Microstomia Splint + Adjustments

Microstomia can impede eating, speech, dental cares, and surgical procedures (intubation) and are a common issue after sustaining a face burn injury.

The orthosis was originally designed by one occupational therapist and one physical therapist from Hennepin Healthcare, Minneapolis USA and some “add-ons” and modifications were added by one occupational therapist from Villa Medica Rehabilitation Hospital in Montreal Canada (she used two already existing mouth models and combined them to the original design, see referenced original files).

****This orthosis should be used following the instructions / adjustments of a licensed medical professional (OT, PT, SLP, MD, etc).**** We recommend using the Mouth impairment and disability assessment questionnaire (MIDA) to evaluate patient's functional outcomes and mouth measures before and after the use of this 3D printed orthosis : https://www.sciencedirect.com/science/article/pii/S0305417917305922

The total cost of this orthosi ranges from 2-3USD$ and the build time ranges from 4hrs-7hrs. The time and cost depend on the different parts of this orthosis that will be printed and the chosen printing parameters (type of printer, Type of plastic filament, print speed, % infill, etc).

If no modification to these designs are needed, individuals can input the files to a Slicer program. If modifications are needed, the files can be imported into a CAD software to then be exported and re-imported into a Slicer program before printing.

PLA with minimally 30% infill is recommended for the base parts (ALL files except the orignial "Microstomia Splint 4 hrs" file need supports), however, higher infill will improve the "pin" strength, which tend to break at lower infill%.

**We recommend that all modified mouth pieces be printed using flexible TPU (to increase comfort) (See images of mouth pieces printed with grey filament)**. A minimum of 60% infill should be used. Increasing the % infill will reduce the flexibility of the mouth pieces. We provide 7 sizes of mouth pieces. We also provided a blender file where you can create new mouth sizes. However, the hole size must stay the same to work with the PLA base.

**UPDATES**:
*2023-10-26: The mouth size 1 file was updated for better fit, we created a size 7 for a patients with a very large mouth. 
*2023-12-01: A size #2, #3, #4 and #5 with the lip thickness of a #6 were added for individuals with thicker lips
*2024-02-08*: A size #4.5 and #5.5 were created
*2024-06-26*: We recommend to wash the mouth pieces between wearing periods using a 1:1 vinegar:water solution.
*2025-05-12: We recommend using biocompatible TPU for the mouthpieces. 
*2025-06-11: A file for each of the PLA mouth base pieces were added to allow users to print up to 5 mouth bases per print my maximizing the build-plate                                                                                                 *2025-08-26: A size #7.5 was added

Once the design is printed, the various parts can be sanded, filed and/or heated to increase comfort. Then, the pieces can be combined and glued into place if needed to have the full orthosis. A string or elastic can be added to the orthosis and pinned to a shirt to prevent it from falling to the ground if it falls out of the mouth. This can also prevent accidental swallow.

Contraindications:
-Monitor for signs of pressure that may lead to skin or gum breakdown (The patient’s oral cavity should be checked daily for signs of tissue breakdown or irritation)
-Discontinue this device if it causes tissue irritation, if it interferes with breathing, or if it is not tolerated by the patient.
-The orthosis is made for a specific patient and should not be shared with others.
-Do not use this device on a patient who is orally intubated or who has an orogastric feeding tube.
-Do not use this device while the patient sleeps.
-Do not use this device with young children or with adults who have cognitive safety deficits (choking hazard) unless the different parts are clued into place and users must be supervised while using the orthosis if this is the case.
-Take precaution using this device if the patient has loose teeth, oral infections, or poor dental health.
-Please wash the mouth pieces between wearing periods using a 1:1 vinegar:water solution.