diff --git a/mayan/apps/metadata/classes.py b/mayan/apps/metadata/classes.py
index 34ab5c1ac3..49bf81d41c 100644
--- a/mayan/apps/metadata/classes.py
+++ b/mayan/apps/metadata/classes.py
@@ -4,38 +4,6 @@ from .models import DocumentTypeMetadataType, MetadataType
 from .tasks import task_add_required_metadata_type, task_remove_metadata_type
 
 
-class DocumentTypeMetadataTypeHelper(object):
-    @staticmethod
-    @property
-    def constructor(source_object):
-        return DocumentTypeMetadataTypeHelper(source_object)
-
-    def __init__(self, instance):
-        self.instance = instance
-
-    def filter(self, **kwargs):
-        return self.get_query_set(**kwargs)
-
-    def all(self):
-        return self.get_query_set()
-
-    def get_query_set(self, **kwargs):
-        try:
-            return MetadataType.objects.filter(pk__in=self.instance.metadata.filter(**kwargs).values_list('metadata_type', flat=True))
-        except MetadataType.DoesNotExist:
-            return MetadataType.objects.none()
-
-    def add(self, metadata_type, required=False):
-        if metadata_type not in self.instance.metadata_type.all():
-            DocumentTypeMetadataType.objects.create(document_type=self.instance, metadata_type=metadata_type, required=required)
-            if required:
-                task_add_required_metadata_type.apply_async(kwargs={'metadata_type_id': metadata_type.pk, 'document_type_id': self.instance.pk}, queue='metadata')
-
-    def remove(self, metadata_type):
-        DocumentTypeMetadataType.objects.get(document_type=self.instance, metadata_type=metadata_type).delete()
-        task_remove_metadata_type.apply_async(kwargs={'metadata_type_id': metadata_type.pk, 'document_type_id': self.instance.pk}, queue='metadata')
-
-
 class DocumentMetadataHelper(object):
     @staticmethod
     @property
diff --git a/mayan/apps/metadata/views.py b/mayan/apps/metadata/views.py
index f98c994afb..3617803b28 100644
--- a/mayan/apps/metadata/views.py
+++ b/mayan/apps/metadata/views.py
@@ -295,7 +295,7 @@ def metadata_view(request, document_id):
         'object_list': document.metadata.all(),
         'extra_columns': [
             {'name': _(u'Value'), 'attribute': 'value'},
-            {'name': _(u'Required'), 'attribute': encapsulate(lambda x: x.metadata_type in document.document_type.metadata_type.filter(required=True))}
+            {'name': _(u'Required'), 'attribute': encapsulate(lambda x: x.metadata_type in document.document_type.metadata.filter(required=True))}
         ],
         'hide_link': True,
         'object': document,
@@ -404,10 +404,10 @@ def setup_document_type_metadata(request, document_type_id):
 
     return assign_remove(
         request,
-        left_list=lambda: generate_choices_w_labels(set(MetadataType.objects.all()) - set(document_type.metadata_type.filter(required=False)) - set(document_type.metadata_type.filter(required=True)), display_object_type=False),
-        right_list=lambda: generate_choices_w_labels(document_type.metadata_type.filter(required=False), display_object_type=False),
-        add_method=lambda x: document_type.metadata_type.add(x, required=False),
-        remove_method=lambda x: document_type.metadata_type.remove(x),
+        left_list=lambda: generate_choices_w_labels(set(MetadataType.objects.all()) - set(MetadataType.objects.filter(id__in=document_type.metadata.values_list('metadata_type', flat=True))), display_object_type=False),
+        right_list=lambda: generate_choices_w_labels(document_type.metadata.filter(required=False), display_object_type=False),
+        add_method=lambda x: document_type.metadata.create(metadata_type=x, required=False),
+        remove_method=lambda x: x.delete(),
         extra_context={
             'document_type': document_type,
             'navigation_object_name': 'document_type',
@@ -424,10 +424,10 @@ def setup_document_type_metadata_required(request, document_type_id):
 
     return assign_remove(
         request,
-        left_list=lambda: generate_choices_w_labels(set(MetadataType.objects.all()) - set(document_type.metadata_type.filter(required=False)) - set(document_type.metadata_type.filter(required=True)), display_object_type=False),
-        right_list=lambda: generate_choices_w_labels(document_type.metadata_type.filter(required=True), display_object_type=False),
-        add_method=lambda x: document_type.metadata_type.add(x, required=True),
-        remove_method=lambda x: document_type.metadata_type.remove(x),
+        left_list=lambda: generate_choices_w_labels(set(MetadataType.objects.all()) - set(MetadataType.objects.filter(id__in=document_type.metadata.values_list('metadata_type', flat=True))), display_object_type=False),
+        right_list=lambda: generate_choices_w_labels(document_type.metadata.filter(required=True), display_object_type=False),
+        add_method=lambda x: document_type.metadata.create(metadata_type=x, required=True),
+        remove_method=lambda x: x.delete(),
         extra_context={
             'document_type': document_type,
             'navigation_object_name': 'document_type',