GUIDED TISSUE REGENERATION

One of the main goals of periodontal therapy is the predictable regeneration of the periodontium by allowing repopulation of periodontal ligament cells into the wound area after surgery and preventing the colonisation of the exposed root surface with epithelial, gingival, and bone cells. In order to achieve this, emphasis has been placed on the use of barrier materials in the form of semipermeable membranes which are interposed between the mucoperiosteal flap and the bone and tooth surfaces during surgery. This technique is known as 'guided tissue regeneration' (GTR) and this article looks at the theory and practice of GTR, as well as reviewing the use of non-resorbable membrane materials such as expanded polytetrafluor-ethylene and ethyl cellulose, and resorbable materials such as collagen and polylactic acid.