diff --git a/core/simplegraph.class.inc.php b/core/simplegraph.class.inc.php
index f817cd73a..905cc4b7e 100644
--- a/core/simplegraph.class.inc.php
+++ b/core/simplegraph.class.inc.php
@@ -1,5 +1,5 @@
 <?php
-// Copyright (C) 2015 Combodo SARL
+// Copyright (C) 2015-2017 Combodo SARL
 //
 //   This file is part of iTop.
 //
@@ -18,7 +18,7 @@
 /**
  * Data structures (i.e. PHP classes) to manage "graphs"
  *
- * @copyright   Copyright (C) 2015 Combodo SARL
+ * @copyright   Copyright (C) 2015-2017 Combodo SARL
  * @license     http://opensource.org/licenses/AGPL-3.0
  * 
  * Example:
@@ -346,14 +346,15 @@ class SimpleGraph
 		}
 		unset($this->aNodes[$oNode->GetId()]);
 	}
-	
+
 	/**
 	 * Removes the given node but preserves the connectivity of the graph
 	 * all "source" nodes are connected to all "sink" nodes
 	 * @param GraphNode $oNode
+	 * @param bool $bAllowLoopingEdge
 	 * @throws SimpleGraphException
 	 */
-	public function FilterNode(GraphNode $oNode)
+	public function FilterNode(GraphNode $oNode, $bAllowLoopingEdge = false)
 	{
 		if (!array_key_exists($oNode->GetId(), $this->aNodes)) throw new SimpleGraphException('Cannot filter the node (id='.$oNode->GetId().') from the graph. The node was not found in the graph.');
 		
@@ -362,13 +363,19 @@ class SimpleGraph
 		foreach($oNode->GetOutgoingEdges() as $oEdge)
 		{
 			$sSinkId =  $oEdge->GetSinkNode()->GetId();
-			$aSinkNodes[$sSinkId] = $oEdge->GetSinkNode();
+			if ($sSinkId != $oNode->GetId())
+			{
+				$aSinkNodes[$sSinkId] = $oEdge->GetSinkNode();
+			}
 			$this->_RemoveEdge($oEdge);
 		}
 		foreach($oNode->GetIncomingEdges() as $oEdge)
 		{
 			$sSourceId =  $oEdge->GetSourceNode()->GetId();
-			$aSourceNodes[$sSourceId] = $oEdge->GetSourceNode();
+			if ($sSourceId != $oNode->GetId())
+			{
+				$aSourceNodes[$sSourceId] = $oEdge->GetSourceNode();
+			}
 			$this->_RemoveEdge($oEdge);
 		}
 		unset($this->aNodes[$oNode->GetId()]);
@@ -377,7 +384,10 @@ class SimpleGraph
 		{
 			foreach($aSinkNodes as $sSinkId => $oSinkNode)
 			{
-				$oEdge = new RelationEdge($this, $oSourceNode, $oSinkNode);
+				if ($bAllowLoopingEdge || ($oSourceNode->GetId() != $oSinkNode->GetId()))
+				{
+					$oEdge = new RelationEdge($this, $oSourceNode, $oSinkNode);
+				}
 			}
 		}
 	}
diff --git a/test/testlist.inc.php b/test/testlist.inc.php
index d0d698ccf..59e09020e 100644
--- a/test/testlist.inc.php
+++ b/test/testlist.inc.php
@@ -5545,3 +5545,53 @@ class TestBug609 extends TestBizModel
 		}
 	}
 }
+
+class TestBug788 extends TestBizModel
+{
+	static public function GetName()
+	{
+		return 'Graph - delete nodes';
+	}
+
+	static public function GetDescription()
+	{
+		return '(N.788) Graph not refreshed when unchecking some classes';
+	}
+
+	protected function DoExecute()
+	{
+		$oGraph = new SimpleGraph();
+		$a = new GraphNode($oGraph, 'A');
+		$b = new GraphNode($oGraph, 'B');
+		$c = new GraphNode($oGraph, 'C');
+		new GraphEdge($oGraph, 'A--B', $a, $b);
+		new GraphEdge($oGraph, 'B--C', $b, $c);
+		new GraphEdge($oGraph, 'C--B', $c, $b);
+
+		echo "<h5>Graphe initial</h5>";
+		echo $oGraph->DumpAsHtmlImage();
+		echo $oGraph->DumpAsHTMLText();
+
+		echo "<h5>Removing C</h5>";
+		$oGraph->FilterNode($c);
+		unset($c);
+		echo $oGraph->DumpAsHtmlImage();
+		echo $oGraph->DumpAsHTMLText();
+
+		if ((count($oGraph->_GetNodes()) != 2) || (count($oGraph->_GetEdges()) != 1))
+		{
+			throw new Exception('The graph should be made of 2 nodes and 1 edge');
+		}
+
+		echo "<h5>Removing B</h5>";
+		$oGraph->FilterNode($b);
+		unset($b);
+		echo $oGraph->DumpAsHtmlImage();
+		echo $oGraph->DumpAsHTMLText();
+
+		if ((count($oGraph->_GetNodes()) != 1) || (count($oGraph->_GetEdges()) != 0))
+		{
+			throw new Exception('The graph should contain only the node A');
+		}
+	}
+}