diff --git a/oox/source/drawingml/chart/chartconverter.cxx b/oox/source/drawingml/chart/chartconverter.cxx
index b39ca7083f4a..acbe9bbaa47f 100644
--- a/oox/source/drawingml/chart/chartconverter.cxx
+++ b/oox/source/drawingml/chart/chartconverter.cxx
@@ -54,7 +54,7 @@ static OUString lclGenerateApiString( const OUString& rString )
     sal_Int32 nQuotePos = aRetString.getLength();
     while( (nQuotePos = aRetString.lastIndexOf( '"', nQuotePos )) >= 0 )
         aRetString = aRetString.replaceAt( nQuotePos, 1, "\"\"" );
-    return OUStringBuffer().append( '"' ).append( aRetString ).append( '"' ).makeStringAndClear();
+    return "\"" + aRetString + "\"";
 }
 
 static OUString lclGenerateApiArray( const Matrix< Any >& rMatrix )
diff --git a/sc/source/filter/oox/formulabase.cxx b/sc/source/filter/oox/formulabase.cxx
index e1237b7c6100..38f0ef234d3d 100644
--- a/sc/source/filter/oox/formulabase.cxx
+++ b/sc/source/filter/oox/formulabase.cxx
@@ -1624,7 +1624,7 @@ OUString FormulaProcessorBase::generateApiString( const OUString& rString )
     sal_Int32 nQuotePos = aRetString.getLength();
     while( (nQuotePos = aRetString.lastIndexOf( '"', nQuotePos )) >= 0 )
         aRetString = aRetString.replaceAt( nQuotePos, 1, OUString( "\"\"" ) );
-    return OUStringBuffer().append( '"' ).append( aRetString ).append( '"' ).makeStringAndClear();
+    return "\"" + aRetString + "\"";
 }
 
 OUString FormulaProcessorBase::generateApiArray( const Matrix< Any >& rMatrix )