Guided Tissue regeneration

• define guided periodontal tissue regeneration:

  formulation of new connective tissue attachment to the root surface, by guiding cells from perio ligament/adjacent alveolar bone
• how do perio defects heal post-operatively?

  by forming LJE
• how to keep LJE stable?

  high standard of OH from pt and regular maintenance program
• what is repair?

  restoration of new tissue that does not replicate the structure and function of lost tissue
• what is regeneration?

  biological process where the function of lost tissue is completely restored
• connective tissue reattachment?

  reunion of connective tissue with root surface on viable periodontal ligament (no underlying perio disease)
• connective tissue NEW ATTACHMENTS?

  reunion of connective tissue with root surface that has been deprived of its periodontal ligament
• indications for GPTR?

  • most class II furcation
  • early class III furcation
  • 2 or 3 walled bony defects
  • circumferential moat defects
• contraindication of GPTR?

  • one walled bony defects
  • horizontal bone loss
  • lack of soft tissue to cover space coronally
  • medical history
  • poor OH
  • pt attitudes
  • economics
  • multiple infrabony defects
  • class III furcation defects
• objective/goals?

  • disease arrest
  • regain health, function, aesthetics
  • regeneration where feasible
  • maintain health
• criteria for success:

  • no bop
  • non-destructive microbiota
  • improved attachment
  • ease of maintenance
• how to place a subgingival barrier?

  • JE cells migrate apically to cover root surface
  • exclusion of cells of gingival connective tissue
  • to facilitate migration of progenitor cells from perio ligament into blood clot, promoting root surface recolonisation
• complication/problems:

  • failure
  • costly
  • infection/abcess formation
  • exfoliation of graft or membrane
  • OH modification
  • trauma causing membrane exposure
  • pulpitis from furcation cleaning
  • aesthetic compromise
  • hypersensitivity
  • rapid recurrence of defect
  • long term maintenance essential
• non-resorbable membrane:

  • requires second surgical stage after 6 weeks to remove membrane
  • most common - Gortex membrane, Tefgen
• resorbale membranes:

  • vicryl membrane (ethicon), glycolide and lactide co-polymer
• Research date for GTR?

  • new cementum formation
  • increased bone sounding
  • lack of controlled studies for benefit
  • reduction in probing depth but no difference in attachment gain