4. What is guided tissue regeneration?
The method for prevention of epithelial migration
along the cemental wall of the pocket and
maintaining space for clot stabilization is a
technique called guided tissue regeneration
( GTR ).
GTR consists of placing barriers of different
types ( membranes ) to cover the bone &
periodontal ligament, thus temporarily separating
them from gingival epithelium and connective
tissue.
5.
6. This Method is derieved from the Classic
Studies Of Nyman, Lindhe, Karring, & Gottlow
and is based on the assumption that only the
periodontal ligament cells have the potential for
regeneration of attachment apparatus of the
tooth.
Excluding the epithelium and the gingival
connective tissue from the root surface during
the post surgical healing phase not only
prevents epithelial migration into the wound but
also favors repopulation of the area by the cells
from the periodontal ligament and the bone.
7. Type specific area repopulation theory
Melcher in 1976 gave this theory.
It stated that the curetted root surface may be
repopulated by
1) epithelial cells.
2) gingival connective tissue cells.
3) bone cells.
4) periodontal ligament cells.
8. Indications
Class 2 furcation.
Infra bony defect.
Recession defect.
To restore PDL attachment in narrow 2 or 3 walled
infra bony defect.
Alveolar ridge augmentation.
Repair of apicocetomy defect.
9. Contraindications
In cases where flap vascularity will be
compromised.
Very severe defect minimal remaining
periodontium.
Horizontal defects.
In cases of flap perforation.
10. Ideal properties
It should be bio compatible & or allow tissue
regeneration.
It should be non toxic and non cariogenic.
It should be chemically inert.
It should be able of being sterilized.
It should be easy to handle during surgery.
11. It should be sufficiently rigid so as to maintain a
space between it and the root surface.
It should be supplied in different design to suit
the specific clinic situation.
It should be easily stored & should have a long
shelf life.
It should be easily retrievable in case of
complication.
It should be cost effective.
16. Non bioresorbable membrane
It Is biocompatible porous material possessing two
unique microstructure.
One is the open microstructure of its collar which is
designed to retard or inhibit the apical proliferation
of epithelium through contact inhibition.
The other is occlusive membrane which acts as a
barrier to the gingival connective tissue & underlying
root surface.
17. Different shapes and sizes of expanded PTFEa
membranes are available.
The use of polytetraflouroethylene membranes has
been tested in controlled clinical studies in
mandibular molar furcations and has shown
statistically significant decreases in pocket depths
and in improvement in attachment levels after 6
months but bone level measurements have been
inconclusive.
18. Non bioresorbable membranes are
available in four configuration
Wrap around.
Interproximal.
Single tooth wide.
Single tooth narrow.
19. Bioresorbable membrane
Composed of ploylactic acid bonded with a citric
acid ester.
It is designed to provide initial barrier function
during the early stages of healing ( minimum of
6 week ) & during later stages, the barrier is
slowly resorbed and replaced by the periodontal
tissue underlying root surface.
20.
21. Procedure for placement of the
membrane
Raise the mucoperiosteal flap with vertical
incisions,extending a minimum of two teeth
anteriorly and one tooth distally to the tooth being
treated.
Debride the osseous defect & thoroughly plane the
roots.
Trim the membrane to the approximate size of the
area being treated. The apical border of the material
should extend 3 to 4 mm apical to the margin of the
defect & laterally 2 to 3 mm beyond the defect.
22. The occlusal border of the membrane should be
placed 2 mm apical to the cementoenamel
junction.
Suture the membrane tightly around the tooth
with a sling suture.
Suture the flap back in its original position or
slightly coronal to it, using independent sutures
interdentally and in the vertical incisions.
The flap should cover the membrane completely.
23.
24.
25. Postoperative considerations
Peridox mouthwash should be given for 10 days
and if the material becomes exodontia, Peridox
should be used untill removal.
Antibiotic coverage (7 to 10 days)
Tetracycline 250 mg q.i.d.
Doxycycline 100 mg b.i.d.
Use of periodontal dressing is optional.
26. Flossing at the treatment site is to be avoided while
material is in place.
The patient should be seen biweekly if there is no
exposure & weekly if exposure is present.
Do not attempt to cover the previously exposed
material.
The material should be removed immediately if any
complication develops.
27. CONCLUSION
Guided tissue regeneration as a procedure
attempt regeneration through differential tissue
responses.
It concluded that GTR was not an experimental
procedure & that is showed predictability for
connective tissue attachment in infra bony defect
& in grade 2 furcation involvement.