Periodontal Regeneration

regeneration

-optimal goal of periodontal therapy

-procedures are only an option in certain periodontal defects

procedures that have been used to achieve periodontal regeneration

-root surface modification (not as a monotherapy)

-bone replacement grafting

-guided tissue regeneration (GTR)

-biologic mediators (Emdogain, growth factors)

-combination therapies

-LANAP (laser)

root surface modifications

-hypothesized to work by removing the smear layer and bacterial endotoxins from the root surface and demineralizing hard tissue to expose collagen fibrils facilitating new attachment

-EDTA, citric acid, doxycycline, tetracycline

bone replacement grafts

properties of bone replacement grafts

_____ defines the nature of attachment or healing that occurs

-cell type that repopulates an exposed root surface

guided tissue regeneration

-mesenchymal cells from the PDL and perivascular cells from the alveolar bone that are important in the formation of new bone, PDL, and cementum

healing following implantation of periodontitis-affected roots into gingival connective tissue results

guided tissue regeneration- apical migration

-apical migration of epithelial cells occurs faster than root surface colonization by cells with regenerative potential

-guided tissue regeneration procedure uses an occlusive membrane barrier to exclude epithelial down-growth and promote periodontal regeneration

principles of GTR

-epithelial exclusion

-space creation (and maintenance)

-stabilization of clot

-complete coverage of sites

important membrane properties

-biocompatible

-effective barrier for undesirable cell types

-capable of maintaining the space in the defect

-permits tissue integration (to prevent rapid epithelial down-growth on the outer surface of the material and to provide stability to the overlying flap)

-easy to manage

types of membranes

combination therapy

-bone graft + membrane

GTR in furcation defects

GBR

enamel matrix derivative

-harvest from porcine teeth

-contains a mixture of various proteins (mostly amelogenins)

-postulated to “mimic” natural tooth development and therefore promote regeneration

-clean out defect, put in EDTA, add emdogain to defect, don’t probe area for a long time

growth factors

LANAP/LAR

emerging technologies

-stem cell therapies

-gene therapies: uses genetically modified cells to deliver specific doses of a bioactive protein for a sustained period

-3D printing

factors affecting the success of periodontal regenerative therapy

intrabony periodontal defect flowchart

healing after bone grafting

-histologic studies in both humans and animals have often shown that healing after grafting procedures often results with a long JE rather than a new CT attachment

healing after GTR- _____ is necessary to confirm the formation of new bone, PDL, and cementum

-histology

when should the results of surgical procedures be evaluated?

-wait 8-12 weeks after procedures such as open flap debridement, modified widman flap, osseous surgery

-wait at least 6 months to evaluate the final result of grafting/GTR procedures