This document discusses reconstructive osseous surgeries and periodontal regeneration. It begins with definitions of key terms like repair, reattachment, new attachment, and regeneration. It then covers the history of periodontal regeneration research, including experiments demonstrating the regenerative potential of different progenitor cell sources. The document outlines the biology of wound healing and variables that influence periodontal regeneration. It also discusses methods of evaluating new attachment and periodontal reconstruction outcomes, including clinical, radiographic, surgical re-entry, and histological methods. Finally, it covers regenerative techniques like removal of junctional epithelium and root bio-modification to facilitate new attachment.

1. RECONSTRUCTIVE OSSEOUS
SURGERIES
DR. ACHI JOSHI
SRI AUROBINDO COLLEGE OF DENTISTRY, INDORE
1

2. CONTENTS
1. Introduction
2. Definitions
3. History
4. Biology of regeneration
5. Non- graft associated
regeneration
6. Bone grafts
2

3. INTRODUCTION
• Periodontitis is an inflammatory disease that causes
pathological alterations in the teeth and their supporting
tissues, potentially leading to tooth loss.
• The major challenges in contemporary periodontal therapy are
to establish soft tissue attachment to newly formed cementum
on the root surface and to restore lost bone. This requires
regeneration of gingival connective tissue destroyed by
inflammation, formation of new cementum and restoration of
bone loss and most importantly, new attachment of connective
3

4. DEFINITIONS
• Repair
Healing of a wound by tissue that does not fully restore the
architecture or function of the part, as in the case of a long
junctional epithelium or ankylosis.
4

5. Reattachment
To attach again. The reunion of epithelial and connective tissue
with root surfaces and bone such as occur after an incision or
injury. (Lit review)
The reunion of connective tissue with a healthy root surface on
which viable periodontal tissue is present without new
cementum, as in the case of trauma or after a supra-crestal
fiberotomy. (Cohen) 5

6. Healing by long
junctional epithelium.
The bone is new but the periodontal ligament is not.
6

7. New attachment
The reunion of connective tissue with an unhealthy or previously
diseased root surface that has been deprived of its original
attachment apparatus. This new attachment may be epithelial
adhesion and /or connective adaptation or attachment and may
include new cementum. (Lit review)
Enamel surface
Area of
cementum
denuded by
pocket
formation
cementum
covered by JE
New attachment
refers to a new
junctional
epithelium and
attached
connective tissue
fibers
formed on zone B.7

8. • Regeneration
Reproduction or reconstitution of the lost or injured parts by
restoration of new bone, cementum, and a periodontal ligament
(reunion of connective tissue) on an unhealthy or previously
diseased root surface. Ideally, complete restoration would also
restore total function. (Cohen)
8

9. PERIODONTAL RECONSTRUCTION
Periodontal reconstruction to refer to the process of regeneration
of cells and fibers and remodeling of the lost periodontal
structures that results in
1. Gain of attachment level,
2. Formation of new periodontal ligament fibers, and
3. A level of alveolar bone significantly coronal to that present
before treatment.
9

10. BONE FILL
• Bone fill is defined as the clinical restoration of bone tissue in a
treated periodontal defect. Bone fill does not address the
presence or absence of histologic evidence of new connective
tissue attachment or the formation of new periodontal
ligament.
10

11. • There are five main categories of therapeutics used or in
development for tissue regeneration -
1. A conductive therapeutic is a biocompatible scaffold that
guides the regeneration of the tissue by passively allowing
the attachment and growth of vascular elements and
progenitor stem cells that reside in the tissue defect. Its
regenerative potential is limited by the lack of biologically
active factors and sufficient progenitor cells within the
defect. Ex:hydroxyapatite, tricalcium phosphate, and calcium
sulfate fillers.
11

12. • An inductive therapeutic is a biocompatible scaffold that guides
the regeneration of the tissue by carrying one or more
biologically active factors that recruit vascular events and
progenitor stem cells from the immediate vicinity to the tissue
defect. Its regenerative potential is higher than the conductive
biomaterial because more progenitor cell can repopulate the
tissue defect. Examples allogenic bone grafts or biomaterials
carrying Osteoconductive recombinant proteins.
12

13. 3. A cell-based therapeutic is a biocompatible scaffold that
contains progenitor stem cells or differentiated cells. The
cells are delivered within the tissue defect and become
tissue-forming cells. Ex Bone autografts.
4. A gene-based therapeutic is a biocompatible scaffold
carrying single or multiple genes that transform the non-
progenitor cells already present within the tissue defect into
both progenitor and mature tissue-specific cells. A gene
therapy product is able to signal the cells present in the
defect to differentiate into a phenotype more favorable to the
regenerative process, and it represents an attractive solution
13

14. 5. A RNA-based therapeutics may be considered a fifth category
of regeneration therapy even though this approach remains in
the conceptual stage of development. They are based on the
principle of RNA interference (RNAi), a novel mechanism of
action by which RNAs silence gene expression. Novel
therapeutics may be envisioned whereby the expression of
certain genes detrimental to the tissue regeneration process
is silenced by RNAs.
14

15. HISTORY
15

16. HISTORY OF REGENERATION
BACTERIAL INFECTION
BONE DESTRUCTION
RESECTION REGENERATION
16

17. • Melchar (1976) described for periodontal regeneration
progenitor cell population can be derived from four sources-
1. Cells derived from gingival connective tissue
2. Cell derived from alveolar bone
3. Cells derived from periodontal ligament
4. Cells derived from cementum
17

18. EXPERIMENTS TO DEMONSTRATE
PROGENITOR POOL
18

19. BONE
KARRING ET AL (1980)
• Induced periodontal tissue breakdown in the beagle dog by
applying cotton floss ligatures.
• When the destruction of the supporting tissues had progressed
to a level corresponding to half the root length, the ligatures
were removed and the teeth were cleaned.
• Mucoperiosteal flaps were raised.
• The exposed parts of the roots were thoroughly scaled and
polished.
19

20. • The crowns of the teeth were cut off and the level
of the marginal bone crest was marked by
preparing a notch in the root surface.
• The roots were carefully extracted and
transplanted into surgically created alveolae in
edentulous parts of the jaw. The roots completely
surrounded by bone, were covered by a soft tissue
flap.
20

21. • After 3 months of healing, connective tissue reattachment was
found in the apical part of the roots, where a viable periodontal
ligament was preserved, whereas in the coronal part, where the
roots had been exposed to periodontitis and the original
periodontal ligament was removed, ankylosis and root
resorption were the dominant features
• The results of indicated that cells derived from bone lacked the
potential to produce new attachment.
21

22. GINGIVAL CONNECTIVE TISSUE
Nyman et al (1980)
• The teeth were transplanted and placed in such a way that only
half of their circumference was located in contact with bone,
and the other half was in contact with the gingival connective
tissue of the covering soft tissue flap.
22

23. • Histological analysis showed that the part of the root surfaces
facing the gingival connective tissue exhibited as much root
resorption as the part facing bone tissue.
• It was concluded that gingival connective tissue lacks the
potential to induce the formation of new connective tissue
attachment to a root surface that has been deprived of its
original periodontal ligament.
23

24. • Formerly described studies demonstrated that root resorption
and ankylosis were occasionally also found in certain areas of
the apical portion of the roots. This finding indicated that the
periodontal ligament in such areas had become traumatized
when the teeth were extracted and transplanted.
• This was confirmed by a study conducted by Karring et al 1985.
24

25. PERIODONTAL LIGAMENT
• Karring et al (1985) examined whether a new connective tissue
attachment was form on previously periodontitis involved roots
when reduced but healthy periodontal ligament tissue persists
following periodontal treatment.
• Experimental periodontitis was produced, after 50% of bone
loss, periodontal treatment was done to remove pocket
epithelium and granulation tissue.
• The crowns were resected and roots were covered with mucosal
flap. 25

26. • Histological examination after 3 months, revealed that new
cementum with inserting collagen fiber had formed in apical
portion of previously exposed root surface. It was in continuity
with original cementum layer apical to the instrumented part of
the root and was thickest in its apical portion becoming
gradually thinner in coronal direction.
• It was also found that in some areas where epithelium got
access to root surface, it grew apically on the root surface
hindering the new connective tissue attachment.
26

27. • So, the results of the study demonstrated that new attachment
was formed by coronal migration of cells originating from
periodontal ligament and proliferation of epithelial cells should
not be allowed on root surface to achieve new connective tissue
attachment.
27

28. ROLE OF EPITHELIUM
• Periodontal defects were created by placing orthodontic elastics
around experimental teeth.
• The defects were treated in 4 different ways:
• The modified widman flap procedure
• Modified widman flap +implantation of previously frozen autogenous red marrow
and cancellous bone,
• Modified widman flap+ implantation of a bone substitute, beta tricalcium
phosphate and
• Root planing and soft tissue curettage.
Histometric measurements demonstrated that all treatment procedures resulted
in the reformation of an epithelial lining (long junctional epithelium) facing the
instrumented root surfaces, with no new connective tissue attachment.
28

29. • It was concluded that epithelial down- growth prevents the
formation of a new connective tissue attachment by preventing
repopulation of the root surface by cells derived from the
periodontal ligament.
• The coverage of the root surface by an epithelial layer also has
a beneficial effect  the prevention of root resorption and
ankylosis, which otherwise could be induced by gingival
connective tissue and bone.
29

30. BIOLOGY OF REGENERATION
30

31. HEALING- INFLAMMATORY PHASE
1. Hemostasis is achieved in 24-48 hrs.
2. Exposed collagen  clotting cascade clot formed  fibrin
mesh  matrix for fibroblast and other cells.
3. growth factors  chemotaxis and proliferation of neutrophils.
31

32. 4. Macrophages and neutrophils  gelatinase and stromelysis 
removes debris from ECM
5. Vascular endothelial cells migration of angiogenic cytokines
( i.e. VEGF, TGF- alpha , TGF – beta ,TNF-alpha, FGF
6. Around 48-96 hr after injury, monocyte  macrophages  IL
4, IL -5, IL -8, IL-12, IL-15.
32

33. 33

34. PROLIFERATIVE PHASE
• Epithelization, angiogenesis, granulation tissue formation,
collagen deposition takes place.
1. Fibroblasts are the dominant cells, these migrate into wound
space and proliferate. Proliferation is influenced by PDGF,
FGF, EGF.
2. Collagen deposition starts at 3-4 days and is positive until
day 21.
3. Collagen remodeling starts. 34

35. REMODELING PHASE
• Connective tissue remodeling and bone remodeling is the last
phase of wound healing.
• It begins at 2-3 weeks and may last up to 2 years.
35

36. BIOLOGY OF REGENERATION
• Periodontal surgical wounds go through the same sequence of
healing events as all incisional wounds: the formation of a 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
connective tissue attachment to the root surface. In the case of
the fibrin linkage being disrupted, a long junctional epithelium–
type attachment results. 36

37. • During the healing of periodontal wounds, there is the
presence of multiple specialized cell types and attachment
complexes, stromal–cellular interactions, diverse microbial
flora, and avascular tooth surfaces that complicate the process
of periodontal regeneration.
37

38. WOUND HEALING VARIABLES
1. Progenitor cells.
2. Alteration of pathologically exposed root surface.
3. Exclusion of gingival epithelium from wound.
4. Wound stabilization.
5. Technical aspects.
38

39. EVALUATION OF NEW ATTACHMENT AND
PERIODONTAL RECONSTRUCTION
1. Clinical methods
• Comparison of pre treatment with post treatment periodontal
parameters like probing depth, CAL, bone level etc.
• Measurement of defect by probing with help of grooving stent for
same angulations of probe before and after treatment.
DISADVANTAGES-
Gives only probing depth reduction not the connective tissue level.
39

40. 2. Radiographic methods
• Assessment of bone tissue in the defect before and after
treatment.
• This measurement influences by type of technique, tube and
film potions.
• Radiograph does not show the entire topography of the area
before and after treatment.
DISADVANTAGES
Gives only level of bone, not if periodontal ligament is present
between tooth and bone.
“ bone fill ≠ regeneration”
Little information on the nature of attachment and density of
bone.
40

41. CBCT
CBCT precision in alveolar bone density measurement:
• Radiographic follow-up of bone healing after grafting is
challenging because of the overlapping of gaining and losing
areas within the graft. CBCT offers an opportunity to see inside
the bone and pinpoint and measure densities in small localized
areas such as a vertical periodontal defect or an alveolar bone
graft. This precision would make it possible to reproducibly
quantify the bone remodeling after bone grafting.
Cohenca N, Simon JH, Roges R, Morag Y, Malfaz JM. Clinical indications for Digital imaging in dento-alveolar trauma. Part 1: traumatic injuries. Den Traumatol. 2007
41

42. 3. Surgical re-entry
• Re entry of treated defect after period of healing.
• Comparison of defect measurement before and after treatment.
• Its very useful method.
DISADVANTAGES
• 2nd procedure
• Does not show the type of attachment.
42

43. 4. Histological methods
• Type of attachment can be determined only by histological
analysis of tissue obtained from healed area.
• Clearly demonstrate new cementum, bone, Periodontal
ligament.
Disadvantage- it require removal of tooth with its periodontium.
43

44. Reconstructive techniques can be subdivided into two major
types:
• Non–bone graft–associated new attachment and
• Bone graft–associated new attachment
44

45. REMOVAL OF JUNCTIONAL AND POCKET
EPITHELIUM
• The presence of junctional and pocket epithelium act as a
barrier to successful therapy because its presence interferes
with the direct apposition of connective tissue and cementum,
thus limiting the height to which periodontal fibers can insert
to the cementum.
• Various methods to avoid JE and Pocket epithelium-
45

46. 1. CURETTAGE
• Results of removal of the epithelium by means of curettage vary
from complete removal to persistence of as much as 50%.
Therefore curettage is not a reliable procedure.
• Ultrasonic methods, lasers, and rotary abrasive stones have
also been used, but their effects cannot be controlled because
of the clinician’s lack of vision and tactile sense when using
these methods.
46

47. 2. CHEMICAL AGENTS
• Chemical agents have also been used to remove pocket
epithelium, usually in conjunction with curettage. The drugs
used most often have been sodium sulfide, phenol camphor,
Antiformin, and sodium hypochlorite. However, the effect of
these agents is not limited to the epithelium, and their depth of
penetration cannot be controlled.
47

48. PREVENTION OR IMPEDING THE EPITHELIAL
MIGRATION
• Elimination of the junctional and pocket epithelium may not be
sufficient because the epithelium from the excised margin may
rapidly proliferate to become interposed between the healing
connective tissue and the cementum.
48

49. ROOT BIO-MODIFICATION
• To achieve a biologically compatible root surface complete
removal of deposits and bacterial endotoxin is a pre-requisite.
Root bio-modification was done to facilitate new attachment by
root surface demineralization.
• Urist (1965) that suggested that dentin following acid
demineralization possessed inductive properties.
49

50. CITRIC ACID
• Registrar and Burdick (1975) studied several
demineralizing agents for optimum concentration and
time of application in gaining attachment.
• They tested- citric acid, lactic acid, HCl acid, formic
acid, it was determined that citric acid at pH 1 for 2-3
minutes would be best agent.
• It showed formation of cemental pins extending into
dentinal tubules widened by demineralization. 50

51. • Garnet et al (1978 and Lasho et al (1983) showed that acid etched
surfaces resulted in demineralized zone dominated by exposed
collagen fibers.
• Polson (1984) showed by SEM evaluation that root planing leaves a
amorphous layer 2-15 micron thick which consist of organic and
inorganic material when these surfaces were treated by citric acid, this
layer is removed resulting in a fibrous funnel shaped depressions
corresponding to open dentinal tubules.
• Hanes (1988) showed this collagen layer has active cells migrating over
root surface and concluded that citric acid application resulted in clot
stabilization and initiate wound healing thus results in new connective
51

52. STUDIES
Positive Clinical results –
• Cole et al (1981)
• Renvert and Edelberg (1981)
• Caffesse (1988)
citric acid + fibronectin
No effect-
Parodi and Esper ( 1984)
Renvert (1985)
Marks and Mehta (1986)
Smith et al (1986)
Moore et al (1987)
52

53. TETRACYCLINE
• In vitro treatment of the dentin surfaces with tetracycline increases
binding of fibronectin, which in turn stimulates fibroblast
attachment and growth while suppressing epithelial cell attachment
and migration.
• Tetracycline also removes an amorphous surface layer and exposes
the dentin tubules.
• Hanes et al., demonstrated that tetracycline conditioning of the root
surfaces will not only selectively remove the surface smear layer, but
may also act favorably by inhibiting collagenase activity and bone
resorption and by its local antimicrobial effects. 53

54. • In vivo studies, have not shown favorable results. A human
study showed a trend for greater connective tissue attachment
after tetracycline treatment of roots; tetracycline gave better
results when used alone than when combined with fibronectin.
• Optimum concentration of 100mg/ml to root surfaces for 3-5
min.
54

55. FIBRONECTIN
• Fibronectin is the glycoprotein that fibroblasts require to attach
to root surfaces.
• The addition of fibronectin to the root surface may promote
new attachment. However, increasing fibronectin above plasma
levels produces no obvious advantages.
• The optimum concentration has been shown to be 0.38mg/ml
saline.
55

56. • Smith et al. (1987) reported the effect of citric acid and
fibronectin on healing after periodontal flap surgery in
dogs. Results showed significant increase in new
connective tissue attachment in all surgical sites where
fibronectin had been applied.
• Exogenous application of fibronectin only has shown to
be of limited use however encouraging results have
been obtained with citric acid conditioning and
subsequent fibronectin application. Additional clinical
investigations are indicated to determine the place of
this treatment combination in periodontal therapy.
56

57. EDTA (ETHYLENE DIAMINE TETRA ACETIC
ACID)
• Studies (Pitaru et al , 1983,1987) have shown that root surface
demineralized by 18% EDTA facilitates the attachment, migration
and contraction of fibroblasts, which leads to development of an
oriented fiber attachment system between the demineralized
surfaces.
• Studies( Blomlof, Mayfiels, Krigger) examined the effect of 24%
EDTA with a pH between 7.0-7.2. The EDTA was applied to root
surfaces for 2-3 minutes. Results showed no difference in probing
depth, clinical attachment compared to root planing alone.
57

58. CHLORHEXIDINE
• Chlorhexidine applied to the root surface during surgical
treatment of bifurcation defects in 43 dogs resulted in no gain
in level of connective tissue attachment. (Crigger, 1978)
58

59. LASERS
CO2 LASER
• Misra et al (1999), showed that CO2 LASERS produced surface
charring and carbonization, and were totally ineffective in
exposing the dentinal tubules.
• A scanning electron microscopic study by Crespi et al in 2002
showed increased fibroblast attachment after root conditioning
in pulsed defocus mode.
• In contrast to this a histological study showed in vivo inhibition
of periodontal tissue attachment by residual char layer.
59

60. • Thus the CO2 laser, when used with high-energy output,
especially in a continuous wave mode, is not appropriate for
root surface debridement due to major thermal side-effects,
such as carbonization. (Gopin, 1997) However, when used with
relatively low energy output in diseased root a pulsed and/or
defocused mode, this laser may have root conditioning,
detoxification and bactericidal effects on contaminated root60

61. Nd:YAG
• Nd:YAG laser have shown its efficacy in removing the smear
layer and inactivating the endotoxin in the superficial layer of
the root surfaces.
• Studies ( Wilder-Smith and Cobb) have also shown that there is
a significant rise in the intrapulpal and root surface
temperature and root surface alteration which is unfavourable
for fibroblast attachment.
• Liu et al. (1997), Showed no additional benefit when laser
treatment was used secondary to traditional SRP therapy. 61

62. Er:YAG
• After Er:YAG laser scaling on the on root surfaces in
vivo studies showed the bactericidal potential,
removal of lipopolysaccharide, reduction of endotoxin
and bacteria (Ishikawa, 1996)
• A rise of 1.4 degree intra-pulpal temperature is
observed.
62

63. • Research conducted on lasers so far has indicated the safety
and effectiveness of clinical application of Er:YAG laser for root
surface debridement than CO2 and Nd:YAG laser. (DCNA 2005)
63

64. ENAMEL MATRIX PROTEIN (EMP)
• It is based on the biologic concept that the application of Enamel
Matrix Protein (amelogenins) may promote periodontal regeneration
as it mimics events that take place during the development of
periodontal tissues.
• Clinical trials conducted for the assessment of the effectiveness of
Enamel Matrix Protein regarding its ability to improve periodontal
health.
• The results were better, as shown by a gain in the clinical
attachment level, probing depth reduction and restoration of bone
64

65. • In vivo and in vitro studies clearly indicate a greater potential
for cell and fiber attachment to demineralized root surfaces but
Evidence till date suggests that the use of root conditioning
agents to modify the root surface provides no benefit of clinical
significance for regeneration in patients with chronic
periodontitis.
65

66. BONE GRAFT
• Bone grafts- Bone grafts are the materials used for replacement
or augmentation of the bone.
• Grafting- Procedure used to replace / restore missing bone or
gum tissue.
Rationale
• Enhance regenerative capacity of bone
• Achieve new attachment apparatus
66

67. 67

68. 68

69. 69

70. A critical aspect of
periodontal regeneration
is the stimulation of a
series of events and
cascades at some point,
which can result in the
coordination and
completion of integrated
tissue formation.
70

71. 71

72. IDEAL CHARACTERISTIC OF BONE GRAFT
• Nontoxic
• Non-antigenic
• Resistant to infection
• Stimulates new attachment
• No root resorption or ankylosis
• Strong and resilient
• Easily adaptable
• Readily and sufficiently available
• Minimal surgical procedure 72

73. TYPES OF GRAFTS
• Osteogenic (Osteoproliferative)
Osteoconductive
Osteoinductive
73

74. Osteogenic
• Bone grafts capable of forming bone through osteoblastic cells
contained in the transplanted graft
• The process of bone formation, which begins with either
osteoblasts in the patient's natural bone or from surviving cells
in the bone graft that is placed.
• Osteoblasts forms new centers of ossification within the graft.
• Ex: autografts,
74

75. Osteoconduction
• The Graft material acts as a passive matrix like a scaffolding for new
bone to cover over itself.
• Process also known as Trell's effect
• Occurs with the ingrowth of capillaries in the new connective tissue.
• A material is osteoconductive when its structure & its chemical
composition facilitate new bone formation from existing bone.
• Ex: FDBA
75

76. Osteoinduction
• Process by which graft material is capable of promoting
osteogenesis, cementogenesis, new PDL formation.
76

77. AUTOGRAFTS
• First bone grafts reported for periodontal applications
(1923,Hegedius)
• Ideal graft material in bone reconstructive surgeries.
• Rich source of bone & marrow cells
• osteogenic potential
Extraoral
1. Illiac crest
2. Ribs
3. cranium
4. Tibial metaphysis
Intraoral
1. Extraction site
2. Maxillary tuberosity
3. Osseous coagulum
77

78. Cortical grafts-
• Less osteogenic potential,
• resorb faster
• For survival of osteocytes- vasucular supply within 0.1 mm
• Davis et al (2000) cortical bone grafts lacking vascular and
cellular pools on endosteal and periosteal surface may not be
able to sustain cellular viability.
78

79. Cancellous bone graft-
• Hematopoietic marrow, better osteogenic potential
• Have greater likelihood of supporting cell survival - Possibility
of diffusion of nutrients and revascularization from recepient
bed
79

80. EXTRAORAL SITES
Hip Marrow Grafts (illiac crest marrow)
• Highest regenerative potential-
Hiatt and Schallhorn ( 1971) clinical predictability of iliac autografts than
with intra-oral cancellous autografts.
Advantage
• excellent results in 2 & 3wall intra-osseous defects
• Disadvantage
• Ankylosis & Root resorption.
• possibility of surgical complications
• pain associated with donor site 80

81. INTRAORAL SITES
Significant gains in probing attachment level in treating one, two,
or three-wall (or combination) defects
Instruments Used
• Bone trap collecting osseous coagulum
• Maxillon bone retrieval device collection of bone shavings
81

82. Bone trephined
from within the
jaw
Post Extraction
sites (8-12weeks)
Bone removed
during osteoplasty
and ostectomy
Tori or exostosis Edentulous ridge
Maxillary
tuberosity
Retromolar areas
82

83. INSTRUMENTS
Bone trap
83

84. MAXILLON BONE RETEROVEAL
DEVICE
84

85. 85

86. CORTICAL BONE
• Shavings of cortical bone removed by hand chisel during
osteoplasty and ostectomy were used to treat one, two wall
defects.
• Large Particle size.
• Potential for sequestration
86

87. OSSEOUS COAGULUM
ROBINSON (1969)
• Use mixture of bone shaving & blood from surgical field.
• Concept based on that bone mineralized substances can induce
osteogenesis
• Smaller the particle size of the donor bone, the more its resorption
and replacement with host bone (additional surface area for the
interaction of cellular and vascular elements.)
• Sites - Exostoses, Tori, Heavy marginal ridges & Adjacent sites
undergoing osseous correction.
• Obtained with high- or low-speed ( 5000-30,000 rpm) burs during
osteoplasty 87

88. Disadvantage
• inability to aspirate during the collection process
• unknown quantity & quality of collected bone fragments
• Fluidity of the material
88

89. BONE BLEND
• The bone blend technique uses an autoclaved plastic capsule
and pestle.
• Bone is removed from a predetermined site, triturated in the
capsule to a workable, plastic-like mass, and packed into bony
defects
• Resultant particle size 210X105 micron m
89

90. BONE SWAGING
• This technique requires an edentulous area adjacent to the
defect, from which the bone is pushed into contact with the
root surface without fracturing the bone at its base.
• Bone swaging is technically difficult, and its usefulness is
limited
90

91. • Except furcation and crestal bone defects, intra- oral grafts are
comparable to iliac grafts.
• Autogenous bone grafts yield regenerative response superior to
those obtained using surgical debridement alone.
91

92. ALLOGRAFT
• Bone grafts harvested from one person for transplantation in
another.
• Used in periodontal therapy since last 3 decades.
• Problems associated with autogenous bone
- morbidity accompanying a second surgical site
- need for a sufficient quantity of material to fill multiple
defects
92

93. SOURCE
• Fresh frozen bone
• Demineralized freeze-dried bone allografts
• Freeze-dried bone allografts (FDBAs)/ autogenuous bone grafts
(ABGs)
93

94. AAP (1994)
• Cortical bone is recommended for use as allografts as it is less
antigenic and ti has more bone matrix and more inductive
components.
94

95. Steps in processing (Brunsvold & Mellonig)
• Cortical bone is harvested in a sterile manner. Long bones are the
source.
• The cortical bone is roughly cut to a particle size ranging from 500
µm to 5mm
• graft material immersed in 100% ethyl alcohol or a similar solvent 1
hour to remove fat that may inhibit osteogenesis.
• cortical bone is ground and sieved to a particle size range of
approximately 250 to 750 µm.
• Decalcification with 0.6 or 0.5 N HCl removes calcium, leaves bone
matrix, & exposes bone-inductive proteins
• Bone is washed in a sodium phosphate buffer to remove residual
95

96. • Cortical bone is frozen at -80°C for 1 to 2 weeks to interrupt
the degradation process
• Results from bacterial cultures, serologic tests, & Ag Ab assays
are analyzed. If contamination is found, the bone is discarded
or sterilized by additional methods
• Freeze-drying removes more than 95% of the water content
from the bone. It preserves three major specimen
characteristics;
• size,
• solubility, and
• chemical integrity.
• Freeze-drying destroys all cells & graft is rendered non-viable 96

97. Advantages
• Material is available in large quantities
• No donor site within the patient
• Reduces antigenicity
• Facilitates long-term storage
• Vacuum sealing in glass containers protects against
contamination and degradation of the graft material while
permitting storage at room temperature for an indefinite
period of time.
97

98. Disadvantage
• Process of preparing the graft material’s integrity & osteogenic
potential, & immunological response to it may diminish its
incorporation into the recipient bone
• A major concern is potential for disease transfer, particularly
viral transmission more particularly HIV
98

99. FDBA
• Introduced to periodontal therapy in 1976
• Osteoconductive
• Although FDBA contains inductive proteins, the polypeptides are
sequestered by calcium.
• This material is resorbed and replaced by host bone very slowly.
• Only graft material that has undergone extensive field testing for
the treatment of adult periodontitis.
99

100. • Mellonig, Bowers, and co-workers - reported bone fill
exceeding 50% in 67% of the defects grafted with FDBA and in
78% of the defects grafted with FDBA plus autogenous bone.
• FDBA-------- osteoconductive material
• DFDBA-------osteoinductive graft.
100

101. Freeze dried grafts +Antibiotics
• Terranova V et al. ----Addition of tetracycline theoretically
enhance its osteogenic potential.
• The addition of the antibiotic appears to enhance fibroblast
chemotaxis, be anti-collagenolytic, & produce a zone of
antibacterial activity during the critical stages of wound healing.
• Yukna R 1982 FDBA + tetracycline in a 4:1 volume ratio has shown
promise in t/t of osseous defects associated with localized juvenile
periodontitis.
• Significantly greater bone fill and defect resolution have been
shown with the FDBA and tetracycline composite than with the
allograft alone or the non-grafted control. 101

102. FDBA + AUTOGENOUS BONE
• Sanders et al 1983 found that more than 50% bone fill was
achieved in 80% of test cases grafted with FDBA + autogenous
bone but in only 63% of controls grafted with FDBA alone.
• Mellonig 1990 DFDBA has a higher osteogenic potential &
provides more bone fill than FDBA.
• FDBA is still used today, but a large-scale research review
showed that FDBA mixed with autogenous bone is more effective
at increasing bone fill than FDBA alone by Mellonig 1991.
102

103. DFDBA
• Synonymous –
• allogeneic, autolyzed, antigen-extracted (AAA) bone,
• demineralized bone powder,
• demineralized bone matrix, and
• demineralized bone matrix gelatin with decalcified freeze-dried
bone.
• Demineralization of allografts was performed because
the bone mineral blocked the effect of the factors
stimulating bone growth sequestered in bone matrix
including BMP.
103

104. • Experiments by Urist and co-workers have established the
osteogenic potential of DFDBA. Demineralization in cold,
diluted hydrochloric acid exposes the components of bone
matrix, closely associated with collagen fibrils, that have been
termed bone morphogenetic protein.
104

105. • BMP are a group of acidic polypeptides belonging to the
transforming growth factor-β gene super-family. They stimulate
bone formation through osteoinduction by inducing
pleuripotential stem cells to differentiate into osteoblasts
• Experimental animal studies have shown that demineralized
freeze-dried bone allograft has osteogenic potential
1. The bioactivity appears to be age dependent.
Younger animals ≥ older animals
105

106. • Bowers & associates, in a histologic study in humans, showed
new attachment and periodontal regeneration in defects
grafted with DFDBA.
• Mellonig & associates tested DFDBA against autogenous
materials in the calvaria of guinea pigs and showed it to have
similar osteogenic potential.
• These studies provided strong evidence that DFDBA in
periodontal defects results in significant probing depth
reduction, attachment level gain, and osseous regeneration 106

107. FACTORS AFFECTING
• Delaying the procurement of donor bone after death, improper
storage conditions, or other processing factors may play a
significant role in the bioactivity of the final DFDBA preparation
that makes its way to the clinician's office
• Age, gender, and medical status of deceased donors may also
affect osteogenic activity in the grafts taken from them.
• The inductive activity gradually decreases& eventually is reduced to
0 within a period of 1 5 days when decalcification with 0.6 N HCI is
performed at 2 5 °C, whereas in the cold ( 2 °C) the inductive
activity is fairly maintained even at 30 days (Urist & Dowell, 1 9
68).
107

108. • Ethyl or isopropyl alcohols in 0.6 N HCI produce total
inactivation of inductive substrate.
• Heating above 60 °C inhibits bone formation
108

109. CONCERN
• Potential for disease transfer, particularly viral transmission,&
particularly HIV.
• Mere freezing of bone allografts reduces the risk of disease
transfer to 1 in 8 million
• Russo et al The probability of HIV transfer following
appropriate DFDBA preparation has been calculated to be 1 in
2.8 billion
• 109

110. 110

111. XENOGRAFT
• Graft taken from another species.
• Naturally derived deproteinized cancellous bone from another
species (such as bovine or porcine or equine bone).
• Prepared by chemical or low-heat extraction of the organic
component from the bovine bone therefore aka inorganic bone.
• Osteoconductive
• Nielsen et. (1981) treated intrabony defects with Kielbone® (i.e.
defatted and deproteinized ox bone) and intraoral autogenous
bone grafts. The results, which were evaluated by periodontal
probing and radiographically, showed no difference between the
amount of clinical gain of attachment and bone fill obtained in
the two categories of defect.
111

112. Advantages
1. Unlimited supply
2. Safe
3. Biocompatible
4. Possesses the same structure as bone:
a. Compact appetite crystalline structure
b. Large inner surface area
c. Porosity similar to that of human cancellous bone
5. Permits physiologic vascular ingrowth
6. Permits complete integration and incorporation into bone
Disadvantage
• Bovine-derived grafts can cause disease transmission, which was
evident in the case of bovine spongiform.
112

113. BOVINE DERIVED BONE GRAFTS
• act as an Osteoconductive scaffold due to their porosity
• Provide structural components similar to that of human bone.
• Currently available graft are de-proteinated
113

114. BIO-OSS
• Bovine derived bone grafting material.
• The low-heat (300°C) extraction process removes all of the
organic components while maintaining the exact porosity, size
and trabecular architecture of bone.
• Available in cancellous and cortical granules , with partilcle size
100 X 200X 500 Å
114

115. BIO-OSS COLLAGEN
• It contains both-
• inoraganic ( Bio-oss granules 0.25-1 mm) and
• Organic ( 10% highly purified porcine collagen)
• This improves the handling characteristics- as graft particles
are adhered to each other.
115

116. OSSEOGRAFT®
• Demineralized bone derived type 1 collagen.
• It is prepared from bovine cortical bone.
• Non-immunogenic
• Flowable particles of approximately 250 µm that are completely
replaced by host bone in 4–24 weeks.
116

117. OSTEO-BIOL
• Xenograft of porcine origin.
• Heterogenous cortico-cancellous collagenated bone mix.
• Must be hydrated before use- with saline or patient’s blood to
enhance its adhesivity.
117

118. CORALLINE CALCIUM CARBONATE
Holmes 1979, Guillemin et al. 1987 proposed the use of coral
skeleton as a bone graft substitute.
Depending on the pre-treatment procedure, the natural coral
turns into-
1. non-resorbable porous calcium carbonate
2. Resorbable calcium carbonate
118

119. CORALLINE CALCIUM CARBONATE
• Kenney et al. 1985, Krejci et al. 1987, Yukna 1994, Mora &
Ouhayoun 1995, Yukna & Yukna 1998
• Implantation of coralline porous hydroxyapatite in intrabony
periodontal defects in humans produced more probing pocket
depth reduction, clinical attachment gain and defect fill than
non-grafting.
119

120. ALLOPLASTIC - BONE GRAFT SUBSTITUTE
• The 1996 World Workshop in Periodontics concluded
“synthetic graft materials function primarily as defect fillers”
• AAP 2003 & Position paper 2005 Synthetic graft materials
function predominantly as biologic space fillers.
120

121. • There are four kinds of alloplastic materials, which are
frequently used in regenerative periodontal surgery:
• Hydroxyapatite (HA),
• beta tricalcium phosphate,
• Polymers, and
• Bio-active glasses ( bio-glasses).
Advantages
• Absence of antigenicity
• No potential for disease transmission
• Unlimited supply
121

122. CERAMIC-BASED BONE GRAFTS
• Widely used
• Function primarily through osteo-conduction
• Have also been considered osteo-integrative, because of the
tenacious, intimate bond formed between the new mineralized
tissue & graft material
• Ceramics
• Calcium sulfate
• Calcium phosphates ( TCP & Hydroxyapatite),
• Bioactive glass 122

123. CALCIUM SULFATE
• Calcium sulfate or plaster of Paris was used for fracture treatment
by the Arabs in the 10th century, who would surround the
affected limb in a tub of plaster.
• In 1852 a Dutch army surgeon named Mathysen incorporated
plaster into the bandageable form which we are familiar with
today
• Medical grade calcium sulfate impregnated with tobramycin is
commercially available (Osteoset)
• It act as Osteoconductive matrix for the ingrowth of blood vessels
and associated fibrogenic and osteogenic cells.
123

124. • Reabsorbed by a process of dissolution, over a period of 5–7
weeks.
• When it set its compressive strength greater than cancellous
bone and a tensile strength slightly less than cancellous bone.
• Requires a dry environment to set and if it is re-exposed to
moisture it tends to soften & fragment. For this reason it has
no reliable mechanical properties in vivo and its application is
limited.
124

125. CALCIUM PHOSPHATES
Tri-calcium phosphate
• Porous form of calcium phosphate
• most commonly used β -tricalcium phosphate
• Biological filler which is partially resorbable & allows bone
replacement
• α & β TCP produced similarly, display different resorption
properties.
125

126. α TCP
• Monoclinic
• Less stable than β form
• Stiffer material
• Formed by heating β form above1180 °C
126

127. β TCP
• Rhombohedral
• More stable
• beta TCP has a compressive strength & tensile
strength similar to that of cancellous bone.
• It undergoes resorption over a 6–18 month period.
• The replacement of beta TCP by bone does not
occur in an equitable way. There is always less bone
volume produced than the volume of the graft
material resorbed.
127

128. • TCP as a bone substitute has gained clinical acceptance, but
results are not always predictable.
• Amler MH- TCP particles generally become encapsulated by
fibrous connective tissue & do not stimulate bone growth.
• In direct comparison with allogeneic cancellous grafts,
allogeneic grafts appear to outperform TCP.
128

129. SORBONE
• Pure beta TCP
129

130. Biphasic calcium phosphate
• Combination of the two primary forms of calcium phosphate
• A histological study- Hashimoto-Uoshima et al.(1995) biphasic
calcium phosphate supported active bone replacement from
surrounding bone which may have been triggered by macrophages.
• However, further studies are needed before clinical acceptance
130

131. INJECTABLE CALCIUM PHOSPHATE CEMENT
• Injectable, fast setting bioabsorbable
• Has high compressive strength
• In vivo- Osteoconductive carbonated appatite
• Chemical & physical characteristic similar to mineral stage of
bone
• Gradually replaced by natural bone
• Thirty subjects (mean age, 53.4 ± 9.1 years) with periodontitis
and narrow intrabony defects were enrolled in the study.
• This study failed to demonstrate any superior clinical outcomes
for the CPC group compared to the OFD group
131

132. HYDROXYAPATITE
• The primary mineral component of bone.
• Depending on the temperature preparation- Resorbable & non-
resorbable
• High-temperature preparation (sintering) of hydroxyapatite results in a
nonresorbable, nonporous, dense material.
• Low temperature resorbable, porous, no ceramic 132

133. • Dense hydroxyapatite grafts.
• Osteophillic , osteoconductive.
• Act primarily as inert biocompatible fillers.
• Studies -clinical defect fill greater than flap debridement alone
in the treatment of intrabony defects.
• Histologically, new attachment is not achieved.
133

134. Porous hydroxyapatite
• Obtained by the hydrothermal conversion of CaCO3
exoskeleton of the natural coral into the calcium phosphate
hydroxyapatite
• Pore size of 190 to 200 µm
• Which allows bone ingrowth into the pores & ultimately
within the lesion itself.
134

135. • Clinical defect fill, probing depth reduction, and attachment
gain have been reported.
• Kenney et al. provided histological evidence suggesting that
porous hydroxyapatite supports bone formation, but since no
evidence of a new CT attachment or cementum was noted, it
should be considered a biocompatible filling material.
135

136. BIOACTIVE GLASSES
• Composed of CaO, Na2O, SiO, P205
• Bond to bone through the development of a surface layer of
carbonated hydroxyapatite
• When exposed to tissue fluids in vivo, the bioactive glass is
covered by a double layer composed of silica gel and a calcium
phosphorus-rich (apatite) layer.
136

137. PERIOGLASS – OSTEOCONDUCTIVE
• Particle size - 90 to 710 μm,
• Fetner AE 1994 --In surgically created defects in nonhuman
primate, 68% defect repair was achieved when measuring new
attachment
• Compared with TCP, HA, & unimplanted controls, & PerioGlas to
produce significantly greater osseous and cementum repair.
• It also retard epithelial downgrowth, which may be responsible
for its enhanced cementum and bone repair.
137

138. BIOGRAN
• Particle size - 300 to 355 μm
• Formation of hollow calcium phosphate growth chambers occurs with
this particle size because phagocytosing cells can penetrate the outer
silica gel layer by means of small cracks in the calcium phosphorus
layer and partially resorb the gel.
• leads to formation of protective pouches where osteoprogenitor cells
can adhere, differentiate, & proliferate.
• According to the manufacturers, larger particles do not resorb in the
same manner, which slows the healing process theoretically because
bone healing must progress from the bony walls of the defect and
smaller particles cause a transient inflammatory response, which
retards the stimulation of osteoprogenitor cells.
• Optimal particle size 100-300 micron.
138

139. POLYMERS
• Natural
• Polysaccharides (eg, agarose, alginate, hyaluronic acid, chitosan)
• polypeptides (eg collagen, gelatin)
• Synthetic
• Synthetic polymers (eg, poly(glycolic acid), poly(L-lactic acid),
polyorthoester, polyanhydride)
• Polymers are more widely used as barrier materials in GTR
procedures for t/t of periodontal defects.
• At present, several polymer systems are being used for bone &
periodontal regeneration
• Polylactic acid (PLA)-based polymers
139

140. Copolymers
• These polymers have proved to be effective in periodontal
applications as barrier materials
• Biocompatible microporous polymer containing PMMA, PHEMA,
& calcium hydroxide is available
• hydrophilic and Osteophilic
• Histologic evaluations revealed that the polymer was associated
with minimal inflammation & infrequent foreign body giant
cells, with evidence of both bone apposition & soft tissue
encapsulation, at 1 to 30 months following implantation
140

141. HTR (BIOPLANT)
• Non-resorbable biocompatible microporous composite of PMMA,
PHEMA & calcium hydroxide.
• Favorable clinical results have been achieved with HTR for
treatment of infrabony & furcation defects.
• Improved clinical results with this synthetic substitute have not
always been achieved.
• Shahmiri et al 1992 -----no clinical improvement in probing
depth, most reports have supported the use of HTR as a bone
substitute. 141

142. NANO-CRYSTALLINE HYDROXY APPATITE
• 65% water and 35% nan structured.
• Introduced for augmentation procedure in osseous defect
Advantage
• Close contact with surrounding tissue
• Quick resorption and Large no. of molecule on the surface
142

143. BONE GRAFT TECHNIQUE
1. Remove all etiologic factors
2. Stabilize teeth if necessary
3. Flap design with a plan for closure
4. Degranulation of defect and flap
5. Root preparation.
6. Encourage a bleeding bony surface
7. Pre-suturing
8. Condense graft materials well
9. Fill to a realistic level
10. Good tissue coverage
11. Periodontal dressing
12. Antibiotic coverage 143

144. Flap design
• Conventional flap and papilla preservation flap.
• scalloped incisions with full gingival preservation are necessary to
be able to completely close the site at the completion of surgery.
• Full thickness flaps, reflected beyond the mucogingival junction,
are recommended.
• Vertical releasing incisions should be used as necessary for proper
access to the defect
144

145. Degranulation of defect and flap
• All granulomatous soft tissues should be removed from the
bony walls of the defect and the associated tooth surfaces.
• The inner aspect of the flap should be checked for tissue tags
& epithelial remnants, which should also be removed
145

146. Root preparation
• It is essential that all calculus, bacterial plaque, other soft debris
& altered cementum be removed from the involved root
surfaces.
• Ultrasonic and hand instruments as well as finishing burs are
useful for this purpose.
• This aspect of therapy is the most tedious, difficult & time-
consuming but the most essential aspect.
• There is some suggestion that the use of chemicals such as
citric acid or tetracycline paste may be an aid in root
detoxification & in making the root surface more biologically
acceptable for healing. 146

147. Encourage a bleeding bony surface
• Generally already accomplished by proper defect debridement.
• However, if the defect walls are relatively dry and/or
glistening, healing may be enhanced by intra-marrow
penetration to encourage bleeding and allow the ingress of
reparative cells, vessels and other tissues.
• Such penetrations can be accomplished with a small round bur
or hand instruments.
147

148. Pre-suturing
• Loose placement of sutures, left untied, prior to the filling of
the defect reduces the possibility of displacing the graft
material during the suturing process.
• It also simplifies the last steps of the procedure, in that once
defect fill has been completed, the already placed sutures need
only to be tied to complete the surgical procedure
148

149. Condense graft material well
• The graft material should be placed in small increments
• sterile plastic or Teflon-lined amalgam carriers place the
material and sterile amalgam squeeze
• cloths to use over the suction tip to dry the defect without
removing any of the graft material
• Process is repeated until the defect is filled
149

150. Fill to a realistic level
• Defects should be filled with the synthetic graft materials only
to the level of the defect walls, There is little suggestion that
overfilling with these materials results in supracrestal bone
formation.
• Overfilling may actually be counterproductive in that it may
preclude proper flap closure, thereby retarding healing
150

151. 151

152. Good tissue coverage
• If flap design has been good, primary closure with replaced
flaps and contact of the interproximal papillae can usually be
obtained .
• If tissue coverage of the alloplastic graft material is not
satisfactory, additional releasing incisions or reflection may be
necessary.
152

153. • Periodontal dressing
• The use of a firm, protective periodontal dressing for 10 days
following bone replacement graft surgery is suggested.
It has become popular not to use dressing for many periodontal
surgical procedures, but prudence would seem to suggest that
the possible impingement of foreign materials into the graft site,
flap displacement and loss of graft material that would
jeopardize the success of treatment make the use of protective
dressings preferable.
153

154. Antibiotic coverage
• Tetracycline-type drugs are the antibiotics of choice for
immediate postsurgical plaque suppression due to their broad
spectrum of activity, attraction to healing wound sites and
concentration in GCF.
• They are administered in therapeutic doses for the first 10
days following surgery or until the patient can practice proper
plaque control in the area
154

155. Postsurgical care
• If the dressing and sutures are removed prior to 10 days,
another dressing is often indicated. When the first
postoperative treatment is at 10 or more days following
surgery, additional dressings are rarely indicated
• The patient is started immediately on gentle but thorough
plaque-control methods, including the use of antibacterial
rinses.
155

156. Schedule for professional plaque control in the office as follows:
• every 10 days for 3 visits;
• every month for 2 visits; and
• every 3 months
• The grafted areas should not be probed prior to 3 months
postsurgically
• Radiographs taken prior to 6 months provide uncertain
information.
156

157. HEALING
• First wound-healing phase is revascularization.
• initiated within the first few days following the grafting
procedure. Blood vessels originating from the host bone invade
the graft.
• A pore size of 100 to 200 µm is very conducive to vascular
invasion.
• incorporation of the grafted bone particles by new bone
emanating from the host.
• If the graft material contains vital osteogenic precursor cells
that survive the transplantation process, these cells may
contribute to new bone formation.
157

158. • The graft may possess inductive proteins that actively stimulate
the host to form new bone, or the graft may simply act
passively as a lattice network over which the new host bone
forms
• Creeping substitution - As the graft is being incorporated, it is
gradually resorbed and replaced by new host bone.
• The final phase of healing is bone remodeling.
• Resorption, replacement , and remodeling take many years.
158

159. FATE OF BONE GRAFT
• Once the material is placed in the bony defect it may act in a
number of ways which may decide the fate of the graft
material.
• The various possibilities include:
Bone graft material may have no effect at all.
The bone graft material may act as a scaffolding material for the host site
to lay new bone.
The bone graft material may itself deposit new bone because of its own
viability. 159

160. • Bioresorbable
• Bioabsorbable
160

161. FACTORS AFFECTING THE SUCCESS OR
FAILURE OF REGENERATION PROCEDURES
1. Plaque control
2. Underlying system disease (eg, diabetes)
3. Root preparation
4. Adequate wound closure
5. Complete soft tissue approximation
6. Periodontal maintenance, short and long term
7. Traumatic injury to teeth and tissues
8. Defect morphology Type of graft material
9. Patient’s repair potential
Mellonig (1992)
161