ngDialog.open event is creating new controllers?

Question

I have a link where user clicks to see details of some information. This click fires a ng-dialog open event, like:

 ngDialog.open({
  template: 'partials/acaoDetalhe.html',
  className: 'ngdialog-theme-default ngDialogSize',
  controller: MetaController,
  scope: $scope

});

and a listener so that when the dialog gets opened, the listener retrieves other informations of the MetaController.

$scope.$on('ngDialog.opened', function (e, $dialog) {
  console.log('ngDialog opened: ' + $dialog.attr('id'));
  $scope.$broadcast('getMetaCompletaEvent', $scope.meta.id);

}); 

It works fine the first time user clicks on the link. The functions of the controller are called and information is retrieved from backend. But after the user clicks outside the dialog window and click on the link again, the methods of the controller are called twice. If the user "closes" the dialog again and click again on the link, methods of the controller are called three times. It seems like the dialog remains hidden and every time user clicks on the link, a new dialog is opened and another controller is created. Why does it happen ? I need the other dialogs to really close after user clicks outside them.