This article was first published in the September 2015 issue of WIRED magazine. Be the first to read WIRED's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online
Making toothpaste is an intricate process, but it can be done at home. "We have different formulas for what we're trying to achieve with each toothpaste," says Justin Brown, technical director of GlaxoSmithKline's Maidenhead site, where they make Aquafresh and Sensodyne toothpastes. Ingredients are altered to cater to sensitive teeth or to enhance whitening. "This is a standard family oral health formula," Brown says.
What you'll need: Purified water (23g); glycerine (10g); sorbitol (10g); titanium dioxide (0.5g); saccharine (0.5g); 1,000ppm sodium fluoride; 15g abrasive silica (15g); thickening silica (10g); polyethylene glycol (2g); powdered gum (sodium carboxy-methyl cellulose or xantham gum (1g); flavouring (spearmint or peppermint, 1.5g); detergent (such as sodium lauryl sulphate, 1.5g). Most of these are available via Amazon, but some (fluoride and silicas) come from chemical companies.
- Blend itBlitz the water, glycerine, sorbitol, titanium dioxide and saccharine in a blender. You can add more saccharine if you want. The sorbitol is a different type of sweetener; it also gives the paste its shine. The titanium dioxide is for whitening. Then add fluoride, but make sure you are wearing gloves, goggles and a face mask -- this is for the teeth, not the eyes.
- Introduce silicaNow add the two types of silica, and mix. The first is an abrasive, derived from sand; this polishes your teeth. The second is for thickening; it binds everything to give it a toothpastey consistency. "We use 13 silicas across our products," says Brown. Specific types are used depending on the brands. "For our Pronamel range we use a less abrasive one."
- Shake it upTo make the gum slurry, in a separate container add the polyethylene glycol to the powdered gum, and shake it up. "If you put the gum powder straight into the mixer with the liquid you'd just create a lump," says Brown, "as it will interact on immediate contact with water." If you first combine it in a slurry, it will mix into the batch far more effectively.
- Add flavouringsAdd the gum slurry around the edge of the blender and mix it in as quickly as you can. Now add your flavourings. At GSK they have pre-blended flavours, but you can use peppermint or spearmint oil. In the US they prefer their toothpastes sweeter, adding flavours like cinnamon, whereas in Europe, plant-based flavours such as fennel are more common.
- Drop in detergentThe detergent goes in last. This is what gets the toothpaste foaming when you use it and it carries the fluoride around the teeth and gum line. "We have a vacuum system at GSK that we use for de-aeration," says Brown. Pumping out the air bubbles makes the toothpaste shinier, but you can just whack this straight on to your toothbrush.
This article was originally published by WIRED UK
