilla and the mandible in the occlusion position, at least one point of the at least one transfer piece mounted on the at least one pre-positioned fixing point of the lower dentition support and / or the upper dentition support; - using at least one point of the at least one transfer part, re-align (106) in the same reference frame the digital recording of the mandible, and the digital recording of the maxilla, and the digital recording of the maxilla and the mandible in the occlusion position; - construct (107) the digital model of the jaw by merging the readjusted digital recording of the mandible, and the readjusted digital recording of the maxilla, and the readjusted digital recording of the maxilla and mandible in occlusion position. Method according to claim 1, in which the lower dentition and / or the upper dentition further comprises at least one tooth, occlusal wedging of the mandible and the maxilla in the occlusion position being impossible due to a positioning of the at least one tooth on the support of the lower dentition relative to a positioning of the at least one tooth on the support of the upper dentition, the method further comprising a step of placing (104bis) a wedging piece (11) configured to be interposed between the support of the lower dentition and the support of the upper dentition when the mandible and the maxilla are in the occlusion position, the placement step being carried out before the step of implementing (104) the third acquisition sensor to acquire a digital recording of the maxilla and the mandible in the occlusion position;. Method according to claim 2, in which the wedging part (11) comprises at least one partially hollowed out part (11”) interposed between two wedging parts (11’, 11”), the at least one part- partially hollowed out (11”') being configured to allow the at least one transfer part (10) mounted on the support of the lower dentition and / or on the support of the upper dentition to pass through, the dimension of the transfer part (10) in the direction of extension (D) of the transfer part (10) being less than a thickness of the wedging parts (11', 11”) of the wedging part (11) in the direction of extension (D) of the transfer part (10).

4. Method according to one of the preceding claims, in which the transfer part (10) is made of a material opaque to X-rays.

5. Method according to one of the preceding claims, in which the transfer part (10) is made of a metallic material, or of a plastic material, for example of the PEEK or POM type.

6. A method according to any preceding claim, wherein the transfer part (10) comprises an outer surface with at least a portion of the surface defining an angular edge, or an angular point, with at least one other portion of the surface.

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