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What are the missing letters? . .?.lginate . .?.ilicone . .?.ycal Hint: A dentist can guess them easily.?

The number of the missing letters for each of the three words (I guess) is three. And these words should be easy for a dentist to guess. That's all the hint I know. I have tried searching some words to resolve this from an online medical dictionary, but I failed to find words that match with the spelling. Could you please help. Many thanks.

Public Comments

1. No idea! Tough one!
2. lost me on that one.sorry!
3. i don't know but it's really annoying someone answer!
4. whoa, good luck with that
5. ...lginate Could that be misspelled? I was thinking amalgamate, which is process of filling a cavity. The other two I'm still thinking. I'm not a dentist by the way.
6. alginate sillicone (that shud be silicone)