Ok, thank you. To be complete in my information, i only used the OnContentPrepare trigger.
In content article there are also triggers for OnConentAfterTitle, OnContentBeforeDisplay and OnContentAfterDisplay.
view.html.php
//
// Process the content plugins.
//
JPluginHelper::importPlugin('content');
$results = $dispatcher->trigger('onContentPrepare', array ('com_content.article', &$item, &$this->params, $offset));
$item->event = new stdClass();
$results = $dispatcher->trigger('onContentAfterTitle', array('com_content.article', &$item, &$this->params, $offset));
$item->event->afterDisplayTitle = trim(implode("\n", $results));
$results = $dispatcher->trigger('onContentBeforeDisplay', array('com_content.article', &$item, &$this->params, $offset));
$item->event->beforeDisplayContent = trim(implode("\n", $results));
$results = $dispatcher->trigger('onContentAfterDisplay', array('com_content.article', &$item, &$this->params, $offset));
$item->event->afterDisplayContent = trim(implode("\n", $results));
tmpl/default.php after title and before text:
<?php if (!$params->get('show_intro')) :
echo $this->item->event->afterDisplayTitle;
endif; ?>
<?php echo $this->item->event->beforeDisplayContent; ?>
tmpl/default.php at the end:
<?php echo $this->item->event->afterDisplayContent; ?>