guided tissue regeneration in endodontics
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Guided tissue regeneration in Guided tissue regeneration in endodontic surgeryendodontic surgery
Regeneration of periodontal defects involves formation of new cementum, new attached periodontal fibers and new bone in a region previously destroyed by periodontal disease.
In principle, In principle, four methods four methods have been described have been described totoincrease the rate of bone formation and to increase the rate of bone formation and to augmentaugmentthe bone volumethe bone volume: osteoinduction : osteoinduction by the use of appropriatby the use of appropriate e growth factors growth factors osteoconductionosteoconduction,,where a grafting material serves as a scaffoldwhere a grafting material serves as a scaffoldfor new bone growth for new bone growth distraction distraction osteogenesisosteogenesis,,by which a fracture is surgically induced andby which a fracture is surgically induced andthe two fragments are then slowly pulled apartthe two fragments are then slowly pulled apartand finally, and finally, guided tissue regenerationguided tissue regeneration, , whichwhichallows spaces maintained by barrier allows spaces maintained by barrier membranes tomembranes tobe filled with new bonebe filled with new bone
Guided tissue regenerationGuided tissue regeneration
The use of membranes to guide bony tissue formation by separating the underlying bone from Nonosseous cells (epithelial cells and fibroblasts)
and space is preserved between the bone surface
and membrane. Osteoblasts derived from the periosteum and bone are selectively induced on the osseous
defect area, facilitating new bone formation.
Guided tissue regeneration:
involves the placement of a barrier membrane to prevent cells other
that PDL cells from migrating first to root surface
Guided bone regeneration:
involves the placement of a barrier membrane and a bone graft
in the periodontal defect. Aim is to enhance bone formation
While GTR is for the regeneration of periodontal
tissue of
natural teeth GBR is for the regeneration
of supporting bone
Historical review of GBRHistorical review of GBR
Regeneration of alveolar bone beneath
cellulose acetate filler implant
- by Boyne PJ.
1964
Healing of bone defects by GTR
- by Dahlin C et al.
1988
Historical review of GBRHistorical review of GBR
Bone formation utilizing titanium-reinforced barrier membrane
- by Jovanovic. 1995
Augmentation of intramembraneous bone beyond the skeletal envelope using an occlusive titanium barrier
- by Lundgren D. 1995
Requirement of Requirement of GBR barrier membraneGBR barrier membrane
Biocompatibility & safety
Cell occlusiveness
Space-making ability
Tissue integration
Clinical manageability & cost effectiveness
- by Teparat T et al. 1998
Indication of GBRIndication of GBR
Extraction site
- Prevention of crestal bone loss
especially when 1 or more wall missing
Correction of inadequate ridge width or shape
- Atrophic alveolar bone reconstruction for implant
placement
Indication of GBRIndication of GBR
Dehicence defects
Apical fenestration
Residual intraosseous defects
- Fresh or incompletely repaired extraction
site
Nonresorbable membraneNonresorbable membrane
Titanium-reinforced expanded
polytetrafluoroethlene(Gorete)
Resorbable membraneResorbable membrane
Collagen barriers
- Bio-Guide, Bio-Mend, Colla Tape
Synthetic polymers
- Vicryl Mesh, Resolut, Resolut XT
Resorbable membraneResorbable membrane
Biologically active membrane:
Platelet-rich plasma
Other barrier materials
- Capset, Lambone
Bio-Gide: Composite Porcine Collagen Membrane
Bio-Oss:XENOGRAFT
Protein extraction of bovine bone to produce porous bone mineral hydroxyapatite
Decalcified Freeze- Dried Bone (D.F.D.B.)Decalcified Freeze- Dried Bone (D.F.D.B.)
Variable osteogenic capacity
Viral particles killed in processing
Limited success in furcations
Available in particles and putty
BMPBMP
Highest concentrations
of BMP gave best clinical results
endodontic-periodontal lesion is a clinical manifestation of the pathologic inflammatory intercommunication between pulpal and periodontal tissues via open structures such as apical foraminalateral, accessory canals, and dentinal tubules
,
primary endodontic lesions, primary endodontic lesions withsecondary periodontic
involvement
primary periodontic lesionsprimary periodontic lesions with secondary endodontic
involvement, true combined lesions
Simon et al classified Simon et al classified endodontic-periodontal lesions endodontic-periodontal lesions
intointo
The treatment of endodontic-periodontal combined lesions requires both endodontic therapy and periodontal regenerative
procedure. The success rate of the endodontic-periodontal combined lesion without a concomitant regenerative procedure has been reported to range from 27%–37% (Hirsch JM1985). This is significantly lower than the reported success rate of 95% with conventional nonsurgical root canal therapy (imura 2007)
Guided tissue regeneration (GTR) therapy introduced in 1980s has been widely used to regenerate lost periodontium from periodontal disease. Both human and animal studies have
demonstrated various degrees of regeneration of bone and attachment apparatus (Nyman S, Gottlow J, Karring T,
Lindhe J.1982). GTR therapy has also been implemented in the endodontic surgeries as a concomitant treatment during
the management of the endodontic-periodontal lesions (Schwartz 2006).
A treatment strategy for the application of the A treatment strategy for the application of the regenerative regenerative
procedures is outlined in Fig. 1 on the basis of theprocedures is outlined in Fig. 1 on the basis of the 26 successful cases reported (Schwartz SA, Koch MA 26 successful cases reported (Schwartz SA, Koch MA
2006) .2006) .
1. Treatment algorithm for periodontic-endodontic combined lesions
The presurgical assessment includes establishing and verifying the nonvital status of the pulp, the extent and severity of the periodontal destruction,. A localized deep probing depth with minimal tooth mobility might have a favorable clinical outcome after the regenerative procedure
Cortellini et al (2001) and others (Schulz A, Hilgers RD, Niedermeier W. 2004) have advocated splinting of the mobile
tooth before GTR procedure because the baseline mobility
has been associated with the smaller clinical attachment gain observed after GTR.
The intrasurgical assessment includes: morphology of the periodontal defect, defect type, material of choice to fill the defect and augment
healing, wound stabilization
combination autogenous bone graft and e-PTFE membrane
has been shown to result in the most favorable regenerative
outcome
A 50-year-old healthy, nonsmoker female Overall periodontal status was stable. tooth #3 showed a localized deep probing depth of 9 mm and a 5-mm gingival recession on the mesiopalatal aspect
of the tooth with grade II mobility. y. It responded to neither the electrical pulp test (EPT) nor
the cold test
no pain on percussion test Periapical radiographic views showed a deep vertical
bony defect extending to root apex of tooth #3, in addition
to the periapical radiolucencies to the mesiobuccal root
Initial diagnosis was pulp necrosis and asymptomatic apical periodontitis, and the tooth was thought to have primary
endodontic
involvement. However, the pattern of periodontal bone loss, with a wide base coronally and narrow extent apically,suggested that there was also primary periodontal involvement in this case. Therefore, the overall classification of this case was an endodontic-periodontal combined lesion.
• RCT,SRP during control phaseGTR after 1 month
Radiographic evidence of bone fill post surgery is not reliable
because of variation in angulation of X-ray beam and variations in processing film between preoperative and
postoperative radiographs.