Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
  • A61C7/002—Orthodontic computer assisted systems
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C5/00—Filling or capping teeth
  • A61C5/007—Dental splints; teeth or jaw immobilisation devices; stabilizing retainers bonded to teeth after orthodontic treatments
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
  • A61C7/12—Brackets; Arch wires; Combinations thereof; Accessories therefor
  • A61C7/14—Brackets; Fixing brackets to teeth
  • A61C7/145—Lingual brackets
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
  • A61C7/12—Brackets; Arch wires; Combinations thereof; Accessories therefor
  • A61C7/14—Brackets; Fixing brackets to teeth
  • A61C7/146—Positioning or placement of brackets; Tools therefor
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
  • A61C7/12—Brackets; Arch wires; Combinations thereof; Accessories therefor
  • A61C7/14—Brackets; Fixing brackets to teeth
  • A61C7/16—Brackets; Fixing brackets to teeth specially adapted to be cemented to teeth

Definitions

• the present invention relates to the field of orthodontics, and more specifically to the field of fixed orthodontic retention systems, intra-oral and intended to be applied, but not exclusively, to the lingual surface of the teeth.
• the retention device then has the function of providing sufficient rigidity to hold the teeth in position, while providing appropriate flexibility so that the teeth retain freedom of movement relative to each other.
• the teeth have a certain natural mobility allowing them to absorb the mechanical physical stresses, in particular during chewing.
• the retention device must therefore allow controlled mobility between the teeth.
• removable restraint devices worn mainly at night.
• the effectiveness of removable devices depends on patient cooperation and attendance, and frequent oversights impair effectiveness.
• Fixed retainers are mainly intra-oral, and consist of fixing to the teeth, preferably on their non-visible lingual face, a retainer element having the required rigidity characteristics.
• the contention element can be a particular metal splint, for example cast and bonded to the lingual face of the teeth.
• the high rigidity of this solution may cause the metal splint to come off when chewed.
• irreversible mutilation of the teeth is necessary in order to provide a space on the teeth corresponding to the thickness of the material forming the bar and to limit discomfort in the mouth.
• Another solution consists of using a wire-type restraint element, generally a braided multi-strand steel wire of circular section, of suitable length to provide restraint on a determined number of teeth.
• a specialist then shapes the wire, either directly on the lingual surface of the patient's teeth, or in the laboratory on a model of the patient's teeth, so that the wire presses against the lingual surface of the teeth as much as possible.
• the wire is then glued using composite resin pads on the teeth.
• the wire can be replaced by a metal chain, a wire of rectangular section, or a strip of fiberglass.
• the floss can be completely embedded in resin to hold it against the teeth. [10]
• the thickness of the resin must make it possible to coat the contention element, provide sufficient mechanical strength and limit discomfort in the mouth.
• the thickness of the resin influences to varying degrees the comfort of the patient, the ease of cleaning and the risk of discomfort when chewing which can lead to the detachment of the contention element and an emergency consultation with a specialist.
• the retainer is a wire
• the complex bending of the latter in order to press it against the teeth increases the risk that the wire does not perfectly follow the lingual surface of each tooth, as well as the boundary between two neighboring teeth. More specifically, the wire, locally straight, may not follow the double convexity of the dental surfaces and creates a relief that is a source of discomfort for the patient and difficulty in cleaning.
• a first object of the invention is to propose a solution for a dental retainer intended to remain in the mouth continuously, with great comfort for the patient.
• a second object of the invention is to provide a solution for robust dental retention, which does not break during the patient's daily activities.
• a third object of the invention is to provide a solution for dental retention that is easy to maintain, guaranteeing good hygiene.
• a fourth object is to propose a solution for a dental retainer that is easily installed in the mouth, with a limited number of operations in the patient's mouth, limiting the time spent installing the retainer and increasing its comfort.
• a fifth object is to provide personalized dental retention for the patient, perfectly adapted to the anatomical characteristics of the patient.
• the invention relates to an orthodontic retention device comprising at least a first rigid plate and a second rigid plate.
• Each wafer comprising an internal face intended to be fixed rigidly to a tooth of a patient and an opposite external face.
• the compression device further comprises at least one articulated connection element connecting the first pad and the second pad, each pad comprising on its outer face a place of attachment for the articulated connection element.
• the connecting element is shaped to correspond to a portion of dental surface extending between the first wafer and the second wafer.
• the connecting element can thus be applied against the corresponding dental surface portion, extending between the two rigid pads, to provide intimate contact and thereby effective and comfortable restraint.
• the pads can be very thin, and the connecting element follows a curvature, a fold, which is not felt by the patient at the transition between an insert and a tooth.
• Each connecting element can be fixed to the outer face of the corresponding wafer by welding, the welding guaranteeing mechanical continuity of the connection. In addition, welding makes it possible to provide quality fixing, with good mechanical strength, and limiting discomfort in the mouth. Welding should be understood here as encompassing both welding strictly speaking and brazing.
• the pads are preferably made of metal or metal alloy, in particular to allow welding according to various known techniques.
• the articulated connecting element is for example of the wire type, that is to say it has two very small dimensions compared to the third, called length. It thus allows it to be deformed and shaped to be applied as close as possible to the corresponding dental surface, while limiting the size in the mouth. It is for example multi-stranded or single-stranded.
• the device may comprise at least a third rigid wafer, the inner face of which is intended to be rigidly fixed to a tooth of the patient between the first wafer and the second wafer.
• the articulated connecting element is then also fixed to at least one fixing location on the external face of the third plate.
• the articulated connecting element may comprise at least two distinct portions.
• the third plate can then comprise two distinct and separate attachment locations, and a first portion of the articulated connecting element is attached on the one hand to the attachment location of the first plate and on the other hand to an attachment location of the third plate.
• the second portion of the articulated connecting element is fixed on the one hand to the other place of fixing of the third wafer and on the other hand to the place of fixing of the second wafer.
• the portions of the articulated connecting element thus individualized bend more easily in order to conform as closely as possible to the dental surface against which they are intended to be applied
• the invention relates to a system for placing an orthodontic retention device, the device comprising at least a first rigid plate and a second rigid plate, each plate comprising an internal face intended to be rigidly fixed to a tooth of a patient and an opposite external face, the retention device further comprising at least one articulated connecting element connecting the first plate and the second plate, each plate comprising directly on its external face a place of fixation for the articulated connecting element, the connecting element being shaped to correspond to a portion of dental surface extending between the first wafer and the second wafer.
• the implementation system then comprising in particular: at least a first rigid wafer and a second rigid wafer, each wafer comprising an internal face intended to be rigidly fixed to a tooth of a patient and an opposite external face, each wafer comprising on its external face a place of fixation for the articulated link element; - At least one so-called rigid connecting element between the pads, the rigid connecting element being more rigid than the articulated connecting element; at least one guide assembly for positioning the articulated connection element, the guide assembly for positioning the articulated connection element being physically separated from the pads, the guide assembly for positioning the articulated connection element comprising at least one guide extending between the two pads and being connected to the pads by the rigid connecting element, the guide being a model representing the portion of dental surface extending between the two pads.
• the rigid link element and the positioning guide assembly of the articulated link element are also intended to be removed once the pads are rigidly attached to the teeth of a patient.
• the system thus makes it possible to easily but accurately position the retention device so that the articulated connecting element best corresponds to the portion of the dental surface against which it is intended to be applied.
• the articulated connecting element can be shaped outside of the patient's mouth. This shaping can be done with increased precision compared to shaping in the mouth, and with greater comfort for the patient.
• the positioning system reduces the intervention time on the patient to install the device, again increasing its comfort.
• the great precision with which the articulated retention element is placed, in intimate contact with the corresponding dental surface ensures effective and robust retention.
• the system may further comprise at least one guide assembly for the individual positioning of the wafers.
• the guide assembly for the individual positioning of the inserts can then comprise at least one reference surface complementary to at least one surface portion of a corresponding tooth, the reference surface being capable of being applied against the corresponding tooth in order to the pads in a determined position on all the teeth concerned.
• the Individual Pad Positioning Guide Assembly is intended to be removed once the pads are rigidly attached to a patient's teeth.
• the guide assembly for the individual positioning of the wafers can comprise as many reference surfaces as there are wafers, each surface reference being associated with the placement of a platelet and being complementary to at least one surface portion of the tooth on which the associated platelet is intended to be fixed.
• the shape and position of the pads can thus be determined before installation in the mouth in an optimal manner, in particular taking into account comfort in the mouth.
• the pads are then perfectly positioned on each tooth thanks to this guide assembly.
• the articulated retention element is placed as close as possible to the corresponding surface of the teeth, following the shape of this surface in intimate contact, for the comfort of the patient, and effective and robust retention.
• the invention relates to a method for manufacturing a custom-made orthodontic retention device as presented above, the method comprising: the generation of a model comprising the lingual face of at least one dental arch of a patient; - from the model of the dental arch, the determination of a personalized model of the orthodontic retention device comprising the shape and position of the pads and of the articulated connecting element, from the model of the orthodontic retention device, the manufacture of a system for placing an orthodontic retention device as presented above; the manufacture of the at least one articulated connection element by application against the guide of the guide assembly to the positioning of the articulated connection element (4); the fixing of the articulated connection elements on the places of fixing of the pads.
• the guide assembly for positioning the articulated connecting element is removed.
• the placement system can then be installed in the mouth with the articulated retainer already shaped.
• the generation of a model of at least one dental arch of a patient comprises the generation of a three-dimensional digital model of the dental arch, in order to automate the following steps.
• the system for placing an orthodontic retention device is produced by additive manufacturing, which in particular makes it possible to manufacture at a lower cost.
• FIG. 1 is a diagram of an embodiment of a retention device installed on the lingual surface of teeth in a mandibular arch.
• FIG. 2 represents a digital model of two dental arches of a patient, the arches being in occlusion, on which extreme limit curves are identified.
• FIG. 3 represents the model of figure 2, on which a shrinkage with respect to each extreme limit curve is represented in broken lines
• FIG. 4 depicts the model of Figure 3, in which regions for pad attachment of the retainer of Figure 1 are identified.
• FIG. 5 represents the model of FIGS. 2, 3 and 4, on which number plates are positioned.
• FIG. 6 represents part of a system for fitting the restraint device of FIG. 1, according to one embodiment.
• FIG. 7 represents a completed part of the system of figure 6.
• FIG. 8 represents an even more complete part of the system of FIG. 7.
• FIG. 9 represents the complete installation system of FIG. 6.
• the invention relates to a device 1 for orthodontic retention, and of which an example of an embodiment in accordance with the invention is shown in FIG. 1, placed on the lingual surface of the teeth of the dental arch bottom of a patient.
• the device 1 comprises at least two plates 2 rigid. According to a preferred embodiment, the device 1 can comprise as many pads 2 as there are teeth affected by the retainer. According to the example of figure 1, six teeth are concerned, so that the device 1 of contention comprises six pads 2.
• each wafer 2 is one-piece, and comprises an internal face complementary to the lingual morphology of the tooth concerned, possibly machined with micro-patterns to promote the retention of the bonding material, and a face 3 external which is smooth before fixing connecting elements.
• smooth is meant here the absence of asperity on the outer surface 3 which is detectable by the patient once the wafer has been placed in the mouth, in particular using the tongue.
• the external surface 3 is the face opposite the internal face which is closest to it, that is to say for example that the external surface 3 is not formed on an extra thickness or on an element added on the wafer 2.
• the thickness of the wafer 2 thus corresponds to the average distance between the internal surface and the external surface 3.
• Plates 2 are connected by at least one element 40 of articulated connection.
• the articulated connection element 40 is preferably of the wire type, that is to say it comprises two dimensions of the same order of magnitude and which are very small compared to a third dimension, called the length.
• the articulated connection element 40 can comprise a single portion, fixed to and connecting all of the plates 2, or comprise several portions 4 of articulated connection.
• each portion 4 of articulated connection extends between two pads 2 of two adjacent teeth, and extends between two extreme portions 4a, 4b.
• the six plates 2 are connected by five portions 4 of articulated connection.
• the articulated connection element 40 can be a multi-strand or single-strand wire, of any section.
• N pads 2 are required to which correspond N-1 portions 4 of articulated connection.
• Each plate 2 comprises, directly on its outer face 3, at least one place 5 of attachment for an end portion 4a, 4b of a portion 4 of the element 40 of articulated connection.
• the two pads 2 located at the ends of the device 1 for restraint each comprise a single location 5 of attachment, while the other pads 2 of the device 1 for restraint each comprise two locations 5 of attachment.
• the two places 5 of fixing are distinct and physically separated from each other, that is to say that a portion 4 of articulated connection fixed on a first place 5 for fixing a wafer 2 has no interaction or direct contact with another portion 4 of articulated connection fixed to the second place 5 for fixing this same wafer 2.
• each plate 2 may comprise a single place 5 of fixing on which the element 40 of articulated connection is fixed.
• Each place 5 for fixing a wafer 2 is located on the outer surface 3, that is to say that it is not formed in the thickness of the wafer 2, which can then have a reduced thickness down to a so-called material resistance thickness, that is to say a minimum thickness to obtain the required rigidity, and thus offers in particular greater comfort for the patient.
• a so-called material resistance thickness that is to say a minimum thickness to obtain the required rigidity, and thus offers in particular greater comfort for the patient.
• to fix an articulated connection portion 4 on a plate 2 it is applied against the external surface 3, and forms an extra thickness on the external surface 3 of the plate 2.
• a first end part 4a of an articulated connection portion 4 is fixed to a location 5 of attachment on the outer surface 3 of a first plate 2 and the second end part 4b of this articulated connection portion 4 is fixed on the outer surface 3 on a place 5 for fixing a second wafer 2.
• the articulated connecting element 40 can thus be as close as possible to the portion of dental surface between each wafer 2. Indeed, in particular thanks to the place of attachment directly on the outer face 3 which allows a small thickness of the platelets 2, the articulated connecting element 40 follows a change in curvature at the transition between a platelet and the dental surface which is soft, almost undetectable by the patient once the device is placed in the mouth.
• the articulated connection element 40 can be metallic or metallic alloy.
• Plates 2 can also be metallic or made of metallic alloy. The fixing of an end part 4a or 4b of an articulated connection portion 4 on the external face 3 of a plate 2 can then be carried out by welding.
• the invention is not limited to platelets 2 and metal articulated connecting elements 40, and other materials, such as ceramic in particular for the platelets 2, or any other material used in orthodontics, are conceivable.
• the articulated connection element 40 is made in several individualized portions 4 between two pads 2, it is then more easily deformable, and thus allows it to be applied with increased precision against the corresponding dental surface portion, c that is to say, for example against the portion of the lingual face of the teeth located between two adjacent pads 2, but also against a portion of the outer surface 3 of the pads 2 on which it is fixed.
• each portion 4 of articulated connection extends, by definition, astride at least two teeth.
• each portion 4 of articulated connection must be in intimate contact with the corresponding dental surface portion, that is to say that each portion must be able to follow the changes in curvature of the dental surface, and in particular the sudden change in curvature at the junction between two teeth.
• each articulated connection portion 4 in order to provide adequate comfort to the patient, must also follow the change in curvature between each insert 2 and the tooth on which the insert 2 is fixed.
• the place 5 for fixing the extreme parts 4a, 4b of the articulated connection portions 4 on the outer surface 3 of the pads 2 also contributes to making the articulated connection portions 4 deformable more easily.
• this makes it possible to have platelets 2 of small thickness, and therefore to have a change in curvature between the platelets 2 and the teeth which is small, non-obtrusive because it is almost undetectable by the patient once the device is in the mouth. .
• the restraint device 1 thus offers optimal restraint, and great comfort for the patient thanks to the elasticity of the articulated connecting element 40, which in particular accompanies the natural movement of the teeth while maintaining the restraint, and thanks to the places 5 of attachment on the outer surface 3 of the pads 2 which allow the pads 2 to be of minimum thickness.
• the pads 2 and the articulated connection element 40 can be designed individually for each patient, in particular according to the place in the mouth.
• a patient's dental arches can be scanned by any technique.
• a preliminary step then consists of digitally acquiring the data necessary to obtain a digital model.
• an impression is made in the conventional manner, in order to make a mold and cast a plaster model. The plaster model of each arch is then digitized separately, and occlusion is performed digitally.
• Figures 2 to 5 schematically show different stages of an embodiment of determining the place of attachment and the shape of the pads 2.
• the digital, virtual model, resulting from the data acquisition stage corresponds to the three-dimensional surface visible in lingual view of the two arches of the patient, placed in occlusion, in order to take into account any possible discomfort during the occlusion.
• extreme limit curves are identified on the digital model. These curves can correspond: to typical discontinuities, such as those of the border between teeth and gum, and the border between two adjacent teeth; to changes in curvatures, of different quantitative and qualitative categories, which make it possible to identify the limits of the lingual surfaces of each tooth.
• An example of the identification of the horizontal limit curves is represented in figure 2.
• the line 6 of the upper collars and the line 7 of the lower collars which correspond respectively to the curved limit of the border between the gum and respectively each tooth of the upper arch and each tooth of the lower arch, can be identified by the discontinuity greater than a simple change in curvature at the level of the three-dimensional surface, and the difference in the surface finish between a tooth and the gum.
• Line 8 of the occlusal limits formed by the apices of the cusps and the free edges of the mandibular incisors can be identified by the appearance of changes in curvature beyond a threshold.
• Two bands can then be defined: an upper band between the line 6 of the upper collars and the line 8 of the occlusal limits, and a lower band between the line 8 of the occlusal limits and the line 7 of the lower collars.
• a setback in relation to limit curves 6, 7 and 8 can be defined. This is, for example, a safety margin distance which can be defined by the practitioner (broken lines visible in figures 3 and 4).
• Digital 2' pads can then be placed on the digital model.
• a digital plate 2' materializes the surface which will be occupied by the plate 2 when it is attached to the tooth.
• the plates 2 have an overall quadrilateral shape with a trapezium tendency.
• digital preforms which correspond to models linked to different morphologies linked to dental type (canines, maxillary incisors, mandibular incisors), taken from a database for example, to be centered and projected onto the region 10 previously determined, for each tooth.
• a plot of the outline of the pads 2, forming digital pads 2' can thus be produced automatically, from the limits of the regions 10, and possibly with adjustment by the practitioner.
• the practitioner can intervene at each stage of the determination of the regions 10 and the shape of the digital plates 2'.
• it can be envisaged to allow the practitioner to correct or modify the curves 6, 7 horizontal limits and the curves 9 vertical limits, and/or to adjust the setbacks.
• the internal face of the pads 2 can also be determined from the digital pads 2' to be perfectly complementary, in a personalized manner, to the lingual face of the tooth concerned for the patient, or to be complementary to a model for the corresponding tooth.
• the inserts 2 are then designed by extrusion from the digital inserts 2', by determining a minimum thickness called the resistance of the material.
• the pads 2 may have all or part of the edges which are bevelled, avoiding protruding edges which could injure and/or inconvenience the patient.
• the restraint device 1 can thus be placed on the teeth of the maxilla by limiting the risk of discomfort from a pad 2 with a lower canine in occlusion, as well as on the teeth of the mandible.
• the stability of the position of the platelets 2 once the device 1 has been placed in the mouth is thus improved, thereby increasing the stability of the result of the orthodontic retainer.
• This optimization can also be done directly by the practitioner, without necessarily going through automatic modeling.
• the digital preforms of the inserts 2 can be directly centered and projected onto a model, real or digital, of the lingual face of each tooth, the practitioner making the adjustments he considers necessary by eye.
• a system 11 for fitting an orthodontic retention device, particularly suitable for the placement of the retention device 1 comprising the individualized articulated connection elements 4.
• the system 11 thus comprises: at least two rigid pads 2, which are the pads 2 of the restraint device 1, at least one so-called rigid connecting element 12 between the pads 2, that is to say an element ensuring the connection between the plates 2 to keep them in a determined position relative to each other.
• the connecting element 12 is said to be rigid, that is to say that it is more rigid than the articulated connecting element 40 of the restraint device 1. In other words, the force to be exerted on the connecting element 12 in order to move the plates 2 relative to each other is greater than the force to be exerted on the articulated connecting element 40 for the same movement. .
• the rigidity of the rigid connecting element 12 is such that it does not allow any movement of the pads 2 relative to each other under normal conditions of use. These conditions correspond in particular to those expected during the transport and handling phases.
• the rigid connecting element 12 is adapted to be able to be inserted, at least temporarily, in the mouth with the pads 2, before being removed as will be seen later.
• the system 11 further comprises a guide assembly 13 for the individual positioning of the pads 2, in order to correctly place each pad 2 on the corresponding tooth.
• the guide assembly 13 comprises at least one reference surface, complementary to at least one surface portion of a tooth, other than the surface portion on which the wafer 2 is intended to be fixed.
• the assembly 13 for guiding the individual positioning of the inserts 2 naturally goes into the unique position in which the reference surface is in correspondence with the surface portion complementary to the tooth, ensuring that the corresponding insert 2 is correctly placed.
• the assembly 13 for guiding the individual positioning of the wafers 2 may comprise for this purpose a guide element 14 associated with each wafer 2, which is shaped so as to present at least one reference surface, complementary to at least a portion of the outer surface of the tooth corresponding to the wafer 2, other than the surface portion on which the wafer 2 is intended to be fixed.
• Each guide element 14 comprises a strip of material which preferably connects it rigidly to the corresponding plate 2, and which may or may not participate in guiding. The guide element 14 thus limits the number of degrees of freedom of the insert 2 once positioned on the corresponding tooth. A precise and unequivocal positioning of insert 2 on the corresponding tooth is thus obtained.
• a rigid connecting element 12 between the pads 2 as comprising a strip of material rigidly connecting the guide elements 14 in pairs.
• a rigid connecting element 12 can comprise two guiding elements 14 of the assembly 13 for guiding the individual positioning of the pads 2 and the strip of material connecting them.
• the assembly 13 for guiding the individual positioning of the pads 2 participates in making the rigid connection between the pads 2.
• the strip of material connecting the pads 2 is provided so as to be able to be inserted at least temporarily in the mouth. with the pads 2 and the guide elements 14.
• the rigid connecting element 12 between the pads 2 is intended to be removed once the pads 2 are fixed on the teeth.
• the rigid connection element 12 between the plates 2 is formed by bridges 15 of material between the guide elements 14.
• the bridges 15 have a shape which deviates from the surface of the teeth in order to allow the insertion of a cutting tool of the clamp or milling type.
• the strip of material of the guide elements 14 which connects them to each wafer 2 can moreover be designed to be easily cut, manually or using a tool, at the junction with the wafer 2.
• the system 11 may further comprise an assembly 16 for guiding the positioning of the element 40 of the articulated connection.
• the assembly 16 for guiding the positioning of the articulated connection element 40 is physically separated from the plates 2, that is to say it is at a distance from and without direct contact with the plates 2. More precisely, the The assembly 16 for guiding the positioning of the articulated connection element 40 comprises guides 17, each guide 17 extending between two adjacent plates 2. Each guide 17 materializes the portion of dental surface between two pads 2 with which the articulated connecting element 40 is intended to come into intimate contact. This is for example the lingual surface of the teeth.
• the guides 17 of the assembly 16 for guiding the positioning of the elements 4 of the articulated connection can be connected to the plates 2 via the elements 12 of rigid connection. More precisely, the guides 17 can be connected to the bridges 15 by arms 18.
• the positioning system 11 thus guarantees the correct positioning of the plates 2 in the mouth, as well as the correct shaping of the element 40 articulated connection in order to ensure intimate contact between the articulated connection element 40 and the portion of dental surface between each wafer 2.
• the articulated retention element 40 can be shaped outside the patient's mouth, more easily and with better precision than shaping directly in the mouth. The positioning system 11 thus makes it possible to quickly install the device 1 in the mouth, by limiting the number of operations on the patient, and therefore by increasing his comfort.
• the installation system 11 is preferably one-piece, that is to say made in a single piece, without assembling physically separate elements.
• the installation system 11, which comprises the pads 2, the rigid connecting elements 12, the assembly 13 for guiding the individual positioning of the pads 2, and the assembly 16 of guiding the positioning of the articulated connecting element 40 are formed by so-called additive techniques, such as additive manufacturing, for example in the same material but not necessarily.
• the placement system 11 can be manufactured by so-called subtractive techniques, such as cutting and milling.
• the strips 14 and the bridges 15 in particular can be oversized in order to provide rigidity and robustness to the system 11 which promotes the maintenance of the relative position of the plates 2 between them and the guide elements 14 of the assembly 13 guide to the individual positioning of the inserts 2.
• the installation system 11 can be designed digitally beforehand, from the digital model of the dental arches.
• the articulated connection portions 4 are fixed between the pads 2, on the places 5 of fixing. [101] According to a first embodiment, it is possible to manufacture the articulated connection portions 4 from a wire by shaping it manually or using pliers, on the installation system 11, at the level of the guides 17, outside the mouth.
• the articulated connection portions 4 can be designed by computer, then manufactured automatically by a robot. They are then placed and fixed between the plates 2 using guides 17, outside the mouth.
• the articulated connection portions 4 can be determined from the digital model of the patient's dental arches.
• each portion 4 of articulated connection is determined from a so-called articular curve, that is to say from the curve obtained by the intersection of an articular plane with the lingual surface of the teeth concerned. on the digital model.
• the articular plane is a non-vertical plane, for example horizontal, but not necessarily.
• the terms "horizontal” and “vertical” should be understood here according to their natural meaning, the teeth extending substantially in a vertical direction from the gum.
• Each portion 4 of optimal articulated connection can then be determined by considering a point of placement at the intersection of the articular curve and an interdental line, located between the two teeth considered, on the lingual surface of the teeth for the portion 4 of the articulated connection in question.
• the articulated connection portion 4 can then be constructed around this placement point, as two curved segments or comprising a succession of straight portions tangent at best to the articular curve, and having the placement point as a common end.
• Each segment thus matches the shape of the lingual surface portion of the tooth against which it is applied.
• the two segments can be at the same vertical level, but not necessarily.
• the joint curve can include two placement points. This is the case when the two adjacent teeth considered have their lingual face offset because of the difference in tooth thickness, such as between an incisor and a canine, for example. In this case, a third intermediate segment is determined, and the articulated connection portion 4 has a bayonet shape. [106] In reality, two adjacent teeth meet at a contact surface. The placement point or points are preferably placed vertically in a so-called connection zone, comprised between the point furthest from the gum and the point closest to the gum in the contact surface. [107] Thus, a guide 17 can be determined as representing at least in part all of the possible articular curves, included in the connection zone, for the element 4 of articulated connection considered.
• the system 11 can be manufactured, so as to ensure that the relative position of the pads 2 is maintained before and after the manufacture and fixing of the elements 4 of articulated connection, and possibly until the final gluing of the device 1 for restraint in a patient.
• Manufacturing can be of the additive type, such as 3D printing or sintering, or of the subtractive type, such as cutting, for example, or of the molding type, such as the lost wax technique after rapid resin prototyping castable, or sintering.
• the positioning system 11 can be made from one and the same material, for example metal. Examples include NiCr (Nickel-Chrome), CoCr (Cobalt-Chrome) alloys or even surgical steel. These materials are easily welded to an element 40 of articulated steel connection. In the case of the sintering technique, titanium can replace these examples of materials.
• the articulated connection element 40 can then be made of Ni-Ti (Nickel-Titanium).
• the rigid connecting elements 12 between the pads 2, the assembly 13 for positioning the pads 2 in the guide and the assembly 16 for positioning the articulated connecting element 40 are intended to be removed once the device 1 permanently stuck in the mouth.
• sites of fragility at the level of the connections with the pads 2 can be provided from the design of the installation system 11, or be machined subsequently, as will be seen later.
• the articulated connection element 40 is manufactured, for example by bending a metal wire, preferably stranded. It is shaped so as to follow the shape of the guide 17, which corresponds to the dental surface on the element 40 of articulated connection is intended to come into intimate contact.
• the fact of having portions 4 of individualized articulated connection, between each plate 2, facilitates the bending and shaping.
• the articulated connection portions 4 facilitate bending to follow sudden changes in curvature, such as for example at the level of the extra thickness formed by the wafer 2 on the dental surface and at the level of the limit between two adjacent teeth.
• Folding can be manual, carried out by a technician, following the guides
• each articulated connection portion 4 is each fixed to a location 5 for fixing a plate 2, straddling two adjacent teeth.
• the fixing of the articulated connection portions 4 on the places 5 of fixing of the plates 2 can be carried out for example by welding, for example by TIG micro-welding, by plasma or laser, or by soldering.
• the rigid connection element 12 ensures, during the fixing of the articulated connection portions 4, the maintenance of the relative position of the pads 2.
• the assembly 16 for guiding the positioning of the element 40 of the articulated connection is removed.
• the pads 2 however remain rigidly connected to each other by the elements 12 of rigid connection.
• the surface condition of the internal face of the plates 2 is prepared for bonding, for example by machining a micro-mesh allowing retention of the bonding material.
• the surface condition of the external face 3 remains smooth, except on the places 5 of fixing.
• sites of fragility can be introduced, for example by milling, on the assembly 13 for guiding the positioning of the plates 2, and more precisely at the level of the connection between the plates 2 and the guide elements 14 of the assembly 13.
• the device 1 is installed in the mouth, the pads 2 are glued to the patient's teeth.
• the guide elements 14 of the assembly 13 for guiding the positioning of the pads 2 are applied against the corresponding teeth, so as to correctly position the pads 2 on each tooth.
• the pads 2 are permanently bonded to the teeth.
• the articulated connection element 40 shaped thanks to the guides 17 of the assembly 16 for guiding the positioning of the articulated connection element 40, then perfectly matches the portion of dental surface between each wafer 2.
• the guide elements 14 of the assembly 13 can then be removed. For example, 15 bridges are first cut using pliers cutting edge, then the guide elements 14 are separated from the plates 2 by a rotational movement, the separation taking place at the level of the previously introduced sites of fragility.
• the rigid connection elements 12 and the assembly 13 for guiding the positioning of the pads 2, and possibly the assembly 16 for guiding the positioning of the element 40 of articulated connection are removed in the workshop, before sending it to the practitioner.
• the restraint device 1 is then sent to the practitioner in a gutter ensuring the maintenance of the relative position of the platelets 2 between them.
• a virtual model comprising the plates 2, placed on a dental arch of the patient can be produced in order to manufacture a model, for example by additive manufacturing.
• the articulated connection elements 40 are welded to the pads 2.
• a gutter is formed, for example by thermoforming, from the model of the device 1 on a dental arch, or from a scanner of the device 1 of contention.
• the restraint device 1 thus described, combined with the implementation of the mouthing system 11, makes it possible to provide effective restraint for optimal orthodontic treatment. Indeed, the device 1 ensures that the relative position of the teeth is maintained over time: the device 1 is made to measure, is perfectly positioned on the patient's teeth and the risks of detachment and/or fracture of the device 1 are greatly diminished.
• the occlusal contacts are taken into account, reducing discomfort and eliminating the risk of fracture of the element 40 of the articulated connection.
• the pads 2 have a thickness that can be reduced to a minimum, depending on the minimum stiffness required, so that again the discomfort is reduced.
• the risk that the teeth of the arch opposite to that on which the device 1 is fixed come into abutment against the pads 2 is also reduced thanks to this small possible thickness, and to the custom design of the pads 2.
• the device 1 can thus be placed both on the teeth of the maxillary arch and on the teeth of the mandibular arch, and both on the lingual face and on the labial face of the teeth.
• an articulated connection portion 4 connects two pads 2 on two adjacent teeth, there may be provided, possibly in combination, a connection portion 4 articulated which connects several pads 2,.
• the welding of the hinged connection element 40 on the pads 2 forms a connection which ensures anatomical continuity. Indeed, it is almost impossible to manually unsolder the articulated connection element 40, the welding involving a continuity in the material between the plates 2 and the elements 4 of articulated connection.
• the good hold of the pads 2 on the lingual surface of the teeth is ensured in particular by the optimal bonding surface of the outer face of the pads 2 on the teeth, by their thin thickness which reduces the lever arm on their outer surface 3 , and by their tailor-made positioning.
• the retainer 1 also facilitates good dental hygiene. Indeed, the articulated connection element 40, and in particular the articulated connection portions 4 being shaped as closely as possible to the shape of the lingual face of the teeth, the spaces between the articulated connection elements and the teeth, where food could accommodate, are deleted. In addition, the outer face 3 of the platelets 2 being smooth, food cannot lodge there either. Dental plaque problems are then also reduced for these same reasons.

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• Health & Medical Sciences (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Dentistry (AREA)
• Epidemiology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)

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• 2021
  • 2021-03-23 FR FR2102866A patent/FR3121035B1/fr active Active
• 2022
  • 2022-03-21 WO PCT/EP2022/057287 patent/WO2022200246A1/fr active Application Filing
  • 2022-03-21 EP EP22716918.2A patent/EP4312870A1/de active Pending

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