PERIODONTAL REGENERATION. REGENERATIVE MECHANISM IN THE BRANCH OF PERIODONTOLOGY.

1. PERIODONTAL REGENERATION
GUIDED BY – DR. MONIKA MAM
PRESENTED BY – DR. AMRITA DAS
PG 2 ND YEAR.
DEPARTMENT OF PERIODONTOLOGY ,
JAIPUR DENTAL COLLEGE.

3. A BRIEF REVIEW WITH PERIODONTAL
REGENERATION..!!!

4. • Two techniques are with the most powerful
documentation for Periodontal Regeneration are
osseous grafting and Guided Tissue Regeneration (GTR)
.
• Although some procedures of regeneration may occur
regenerative procedure , it is not always predictable
and complete regeneration may be unrealistic goal for
many clinical situations .
• The article describes the biologic basis and clinical
applicability of osseous grafting and GTR and the
biologic developed modifiers that show promising
result in periodontal regeneration.

5. SOME TERMS…
• Now coming to the definitions ,
• REGENERATION refers to the reproduction or reconstitution
of lost or injured tissue.
• PERIODONTAL REGENERATION refers to the restoration of
lost periodontium or supporting tissues and includes
formation of new alveolar bone , new cementum and new
periodontal ligament.
• REPAIR : refers to the healing of a wound by tissue that
does not restore fully the architecture and the function of
the part .
• NEW ATTACHMENT : is defined as the union of connective
tissue or epithelium with a root surface that has been
deprived of its original attachment aparatus.

6. • REATTACHMENT : describes the reunion of
epithelial and connective tissue with a root
surface.
• GTR : describes procedure attempting to
regenerate lost periodontal structures through
differential tissue response and typically refers to
regeneration of periodontal attachment.
• Barrier techniques are used for excluding
connective tissue from the formation of new new
periodontal ligaments.

7. • BONE FILL : It is defined as the clinical restorations of
bone tissue in a treated periodontal defect . Bone fills
does not address from the presence or absence of
histologic evidences of new connective tissue
attachment or the formation of new periodontal
ligaments.
• OPEN PROBING CLINICAL ATTACHMENT: is used to
describe the tissue seen at the rentry surgery after
regeneration procedures. This term is not been
commonly used because the clinical attachment
cannot be probed in the open environment.

8. BIOLOGIC FOUNDATION
• Surgical debridement and resective procedures
are the traditional surgical treatments used to
improve clinical disease parameters and arrest its
progression .
• Few reports of minimal invasive regeneration of
bone and the tooth supporting structure after the
therapeutic treatment have been described .
These methods typically heal by repairing ,
forming a combination of connective tissue
adhesion/ attachment for forming a long
junctional epithelium.

9. • The process of compartmentalization in which
the connective tissues of the periodontium are
divided into 4 compartments – the lamina propria
of the gingiva , the periodontal ligament, the
cementum, and the alveolar bone. – was
developed by Melcher in 1976 .
• From this concept of compartmentalization , the
GTR procedure developed and barrier
membranes were used to accomplish the
objectives of epithelial exclusion.

10. • Cell/tissue repopulationcontrol ,space
maintainance and clot stabilization is based on
exclusion of gingival connective tissue cells
and the prevention of downgrowth of wound.
• By the exclusion of these tissues, cells with
regenerative potential can enter into wound
site first and promote regeneration.

11. WOUND HEALING PRINCIPLES
• Research confirms that periodontal surgical
wounds go through the same sequence of healing
events as all incisional wounds. ; the formation of
fibrin clot between the flap margin and the root
surface and replacement of this fibrin clot by a
connective tissue matrix attached to the root
surface.
• When the fibrin linkage is maintained , it allows
for a new CT attachment to the root surface .

12. WOUND HEALING…WALL DEFECTS TO
BE HEALED THROUGH PERIODONTAL
REGENERATION

13. • In the case of fibrin linkage being disrupted , a
long junctional epithelium type attachment
results.
• Regenerative failures may be as a direct result of
tensile of fibrin clot being exceeded , resulting in
a tear.
• The potential cause of this tear is mobility of the
flap and its wound margin adjacent to the
potential regenerative site.
• During the healing of the wound, there is a
specialized cells types and attachment complexes

14. • Stromal cellular interactions, diverse microbial
flora , and the avascular tooth that complicate
the process of periodontal regeneration .
• More predictable outcomes following GTR
procedure will be achieved as the principles
involved in the periodontal involved in the
periodontal wound healing process are better
understood.

15. TECHNIQUES FOR REGENERATION
• ROOT SURFACE CONDITIONING :root surface
conditioning with tetracycline or citric acid has
been used as a part of regenerative procedures.
Root surface conditioning was originally
suggested because of the ability of acid to modify
the root surface by detoxifying it.
• Root surface conditioning also showed that
collagen fibrils were exposed within the
cementum or dentin matrix .

16. • Although animal studies demonstrated new
connective tissue attachment following acid
demineralization, histologic evaluation in human
clinical trials demonstrated limited connective
tissue attachment and limited regeneration
following citric acid demineralization. Recent
studies showed that using EDTA, which has a less
acidic ph, may also expose collagen fibers and
thus promote cell attachment without having a
damaging effect on the surrounding tissues.

17. • Results from clinical trials using any type of
root conditioning agent indicates no
additional improvement in clinical conditions .
A recent meta analysis systemic review
confirmed that use of citric acid , tetracycline
or EDTA to modify the root surfaces provides
no clinically significant benefit of regeneration
in patients with chronic periodontitis.

18. HOW IS IT DONE IN PERIODONTAL
RENGENERATION…??

19. SEE HOW THE DEFECTS HAVE BEEN
FILLED UP THROUGH BONE
REGENERATION…

20. DISEASED PERIODONTIUM TO
REGENERATION OF PERIODONTIUM

21. CORONALLY POSITIONED FLAP
• The periosteum is viewed as having regenerative
potential due to its rich structure in osteoproginetor
cells. The regenerative potential is thought to be result
from combination of cellular activity of the periosteum
. When the coronally positioned flap are used to treat
mandibular class 2 furcation defects, the position of
the flap margin is away from the critical healing area (
the furcation site) and secured. An approximate of
bone fill in class 2 mandibular furcation defects has
been reported in studies that perform reentry
surgeries. It is necessary to test a larger number of
patients with a longer follow up period to fully evaluate
this technique.

22. BONE GRAFT
• Bone replacement grafts include the autografts,
allografts, xenografts, and allografts. Bone replacement
grafts are the most widely used treatment options for
the correction of periodontal ossous grafts. It has been
proved that bone replacement grafts provides clinical
improvement in periodontal osseous defects compared
with surgical debridement alone. For the treatment of
intrabony defects , bone grafts have been found to
increase the bone level, reduce crestal bone defects ,
increases clinical attachment level, and reduce pocket
probing depth compared with pocket probing depth.
Their benefits for the use of furcation defects remains
for the debridement.

23. EXTRAORAL AND INTRA ORAL DONOR
SITES FOR AUTOGENOUS BONE
GRAFTS
• Due to their osteogenic potential, autogenous
bone grafts of extra oral intra oral bone grafts
sources have been used in periodontal therapy.
Iliac graft have been used in periodontal therapy
and is used as frozen and fresh. Succesfull bone
filling has been demonstrated using iliac
cancellous bone with marrow furcations,
dehioscence and intra oral defects. One common
complication is root resorption during using fresh
grafts. Other demerit is its morbidity.

24. • The maxillary tuberosity or a healing extraction site is
typically the donor choice for intraoral cancellous bone
with marrow cells grafts. Intraosseous defects grafted
with intraoral bone have demonstrated bone fill equal
to that obtained with iliac grafts . A mean bone fill
ranges from 1.2 to 3.4 mm has been reported with
intraoral grafts. Other techniques reports bone fill
using cortical bone chips and osseous coagulum or
bone blend type grafts. Studies reveal histologic
regeneration and new connective tissue attachment
and the presence of long junctional epithelium
following these procedures.

25. ALLOGENIC BONE GRAFTS
• Allografts involve bone taken from one human for
transplantation to another. Iliac bone and
marrow , freezr dried bone allograft and
decalcified FDBA are the types of bone grafts
widely used and available from commercial tissue
banks. Grafts taken from cadaver and typically
FDBA and treated to prevent disease
transmission. Typically frozen iliac allografts are
not used due to the need for extensive cross
matching to decrease the likelihood of graft
rejection and disease transmission.

26. FREEZE DRIED BONE ALLOGRAFTS
• FDBA works primarily through osteoconduction . The
graft does not activate bone growth but acts like a
scaffold for natural bone to grow into. Eventually the
graft is resorbed and replaced by new bone. Freeze
drying the bone decreases the antigenicity of the
allograft. Radiographically , FDBA appears radioopaque
because it is not demineralised.
• When treating FDBA to treat periodontal defects ,
trialsv indicate bone fills ranging from 1.3 to 2.6 mm.
• Using a combination of FDBA with tetracycline has also
shown promise in the the treatment of defects
resulting from juvenile periodontitis.

27. DEMINERALIZED FREEZE DRIED BONE
ALLOGRAFT
• Urist showed that demineralization FDBA was
osteoconductive . DFDBA is believed to induce
bone formation due to influence of bone
inductive proteins called as BMP. Which is
called as Bone Morphogenic Proteins exposed
during Demineralization process. DFDBA is
thought to be osteoconductive and
osteoinductive.

28. • DFDBA has demonstrated periodontal
regeneration in controlled human studies.
Significant more regeneration was achieved with
DFDBA than in nongrafted controls. Superior
gains in bone fill with DFDBA compared with
open flap debridement have consistently been
reported.
• According to the dealers, DFDBAmay vary from
batch to batch. Some studies suggest that
quantity of BMP is too small to induce bone
formation

29. • Some studies suggest that the quantity of BMPS
is too small to induce bone formation and that
bone formation occurs by other process.
Commercial bone banks do not verify the specific
amount of BMPS or the levels of inductive
capacity in any graft material. The developement
of stricter bone bank standard evaluate potency
of their preparation. Including using of bones
from indivisual which may lead to more
consistent and reliable clinical result.

30. HUMAN MINERALISED BONE
• Puros is a new allogaft of cancellous bone on the
market. It is human bone that undergoes tutoplast
process involving 1. delipidization with acetone and
ultrasound. 2. osmotic treatment 3. oxidation with
hydrogen peroxide to destroy unwanted proteins. 4.
solvent dehydration with acetone to preserve the
collagenous fiber structure 5. low dose gamma
irradiation . Manufactures believe that this new solvent
preservation method preserves the trabecular pattern
and mineral structure better than the freeze drying
process thus being more osteocoductive material.

31. GRAFTON DEMINERALIZED BONE
MATRIX ( DBM)
• Grafton DBM is processed from Cadavers long
bones by aseptically processing the bone to
remove lipids , blood and cellular components.
Cortical bone is milled and cellular components
of 0.5 mm in diameter or pulverized into particles
of 100 – 500 um.
• It is combined with a glycerol carrier to stabilize
the proteins and improve graft handling. It can be
used in the flex form, as putty, or as matrix plugs.

32. ALLOPLASTS
• Alloplastic materials are synthetic , inorganic,
biocompatible, or bioactive bone grafts
substitutes. Alloplast materials are believed to
promote, bone healing through osteoconduction.
• Currently 6 types of alloplastic materials are
commercially available , hydroxyappetite, non
porous materials , porous hydroxyappetite , beta
tricalcium phosphate , PMMA / HEMA , calcium
layered polymer and bioactive glass.

33. • Ideally, alloplast bone substitutes should have
the following properties, 1. biocompatible,
minimal fibrotic reaction , the ability to
undergo remodelling and support new bone
formation. Similar strength comparable to
cortical/ cancellous bone and similar modulus
of elasticity comparable to bone to prevent
fatigue under cyclic loading.

34. • Bioactive glass is made from calcium salts,
phosphate , sodium salts and silicon . Silicon
forms a silicon gel layer that promotes
formation of hydroxyappetite layer. Overall
histologic evaluation of bioactive glass shows
limited regenerative propertieswith minimal
bone regeneration and no signs of new
cementum or periodontal ligaments.

35. XENOGRAFT
• A xenograft is a graft taken from a donor of
another species and is referred as anorganic
bone.
• Propertiery process are suggested to remove all
cells and proteinaceous material. What is left
behind is inert absorbable bone scaffold.
• In this scaffolding that revascularization ,
osteoblast migration , and woven bone formation
supposedly occur .
• Resorption of xenografts have been reported to
occur very slowly.

36. • To date, there are minimal clinical data
supporting the use of xenograft in periodontal
defects. Signs of periodontal regeneration
have been reported with xenografts. Positive
clinical outcomes were reported when the
combination of bovine hydroxyappetite and
collagen membrane was used to treat the
intrabony defects.

37. GUIDED CELL REPOPULATION/ GUIDED
CELL REGENERATION
• The concept of GTR is based on the exclusion of
gingival connective tissues cells and prevention of
epithelial growth into the wound. ,thereby
allowing cells with regenerative potential to enter
the wound first.
• GTR has been proved to be more effective than
open flap debridement in the gain of of clinical
attachment and probing depth reduction in the
treatment of intrabony and furcation defects.

38. • Absorbable and non absorbable membranes
have been advocated and no difference have
been detected among barrier types.
• Because non resorbable membranes requires
a second surgical procedure for removal of
biodegradable membranes and are new
commonly used.

39. ABSORBABLE MEMBRANE
• Currently , polylactic acid and collagen membrane have
reporeted clinical improvements comparable to non
absorbable membrane.
• The main advantage of absorbable membranes is that
they do not require a second surgical procedure.
• Collagen membranes are also effective in inhibiting
epithelial migration and promoting new connective
tissue attachment . An advantage of collagen
membrane is their haemostatic function of inducing
platelet aggregration , which facilitates early clot
formation and wound stabilization.

40. NON ABSORBABLE MEMBRANES
• The first membrane available was made of
expanded polytetraflourorthylene. This
membrane is composed of two parts : a coronal
collar with an open microstructure allowing
growth of connective tissue but preventing apical
migration of the epithelium and the remaining
occlusive part that prevents the gingival tissue
from interfering with the healing procedure at
the root surface. Results tend to approximate
varying on the type of defect treated. Three wall
defects typically respond the best.

41. • The treatment of furcation defects with
combination of GTR barriers and bone
replacement grafts appears to produce
greater clinical improvement than GTR alone.

42. ABSORBABLE MEMBRANE
• Currently , polylactic acid, and collagen
membranes have reported clinical improvements
comparacle to non resorbable membranes.
• The main advantage of absorbable membrane is
that they do not require a second surgical
procedure.
• Collagen membranes are also effective in
inhibiting epithelial regeneration migration and
promoting new connective tissue attachment.

43. • An advantage of collagen membranes is their
haemostatic function of inducing platelets
aggregation, which facilitates early clot
formation and wound stabilization are
essential for successful regeneration. Collagen
also processes chemotactic functions for
fibroblasts that will aid in cell migration to
promote primary wound closure and
stabilization.

44. • When using bone replacement grafts and
absorbable sutures and collagen membranes ,
clinical results are improved in furcation but
not in intrabony defects.
• Degradable polymers of polylactic acids,
polyglycolic acid, or mixture of both have had
similar clinical results are improved in
furcation but not in intrabony defects.

45. BIOLOGIC MODIFIERS
• BONE MORPHOGENIC PROTEINS :
• They have unique properties in inducing ectopic
bone formation and new connective tissues of
cementum formation. Several animal research
studies reported improved regenerative
properties results when BMP 2 and BMP 7 were
used for the treatment of periodontal defects .
Future research is needed to clearly understand
the applicability of BMP in periodontal
regeneration .

46. GROWTH FACTORS/ CYTOKININS
• Transforming Growth Factors B , platelet derived
growth factors , insulin like growth factors, and
fibroblast growth factors and fibroblast growth
factors act as nitrogen or differential factors on
regenerating periodontal tissues . Limited human
clinical data are available. One human clinical
derivated trial using recombinant platelat
derived growth factors and insulin like growth
factors has shown promising results in intrabony
defects and furcation.

47. • Another study showed that the use of purified
recombinant human platelet derived growth
factors BB mixed with bone allograft results in
robust periodontal regeneration in class 2
furcation and intrabony defects . Most studies
are needed to fully evaluate the potential of
growth factors for enhancing periodontal
regeneration.

48. OTHER EMERGING MATERIALS
1) ENAMEL MATRIX DERIVATIVE :
Enamel derivative protein appears to be offer some
potential for regenerative therapy around natural
teeth .
2. FREEZE DRIED PROTEINS : In a propylene glycol alginate
solution. This solution is to be applied and
conditioned in a periodontal infrabony defect.
Although revent studies indicates its mean probing
measurements and radiographic evidence with bone
fill but with long term benefits have not been
benefited.

49. • PEP – GEN – P 15 has been recorded as a new
additional studies.
• Pep-Gen p-15 is another material recently introduced
for periodontal
• regeneration. It is a putative collagen-binding
peptide that uses a combination
• of an anorganic bovine-derived hydroxyapatite
matrix and a synthetic
• 15–amino acid sequence type I collagen (P-15) [115].
P-15 is a collagen derived cell binding proteins. That
is advised to attract and bind and attract fibroblast

50. And osteoblast to promote periodontal
attachment to bovine induced
hydroxyappetite matrix carrier. Few clinical
trials have reported greater regeneration
compared with open-flap debridement.
Additional clinical and histological data are
needed to true periodontal regeneration using
this material.

51. FACTORS AFFECTING REGENERATION
THERAPY
• The number of bony walls, and depth of intrabony defects are
critical for positive GTR regeneration. Defects with 3 walls
defects or 4mm or more achieve the best results.
• Thin clinical tissues have been showed up the less clinical
results and less improvement of percentage of root coverage.
• The best results have been seen in healthy patients, non
smokers demonstrating good plaque control and compliance
with oral hygiene.
• The effects of bacterial contamination have been noted in the
studies of inverse relationship of observed plaque control and
clinical attachment gain.

52. • Indications and contraindications for guided
tissue regeneration:
• INDICATIONS :
• Narrow 2- or 3-wall infrabony defects
• Circumferential defects
• Class II molar furcations
• Recession defects

53. • CONTRAINDICATIONS
• Any medical condition contraindicating surgery
• Infection at defect site
• Poor oral hygiene
• Smoking (heavy)
• Tooth mobility >1 mm
• Defect <4 mm deep
• Width of attached gingiva at defect site •1 mm
• Thickness of attached gingiva at defect site •0.5 mm
• Furcations with short root trunks
• Generalized horizontal bone loss
• Advanced lesions with little remaining support
• Multiple defects

54. PERIODONTAL DESTRUCTION TO
PERIODONTAL REGENERATION

55. SURGICAL APPLICATION
• FURCATION DEFECTS .
• INTRABONY DEFECTS
• GINGIVAL RECESSION DEFECTS

57. SUMMARY
• Several options are available for GTR and grafting materials.
Many
• critical factors are involved to achieve optimal results, such as
case selection
• flap management, patient management, technique, and graft
selection
• Clinicians need to be able to select the proper cases for the
appropriate
• treatment and use the appropriate graft material when
indicated.