There are bunch of Oral B mods in internet, but nothing was just what I wanted, so I remixed @mschim design, which was a remix from @MakerMaik design. The fit is snugg (if your extruder is well calibrated) and keeps the chargers in their place in everyday use but you can still easily take them out to wash them.
We have separate bathrooms for boys and girls (arrangement which reduces inhouse complaints by 250%), so both bathrooms have their own twin harbour of tootbrushes, with initials of the users. Included file is only the plain holder with no letters. You can easily add your letters in Microsoft 3D Builder which is free with Windows 10 or with Bambu studio. Then either do filament change in correct layer or paint the letter after printing or use your AMS unit. Or you can also leave lettering out and be surprised whose toothbrush you are using this time.

Print Settings

Printer Brand:

Creality

Printer:

Ender 3

Rafts:

No

Supports:

No

Resolution:

0.3

Infill:

10%

Filament:

GST3D PLA White

Notes:

With print speed of 60mm/s and 2 walls, this takes 2h7min to print and uses 29 grams of filament (9.72 meters).
There is a little overhang, but my printer did fine without supports. Your results may vary!

It is shaped so you should be fine without a brim or raft.

Category: Bathroom