Gotlieb EL, Murray PE, Namerow KN, Kuttler S, Garcia-Godoy F. An Ultrastructural Investigation of Tissue-Engineered Pulp Constructs Implanted Within Endodontically Treated Teeth. The Journal of the American Dental Association. 2008 Apr;139(4):457–65. doi: 10.14219/jada.archive.2008.0189.