Retainer Travel Case — Screw-Top with Soak Base

This is a storage and soaking case for a clear retainer or aligner. It is not a sterilizer and it is not a medical device. Keep it clean, replace it periodically, and follow your orthodontist's guidance on retainer care.

We've all been handed one: the thin little clamshell case that comes with your aligners. It cracks, it pops open in a bag, and the hinge gives out right about the time you actually need it. This is the replacement: a solid screw-top case that closes with a satisfying turn and won't surprise you at the bottom of your carry-on. Good for the nightstand, great for travel.

In a rush?

Print the lid and one base design of your choice. PLA or PETG, 0.4 mm nozzle, 0.2 mm layers, 15% infill, no supports, no brim. About 52 g for both parts together. Screw it together, work it open and closed a few times to break in the threads, and you're done. Enjoy!

A few nice touches

The base is deep enough to soak a retainer in a mild cleaning solution (a little liquid or foam soap works well; leave the lid off while you soak). The lid has small vent holes so the inside doesn't get clammy and stale while it's closed up.

Around the outside is a raised tooth motif, repeated all the way around for grip and a bit of fun. Each tooth is split across the seam between lid and base. When the case is fully closed, the teeth line up into a clean row. Don't be alarmed if the teeth look off at first; the threads need a few open/close cycles to settle, after which everything snaps into alignment.

Pick your base

The lid is plain. The base comes in two flavors, so print whichever suits you (or both):

• (a) Smiley face — simple and cheerful

• (b) "KEEP CLEAN & SMILE ON" — a little motto to live by

Roughly 85 mm across and 30 mm tall, so it tucks into a bag, a drawer, or a Dopp kit without fuss.

Print Settings

• Nozzle: 0.4 mm

• Layer height: 0.2 mm

• Infill: 15%

• Supports: No

• Brims: No

• Filament: PLA or PETG

• Filament used: about 52 g total for both parts

A word on cleaning

Mild soap and water is the safe bet for cleaning. Use a little liquid or foam soap in the base, then rinse and air-dry between uses. Skip the fizzy retainer-cleaner tablets and powders in this case: aside from how the effervescent agents may interact with PLA or PETG over time, the base is small enough that an active tablet can foam up and overflow. Use a separate cup or bowl if you prefer that method.

Remember, a printed case isn't sterile, and PLA in particular can harbor bacteria the longer it's in service. Keep the case clean, and retire it and print a fresh one every so often. They're cheap to make—that's part of the point.

Feedback

I hope this one saves you the frustration of one more broken clamshell. I'd love to see your makes and hear how it works out. If you'd like a different base design, a different motto, or a tweak to the sizing, let me know. Happy to give reasonable requests a shot.

Licensing

My own original work, licensed Creative Commons — Attribution — Noncommercial — Share Alike. Please don't repost the model or sell makes; print them, gift them, and help a few people smile on.