Osseointegration/ orthodontic continuing education

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Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.

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GOOD MORNING

INDIAN DENTAL ACADEMY

Leader in continuing dental education www.indiandentalacademy.com

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Endosseous osseointegrated dental implantwww.indiandentalacademy.com

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“OSSEOINTEGRATION”

Guided by : Dr. Suresh Sajjan M.C www.indiandentalacademy.com

Contents :

Historical review

Development of concept of osseointegration

Definitions

Scope of osseointegration

Fibrointegration Vs Osseointegration

Ultra structure of osseointegration

Biology of Osseointegration

Mechanism of osseointegration

• Contact osteogenesis vs distant osteogenesis

• Osteoinduction vs osteoconduction www.indiandentalacademy.com

Anchorage mechanism or Bonding mechanism

• Biomechanical bonding

• Biochemical bonding

Key factors responsible for successful osseointegration

Success criteria of implants

Clinical evaluation of osseointegration

• Invasive methods

• Non invasive methods

Failure and loss of osseointegration

Conclusion

List of references www.indiandentalacademy.com

HISTORICAL REVIEW

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500 BC – Etruscan population

600 AD – Mayan population

“First evidence of use of implants”

1700 – John hunter “Transplantation”

Transmission of various diseases

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1809 Maggiolo

Gold roots

1939 – Strock

Vitallium screw

1948 – Goldberg and Gershkoff1943 – Dahl

Subperiosteal implantwww.indiandentalacademy.com

Consistent failures :

Inflammatory reaction

Gradual bone loss

Fibrous encapsulation

1960 – Linkow Blade vent implant

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“CONCEPT OF OSSEOINTEGRATION”

Dr. Per-Ingvar Branemark Orthopaedic surgeon

Professor University of Goteburg, Sweden.

Threaded implant design made up of pure titanium.www.indiandentalacademy.com

Integrated titanium fixture

1952 vital microscopic studies (Bone marrow of rabbit fibula)

“Osseointegration”

Repair of major mandibular and tibial defects.

Optical chamber

Clinical Study www.indiandentalacademy.com

Development of procedures for rehabilitation of edentulism :

Experimental study in dogs

First experimental study

Subperiosteal and Transosseous

Soft tissue reaction

Use of titanium fixtures

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Two stage procedure

Evidence for osseointegration

Macroscopic level

Histological level

Radiological level

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Intact bone to implant surface

Basic research 1952 to 1965 13-15 year extensive research

1965 First clinical evidence of implant insertion

“Edentulous human patient for resorbed edentulous ridge”

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Definitions :

“The apparent direct attachment or connection of osseous tissue to an inert, alloplastic material without intervening connective tissue”.

- GPT 8

Structurally oriented definition :

“Direct structural and functional connection between the ordered, living bone and the surface of a load carrying implants”.

- Branemarks and associates (1977)

Histologically :

Direct anchorage of an implant by the formation of bone directly on the surface of an implant without any intervening layer of fibrous tissue.

- Albrektson and Johnson (2001)www.indiandentalacademy.com

Clinically :

• Ankylosis of the implant bone interface.

Schroeder and colleagues 1976

“functional ankylosis”

• “It is a process where by clinically asymptomatic rigid fixation of alloplastic material is achieved and maintained in bone during functional loading”

- Zarb and T Albrektson 1991

Biomechanically oriented definition :

“Attachment resistant to shear as well as tensile forces”

- Steinmann et al (1986). www.indiandentalacademy.com

Scope of osseointegration in dentistry

1) Prosthetic rehabilitation of missing teeth

Complete edentulous maxilla and mandible rehabilitation.

Single tooth replacement Partial dental loss replacement

Removable prosthesis Fixed prosthesis

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2) Anchorage for the maxillofacial prosthesis

Auricular Prosthesis

Ocular Prosthesis www.indiandentalacademy.com

3) For rehabilitation of congenital and developmental defects

- Cleft palate

- Ectodermal dysplasia

Nasal prosthesis

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4) Complex maxillofacial defect rehabilitation

6) Orthodontic anchorage.

5) Distraction osteogenesis new bone formation

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AAID (1986) – “Defined fibrous integration as tissue to implant contact with interposition of healthy dense collagenous tissue between the implant and bone”.

“Direct bone to implant interface without any intervening layer of fibrous tissue”.

FIBROINTEGRATION

Vs

Concept of Bony Anchorage

Branemark (1969)

Concept of soft tissue anchorage

Linkow (1970), James (1975), Weiss (1986).

OSSEOINTEGRATION

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Fibrosseousintegration :

“Pseudoligament”, “Periimplant ligament”, “Periimplant membrane”.

Hypothesis – Collagen fibers function similar to the sharpeys fibers in the natural dentition.

Fact : The histological difference between the sharpeys fibers and collagen fibers around the implant.

Natural teeth Implant

Oblique and horizontal group of fibers

Parallel, irregular, complete encapsulation

Uniform distribution of load (Shock absorber)

Difficult to transmit the load

Failure : Inability to carry adequate loads Infection www.indiandentalacademy.com

Parallel fiber arrangement

Complete fiber encapsulation

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Fibrosseousintegration Osseointegration

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ULTRASTRUCTURE OF OSSEOINTEGRATION

Soft tissue interface

Cortical bone

Spongy bone

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Biology of Osseointegration (Branemark)

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Mechanism of osseointegration

Phase Timing Specific occurrence 1. Inflammatory

phase Day 1-10 Adsorption of plasma proteins

Platelet aggregation and activation Clotting cascade activation Cytokine release Nonspecific cellular inflammatory response Specific cellular inflmmatory response Macrophage mediated inflammation.

2. Proliferative phase

Day 3-42 Neovascularization Differentiation, Proliferation and activation of cells. Production of immature connective tissue matrix.

3. Maturation phase

After day 28

Remodeling of the immature bone matrix with coupled resorption and deposition of bone. Bone remodeling in response to implant loading Physiological bone recession. www.indiandentalacademy.com

Contact osteogenesis vs distant osteogenesis :

Osborn and Newesley (1980) : Proposed 2 different phenomena

Distant osteogenesis

Contact osteogenesis

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Contact OsteogenesisRelies on Migration of

Differentiating Osteogenic cell to Implant surface

Undifferentiated Perivascular connective cells

Differentiating Osteogenic cells

Osteoconduction :

Migration of differentiating osteogenic cells from the recipient host bed to implant surface where they attach and proliferate.

Fibrin

Smooth surface Rough surfacewww.indiandentalacademy.com

Osteoinduction :

Phenotypic conversion of undifferentiated mesenchymal cell osteoprogenitor cell Bone forming cell (Osteoblast & osteocyte)

Albrektsson and Johanson (2001) : The term osteoconduction and osteoinduction are inter related but not the identical phenomena that occurs during wound healing.

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Key factors responsible for successful osseointegration

Implant material

biocompatibility

Loading

conditions

Implant design

characteristic

Implant surface characteristic

State of the implantation or host bed

Surgical considerations

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IMPLANT MATERIAL

BIOCOMPATIBILITY

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Implant materials

Metals Ceramics Polymers

Chemical composition

Biological compatibility

Bio inert Bio tolerant Bio active

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Biological biocompatibility

Chemical composition Metals Ceramics Polymers

Biotolerant Gold Polyethylene

Cobalt-chromium alloys

Polyamide

Stainless steel Polymethylmethacrylate

Zirconium Polytetrafluoroethylene

Niobium Polyurethane

Tantalum

Bioinert Commercially pure titanium

Aluminum oxide

Titanium alloy (Ti-6Al-4V)

Zirconium oxide

Bioactive Bioactive Hydroxyapatite Hydroxyapatite

Tricalcium Tricalcium phosphate phosphate

Calcium Calcium pyrophosphate pyrophosphate

Fluorapatite Fluorapatite

Carbon:vitreous, Carbon:vitreous, pyrolytic pyrolytic

BioglassBioglass

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Metals :

Commercially pure titanium (CPTi) : 99.75%

Most biocompatible material excellent long term clinical function

Adherent, self repairable titanium dioxide (TiO2/ TiO) passivated layer.

(10A0 within seconds, 100A0 within a minute.)

Steinman (1988) referred this layer as Biologically inert

On Histological investigation intimate contact between the titanium surface and the periimplant bone.

(Branemark 1977, Albrektsson et al 1984)

Chemical purity, surface cleanliness Osseointegration www.indiandentalacademy.com

Titanium alloys : Ti6Al4V(90%Ti, 6% Al, 4% V)

Johonson (1992) - Cp titanium higher torque removal values than Ti6Al4V screw 23 vs 16N/cm.

- Higher bony contacts 59 vs 50% after 3 months implant insertion

Experimental investigation at 3, 6 and 12th month

Significantly stronger bone reaction to Cp

Retarded bone formation around the Ti6Al4V leaked out Al ion competing with calcium during early stage of calcification causing osteomalacia

Tantalum and Niobium : High degree of osseointegration

There was evidence of exaggerated macrophage reaction compared to Cp titanium.

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CERAMICS

(Calciumphosphate hydroxyapatite, Al2O3, Tricalcium phosphate)

• Makeup the entire implant

• Applied in the form of coating

Hydroxyapatite coated implant

• Gottlander 1994 – short term and longterm reaction

Short term reaction – Positive, enhanced interfacial bone formation

Long term reaction – Cp titanium 50-70% more interfacial bone compared to HA coated.

• Hahn J (1997) HA coated implant – 97.8%(6 yrs) clinical success.

Matter of concern.Matter of concern.

HA coating loosening – macrophage activation and bone resorption

• Beisbrock + Edgertson – Microbial adhesion, Osseousbreakdown, coating failure.

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POLYMERS

Not used

•Inferior mechanical properties

•Lack of adhesion to living tissues

•Adverse immunological reaction

Limited to

•Shock absorbing components – supra structure component

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IMPLANT

DESIGN CHARACTERISTIC

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Implant Design characteristic :

Implant design refers to the three dimensional structure of the implant.

Form, shape, configuration, geometry, surface macro structure, macro irregularities.

Cylindrical Screw shaped implants.

Threaded Non threaded.

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“Precision fit in the vital bone” Osseointegration

Cylindrical implants / press fit implants :

Severe bone resorption

Lack of bone steady state – micro movements

Alberktsson 1993 – continuing bone saucerization of 1mm -first

year, 0.5mm anually and thereafter increasing rate of resorption

upto 5 year followup.

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Threaded implants :

Documentation for long term clinical function.

Alteration in the design, size and pitch of the threads can influence the long term osseointegration.

Advantages of threaded implants

More functional area for stress load distribution than the cylindrical implants.

Threads improves the primary implant stability avoids micromovement of the implants till osseointegration is achieved.

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Non threaded

•Tendency for slippage

•Bonding is required

•No slippage tendency

•No bonding is required

Threaded

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IMPLANT SURFACE CHARACTERISTIC

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Implant surface characteristics

Topographic propertiesImplant surface texture

& roughness

Physical properties

Surface energy and charge

Physiochemical properties Implant surface chemistry

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Orientation of irregularities on the surface

Degree of roughness of the surface

Orientation of irregularities may give :

-Isotopic surface and anisotropic surface

Wennerberg (1996) Ivanoff (2001) : Better bone fixation (osseointegration) will be achieved with implants with an enlarged isotropic surface as compared to implant with turned anisotropic surface structure.

Surface topography

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1) Turned surface/ machined surface

2) Acid etch surface - HCl and H2SO4

3) Blasted surface – TiO2 / Al2O3 particles

4) Blasted + Acidetch surface (SLA surface)

- Al2O3 particles & HCl and H2SO4

- Tricalcium phosphate & HF & NO3

Different machining process results in different surface topographies

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5) Hydroxyapatite coated surface (HA)

6) Titanium plasma sprayed surface (TPS)

7) Oxidized surface

8) Doped surface

9) Nanosized hydroxyapatite coated surfaces www.indiandentalacademy.com

Additive surface treatment :

Titanium plasma spraying (TPS) hydroxyapatite (HA) coating

Substractive surface treatment :

Blasting with titanium oxide / aluminum oxide and acid etching

Modified surface treatment :

Oxidized surface treatment

Laser treatment

Ion implantation www.indiandentalacademy.com

Machined / turned surfaces : gold standard.

Moderately rough implant surfaces

• Roughness parameter (Sa)

0.04 –0.4 m - smooth

0.5 – 1.0 m – minimally rough

1.0 –2.0 m – moderately rough

> 2.0 m – rough

• Wennerberg (1996) – moderately rough implants developed the best bone fixation as described by peak removal torque and bone to implant contact.

• In vivo studies

Smooth surface < 0.2 m will – soft tissue no bone cell adhesion clinical failure.

Moderately rough surface more bone in contact with implant better osseointegration.

: For faster & firmer bone integration

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Carlsson et al 1988, Gotfredsen (2000) – positive correlation between increasing surface roughness and degree of implant incorporation (osseointegration).

Advantages of moderately rough surface :

Faster osseointegration, retention of the fibrin clot, osteoconductive scaffold, osteoprogenator cell migration.

Increase rate and extent of bone accumulation contact osteogenesis

Increased surface area renders greater osteoblastic proliferation, differentiation of surface adherent cells.

Increased cell attachment growth and differentiation.

Increased rough surfaces :

Increased risk of periimplantitis

Increased risk of ionic leakage / corrosion www.indiandentalacademy.com

Machined / turned surface

SEM x 1000 SEM x 4700

Cp Titanium

Surface roughness profile 5 m

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Titanium plasma sprayed coating (TPS)

The first rough titanium surface introduced

Coated with titanium powder particles in the form of titanium hydride Plasma flame spraying technique

6-10 times increase surface area. Steinemann 1988, Tetsch 1991

Roughness Depth profile of about 15m

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Hydroxyapatite coatings

HA coated implant bioactive surface structure – more rapid osseous healing comparison with smooth surface implant.

Increased initial stability

Can be Indicated - Greater bone to implant

contact area - Type IV bone - Fresh extraction sites - Newly grafted sites

SEM 100X

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Sand blasting Acid etch

The objective

Sand blasting – surface roughness (substractive method)

Acid etching – cleaning

SEM 1000X SEM 7000X

Lima YG et al (2000), Orsini Z et al (2000).

- Acid etching with NaOH, Aq. Nitric acid, hydrofluoric acid.

Decrease in contact angle by 100 – better cell attachment.

Acid etching with 1% HF and 30% NO3 after sand blasting – increase in osseointegration by removal of aluminium particles (cleaning).

Wennerberg et al 1996. superior bone fixation and bone adaptation

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Laser induced surface roughening

Eximer laser – “Used to create roughness”

Regularly oriented surface roughness configuration compared to TPS coating and sandblasting

SEM x 300

SEM x 300SEM x 70

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Physical characteristic :

•Physical characteristic refers to the factors such as surface energy and charge.

Hypothesis : A surface with high energy high affinity for adsorption show stronger osseointegration.

Baier RE (1986) – Glow discharge (plasma cleaning) results in high surface energy as well as the implant sterilization, being conductive to tissue integration.

Charge affects the hydrophilic and hydrophobic characteristic of the surface.

A hydrophilic / easily wettable implant surface : Increases a initial phase of wound healing.

Fact : Increase surface energy would disappear immediately after implant placement.

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Implant surface chemistry :

• Chemical alteration increases bioactivity increase implant bone anchorage.

Chemical surfaces :

• Ceramic coated – hydroxyapatite (HA), Calcium phosphate

• Oxidized/anodized surfaces with electrolytes containing phosphorous, sulfur, calcium, magnesium and flouride.

• Alkali + Heat treatment.

• Ionization, implantation of calcium ion, floride ions

• Doped surfaces with the BONE stimulating factors / growth factors.

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Anchorage Mechanism or Bonding Mechanism in Osseointegrated implants :

Biomechanical bonding

In growth of bone into small surface irregularities of implant surface three dimensional stabilization

Seen in :• Machined / turned screw implant • Blasted /Acid etch surface moderately

rough implant surface.

Based on :• Design characteristic Macrostructure

(Threads, vent, slots) • Surface characteristic Microstructure.

(Chemical surface treatmentwww.indiandentalacademy.com

Surface roughness at the micrometer level / nanometer level

Requirement :

Minimum size of

•50-100m cavities or pores complete bone tissue (ground substance + cellular components + Haversion system)

• 1-10m for calcified bone ground substance.

? At nanometer level - no experimental evidence

Some investigators – nanometer size rough surface can carry proper load. www.indiandentalacademy.com

Biochemical bonding Seen with certain bioactive implant surfaces like :

• Calcium phosphate coated implant surfaces

• HA coated implant surfaces

• Oxidized/ anodized surfaces

Bone bonding / Bonding osteogenesis

Biointegration :

•“Strong chemical bond may develop between the host bone and bioactive implant surfaces and such implants are said to be biointegrated”.

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Doped surfaces that contain various types of bone growth factors or other bone-stimulating agents may prove advantageous in compromised bone beds. However, at present clinical documentation of the efficacy of such surfaces is lacking : BMP = Bone morphogenetic protein.

Doped surfaces

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BONE FACTOR

• Bone quality bone with well

formed cortex and densely

trabaculated medullary spaces

• Bone quantity Refers to the

dimension of available bone in

reference to length, width and

depth.

Initial implant stability

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•Factors compromising the bone quality

Infection ,Irradiation &Heavy smoking

Branemark system (5 year documentation)

Mandible – 95% success

Maxilla – 85-90% success

Aden et al (1981) – 10% greater success rate in anterior mandible compared to anterior maxilla.

Schnitman et al (1988) – lower success rate in posterior mandible compared to anterior mandible

- posterior maxilla higher failure rates.

Difference in bone composition

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LIKHOM AND ZARB CLASSIFICATION 1985

Class I : Jaw consist almost exclusively of homogeneous compact bone

Class II : Thick compact bone surrounds

highly trabecular core

Class III : Thin cortical

bone surrounds highly

trabecular core

Class IV : Thin cortical

bone surrounds loose, spongy

core

D1 D2 D3 D4

MISCH CLASSIFICATION 1988

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According to Branemark and Misch

D1 and D2 bone initial stability / better osseointegration

D3 and D4 poor prognosis

D1 bone – least risk

D4 bone - most at risk

Jaffin and Berman (1991) – 44% failure in type IV bone

Selection of implant

D1 and D2 – conventional threaded implants

D3 and D4 – HA coated or Titanium plasma coated implants

Loss of osseointegration

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Osteopromotion :

Procedure to enhance the formation of bone approximating the implant surface :

• Bone regeneration techniques (using PTFE membrane)

• Bone growth factors like PDGF, IGF, PRP, TGF-B1 stimulates osteoprogenitar cells, enhance the bone growth.

• Stefini CM et al (2000) recommend to apply PDGF and IGF on the implant surfaces before placing into cervical bed. This method showed better wound healing and rapid osseointegration.

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Indications :

1) Localised ridge augmentation prior to implant placement

2) Treatment of periimplant bone defect.

Exposed implant surface

PTFE membrane Regeneration of bone

Increased bone to implant contact www.indiandentalacademy.com

Implantation bed / host bed

•Objective Healthy implant host site

•Nature of the host site - vascularity

- cellularity (osteogenic potential)

Two Factors

•Patient Considerations - Age

•History of proposed host bed – Previous irradiation

- Infection

- History of smoking

- Advanced ridge resorption

- Osteoporosis or osteoporotic like bone lesion www.indiandentalacademy.com

Age :

Old age – no poorer result

Extreme young age - Relative contraindication to insertion of implants.

Infrapositioning of implant because of alveolar growth

Wait till the completion of growth

Maxillofacial deformities : implant placement is delayed until the child is at puberty.

Only in selected cases

ex: Ectodermal dysplasia

Anterior part of the jaw + over denture therapy.

Bone anchored hearing aids :

2-3 year old child.www.indiandentalacademy.com

Smoking and osseointegration :

• History of smoking may affects the healing response in osseointegration.

• Lower success rates with oral implants

• Mechanism behind

Vasoconstriction

Reduced bone density

Impaired cellular function

• Mean failure rates in smoker is about twice than in non smoker.

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Radiation therapy and osseointegration :

• Jacobsson (1985) previous irradiation – relative contraindication for implant placement.

• Expected success rate 10-15% lower than the non irrradiated patients.

Number of factors to be considered :

• Dose and fraction of irradiation

• Timing from radiotherapy to implant surgery

• Anatomic region in which the implant to be inserted

• Loading factors and handling of the soft tissue.

Full course radiotherapy (50-65Gy) Not contraindicated.

> 65 Gy critical for implant survival.

• Johnson (1987) Surgical risk 1m before and 6m after,

Low risk 6m to 1.5 yr

Increased risk there after. www.indiandentalacademy.com

Hyperbaric oxygen therapy (HBO) :

• HBO Elevates the partial pressure of oxygen in the tissues.

• Granstrom G (1998) HBO can counteract some of the negative effect from irradiation and act as a stimulator for osseointegration.

• Role of HBO in osseointegration

– Bone cell metabolism

- Bone turnover

- Implant interface and the capillary network in the implant bed

(angiogenesis)

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SURGICAL CONSIDERATIONS

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Objective:

Minimum tissue violence – osseointegration

Controlled surgical technique

Surgical skill / technical excellence

Parameters :

• Profuse irrigation for continuous / Adequate cooling

•Use of well sharpened drills and use of graded series of drills

Violent surgical techniques

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• Slow drill speeds

• Proper drill geometry

• Intermitent drilling

Eriksson R.A :

• Drill speed < 2000 rpm, tapping at 15 rpm.

• Cooling during tapping and insertion of screw

Others

• Cooling the irrigants

• Using internally irrigated drills

Violent surgical technique

• Frictional heat / overheating increased temperature rise in bone wide zone of necrosis fibrous tissue, primary failure of osseointegration. www.indiandentalacademy.com

Erickson RA www.indiandentalacademy.com

Critical temperature for bone necrosis

• Previously 560 to 700 for 1 min.

• 560C critical temperature for bone necrosis Irreversible bone damage.

• Recently 470C for 1 min.

Denaturation of alkaline phosphate enzyme inhibition of Alkaline Ca synthesis Loss osseointegration (Errickson 1986, Albrektsson 1984) www.indiandentalacademy.com

Insertion torque

Insertion torque is high – removal torque is low.

Poor osseointegration

High torque is used stress / compression in bone

Holding power of implant will fall.

45 N/cm

Moderate torque should be used

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IMPLANT

LOADING

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Loading condition

Objective : “No loading while healing” successful osseointegration.

Movement of the implant within the bone – fibrous tissue encapsulation rather than osseointegration.

Premature loading leads to implant

movement

The end result “Soft tissue interface”

“Bony interface”

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Branemark, Albrektson – two stage implant insertion.

First stage – Installation of fixture into bone

Second stage – Connection of abutment to the fixtures

Maxilla 6 months

Mandible 3 months

Misch – Progressive / Gradual loading

Different Philosophies regarding Loading conditions

Suggested in Softer boneless number of implants to be used

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Immediate functional loading protocol

Clinical trials successful osseointegration

(95-100% success rate- Completely edentulous patients)

Bone quality is good

Functional forces are controlled

More favourable in mandible compared to maxilla

Over loading – Stress concentration, undermining bone resorption without apposition (Branemark 1984)

To decrease the bio mechanical loadProsthetic design considerationsCantilever length may be shortened or eliminatedNarrow occlusal tableMinimizing the offset loadIncreasing the implant numberUse of wider implant with D4 bone compared to D1 & D2www.indiandentalacademy.com

Success criteria of implants :

Schuitman and Schulman criteria (1979)

1) The mobility of the implant must be less than 1mm when tested clinically.

2) There must be no evidence of radiolucency

3) Bone loss should be less than 1/3rd of the height of the implant

4) There should be an absence of infection, damage to structure or violation of body cavity, inflammation present must be amneable to treatment.

5) The success rate must be 75% or more after 5 years of functional service.

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Albrektson and Zarb G (1980)

1) The individual unattached implant should be immobile when tested clinically

2) The radiographic evaluation should not show any peri-implant radiolucency

3) Vertical bone loss around the fixtures should be less than 0.2mm annually after first year of implant loading.

4) The implant should not show any sign and symptom of pain, infection, neuropathies, parastehsia, violation of mandibular canal and sinus drainage.

5) Success rate of 85% at the end of 5 year observation period and 80% at the end of 10 year service.

Smith and Zarb (1989)

6) Implant design allow the restoration satisfactory to patient and dentist. www.indiandentalacademy.com

METHODS OF EVALUATION OF OSSEOINTEGRATION

Invasive method

•Histological section

•By using torque gauges

•TEM (transmission electron microscopy)

•Pullout test

•Histomorphometric

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Non-invasive methods :

•Radiographs

•Periotest

•Reverse torque

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•Resonance frequency analysis

•Dynamic model testing

•Impulse testing

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List of References :

Osseointegration in clinical dentistry – Branemark, Zarb, Albrektsson

Osseointegration and occlusal rehabilitation – Sumiya Hobo

Contemporary Implant Dentistry – Carl. Misch

Endosseous implants for Maxillofacial reconstruction – Block and Kent

Implants in Dentistry –Block and Kent

Dental and Maxillofacial Implantology – John. A. Hobkrik, Roger Watson

Endosseous Implant : Scientific and Clinical Aspects – George Watzak

Optimal Implant Positioning and Soft Tissue management – Patrik Pallaci

Osseointegration in craniofacial reconstruction. T. Albrektssson.

Osseointegration in dentistry : an introduction : Philip Worthington, Brein. R. Lang, W.E. Lavelle.

IJOMI 2005; 20(2): 307-311

IJOMI 2005; 20: 425-31

IJP 2004; 17: 536-543. www.indiandentalacademy.com

IJOMI 2000; 15(1): 76-94.

IJOMI 2000; 15: 675-690.

IJOMI 1988 ; 3 : 231-246

IJP, 1998 ; 5 : 491-500.

JPD, 1983, 50 : 399-410.

D.C.N.A., 1986 ; 10-34, 151-160

D.C.N.A., 1992 ; 36, 1-17

JPD, 1983 ; 50 : 108-113.

JPD, 1983; 50:832-37.

IJP, 1990 ; 3 : 30-41.

IJP, 1998 ; 11 :391-401.

J. Perio. Rest 1981 ; 16 : 611-616.

JPD 1993 ; 69 : 281-288.

Int J. Periodont Rest Dent 1995 ; 15 : 345-361.

Int J Oral Maxillofac Surg. 1986 ; 144 : 274-282.

Int J Periodont Restorative Dent 1998 ; 18 : 553-563.

J Periodontal 1997 ; 68 : 591-597.

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