diff --git a/splib/mechanics/mass.py b/splib/mechanics/mass.py
index a3ee1fe2..c003c3e6 100644
--- a/splib/mechanics/mass.py
+++ b/splib/mechanics/mass.py
@@ -6,18 +6,18 @@
 # TODO : use the massDensity ONLY and deduce totalMass if necessary from it + volume
 
 @ReusableMethod
-def addMass(node, elem:ElementType, totalMass=DEFAULT_VALUE, massDensity=DEFAULT_VALUE, lumping=DEFAULT_VALUE, **kwargs):
+def addMass(node, elem:ElementType, totalMass=DEFAULT_VALUE, massDensity=DEFAULT_VALUE, lumping=DEFAULT_VALUE, topology=DEFAULT_VALUE, **kwargs):
     if (not isDefault(totalMass)) and (not isDefault(massDensity)) :
         print("[warning] You defined the totalMass and the massDensity in the same time, only taking massDensity into account")
         del kwargs["massDensity"]
 
-    # if(elem !=ElementType.POINTS and elem !=ElementType.EDGES):
-    #     node.addObject("MeshMatrixMass",name="mass", totalMass=totalMass, massDensity=massDensity, lumping=lumping, **kwargs)
-    # else:
-    #     if (not isDefault(massDensity)) :
-    #         print("[warning] mass density can only be used on a surface or volumetric topology. Please use totalMass instead")
-    #     if (not isDefault(lumping)) :
-    #         print("[warning] lumping can only be set for surface or volumetric topology")
+    if(elem !=ElementType.POINTS and elem !=ElementType.EDGES):
+        node.addObject("MeshMatrixMass",name="mass", totalMass=totalMass, massDensity=massDensity, lumping=lumping, topology=topology,  **kwargs)
+    else:
+        if (not isDefault(massDensity)) :
+            print("[warning] mass density can only be used on a surface or volumetric topology. Please use totalMass instead")
+        if (not isDefault(lumping)) :
+            print("[warning] lumping can only be set for surface or volumetric topology")
 
-    node.addObject("UniformMass",name="mass", totalMass=totalMass, **kwargs)
+        node.addObject("UniformMass",name="mass", totalMass=totalMass, topology=topology,**kwargs)
 
diff --git a/stlib/materials/deformable.py b/stlib/materials/deformable.py
index 69a9558b..a24763df 100644
--- a/stlib/materials/deformable.py
+++ b/stlib/materials/deformable.py
@@ -14,7 +14,12 @@ class DeformableBehaviorParameters(MaterialParameters):
     parameters : list[float] = dataclasses.field(default_factory=lambda: [1000, 0.45])  # young modulus, poisson ratio
 
     def __addDeformableMaterial(node):
-        addMass(node, node.parameters.elementType, massDensity=node.parameters.massDensity, lumping=node.parameters.massLumping)
+
+        massKwargs = {}
+        if node.parameters.elementType != ElementType.EDGES: #If we use the MeshMatrixMass, then the mass will need us to specify the mstate to use
+            massKwargs["geometryState"] = "@States"
+
+        addMass(node, node.parameters.elementType, massDensity=node.parameters.massDensity, lumping=node.parameters.massLumping, topology="@../Geometry/container", mass=massKwargs)
         # TODO : change this with inheritance
         if(node.parameters.constitutiveLawType == ConstitutiveLaw.HYPERELASTIC):
             addHyperelasticity(node, node.parameters.elementType, node.parameters.parameters, topology="@../Geometry/container")