diff --git a/src/meshlabplugins/filter_meshing/quadric_simp.cpp b/src/meshlabplugins/filter_meshing/quadric_simp.cpp
index a3ba4d41a..05020aa38 100644
--- a/src/meshlabplugins/filter_meshing/quadric_simp.cpp
+++ b/src/meshlabplugins/filter_meshing/quadric_simp.cpp
@@ -79,6 +79,7 @@ void QuadricSimplification(CMeshO &m,int  TargetFaceNum, bool Selected, tri::Tri
       if ((*vi).IsS()) (*vi).ClearS();
     }
   }
+  tri::QHelper::TDp()=nullptr;
 }
 
 
@@ -139,5 +140,7 @@ void QuadricTexSimplification(CMeshO &m,int  TargetFaceNum, bool Selected, tri::
 	}
   }
 	
+  tri::QuadricTexHelper<CMeshO>::TDp3()=nullptr;
+  tri::QuadricTexHelper<CMeshO>::TDp()=nullptr;
 
 }