osteoblasts
Or maybe a bone kitchen or bone assembly line.
" Bone cells called osteoclasts are like a demolition crew, breaking down old bone material while cells called osteoblasts are like a construction crew, building up new bone material as the old stuff is demolished."
"Osteoblasts are like Tetris, they build up the bone while osteoclasts are like Pacman, they re-absorb bone tissue. We suffer from bone loss as we get older due to these being out of balance."

METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.