i was searching for safe, natural, or non-toxic, teethers for a couple of times and finally i found what i really wanted.
round wood rings + crochet = safe, natural and non - toxic teether :)
i bought round natural, unfinished wood rings and varnished them with olive oil. later, i crochet on it. my daughter loved it!! below i added some crochet teethers image, you can make teethers just like them. they are so easy to make.