Modeling of light propagation in dentin

The knowledge of the scattering phase function, which describes the angular intensity distribution of the scattered light, is important for modeling the light propagation in turbid media. This is especially true for structured media, where light propagation is anisotropic, leading to direction-dependent reflected or transmitted intensity profiles. We investigated scattering by combining analytical solutions and finite difference time domain (FDTD) simulations of the Maxwell equations with two-axes goniometric experiments. Using polystyrene spheres and cylindrical phantoms the methods were successfully validated. The phase functions of dentin slabs were measured and it is shown that the scattering of dentin tubuli resembles cylinder scattering.

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