implant surface vs osseointegration

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GOOD MORNING

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GOOD MORNING

IMPLANT SURFACE TREATMENTS

vs

OSSEOINTEGRATION

Presented by

Dr. MAHINDER & PHANINDRA

PG- Dept. of Prosthodontics

Mamata Dental college and Hospital

Contents

• Introduction

• Classification of implant surfaces

• Methods to alter implant surfaces

• Evaluation of the interface

• Conclusion

• References

Introduction

Definition:

Osseointegration:

The apparent direct attachment or connection of osseous tissue to

an inert, alloplastic material without intervening connective tissue.

- GPT 8

• The concept of Osseointegration was discovered by

• Per- Ingvar Branemark and his co-worker and, has had a

dramatic influence on clinical treatment of oral implants.

• The First generation titanium implants which were machined

with a smooth surface texture.

• Implant surfaces have been recognized to play an important

role in molecular interactions, cellular response and Osseo

integration.

• The Second generation implants with surface modification

can accelerate and improve implant osseointegration.

• Implants underwent mechanical blasting, acid etching,

bioactive coatings, more recently , laser modified surfaces.

• The main objective for the development of implant

surface modifications is to promote Osseo integration,

with faster and stronger bone formation.

• Furthermore, it accelerates the bone healing and thereby

allowing immediate or early loading .

CLASSIFICATION OF IMPLANT SURFACES

1. Implant materials

2. Based on chemical composition

3. Based on Biocompatibility

4. Based on implant surface texture

5. Based on implant surface irregularities

6. Based on the orientation of surface irregularities on

implant surface

7. Based on surface roughness on implant surfaces

I.Implant materials

Metals Ceramics Polymers

Chemical composition

Biological compatibility

Bio inert Bio tolerant Bio active

Based on Biocompatibility

1.Biotolerant Ex:Gold,CobaltChromium,Stainless steel,Zirconium,Niobium

2.Bioinert Ex:zirconium, alumina, ceramics, titanium,stainless steel,gold etc

3. Bioactive Ex: Hydroxyapatite, glassceramic, bioglass etc..,

Bioinert and Bioactive materials

are osteoconductive in nature.

Based on texture obtained, the implant surface can be

divided as:

1. Concave texture ( Additive treatments like

hydroxyapatite (HA)coating and titanium plasma spraying)

2. Convex texture (Subtractive treatment like

etching and blasting)

Based on the orientation of surface irregularities, implant

surfaces are divided as:

1. Isotropic surfaces: have the same topography independent

of measuring direction.

2. Anisotropic surfaces: have clear directionality and differ

considerably in roughness.

Wennerberg and coworkers have classified implant

surfaces based on the surface roughness as:

1. Minimally rough (0.5-1 mm)

2. Intermediately rough (1-2mm)

3. Rough (2-3 mm)

Methods to increase the surface roughness

1. Blasting

2. Chemical etching

3. Porous surfaces

4. Plasma-sprayed surfaces

5. Ion-sputtering coating

6. Anodized surface

1.Blasting :

• Blasting implant surface with particles of various diameters is one of

the most frequently used methods of surface alteration.

• Various ceramic particles have been used such as Alumina,

Titanium oxide and Calcium phosphate particles.

2. Chemical etching

• Etching with strong acids such as HCl, H2SO4,HNO3 and

HF is used for roughening dental implants.

• Acid-etching produces micropits on implant surfaces with

sizes ranging from 0.5 to 2 μm in diameter. Acid- etching

has been shown to greatly enhance Osseointegration.

• Recently a new surface was introduced that was sandblasted

with large grit and acid-etched (SLA).

• This surface is produced with large grit (250-500 micro-

metres) blasting process and followed by Hydrochloric and

sulfuric acid.

3. Porous surfaces

• These are produced when spherical powder of the

metallic/ceramic material becomes a coherent mass within the

metallic core of the implant body.

• These are characterized by pore size, shape, volume and depth,

which are affected by the size of the spherical particles and the

temperature and pressure of the sintering chamber.

Advantages

1. A three dimensional interlocking interface in

bone is observed.

2. Shorter healing time.

3. Provide space ,volume for cell-migration and

attachment and thus support contact osteogenesis.

4. Plasma-sprayed surfaces

• Plasma-spraying is a technique in which hydroxyapatite (HA) ceramic

particles are injected into a plasma torch at high temperature

approximately 15,000-20,000 K and projected on to the surface of the

titanium where they condense and fuse together, forming a film.

• Plasma-sprayed coatings can be deposited

with a thickness of about 50–100 μm.

5. Ion-sputtering coating

• It is the process by which a thin layer of Hydroxyapatite can be

coated onto an implant substrate.

• This is performed by directing a beam of ion onto an HA block

that is vaporized to create plasma and then recondensing this

plasma onto the implant.

6.Anodized surface:

• Oxidation process can be used to change the characteristic of

the oxide layer and make it more biocompatible.

• This is carried out by applying a voltage on the titanium

implant immersed in the electrolyte.

• This results in a surface with micropores of

variable diameter and demonstrates lack of cytotoxicity

and increased cell attachment and proliferation.

Advantages of increased roughness:

1. Increased surface area of implant adjacent to bone.

2. Improved cell attachment to bone.

3. Increased bone present at implant interface.

4. Increased biochemical interaction of implant with bone.

Methods

Methods to alter Implant surfaces

1. Physicochemical

2. Morphologic or Biochemical

1.Physicochemical

• This method involves the alteration of surface energy,

surface charge, and surface composition with the aim of

improving the bone-implant interface.

• The method employed is the Glow discharge treatment, in

which materials are exposed to ionized inert gas, such as

argon.

2.Morphological

• This method involves in alteration of surface morphology and

roughness to influence cell and tissue response to implants.

• Advantage : This method prevents the epithelial growth on

dental implants.

Evaluation of interface

Most commonly used methods to assess the quality of

Osseo integration.

1.Biomechanical test

2.Histomorphometric analysis

Biomechanical test

1.Pull-out test

2.Push-out test

3.Torque measurement

RADIOGRAPHS PERIOTEST & REVERSE TORQUE

4.Resonance frequency analysis

It consists of a post which is screwed into the implant and a transducer/receiver unit. It works by emmiting a

radio frequency and then reads the amplitude which returns to the unit from the implant. Basically it reads

and gives a number that is associated with the “solidness” of the implant.

Conclusion

• There are number of surfaces commercially available for

dental implants.Various methods modifying the implant

surface have greatly influenced the quality of clinical

service in implant prosthodontics.

• Implant surface characterization and working knowledge

about how surface and bulk biomaterial properties inter

relate to implant osseo integration represent an important

area in implant based reconstructive surgery

REFERENCES:

1)INT J Oral Maxillofac Implants 2000;15:675-690

2)Indian Journal of Dental Sciences.(March 2012) 3) Wennerberg A, Albrektsson Suggested guidelines for the topographic evaluation of implant surfaces.

4)Int J Oral Maxillofac Implants 2000;15:331-44.

5) Brunette DM. The effects of implant surface topography on

the behavior of cells. Int J Oral Maxillofac Implants1988;3:231

6) Puleo DA, Thomas MV. ImplantSurfaces. Dent Clin North

Am 2006;50:323-338.

Thank you