Techniques for enhancing and directing cell growth to repopulate specific parts of the PERIODONTIUM that have been damaged by PERIODONTAL DISEASES; TOOTH DISEASES; or TRAUMA, or to correct TOOTH ABNORMALITIES. Repopulation and repair is achieved by guiding the progenitor cells to reproduce in the desired location by blocking contact with surrounding tissue by use of membranes composed of synthetic or natural material that may include growth inducing factors as well.