Hi, my kids are not pg, I think from a previous thread you are wondering about that range/level of giftedness for your dd6mos...so my advice might be off the mark, but I'd say offer her something else, pacifier if she's still into that, or another toy or book. Try to separate whether she's going through normal teething needs or bored. Some kids are really bothered by teeth coming in, some much less so. 6 months is prime teeth time, iirc.
If it's just boredom, giving something else/distraction works pretty well, but still there will be times when a child is only interested in the one things you've given them and they'll just have a fit when it's taken away.
Oddly, sometimes reasoning with a gt child will work even at very young ages- rather than attempt disciplining them, just explain in a calm voice that the crayon will give you a tummy ache and make a mess if you chew it, so you have to stop now, or I will take it away. You might be surprised with results. Sometimes they will still have a fit. And, even if it does work, in public you will probably feel like a crazy person, but if it works, it works.
Sigh.
Keeping a gt child from being bored and literally climbing the walls, even one on the more regular (mg) end of things, is just hard/constant work.
Very best of luck!