With the CSS3 border-image property, you'll set a picture to be used because the border around an element.
#borderimg {
border: 10px solid transparent;
padding: 15px;
border-image: url(border.png>
30 stretch;
}
<p>Here, the middle sections of the image are stretched to create the border:</p>
<p id="borderimg">border-image: url(border.png>
30 stretch;</p>