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Year Three Periodontology
#7
Elio Reyes, D.D.S.,M.S.D.
Reconstructive Periodontal Surgery
Furcation Management
Chapter 67
Repair or Regeneration?
Repair Healing of a wound tissue that does not fully restore the
architecture or function of the part.
May see new gingival connective tissues and possibly new
bone
Critical factor is how these tissues connect to the root surface.
In repair there is no development of new cementum and no development of a new
PDL. It is only a partial restoration of the supporting periodontal tissues
The newly regenerated gingival connective tissues and
possible new bone attach to the root via a long junctional
epithelium or connective tissue adaptation.
Periodontal wound healing
Epithelium
Gingival connective tissue
Alveolar bone
Periodontal ligament
Karring T, Nyman S, Lindhe J:J Clin Periodontol 1980; 7:394
Karring T, Nyman S, Lindhe J:J Clin Periodontol 1984; 11:41
Repair or Regeneration?
Regeneration is defined as a reproduction or
reconstitution of a lost or injured part.
Regenerated tissues attach to the root surface in a
similar manner to the original attachment. Thus, after
healing is complete, connective tissue attaches to the
root via a new PDL which engages fibers emerging from
the root surface which is covered by new cementum.
When needed, new bone also forms in the appropriate
location.
Need to remove the junctional and sulcular epithelium
for regeneration.
A
B
Repair and Regeneration. The arrow indicates the most apical part of the
junctional epithelium. A, Repair, healing by long junctional epithelium. Note
that some bone is new but the PDL is not. B. Regeneration, new alveolar
bone, new PDL, new cementum.
regeneration
long junctional epithelium
Points to remember
The probing depth is reduced by
resolution of the inflammation
and subsequently the probe does
not penetrate as deeply.
This is not new attachment
New connective tissue fibers
will not attach to the root
surface if epithelium is
present.
PDL provides the cells
needed for regeneration.
Probe penetrates past
the junctional epithelium
because of inflamed tissue
Less probe
penetration with
resolution of the
Inflammation.
Epithelium Control
Delay epithelial migration
Coronal displacement of the flap
Epithelial exclusion
Guided tissue regeneration
Cells from the pdl have the potential for
regeneration
Figure 42-3 Sources of regenerating cells in the healing stages of a
periodontal pocket. Left, Intrabony pocket. Right, After therapy the clot
formed is invaded by cells from A, the marginal epithelium; B, the gingival
connective tissue; C, the bone marrow; and D, the periodontal ligament.
Epithelium Control
Clot stabilization
Undisturbed and stable maturation of the clot
usually prevents apical migration of the
epithelium
Coronally positioned flaps place the wound
margin away from the critical healing site
Space maintenance
Important in guided tissue regeneration
Keep membrane from collapsing into the
defect
Use titanium reinforced membranes
Tissue Healing Responses
•Epithelium
•Connective Tissue
•Bone
•Periodontal Ligament
Guided Tissue Regeneration
GTR consists of placing barriers of different types to cover the
bone and periodontal ligament, thus temporarily separating
them from the gingival epithelium.
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 cells from the
periodontal ligament and the bone.
Membranes classification
Resorbable
Non-resorbable
Membranes classification
Non-resorbable membranes
First membranes used
Require a second surgical procedure
Most extensive evaluated membranes
Gold standard
Membranes classification
Non-resorbable membranes
Nucleopore and Millipore filters
Ultrathin semipermeable silicon barriers
Rubber dam
ePTFE
dPTFE (non porous)
Melcher,AH: J Periodontol 1976;47: 256
Aukhil I: J Periodontol 1986; 57:727
Salama H: Int J Periodont Restor Dent 1994;14:16
Guided Tissue Regeneration
(GTR)
Non-resorable membranes
Needs additional surgical procedure to remove membrane
Example: Gore-Tex® polytetrafluoroethylene
(e-PTFE)
Figure 67-9 Different shapes and sizes of expanded polytetrafluoroethylene
membranes marketed by Gore-Tex (Flagstaff, Ariz).
Membrane –blocks epithelium and the
gingival connective tissue;
allows nutrients to pass;
titanium reinforced if needed.
Healing from bone and PDL
ePTFE
Gore-Tex. Transgingival microstructure
Partially occlusive portion
Open microstructure portion
For applications involving
a structure, such as a tooth,
that extends trough the gingiva
into the oral environment
Product Information 2003: WL Gore & Associates, Inc.
ePTFE Titanium reinforced
Titanium struts incorporated between two
sheets of ePTFE
Same characteristics of ePTFE
Added shapeability and space making
Product Information 2003: WL Gore & Associates, Inc.
Guided Tissue Regeneration
(GTR)
 Resorbable membranes
Bioabsorbable or biodegradable
 Polylactid acid, Polyglycolic acid
Examples:
 Vycril® Polyglactin 910
 Resolut®, Resolut XT® PGA-PLA
 Good handling characteristics, remains intact for 8 to 10
or 16 to 24 weeks then gradually resorbs.
 Collagen membranes. Perdominantly type I collagen
Examples:
 Biomend, Biomend extent, Ace.
 Excellent handling, biodegrades in 16 or more weeks.
Collagen membranes
Initially used as gel or matrix to fill or cover periodontal
defects
Various collagen subtypes: Predominantly type I
Derived from different animal sources: bovine,
porcine; tendon, dermis
Laurell L, Gottlow J: Int Dent J 1998;48
Wang HL:Dent Clin North Am 1998; 42:3
Resolut XT
3-layer structure
Occlusive copolimer of PLA and PGA 85:15
Porous structure with trimethylene carbonate
Cross section: 2 random fiber
matrices on gingival and defect
sides of a cell occlusive film
Surface with Trimetric pattern
Increases membrane flexibility
Product Information 2003: WL Gore & Associates, Inc.
Laurell L, Gottlow J: Int Dent J 1998;48
McClain and Schallhorn
Int. J. PERIO REST DENT 1993
5 Year results evaluating 76 sites in 32 patients
Guided Tissue Regeneration was significantly
enhanced by the addition of root conditioning
and grafting procedures
Used citric acid for root conditioning and
DFDBA
Sites treated showed good long term stability
Success of GTR
Machtei et al J. Perio 1994
Mandibular class two furcations
30 subjects with a one year surgical re-entry
Probing depth reduction of 2.6 mm
Horizontal probing attachment gain of 2.62 mm
Vertical gain of 0.95 mm
Pre-surgery SRp was not helpful
Better results in those subjects with greater initial
pocket depth, good oral hygiene, minimal
inflammation and sites that did not harbor AA
Root Preparation
Mechanical
Hand instruments
Sonics and Ultrasonics
Finishing burs
Chemical
Citric acid
Fibronectin
Tetracycline hydrochloride
EDTA 24%, ph neutral (PrefGel®)
For very tenacious calculus or in those
cases where the calculus and cementum
are indistinguishable, consider using a
high-speed rotary diamond or a diamond
– studded ultrasonic scaler.
Must have direct vision via flap
procedure.
During surgical root preparation, fine diamonds or finishing burs
produce the
smoothest root surface followed by manual and power-driven scalers.
Preparation of the Root Surface
Citric acid
pH 1 for 2-3 minutes
Produces a 4 μm (micron) deep demineralized
zone with exposed collagen fibers
Eliminates endotoxins and bacteria from the
tooth surface
Retards epithelium from migrating over treated
roots
Removes smear layer and widens orifices of
dentinal tubules
Preparation of the Root Surface
-2-
Fibronectin
A glycoprotein to help fibroblasts attach to root
surfaces
Tetracycline Hydrochloride
Paste made from a tetracycline capsule.
In addition to the effects noted for citric acid
also see an anti-collagenolytic or collagen
stabilizing effect plus a lingering antibacterial
effect
EDTA 24% ph neutral PrefGel®
Ethylene diamine tetra acetic acid
Manual Instrumentation
Finishing Burs
Ultrasonics
Chemical
Growth Factors
PDGF Platelet derived growth factor
IGF Insulin like growth factor
TGF Transforming growth factor alpha and
beta
Tissue engineering aims to enhance bone
grafts with growth factors
Growth Factors
Dr. Sam Lynch SIU/SDM
PDGF Platelet derived growth factor
Recombinant (rhPDGF) is supplied
with an inert filler (beta-tricalcium
phosphate) which is mixed before
insertion
Periodontal Regeneration
Adjunctive Agents
EMDOGAIN® Tissue Engineering.
 An enamel matrix protein (mainly amelogenin) derived from
developing tooth buds of fetal pigs (porcine).
Accelerate the growth of the pluripotential stem cells from
the PDL. The primitive cells from the PDL win the race to
close the wound with new cementum, PDL and bone
rather than epithelium.
Packaged in a syringe as a viscous gel that is applied to
the root surface.
Need to completely control bleeding before applying
this product
J.Perio 2000: Emdogain® produces a positive effect on
the osteoblast
Platelet Rich Plasma (PRP)
Developed from patient’s blood with a cell separator
Centrifugation of 55 ml of whole blood results in
approximately 10 ml of PRP which when mixed with
thrombin and calcium chloride results in the
degranulation of platelets and the subsequent
release of growth factors
Growth factors include PDGF TGFβ etc
PRP stimulates both hard and soft tissue maturation
and promotes healing
The ideal bone graft material
should
Be biocompatible
Completely biodegradable
Osteoconductive, osteoinductive, osteogenic
Inexpensive
Easy to handle
Able to support the defect area until bone
growth is complete
Types of grafting materials
Origin:
Autogenous: Autograft
Human Tissue: Allograft
Animal: Xenograft
Synthetic: Alloplast
Bone Grafts
Autografts
 Intraoral sites
Osseous coagulum
Obtained by using rotary instruments on intraoral bone
at the surgical site
Bone blend
Cortical or cancellous intraoral bone that is obtained
with a trephine, chisel or rongeur. It is placed in an
amalgam capsule and triturated into particle size in the
range of 100 to 200 microns.
Cancellous Bone Marrow. Maxillary tuberosity, healing
sockets (8 to 12 weeks) edentulous areas.
Bone swaging
Bone Swaging
Bone Grafts
Autografts
Extraoral sites
Iliac bone
Root resorption
Not practical to use
Allografts
Graft between genetically dissimilar members
of the same species
Freeze-Dried Bone
Particle size 250 to 750 μm
Mineralized or Demineralized
Hydrochloric acid demineralization exposes
the bone inductive proteins, collectively called
bone morphogenic proteins (BMP).
For periodontal defects DFDBA is utilized
because it is osteoinductive.
For ridge augmentation or extraction site
fill, the bone is not decalcified (FDBA)
resulting in a product that better retains its
form (osteoconductive).
Bone Grafts Terminology
Osteoconduction. A physical effect by which
the matrix of the graft forms a scaffold that
favors outside cells to penetrate the graft and
form new bone.
Osteoinduction. A chemical process by
which molecules contained in the graft (bone
morphogenic protein) convert the neighboring
cells into osteoblasts, which in turn form
bone.
Allografts (continued)
 Freeze-Dried Bone…
Ability to induce bone formation may vary with processing
Age of donor may play a factor
BMP varies from bone to bone bank.
Osteogenin or bone morphogenic protein 3
(BMP3) appears to enhance osseous regeneration
and is added to some bone grafting products.
AlloGro®. Donor tissue material bioassayed for
osteoinductive activity.
Inactive DFDBA can be made more effective by
adding recombinant human bone morphogenic protein
See better results when DFDBA is combined with
autogenous bone
Probability that DFDBA might contain HIV following
appropriate screening and processing procedures has
been calculated at 1 in 8 million.
Xenografts
Graft obtained from a member of one species and transplanted to a member
of another species.
Most common xenograft used today is organic bovine
bone.
PepGen P-15®
Combination of a cell-binding peptide (p-15) with
anorganic bovine-derived hydroxyapatite bone matrix.
P-15 is a synthetic clone of the 15 amino acid
sequence of Type 1 collagen that is uniquely involved
in the binding of cells, particularly fibroblasts and
osteoblasts.
PepGen P-15 Particulate
PepGen P-15 Putty
PepGen P Flow (syringe)
Alloplasts
Synthetic grafting materials
 Not a reliable substitute for autografts or allografts.
 Usually heals by fibrous encapsulation.
 Convenient, no significant osteoinductive capacity.
Examples:
 Calcium Sulfate. Plaster of Paris
Capset®
Plastic Materials
HTR® (hard tissue replacement)
Calcium coated polymer of Poly-methyl
methacrylate and hydroxy ethyl methacrylate
Calcium Phosphate: Hidroxyapatite, βTCP
Bioactive Glass: Perioglass
Calcium sulfate as a bone graft
 Oldest bone graft material. Not expensive, easily stored and
used.
 Properties of calcium sulfate
An effective barrier membrane
Maintains space for osteogenesis
Has angiogenic properties
Has a hemostatic function
Can deliver growth factors
Can be used in combination with other bone graft
materials
Often mixed with DFDBA
Is osteoconductive
Commercial brand is CAPSET® -- medical grade calcium
sulfate
Time release calcium sulfate undergoes controlled and uniform
degradation over a period of 16 weeks. BoneGen®
Alloplasts
-2-
 Calcium Phosphate
 Hydroxyapatite (HA) Ceramic nonporous
 Examples: Calcitite® Osteogen®
 Generally nonbioresorbable
 Tricalcium phosphate (TCP) Ceramic
nonporous
 Examples: Synthograft® and Peri-OSS®,
Carrier of Gem21®
 Partially bioresorbable
 Porous HA
 Example: Interpore®
Alloplasts
-3-
Bioactive Ceramic Glass
Example: (PerioGlass®)
Silicon dioxide 45%; sodium oxide
24.5%; calcium oxide 24.5%;
phosphorus pentoxde
When in contact with tissues attracts
osteoblasts
Non resorable?
Bone Grafts
 Evidence indicates that significant bone fill beyond
that of debridement controls can be expected
following the use of bone grafts.
 Mean defect fill averages approximately 60 to 65%
in a number of studies.
 Histologic evidence indicates some regeneration
occurs after the use of autogenous grafts, DFDBA,
and Xenografts.
 No confirmed regeneration using non-bone
products
Bone Grafts
New bone formation starts at 7 days
Cementogenesis at 21 days
New periodontal ligament at 3 months
Radiographic evidence of increasing bone
density often not seen until 6 months
Maturation of grafted material may take up to
2 years
Treatment of Infrabony Defects
after Edward S. Cohen -1
1. Full thickness mucoperiosteal flap using
sulcular incisions.
Conservation of interproximal tissue to
achieve primary closure.
Flap extended at least one tooth mesial
and distal to the defect.
Treatment of Infrabony Defects
after Edward S. Cohen -2
2. Removal of plaque, calculus, softened
cementum, and the junctional epithelium from
the root surface.
Ultrasonics, hand instruments, finishing
burs, smooth diamond stones are utilized.
Treatment of Infrabony Defects
after Edward S. Cohen -3
3. Removal of all granulation tissue and
residual fibers attached to the bone.
Fibers must be removed to open the marrow
spaces and permit intimate contact between graft
material and bone.
Use large curettes against the bony surface.
Missed any infrabony defects? Look for bleeding.
Treatment of Infrabony Defects
after Edward S. Cohen -4
4. Chemical root treatment?
Citric acid, tetracycline, PrefGel®.
5. Decortification
Small holes made in bone using curette or small
round bur.
Permits a rapid proliferation of granulation tissue
with undifferentiated mesenchymal cells thus see
a more rapid regeneration of bone and
anastomosis of graft and bone.
Treatment of Infrabony Defects
after Edward S. Cohen -5
6. Scrape the PDL with the tip of an explorer to
promote bleeding and stimulate cell proliferation.
7. Placement of the graft material and/or barrier
membrane.
8. Flaps are sutured for primary closure and
coronal positioning.
9. Postoperatively
Antibiotics in most cases. Analgesics. Chlorhexidine.
Ice. Recall q. 2 weeks, then monthly.
Six Years Later
Furcation Involvement
and Treatment.
Treatment of Furcation
Involvement
Vertical / Horizontal component
Concerns
Root trunk
Concavities
Degree of root separation
Enamel projections
Caries
Occlusion
Figure 68-1 Glickman's classification of furcation involvement. A, Grade I furcation involvement.
Although a space is visible at the entrance to the furcation, no horizontal component of the furcation
is evident on probing. B, Grade II furcation in a dried skull. Note both the horizontal and the vertical
component of this cul-de-sac. C, Grade III furcations on maxillary molars. Probing confirms that the
buccal furcation connects with the distal furcation of both these molars, yet the furcation is filled with
soft tissue. D, Grade IV furcation. The soft tissues have receded sufficiently to allow direct vision
into the furcation of this maxillary molar.
Different anatomic features that may be important in prognosis and
treatment of furcation involvement. A, Widely separated roots. B, Roots
are separated but close. C, Fused roots separated only in their apical
portion. D, Presence of enamel projection that may be conducive to early
furcation involvement.
is the horizontal component that distinguishes furcation involvement.
>3mm horizontal is a class two Hamp furcation involvement
Treatment options with furcation
invasion
Grade one furcation invasion
Resolve the pocket
Odontoplasty if narrow and inaccessible
Remove enamel projection if present
 Grade two furcation invasion
Regenerative procedures especially in mandibular molars
 Grade three furcation invasion
Open furcation for patient access (mandibular)
Root removal
Extraction
Maintain in a compromised state
Treatment options with furcation
invasion
 Grade one furcation invasion
 Resolve the pocket
 Odontoplasty in some cases
 Grade two furcation invasion
 Regenerative procedures especially in mandibular molars
 Tooth with a class two furcation has a guarded prognosis not a
poor prognosis
 Grade three furcation invasion
 Open furcation for patient access (mandibular)
 Root removal
 Extraction
 Maintain in a compromised state
Treatment options with furcation
invasion
 Grade one furcation invasion
Resolve the pocket
Odontoplasty in some cases
 Grade two furcation invasion
Regenerative procedures especially in mandibular molars
Grade three furcation invasion
Open furcation for patient access (mandibular)
Sometimes called a tunnel procedure
Root removal
Extraction Implant?
Maintain in a compromised state