This presentation includes various surface treatments and functional coatings on dental titanium implants to enhance osseointegration .

1. SURFACE TREATMENT
OF IMPLANTS
DR. SABNOOR AUJLA
M.D.S III YEAR
MMCDSR, MULLANA.

2. SURFACE TREATMENT
SURFACE COATING

3. INTRODUCTION
The clinical success of dental implants is dependent on successful
osseointegration.
An important parameter for achieving osseointegration is the
establishment of direct contact between the surface of the implant
and the surrounding bone.
There have been numerous studies indicating that Implant Surface
Roughness Affects The Rate Of Osseointegration.
Various surface modifications that beneficially alter the topography, hydrophilicity and
outer coating of dental implants in order to enhance the osteoblastic migration,
adhesion, proliferation and differentiation in healthy as well as compromised bone by
either distance and contact osteogenesis.

4. SURFACE MODIFICATIONS OF IMPLANTS
Commercially available implants have been categorized according to the
Roughness Value (Sa) into 4 groups by Albrektsson & Wennerberg (2004)
into
• Smooth (Sa < 0.5 μm)
• Minimally rough (Sa = 0.5-1.0 μm)
• Moderately rough (Sa = 1.0-2.0 μm)
• Rough (Sa > 2.0 μm).
Based on the Scale Of The Features, the surface roughness of implants can
be divided into
• Macro
• Micro
• Nano

5. (Aljateeli and Wang, 2013)

6. GOALS :
1)Cleaning the implant surface and increasing its bioactivity.
2)Roughening surfaces to increase effective/functional surface area.
3)Accelerate osteoblasts adhesion and proliferation
4)Producing beneficial surface compressive residual stress.
5)Exhibiting higher surface energy, higher surface chemical and physical activities.
Enhancing fatigue strength, fatigue life, due to compressive residual stress.

7. MACRO-SURFACE MODIFICATIONS
Implant design and topography:
• Thread shape
• Thread depth
• Thread width
• Thread pitch
• Thread helix angle
• Crestal module
• Rough or Smooth neck
• Microthreads : Machined surface
The macrotopography of an implant is determined by its visible geometry, for
example, threads and tapered design. Appropriate macrogeometry combined
with adequate implant drill hole preparation is the fundamental basis of clinical
success in dental implantology.

8. Favorable forces
Three types of loads are generated at the bone and implant interface - Compressive, Tensile and Shear
Forces (Misch).
Wolff observed a direct relationship with increasing mechanical loading and reactive bone formation.
In the presence of stress, bone formation is seen while a decrease in stress or function is observed
to have the opposite effect with loss of bone density (Wolff, 1892).
Efforts are therefore, focused on increasing compressive forces and minimizing the tensile
and shearing forces which may weaken the bone to implant interface.
As previously mentioned, efforts to attain this have been made through tapering of the implant body
and adjusting the thread design (Holmgren et al., 1998, Misch, 2008, Lemons, 1993).

9. Thread shape is determined by the thread thickness and thread face angle.
Available shapes -- V-shape, Square shape, Buttress, Reverse buttress and Spiral.
Thread shape determines the face angle.
Face angle is the angle between the face of a thread and a plane perpendicular to the
long axis of the implant.
Studies have shown altering the face angle can have an effect on the forces at
the bone to implant interface.
• A relatively small face angle will tend to increase tensile and compressive
type forces,
• while increasing the face angle has been shown to result in an increase of
shearing type forces along the implant to bone interface. This concept has
been observed to occur regardless of the thread shape within their
respective groupings
(Bumgardner et al. 2000).

10.  V-threads are strong, but they transmit more shear forces to the
surrounding bone.
 Square-thread forms transmit occlusal forces with less shear forces
than V-threads, though they are not as strong as V- and buttress-
thread forms due to their smaller cross-section at the base of the
thread.
 Buttress threads are the strongest thread form for a given size
because of their larger base cross-section, and because they
minimize shear forces in a manner similar to square threads. They
combine excellent primary stability with the best features of both V-
and square-thread forms.

11. According to Misch, V-shaped threads typically have a face angle of 30 degrees in
implant dentistry which tends to introduce greater shearing forces to the interface than in
the case of the reverse buttress which typically has a face angle of 15 degrees or the
square thread which does not posses a face angle of any noteworthiness and therefore
the smallest amount of shearing forces amongst the group.
The axial forces transmitted in the V-shaped and reverse buttress thread form are
mainly an interplay of compressive, tensile, and shearing (Misch, 2008). These shearing
forces have been found to ultimately result in greater defect formation (Hansson and
Werke, 2003).
The ideal thread shape with respect to transmission of compressive forces generated at the
interface has been shown to be the square and buttress threads (Barbier and Schepers, 1997).

12. Thread depth is defined as the distance
from the tip of the thread to the body of the
implant.
Thread width is the distance in the same
axial plane between the coronal most and the
apical most part at the tip of a single thread.
The role thread depth plays are proposed to
occur on insertion and BIC of the implant.
A shallow thread will be easier to insert into
dense bone without having to use a drill to tap
the site prior to insertion.
A deep thread will allow for much greater
primary stability specifically for situations such
as soft bone or immediate implant sites
(Abuhussein et al., 2010, Misch, 2008).

13. Thread pitch (Jones, 1964)
The distance from the center of the thread to the center of the next thread, measured parallel to the
axis of a screw.
IN IMPLANTS WITH EQUAL LENGTH, THE SMALLER THE PITCH THE MORE THREADS THERE
ARE.
Implants with more threads (i.e. smaller pitch) were found to have a higher percentage of BIC
Another study using FEA looked at implant pitch as it related to resistance to vertical forces and
found with increasing thread pitch, the resistance to vertical forces was weakened. (Ma et al.,
2007)

14. Lead – The axial distance that the implant advances in one complete turn.
In a single-threaded screw, lead is equal to pitch, However, this is not always the
case, some implants are made to have a double or triple thread design in which two
or three threads run parallel to each other.
The reasoning behind this is to maintain the increased number of threads along the
implant surface, which will help to maintain a high level of resistance to vertical
and maintain a high level of BIC at the same time as allowing for increased speed of
implant insertion

15. Micro threads
Recently, the concept of microthreads in the crestal portion has been introduced to
maintain marginal bone and soft tissues around the implants. In presence of a smooth
neck, negligible forces are transmitted to the marginal bone leading to its resorption.
The presence of retentive elements at the implant neck will dissipate some forces
leading to the maintenance of the crestal bone height accordingly to Wolff’s law.
Microthreaded implants increase bone stress at the crestal portion when compared
with smooth neck implants.

16. Machined surface
 Lathing, Milling, Threading
 Machined implant surfaces are characterized by more grooves and valleys which
provide mechanical resistance through bone interlocking
 Properties of machined surface depends upon manufacturing tools, tool pressure,
bulk material, thickness and temperature choice of lubricant and machining speed .
 Typical Sa values for machined surfaces are 0.3-1.0 μm.
 The surface oxide consists of a 2-10 nm thick mostly amorphous layer of TiO2
 osteoblastic cells are rugophillic—they grow along the grooves existing in the
surface
 Hence a long waiting time (3-6 months )

17. TECHNIQUE DISCRIPTION PARTICLE DISRIPTION
SANDBLASTING compressed air that creates a Blasting media -Alumina (Al2O3)
or silica (SiO2) Surfaces blasted
with 25 μm particles
GRIT BLASTING Surface of the implant is
bombarded with hard dry particle
or particles suspended in a liquid,
through a nozzle at high velocity
means of compressed air.
alumina, silica, Titanium oxide,
calcium
phosphate particles are used.
SHOT PEENING Modified method of grit
blasting but has more
controlled peening power,
intensity and direction.
Alumina particles(25-
75 μm)
MICRO-SURFACE MODIFICATIONS

18. TECHNIQUE DISCRIPTION
ACID ETCHING Immersing it in strong acids (e.g., nitric
acid, hydrochloric acid, hydrofluoric
sulfuric acid,
and their mixtures) for a given period of
time, creates a micro-roughness of 0.5–
μm.
The surface is pitted
by removal of grains
and grain boundaries
of the implant surface.
It also cleans the
implant surface, e.g.,
removes deposits.
DUAL ACID
ETCHING
TECHNIQUE
Immersion for several minutes in a mixture of concentrated
HCl and H2SO4 heated above 100 °C
SANDBLASTED AND
ACID ETCHED
SURFACE (SLA)
In SLA protocol, the titanium dental implant surface is first
sandblasted with large grits 250 - 500 μm, making the
surface grossly rough. Then, the implant is acid-etched by
HCL/H2SO4. Acid etching leads to micro texturing and
cleaning.
.

19. Other Chemical Treatments
Solvent cleaning
Removes oils, greases and fatty surface contaminants remaining after manufacturing process. Organic
solvents (aliphatic hydrocarbons, alcohols, ketones or chlorinated hydrocarbons), surface active detergents
and alkaline cleaning solutions.
Alkaline etching
Treatment of titanium in 4-5 M sodium hydroxide at 600°C for 24 hours produce sodium titanate gel of 1
μm thick, with an irregular topography and a high degree of open porosity.
Boiling alkali solution (0.2 M sodium hydroxide, 1400°C for 5 hours) produce a high density of
nanoscale pits on the titanium.
When the alkali treatment is preceded by etching in hydrochloric acid/sulfuric acid, porosity of the final
surface is found to increase.
Passivation treatments
For obtaining a uniformly oxidized surface to improve corrosion resistance.
Immersion of titanium for a minimum of 30 minutes in 20-40 vol% solution of nitric acid at room
temperature.
After passivation, surface of the implant should be neutralized, thoroughly rinsed and dried. Nitric
acid passivation has no major influence on the overall surface topography of titanium surfaces.
In addition to nitric acid passivation, heating in air at 400- 600 °C or ageing in boiling deionized water for
several hours can be used as an alternative passivation treatments (heat treatment) .

20. Electrophoresis
Electrophoretic deposition (EPD)
HA powders dispersed in a suitable solvent and coatings are obtained by applying voltages of the
order of 20- 200V. The coating density is improved by a further sintering at 600°C or above.
Using this method, small particles as well as large particles can be deposited.
Advantages
Simplicity and low cost
Ability to coat with uniform thickness, wide range of thicknesses, complex shapes .
Ease of chemical composition control.
Mechanism -- Two steps.
1st -- the migration of particles (which acquire positive charge) under the
influence of an electric field applied to a stable colloidal suspension.
2nd -- deposition on the metallic substrate.
Driving force of the deposition process is the applied electric field. Depending
on the mode and sequence of voltage applied, the electrophoretic deposition
can be carried out at i) constant voltage or ii) dynamic voltage.

21. Thermal treatments
Commercially pure titanium can be thermally annealed up to 1000°C to form
oxide layer composed of anatase and rutile structures of TiO2. The titanium
oxide that is formed on the surface is crack-free and uniformlyrough.
Average roughness when the titanium is annealed at 600 °C and 650 °C for 48
hours was 0.90 and 1.30 μm, respectively.
Average roughness of untreated sample was 0.08 μm.
Thermal treatment at 600°C and 650°C for 48 hours is considered
appropriate for implanted materials.

22. Titanium Plasma Spray
(TPS)
A gas plasma stream is first created by having an electrical
between a finger-type
tungsten cathode and a nozzle-type copper anode inside the
plasma torch.
Inject titanium powders into a plasma torch at high
temperature. The titanium particles are projected on to the
surface of the implants where they condense and fuse
together, forming a film about 30μm thick.
The thickness must reach 40-50μm to be uniform.
SPUTTER DEPOSITION
RADIOOR MAGNETIC
Atoms or molecules of a material are ejected in a vacuum
chamber by bombardment of high- energy ions.
Useful technique for the deposition of bioceramic thin films
BIOMIMETIC
DEPOSITION
hydroxyapatite and other calcium phosphate
on surfaces of implant materials in simulated body
fluid (SBF) under physiological conditions of
temperature and pH.
Ca–P coating requires an immersion period of about
14 – 28 days. The Ca/P ratio for HA biomimetic
was1.51 . The thickness of HA coatings - 20 to 25μm.

23. NANOTOPOGRAPHY
 Nanotechnology has received a wide attention in
public and scientific media.
 Naotopography of dental implants is thought to
influence the cell-implant interactions at the cellular
and protein level.
 It has been hypothesized that different
osteocinductivity of micro and nanoscle implant
surface may influence the osteoblast activity.

24. DISCRETE CRYSTALLINE
SEPOSITION (DCD)
 BIOMET
 CaP particles of 20-100nm are deposited on a double
acid-etched surface bu a sol gel proccess DCD.
 CaP particles make up roughly 50% of the surface area
and exert a higher adhesive force to the implant
surface than former techniques to deposit CaP.

25. LASER ABLATION
 BioHorizons: uses this manufacturing technique which
focuses on improving the integration of dental implants
in the surrounding soft tissue.
 Therefore, nanoscale surface manufacturing technique
have been transferred to the implant collar.
 The neck of the Laser-Lok implant has been processed in
a laser micromachining step to generate a pattern of
micro- and nanoscale miro-channels.
 These microchannels have been proposed to act as a
biological seal by elicting the attachment od CT and bone
and inhibiting epithelial downgrowth.
The shock wave induces compressive residual stress that penetrates beneath the surface
and strengthens the implant, resulting in improvements in fatigue life and retarding in
stress corrosion cracking occurrence.

26. ANODIC OXIDATION
 NOBEL BIOCARE
 THE IMPLANT SURFACE IS ELECTROCHEMICALLY
MODIFIED BY ANODIC OXIDATION to increase the
thickness of titanium oxide layer from 17-200nm in
conventional implants 600-1000nm.
 Thus, a porus surface microstructure with pore size 1.3-
2.00 mm and moderate degree of roughness is generated.
 The implant surface is also referred to as TITATIUM
POROUS OXIDE
 In this technique, the implant is exposed to an electric
circuit with the implant serving as anode.

27. TITANIUM OXIDE BLASTED AND
ACID-ETCHED IMPLANT
 DENTSPLY , TiOblast Impants.
 The specific surface texture is a result of 2 substractive
sequential manufacturing steps.
 Titanium oxide blating produces a microscale surface
roughness
 The subsequent etching with Hydroflouric acid shapes
the nanostructure of the implant.

28. PHOTOFUNCTIONALIZATION
 UV treatment of dentl implants surfaces enhances
bioactivity and osseointegration by altering the
titanium oxide on the surface.
 UV light is believed to enhance the osseoconductivity
 It reduces the degree of surface hydrocarbon and
increases surface energy and wettability.
 It raises the level of protein adsorption and cellular
attachment to the implanys.

29. SURFACE COATINGS
 They tend to miminc the biochemical and nanostructural
architechture of human bone.
 Coatings comprises of specific agents, drugs, proteins and growth
factors.

30. HYDROXYAPPETITE
AND
NANOCOMPOSITE
COATINGS
HA stable biological form of CaP and strengthens the organic
matrix by mineralisation. It generates a hydrophilic monolayer
multiphosphoric acid molecules on the implant surface thus
imitating natural HA.
Nanotechnology is also plays an imporatnt part to compose
nanoscle hydroxyappetite crystals(nHA) on implant surface.
It is used as a singe compond coating or a part of the
in combination with carbon nanotubes, collagen, titatinum
dioxide or ceramic oxide (Nanocomposite)
GROWTH FACTORS Growth factors on the implant surface like:
• BMP2 contains bimimetic CaP led to sustianed ossification.
• Transforming Growth Factor (TGF beta) ehanced BIC and
increase bone volume around implant.
• Fibroblast Growth Factor (FGF-2) influences the proliferation
osteoblasts.
• Platelet Derived Growth Factor (PDGF) exhibits enhanced
osteogenic differentiation and proliferation as compared to
controlled titanium implants

31. MESSENGER
MOLECULES
Sclerostein is a messenger molecules that mediates the
osteoclast interaction. It is secreted by osteocytes and inhibits
osteoblatic activity .
Anti-Sclerotin coating on implant surface enhance
osseointegration of dental implants.
Extracellular Matrix
Proteins
Implants coated with extracellular matrix proteins have shown a
positive effect in peri-implant bone formation.
De Barros et al reported increase in bone volume and
mineralization for collagen type II coated implants compared to
uncoated controls in dog
Fluoride
treatment
.
Titanium is very reactive to fluoride ions, forming soluble
TiF4. The chemical treatment of titanium in fluoride
solutions enhances the osseointegration of dental

32. DRUG COATINGS • Statins coating claims to trigger the local liberation of BMP
promoting osseointegration.
• Bisphosphonates are antiresorptive drugs that influemce bone
metabolisms by inhibition of osteoclasts. (Osteoporosis
patients)
• Zolendronate HA coated implants exhinited higher BIC in an
osteoporotic rat model ( Stadlinger et al )
• Tetracycline-HCl -- decontamination and detoxification of
contaminated implant surfaces.
PEPTIDE Resemble fragments of larger proteins.
• RGD peptide is an importsnt sequence of extracellular matrix
proteins that acts as a binding site for integrin receptors in
adhesion and migration of osteogenic cells.
Schliephake et al reported implants with RGD coating showed
higher BIC than machined titanium implants.
• Human Beta Defence (HBD Peptide) coating on implants
antibacterial effects on epithelial cells and promotes
proliferation of osteoblasts.

33. Summary
The surface roughness values produced in each type of surface modification technique-

35. Conclusion
The central focus of implant development is to minimize bacterial
adhesion while promoting recruitment, adhesion, and proliferation
of osteogenic as well as fibroblastic cells in order to gain a high
degree of hard and soft tissue integration. To guarantee long-term
success in clinically challenging conditions, the development of
multifunctional surface modifications and coatings is necessary. The
goal of future research is to design a single polyvalent implant type
with enhanced clinical behavior in regard to osseous and fibrous
integration and prevention of peri-implantitis.

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focusing on topographic and chemical properties of different
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