In this poster we present mid-IR imaging and spectroscopy of several proplyds in Orion. 
The high spatial resolution and sensitivity of  VISIR/VLT has allowed to resolve dusty 
structures around several proplyds. The spectra of the objects do not show the silicate 
emission feature at 9.8 microns but a strong PAH emission at 11.3 microns. This result is in 
agreement with the suggested anticorrelation (Shuping et al. 2006) between  the strength of 
the silicate emission and the distance to Tetha Ori~1 C, the ionizing source in the 
Trapezium.