Unusual Georg Jensen sterling silver flatware

I collect Georg Jensen flatware but have pieces that came my Great Aunt that are odd and I’m trying to figure out what they were used for. I have two spoons that are 6.25" long and two forks that are 6.25" long. They are the Acorn pattern and have sterling silver handles and black plastic stems and bowls.One of the spoons has several dents in the plastic bowl and a dent in the stem that look like teething marks. I also have a similar butter spreader in the Cactus pattern that is 5.875" long that has a sterling silver handle and a black plastic blade. Does anyone know why this flatware has plastic utensil areas? Are they baby flatware? Any information would be helpful as these are unusual and would love some feedback. Thanks.
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