A tissue-engineering scaffold is a temporary porous framework: it must hold its shape long enough for seeded cells to proliferate and lay down their own extracellular matrix, then quietly disappear. This simulator builds a 3D lattice of scaffold struts at a chosen porosity — the fraction left as open pore space — then runs two competing processes on a simulated weekly clock: the polymer struts erode by first-order hydrolytic degradation while new tissue cells colonize the empty pores by logistic growth. The two rates rarely match by accident — the whole point of scaffold design is tuning a material and pore structure so degradation trails just behind tissue ingrowth.
V(t) = V₀ · e^(−k·t) scaffold volume (first-order degradation)
N(t) = K / (1 + A·e^(−r·t)) colonized pores (logistic growth), A=(K/N₀−1)
- Porosity — the fraction of the lattice left open at t=0; higher porosity gives cells more room to grow into but leaves a weaker, less connected strut network.
- Degradation rate (k) — how fast the scaffold material hydrolyzes and struts vanish each simulated week; ceramics sit near zero, collagen erodes fast.
- Cell growth rate (r) — how fast colonizing cells proliferate to fill the available pore volume, following the same logistic curve that describes bacterial or tissue growth into a finite space.
- Material presets — PLA (moderate, controllable degradation), Collagen (fast-degrading, highly bioactive), Ceramic/hydroxyapatite (bioinert, near-permanent) — set realistic starting points for k and r.
Real-world relevance: matching these two curves is the central design problem in regenerative medicine — a scaffold that degrades too fast collapses before tissue can support itself, and one that degrades too slowly blocks full tissue remodeling and can trigger chronic inflammation.