7. Guided Tissue Regeneration Flashcards
(30 cards)
What is a Grade I Cervical Enamel Projection?
The enamel projection extends from the CEJ of the tooth toward the furcation entrance.
What is a Grade II Cervical Enamel Projection?
- The enamel projection approaches the entrance to the furcation.
- It does NOT enter the furcation
- No horizontal component is present
What is a Grade III Cervical Enamel Projection?
The enamel projection extends horizontally INTO the furcation
- Can lead to bone loss
Where are Enamel Pearls located?
Apical to the CEJ
- Localized masses of enamel
How do enamel pearls form?
- Localized failure of Hertwig’s epithelial root sheet to separate from the dentin
What is the enamel pearl lined with?
REE
With enamel pearls what can be seen close to the normally formed adjacent cementum?
Epithelial Cell Rests (ECR)
What is the “healing” of the tooth’s supporting tissues, including: alveolar bone, PDL, and cementum
Regeneration
What is the healing of a wound by tissue that does not fully restore the architecture or function of the part?
Repair
- Compromised outcome
- This is what occurs after SRP, where the long JE forms but it isnt CT attachment
- Good but not perfect
What is the clinical restoration of bone tissue in a treated periodontal defect, not addressing the presence or absence of periodontal regeneration or a new attachment?
Bone Fill
What is New Attachment?
- Union of a CT or Epithelium with a root surface that has been deprived of its original attachment apparatus
- Getting tissue back that is lost because of disease (i.e. perio ds)
- Not considered a type of repair
What is Reattachment?
- To attach again such as the reunion of epithelial and CT with root surfaces and bone that occurs after an incision or injury
- There is no disease process, attachment was removed because of surgery, and this is putting it back.
- Ex: following flap surgery, the curetted root surface may be repopulated by:
- Epithelial cells
- Gingival CT cells
- Bone cells
- PDL cells
How fast does epithelium migrate?
0.5-1mm / day
How fast does the PDL migrate?
5x slower than epithelium
0.1 mm/day
How fast does the bone heal/migrate?
100x slower than epithelium
0.05 mm/day
What is the goal of Guided Tissue Regeneration?
- Placement of the physical barrier, which prevents the epithelium and gingival CT from contacting the root surface during healing.
- At the same time the membrane allows cells from the PDL to repopulate the previously periodontitis involved root surface
What osseous defect is considered well contained?
3 wall infrabony defect
What walls are always present in an Interproximal osseous crater?
Buccal and Lingual walls
- There is a dip in the interproximal contour between the plates
What kind of osseous defect is an interproximal crater?
2 wall defect
- Not all 2 wall defects are interproximal craters
What is the treatment for a one-wall angular defect?
Osseous Resective Surgery
If shallow, not for a deep defect
What is the treatment for a two-wall defect?
Either method (resective or regenerative)
- Regenerative if it is containable
What is the treatment for a three-wall defect?
Regeneration
Especially narrow defects
What are the indications for Guided Tissue Regeneration (GTR)?
Done around teeth
- Deep vertical bone defects (2 and 3 walls, circumferential)
- Furcation defects
- Root coverage/gingival recession or dehiscence
What are the indications of Guided Bone Regeneration (GBR)?
Done in an edentulous area for implant purposes
- Bone ridge defects - ridge augmentation
- Extraction sockets - site preservation, immediatly after ext
- Defects associated with dental implants
- Immediate implant placement in a fresh ext site
- Repair of bone dehiscence or fenestration
- Repair of crestal bone loss about implants, peri-implantitis
