Orthodontic Corner: Cell Homing, Regeneration of Pulp Like Tissue in Root Canal Treated Human Teeth.

Thursday 10 June 2010

Cell Homing, Regeneration of Pulp Like Tissue in Root Canal Treated Human Teeth.

Lately there has been articles and posts around dental blogs, with pictures of this tooth shape scaffold.

From the University of Columbia Dr. Jeremy Mao et all have published an article in May 2010. On this article root canal treated, real size human teeth are transplanted to the dorsum of mouses and were injected on the internal dentin surface of the root canal treated teeth with human bone marrow stem cells, and growth factors (VEGF and/or bFGF) and nerve growth factors (NGF)

This technique is mentioned as cell homing and within 3 weeks, there was a pulp like tissue, generated, with vascularization signs. This could indeed be a breakthrough for the future, and an alternative to implants or transplantations, and auto-transplantations. But for now it is shown, that in vivo, at least on the dorsum of a mouse, pulp like tissue can be regenerated and interact with the dentine on the root canal treated tooth.

Also on a previous article, the same team showed that implanting at athymic rats, on a thin layer of poly-ether, of human bone marrow cells with osteogenic differentiation potential, gave, in vivo generation of a condyle shape bone tissue, again with the cell homing approach. Here is the link of the second article.

On this post at the Columbia University website, the author announces the results of another article on the Journal of Dental Research, latest issue, from Dr. Mao's team. This is the link of the article that does not provide an abstract but however if you have the subscription you can access the whole article.

1) A hybrid scaffold of a rat mandibular central incisor was constructed, by poly-caprolactone, and hydroxyapatite with microstrands connecting and acting as conduits for cell homing and angiogenesis.

2) Following, the central incisor of the rat was extracted.

3) The scaffold was transplanted on the extraction socket, and the result was integration of the scaffold with surrounding tissue as well as tissue in growth at the scaffold. There were some limitations and mainly the root and pieces of sub-occlusal crown were regenerated.

The latest could give the opportunity of cell homing, regeneration at the root level that could act as an anchor to prosthetic reconstructions of the occlusal - visible part of the tooth. Even with this limitation the results are of clinical value.

Future looks promising on the field of tissue engineering, and it seems like, that previous attempts were concentrating or very complex procedures, while a simple scaffold or just homing of human bone marrow stem cells, on regular human tissue as dentin, could do the trick. All remains to be seen.