Javascript – Append HTML to container element without innerHTML

I need a way to append HTML to a container element without using innerHTML. The reason why I do not want to use innerHTML is because when it is use like this:

element.innerHTML += htmldata

It works by replacing all of the html first before adding the old html plus the new html. This is not good because it resets dynamic media such as embedded flash videos…

I could do it this way which works:

var e = document.createElement('span');
e.innerHTML = htmldata;
element.appendChild(e);

However the problem with that way is that there is that extra span tag in the document now which I do not want.

How can this be done then? Thanks!