PROCESS FOR MANUFACTURING CUSTOMIZED FACEMASKS FOR THE TREATMENT OF MALOCCLUSION

Abstract

A process for manufacturing customized facemasks, includes: producing respective impressions of patient's forehead and chin, to record an anatomic structure thereof, using impression materials commonly utilized in dentistry for intraoral impressions; producing respective 3D digital images of a patient's forehead and chin through a 3d-scanning of the forehead and chin impressions; 3D printing of customized forehead and chin pads; detecting patient's side profile line from a side picture of patient's face; 3D printing of a midline rod modelled according to said profile line; and assembling the forehead and chin pads and said midline rod into a facemask featuring a facial frame providing retention to elastic bands connectable to an intraoral appliance, in the forehead pad a temperature sensor is inserted while a pressure sensor is embedded into the chin pad.

Claims

1. Process for manufacturing customized facemasks, especially for the treatment of Class III malocclusions, the process comprising: producing respective impressions (1, 2) of a patient's forehead and chin, to record an anatomic structure thereof, using impression materials; producing respective 3D digital images of the patient's forehead and chin through a 3d-scanning of said forehead and chin impressions (1, 2); 3D printing of customized forehead and chin pads (1, 2); detecting the patient's side profile line (3) from a side picture of the patient's face; 3D printing of a midline rod modelled according to said profile line; and assembling said forehead and chin pads and said midline rod into a facemask featuring a facial frame providing retention to elastic bands connectable to an intraoral appliance, wherein, in the forehead pad (1) a temperature sensor is inserted while a pressure sensor is embedded into the chin pad (2).

2. The process for manufacturing customized facemasks according to claim 1, wherein said forehead and chin pads (1, 2) are 3D-printed using a biocompatible, transparent, 3D-printable photopolymer.

3. The process for manufacturing customized facemasks according to claim 1, wherein said forehead and chin pads (1, 2) are 3D-printed using 3D-printable silicones.

4. The process for manufacturing customized facemasks according to claim 1, wherein said forehead and chin pads (1, 2) are 3D-printed using at least one of 3D-printable: Polyamide 10, Polyamide 11, or Polyamide 12.

5. The process for manufacturing customized facemasks according to claim 2, wherein said midline rod (3) is 3D printed using Polyamide 12.

6. The process for manufacturing customized facemasks according to claim 1, wherein the chin pad (2) include comprises a cushioned sliding mechanism, in order to ease opening and closing movements of the mandible.

7. The process for manufacturing customized facemasks according to claim 1, wherein said sensors are linked to an application for tablets, smartphones or computers including a videogame designed to enhance patient compliance with wearing the facemask.

Description

[0024] The process for manufacturing customized facemasks for the treatment of malocclusions of this invention will be disclosed hereinafter with reference to a preferred embodiment thereof, given with exemplificative and no limitative purpose in connection with the annexed drawings wherein:

[0025] FIG. 1A shows a frontal view of a facemask according to the present invention;

[0026] FIG. 1B shows a side view of the facemask of FIG. 1A;

[0027] FIG. 2 shows a forehead impression of a patient, which can be scanned to obtain a 3D digital image, usable through a 3D printer to print a forehead pad;

[0028] FIG. 3 shows a chin impression of a patient, which can be scanned to obtain a 3D digital image, usable through a 3D printer to print a chin pad;

[0029] FIG. 4 shows a side view of a patient, wherein the profile line of the face is detected, and a 3D model view of a midline rod obtained from said detection;

[0030] FIG. 5 shows a perspective view of a facemask according to the invention, and of a tablet linked to the facemask sensors; and

[0031] FIGS. 6A, 6B and 6C illustrate different screenshot of a smartphone application linked to the facemask sensors.

[0032] The process for manufacturing customized facemasks, in particular for the treatment of Class III malocclusions, comprises a step of acquiring 3D images of the patient's forehead and chin, to appropriately model the forehead and chin pads in the facemask. The facemask can then be connected to an intraoral appliance by means of elastic bands.

[0033] In this connection, process for manufacturing customized facemasks 10 comprises the step of assembling said forehead and chin pads 1, 2 into a facemask featuring a facial frame providing a retention to elastic bands meant to be connected to an intraoral appliance.

[0034] In particular the facemask 10 comprises customized forehead and chin pads, mounted onto a customized midline rod. The midline rod provides retention to elastic bands. As mentioned before, the 3D image is acquired by scanning forehead and chin impressions 1 and 2 of the anatomic structures of interest (FIGS. 2, 3), recorded with materials commonly used in dentistry for intraoral impressions.

[0035] Thereafter, onto the digital images of forehead and chin the corresponding pads can be custom-designed using an appropriate software for 3D digital modelling. Finally, the 3D digital models of the pads can be produced by a 3D-printer.

[0036] The customized frontal and mental pads are assembled together with a customized midline rod into the facemask 10.

[0037] In this connection, according to the present process, a patient's side picture is shot to detect the profile line 3 of the patient (FIG. 4), and the midline rod 3 is shaped according to said profile line.

[0038] Therefore, the midline rod is customized in length, curvature, and position of the retentions for elastic bands by modelling it with a software onto a digital photograph of the patient's face.

[0039] The midline rod features a retentions for the elastic bands at the level of the patient's mouth, providing retention to elastic bands that are to be connected to an intraoral appliance. The elastic bands apply a forward traction to the intraoral appliance while transmitting, through the midline rod, a compressive force onto the frontal and mental pads, that act as supports. The sliding of the chin pad along the midline rod allows the patient to open and close the lower jaw while wearing the facemask 10.

[0040] The application of 3D-modelling and 3D-printing technologies prompt a breakthrough in the design of the maxillary protraction facemask and consequently enhance patients' acceptance of the appliance and treatment's outcome.

[0041] Firstly, customization of the chin and forehead pads is expected to result into good fitting, better stability and even pressure distribution over chin and forehead, thus limiting the chance for skin irritation and the risk of gingival recessions.

[0042] In addition to individualized morphology, also appropriateness of the pad material can contribute to the overall comfort of the facemask. A material suitable for the above purpose is a biocompatible, transparent 3D-printed photopolymer named. A good candidate for this polymer is the product MED610, by Stratasys Ltd. The polymer is adequate for prolonged skin contact and has five medical approvals including cytotoxicity, genotoxicity, delayed type hypersensitivity, irritation and United States Pharmacopeia (USP) plastic class VI.

[0043] Additionally, 3D-printable silicones have been developed for the fabrication of facial prostheses and may be adequate also to produce customized facemasks.

[0044] Other 3D-printable biocompatible polymers possibly applicable to the production of the customized facemask components are Polyamide 10, Polyamide 11, and Polyamide 12.

[0045] Moreover, different allergy-free textiles can be tested as liners of the inner surface of the mental and frontal pads, with the aim of preventing irritations even of the most sensitive skin types.

[0046] For fabrication of the facemask midline rod 3, Polyamide is used through a 3D printing process. Polyamide 12 makes the rod lighter and less evident, as compared with the 0.075 stainless steel used in currently marketed facemasks. Also, the sliding mechanism of the chin cup can be cushioned in order to ease opening and closing movements of the mandible.

[0047] In the process of 3D-printing, electronic sensors measuring pressure and temperature can be incorporated respectively into the chin and the forehead pads to monitor patient compliance, as well as to create a database of appliance wear-times useful for research purposes. Sensors will also be wirelessly linked to an application for tablets (FIG. 5) and smartphones 5 (FIGS. 6A to 6C), which will include a videogame designed to enhance patients' compliance with wearing the facemask.

[0048] The longer the child will wear the facemask 10, the further he/she will advance in the game, as illustrated through FIGS. 6A to 6C. The introduction of a gamification strategy into the management of facemask treatment is truly innovative and wanted, as previous studies on the insertion of temperature sensors inside the frontal pad of standardized facemasks have demonstrated that the awareness of being monitored did not result in patients' full adherence to the doctor's recommendations regarding wear time.

[0049] The agonistic drive is expected to represent an additional motivation for the patient, favoring treatment success.

[0050] It is also unprecedented the idea to insert a pressure sensor into the mental pad of the facemask, as so far only temperature sensors have been used for monitoring purposes.

[0051] Through the above described process, it is possible to achieve customized facemasks which, in addition to the above highlighted advantages, show a remarkable difference in weight with respect to the currently known facemasks.

[0052] To the above-described process for manufacturing customized facemasks for the treatment of malocclusion a person skilled in the art, with the purpose of satisfying additional and contingent needs, could introduce several additional modifications and variants, however all comprised within the protective scope of the present invention, as defined by the enclosed claims.

BIBLIOGRAPHY

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