This may sound archaic but am sure people in other parts of the world still use the end of a fibrous stick . Liqorice sticks have a sweet Plesent taste ( maybe you need tons of it before it rots the teeth?) whether or not it could be dabbed into a chemical free medium . someone else suggested - was it salt / baking powder? Maybe there's a herbal mouth wash for an antibacterial rinse that's gentle on the ph of the mouth. Rolling a clove about the mouth or fennel seeds which has an aniseed flavour freshens up the mouth. In India there is a combination of seed spices they chew after meals some may help digestion on swallowing too. Maybe Just for that fresh oral hygeine feeling now and again if total toothpaste and brushing is out. The stick end is smaller too. There's also an antibacterial chewing gum but that would be full of chemicals. Sterile saline solution in a squeezy contact lense bottle so no friction "washing lips" has .67% sodium chloride NaCl (salt) .002%EDTA whatever that is and 0.00005%PHMB whatever that is. Salt water in the right concentration is pretty natural and has healing qualities. I guess the contact lense solution concentration is safe and ok enough for the body and sensitive area of the eyes. Keeping it natural and within moderation so as to not upset the balance as the lips try and do their own thing is the aim I guess.