Dr. Lama El Banna Fifth-year second semester Al Azhar University Palestine Any Question inbox me here lama1997bana@gmail.com

1. Classification of endosseous root
form implants (2)
• Endosseous root form implants are the most widely used
implants. Several research projects and clinical trials have been
done and continue to be done, to develop an optimal implant
design.
• There are many parameters which differentiate one root form
implant from another, and dentists practicing or willing to practice
clinical implantology should know these features and their benefits
to successfully choose the correct implant design.
• Root form implants can be classified as follows:
1

2. Root Form Implants Classified on The Basis
of Surface Design:
Non-threaded implants
• These implants do not have any threads along their body,
and thus are tapped into the prepared osteotomy slot. The
non-threaded implant offers the advantages of more
surface area and more bone implant–surface contact
percentage (e.g. the Endopore implant).
• The limitations of these implants are that they require
technique-sensitive placement and only a conventional
two-stage protocol can be practised with these implants.
2

3. 3

4. Threaded implants
⮚These implants are the most widely used and contain
threads along the implant body. These implants are
screwed into the prepared osteotomy site. (e.g.
Biohorizons implants, Nobel Biocare implants, etc.).
⮚Threaded implants offer several advantages over the non
threaded implants including ease of placement, more
initial stability even in low-density bone, and the facility to
practice non-submerged and immediate to early loading
protocols.
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5. 5

6. Parallel body implants
⮚The bodies of these implants remain almost parallel, without
any taper.
⮚These implants offer the advantage of more surface area
compared to tapered implants of the same diameter.
⮚The only disadvantage with these implants is their technique-
sensitive placement – if osteotomy for this implant slightly gets
widen with the final drill, the primary stability of this implant
gets reduced or lost.
⮚Further, even in the medium density bone, more no. of drills
need to be used for osteotomy preparation when compared to
the tapered body implant
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7. 7

8. Tapered body implants
⮚The body of this implant tapers as it progresses from the
implant platform to the apex.
⮚These implants require minimal drilling and achieve high
primary stability even in low-density bone.
⮚The only disadvantage of these implants is their smaller
surface area compared to parallel body implants of similar
diameter
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9. 9

10. Root form implants classified on the basis of
implant connection
⮚Implants can be classified as implants with the external
connection and implants with internal connection.
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11. External connection (external hex)
⮚In these implants, the implant connection emerges above the
implant platform and acts as the male part, because all the
implant components like abutment, healing screw etc. get
engaged over and around this connection and are fixed using
a connection screw, which is engaged in the prepared threads
through the implant connection into the implant body.
⮚Conventionally most root form implants carry external
connections, and it is claimed that these implants can better
withstand the forces and do not get fractured
11

12. 12

13. Internal connection (internal hex)
⮚These implants show the connection which remains inside
the implant body and acts as the female part, because the
part of all the implant components goes into the implant
connection and get engaged, further the components are
fixed using the connection screw
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14. 14

15. Root form implants classified on the basis of
connection design
• The design of the implant connection can vary from
system to system.
15

16. Triangular design
• It has three faces,
thus the abutment
can be fixed at any of
the three oriental
positions
Hexagonal design
• It has six faces, thus
the abutment can be
fixed at any of the six
oriental positions
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17. Octagonal design
• It has eight faces, thus the abutment can be fixed at any
of the eight oriental positions.
17

18. Smooth surface/ non-hex (cold-weld)
design
• This does not have any faces but is a smooth-surface,
tube-in-tube connection. It does not need any connection
screw but the abutment gets firmly engaged and cold-
welded into the implant connection.
• It is claimed that this connection forms a tight seal at the
implant abutment–connection interface and prevents
microbial growth in the connection.
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19. 19

20. Morse taper connection
• This is a combination of both hexed and non-hexed (cold-
welded, tube-in-tube) connections.
• It has the hex in the deepest half of the internal
connection as the anti rotational feature, where as the
smooth non-hexed surface in the crestal half of the
connection makes a tight seal to prevent bacterial growth
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21. 21

22. Root form implants classified on the basis of
implant material
Titanium alloy implants
• Most of the root form implants being currently used are made of
pure titanium or titanium alloys
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23. 23

24. Zirconium implants
• Zirconium also osseointegrates with bone like titanium. It
offers additional advantages, such as high aesthetics, and
can be used in patients with titanium allergy.
• The only disadvantage with the zirconium implant is that it
is made in a single body, because zirconium components
which can be screwed to the zirconium body have not yet
been developed
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25. 25

26. Root form implants classified on the basis of
thread design
• Implants with various thread designs are available in the
market and each design offers some advantages.
26

27. Square/U-shaped (non-cutting) thread
implants
• These threads increase the surface area as well the
primary stability of the implant.
• The only disadvantage of these implants is that a special
thread former (bone tap) is used to make threads in the
finally prepared osteotomy to incorporate the implant
threads into it, especially when the implant is being
inserted in high-density bone
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28. 28

29. Sharp/V-shaped (cutting) thread (self-
tapping) implants
⮚These sharp threads are self-tapping and do not require
any additional tool to prepare threads in the bone,
because being sharp, they get easily engaged in the bone
29

30. 30

31. Variable thread (corticocancellous)
design implants
• These implants contain sharp, self tapping, deep threads with
high pitch value (more space between two threads) at the apical
third of the implant to tap into the prepared osteotomy and to
achieve high primary stability in the cancellous bone.
• Further, these implants have shallow square threads in the central
third of the implant body, which are easily incorporated in the
already prepared threads in the bone by the apical deep implant
threads.
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32. • These square threads laterally
condense the trabecular bone and
enhance the primary stability of the
implant.
• The crestal part of these implants has
only very shallow micro-rings, which
get easily seated in the osteotomy and
do not exert much pressure on the
high-density and low- vascular crestal
bone. This prevents pressure necrosis
of the bone
32

33. Root form implants classified on the basis of the
crestal polished collar
Subgingival (two-stage) implants
⮚These are widely used implants and their all part of the fixture
is placed within the bony envelop of the ridge with their
platform is placed at the level of ridge crest
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34. Transgingival (one-stage) implants
⮚These implants have a long
polished collar and their
plat- form is placed at the
level or above the level of
soft tissue (transgingival
placement)
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35. Root form implants classified on the basis of
implant pieces
Two-piece implants
• Most implants come in two pieces – the fixture is one part
and the other part is the abutment, which is screwed over
the fixture to support the prosthesis
35

36. One-piece implant
• This implant comes with the abutment as an integral part
of the fixture (all in one piece). All called single body
implants.
• These implants are used for immediate functional or non-
functional restoration after implant placement.
• The fabrication of the connection in the implants (with
narrow diameters below 3.3 mm) is difficult and can
weaken the implant body.
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37. ⮚Initially a few companies started manufacturing these
implants in the narrow diameters from 2.5–3 mm for use
in tight spaces (e.g. the mandibular incisors and maxillary
laterals), and to retain dentures in geriatric patients with
narrow edentulous ridges.
⮚These implants were also termed ‘mini implants’ because
of their small size.
⮚Later, these single-piece implants were manufactured in
the regular to wider diameters, for use in cases where
adequate bone volume and density was available to place
and immediately restore these implants
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38. 38

39. Implant surfaces
39

40. ⮚Dental implants with different surface treatments are
available in the market, and their manufacturers claim that
they are superior to the conventional machined surface
titanium implants for predictable quality of
osseointegration.
⮚As a general rule, roughened surfaces increase the bone–
implant contact (BIC) percentage during the initial bone
healing process.
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41. ⮚Several research studies have been performed to find an
optimal surface treatment to increase mechanical stability and
improve the contact between bone and implant.
⮚Many research projects have provided conclusive scientific
evidence that a roughened titanium implant surface improves
bone anchoring compared to conventionally machined titanium
surfaces.
⮚The rough surface facilitates migration of osteogenic cells to
the implant surface for de novo bone formation (contact
osteogenesis).
⮚The local mechanical environment provided by the rough
surface implant also influences cellular differentiation and
tissue synthesis (distance osteogenesis).
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42. • The local mechanical environment provided by the rough
surface implant shows increased removal forces, greater
BIC percentage, earlier bone– implant contact , and
improved ultimate osseointegration.
• The ‘osseointegration’ phenomenon was first described
by Branemark and associates and was defined as the
direct contact between living bone and a functionally-
loaded implant surface without interposed soft tissue at
the light microscope level.
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43. • Titanium is the metal widely used for dental implant
manufacturing, either in the commercially pure titanium form
(cpTi) or as an alloy, because it shows a variety of favourable
features like high strength, low weight, high corrosion
resistance, low modulus of elasticity, and easy shaping and
finishing capability.
• The titanium alloy (titanium-6 aluminium-4 vanadium [Ti 6
AI 4 V]) most frequently used for implant manufacturing is
composed of 90% titanium, 6% aluminium (decreases the
specific weight and improves the elastic modulus) and 4%
vanadium (decreases thermal conductivity and increases
hardness).
43

44. ⮚An implant made of pure titanium or titanium alloy,
when exposed to the air, immediately forms an
‘oxide layer’ (titanium dioxide [TiO 2 ]) over its
surface.
⮚This layer comes in contact with the bony tissue
and plays an important role in corrosion resistance,
biocompatibility and osseointegration.
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45. ⮚ The chemical composition of the implant surface can differ markedly from its
bulk composition due to manufacturing processes, such as machining,
thermal treatment, blasting, etching, coatings, and even sterilization
procedures.
⮚ Surface contamination introduced by these procedures (e.g. traces of metals,
ions, lubricants, and detergents), may alter surface biocompatibility for better
or worse, even when it is present in small quantities.
⮚ Based on these considerations, careful control of the composition of the
implant surface becomes a relevant procedure to produce high quality
implants.
❑The following are a few of the most commonly used implant
surfaces:
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46. Machined/smooth/turned implant surface
• It was the most commonly used surface in the past;
however, it is not now very commonly used, because of
improved stabilization and larger surface area obtained in
roughened surface implants.
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47. Modified implant surface
⮚Conventional machine implant surfaces can be modified
with either ‘additive methods’ (e.g. hydroxyapatite
coating, plasma spraying, etc.) or ‘subtractive methods’
(e.g. acid-etching, sandblasting, etc.), to improve the
implant surface and its characteristics, to achieve optimal
implant osseointegration with the jawbone.
47

48. Sandblasted surface
• Titanium metal implants are sandblasted, using agents such as
aluminium oxide/alumina (Al 2 O 3 ), titanium dioxide (TiO 2 ), and
calcium phosphate to increase surface roughness.
• The sandblasting not only improves BIC percentage, but also
improves contact osteogenesis by allowing the addition,
proliferation, and differentiation of the osteoblasts over the implant
surface.
• The few disadvantages of the sandblasting procedure are the
presence of sandblasting material residues on the implant
surface, non-uniform surface treatment, and loss of metallic
substance from the implant body.
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49. • A specific method to produce calcium phosphate-blasted
implants is also used. The titanium base is submitted to
blasting with calcium phosphate, a resorbable blast
material (RBM), followed by a passivity procedure to
remove the residual calcium phosphate (CaPO 4 ) and it
is finally, cleaned.
• The blast medium is resorbed during these processes,
and a surface of pure TiO 2 is produced that is free of
contaminants (e.g. PTS™/ OsseoFix™ surface of Adin
implants).
49

50. Titanium plasma sprayed (TPS) surface
• These implants are prepared by spraying molten metal on
the titanium base, which results in a surface with
irregularly sized and shaped valleys, pores, and crevices,
increasing the microscopic surface area by approximately
10 times.
• One disadvantage of using these implants is the
possibility of detachment of titanium after implant insertion
(e.g. TPS surface of Friadent implants).
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51. Acid-etched surface
⮚Acid-etching of titanium implants is performed using baths
of hydrochloric acid (HCL), nitric acid (HNO 3), and
sulphuric acid (H 2 SO 4 ) in specific combinations.
⮚A dual acid-etched technique is also being used by a few
manufacturers to produce a microtextured implant surface
which improves the BIC percentage as well as the reverse
torque value of the implant. (e.g. Osseotite surface of 3i
implants.)
51

52. Sandblasted and acid-etched surface
• A few implant manufacturers have started creating this surface
by first sandblasting to produce macrotexture, followed by
acid-etching to produced a final microtextured surface.
• This surface shows promising results, as these implants have
shown high BIC percentage as well as reverse torque value.
• Other advantages of this surface are higher rate and degree of
osseointegration, better osteoconductive properties, and
higher capability to induce cell proliferation.
52

53. • Many studies and clinical trials have claimed that these
implants, if inserted in bone with adequate volume and
density, can be restored after 6 weeks.
• In a few clinical situations, after consideration of other
parameters, these implants can immediately be loaded
(e.g. SLA surface of Straumann implants, FRIADENT®
plus surface of ANKYLOS® implants, SLA surface of
Alpha Bio implants, etc.)
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54. Anodized surface
• This surface is prepared by applying voltage on titanium
implants immersed in an electrolyte, which results in a
surface with variable diameter micropores.
• The advantages of this surface are improved cell
proliferation and attachment, lack of cytotoxicity, and
more removal torque value in the implant (e.g. TiUnite
surface of Nobel Bio- care implants).
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55. Hydroxyapatite (HA) coated surface
• Hydroxyapatite coated implants have shown roughness
and functional surface area similar to TPS implants.
• This surface shows accelerated interfacial bone formation
and maturation; hence, the direct bonding between the
HA coating and the bone is found to be far superior to the
bond between titanium and bone or TPS and bone.
• An initial implant-to-bone interface contact is essential for
a predictable interface to form.
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56. • The space or gap between the implant and bone may affect
the BIC percentage after healing. Gap healing can be
enhanced by the HA coating.
• The HA coating also reduces the corrosion rate of the metal
(e.g. the HA coated surface of Biohorizons D4 implants).
• Some advantages of HA coated implants are increased
roughness and surface area, enhanced initial implant stability,
increased gap healing between bone and HA coating, less
corrosion of metal, faster healing at the bone interface, and
stronger bone–implant interface.
56

57. • The disadvantages of HA coating are flaking, cracking or
scaling of the coating at implant insertion (especially in
high-density bone), increased plaque retention when left
exposed to the oral environment or resulted after the
crestal bone resorption and marginal soft tissue
recession.
• Coating also increases the cost of the implant. Many
studies and clinical trials have shown higher success
rates for HA coated implants used in low-density (D4)
bone.
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