Biological considerations of dental implant

1. Dr. Firas Kassab

2. • Implant introduction
• Implant classification
• Implant geometry ( Macro design)
• Endosseous implants
• Subperiosteal implants
• Transmandibular implants
• Implant surface characteristics ( micro design)
• Additive processes
• Subtractive processes
• Hard tissue interface
• Stages of bone healing and ossointegration
• Soft tissue interface
Dr. Firas Kassab

3. Dr. Firas Kassab

4. Implant :- Any object or material , such as an alloplastic substance
or other tissue, which is partially or completely inserted or
grafted into the body for therapeutic , diagnostic, prosthetic or
experimental purposes.
Dental implant :- A prosthetic device of alloplastic material
Implanted into the oral the oral tissues beneath the mucosa,
periosteal layer and or within the bone to provide retention and
support for a removal or fixed prosthesis.
Dr. Firas Kassab

5. Implantology :- The study or science of placing and restoring
dental implants.
Implant surgery :- The phase of implant dentistry concerning the
selection, planning, and placement of the implant body and
abutment.
Implant prosthodontics :- The phase of prosthodontics concerning
the replacement of missing teeth and/or associated structures
by restorations that are attached to dental implants
Dr. Firas Kassab

6. Implant dentistry:- The selection, planning, development,
placement, and maintenance of restoration(s) using dental
implants.
Implant abutment :- The portion of the dental implant that serves
to support and or retain any prosthesis.
Implant prosthesis:- Dental prosthesis such as crown and other
fixed dental prostheses, removable dental prostheses as well as
maxillofacial prostheses supported and retained in part or
whole by dental implants.
Dr. Firas Kassab

7. 1.Based on implant design
2.Based on attachment mechanism
3.Based on macroscopic body design
4.Based on the surface of the implant
5.Based on the type of the material
Dr. Firas Kassab

8. Dr. Firas Kassab

9. • Endosseous implants
• blade like
• Pins
• Cylindrical (hollow and solid)
• Disklike
• Screw shaped
• Tapered and screw shaped
• Subperiosteal framelike implants
• Transmandibular implants
Dr. Firas Kassab

10. • Inserted into the jaw bone after mucoperiosteal flap elevation.
• Tapped in place in a narrow trench made with a rotary bur.
• One or more posts pierced through the mucoperiosteum after
suturing of the flaps.
• After a few week healing, a FPD is fabricated by a classic
method and cemented on top of it.
Dr. Firas Kassab

11. Dr. Firas Kassab

12. • Three diverging pins were inserted either transgingivally or
after reflection of mucoperiosteal flaps in holes drilled by spiral
drills.
• At the point of convergence, the pins were interconnected with
cement to ensure the proper stability because of their
divergence.
Dr. Firas Kassab

13. • Hollow and
• Full cylindrical
• Straumann and co workers introduced hollow cylinders in mid1970s.
• Implant stability would benefit from the large bone to implant surfaces
provided by means of the hollow geometry.
• Holes ( vents ) favour the ingrowth of bone to offer additional fixation.
Dr. Firas Kassab

14. • Full cylindrical implants were used by Kirsch and became
available under the name of IMZ .
• The long term survival rates were unacceptable, leading to the
limited use of this implant type currently.
Dr. Firas Kassab

15. • They are rarely used at present.
• The concept was developed by Scortecci. It is based on the
lateral introduction into the jaw bone of a pin with a disk on
top.
• Once introduced into the bone volume, the implant has strong
retention against extraction forces.
Dr. Firas Kassab

16. • The most common type of implant is the screw shaped, threaded
implant.
• A decrease in the interthread distance at the coronal end of the
implant has been proposed to enhance the marginal bone level
adaptation.
Dr. Firas Kassab

17. 1. Minimize apical bone fenestration
2. Allow for implant placement in narrow
apical sites
3. Amenable to immediate placement into
anterior extraction socket
Dr. Firas Kassab

18. • They are customized according to plaster model derived from
an impression of the exposed jawbone, prior to the surgery
planned for implant insertion.
• They are designed to
retain the overdenture.
• They are rarely used.
Dr. Firas Kassab

19. ENDOSTEAL
BLADE
RAMUS FRAME
ROOT FORM
Dr. Firas Kassab

20. Dr. Firas Kassab

21. • They were developed to retain the dentures in the edentulous
lower jaw.
• The implant was applied through submandibular skin incision.
• “staple bone” implant
developed by Small,
consisted of a splint
adapted to the
lower border
of the mandible.
Dr. Firas Kassab

22. Dr. Firas Kassab

23. Dr. Firas Kassab

24. Cylindrical Implant
Threaded implants
Plateau implantsPerforated implants
Solid implant
Vented
implant
Hollow
implant
Dr. Firas Kassab

25. Dr. Firas Kassab

26. Dr. Firas Kassab

27. • Biomechanics involved in Implantology includes
The nature of the biting
forces on the implants
Transferring of the biting
forces to the interfacial
surfaces
The interfacial tissue
reaction
Dr. Firas Kassab

28. • A successfully osseointegrated implant provides a direct and
relatively rigid connection of the implant to the bone.
• A critical aspect affecting the success or failure of an implant is
the manner in which mechanical stresses are transferred from
the implant to bone smoothly.
Dr. Firas Kassab

29. • Surface plays an important role in biological interactions.
• Surface modifications have been applied to metallic
biomaterials in order to improve the
• Mechanical
• Chemical
• Physical
• such as
• Wear resistance
• Corrosion resistance
• Biocompatibility and surface energy, etc.
Dr. Firas Kassab

30. • Micro rough surfaces
• Better bone apposition
• Higher percentage of bone in contact with the implant
• Influence the mechanical properties of the interface
• Stress distribution
• Bone remodelling
• Smooth surfaces
• Bone resorption
• Fibrous connective tissue layer
Dr. Firas Kassab

31. • Surface coatings
• Carbon, glass, ceramic
coating
• Hydroxyapatite coating
• Ca –P coating
• Composite coating
• Titanium Nitride coating
• Titanium plasma spray
coating
• Titania film coating
Additive
Dr. Firas Kassab

32. Increase the
functional surface
of implant-bone
interface
Effective stress
transfer
Promote bone
apposition
Improved
osseointegration
Dr. Firas Kassab

33. • The surface of titanium has been modified by ion beam mixing
a thin carbon film.
• The corrosion resistance and other surface and biological
properties were enhanced using carbon plasma immersion ion
implantation and deposition.
• Reactive plasma spray produces a feasible BAG-coating for Ti-
6Al-4V dental implants.
• The coating withstands, without any damage , an externally
generated tensile stress of 47MPa,and was adequate for load
bearing applications.
Dr. Firas Kassab

34. • Enhancement of the osteoconductivity of Ti implants is
potentially beneficial to patients since it
• shortens the treatment time and
• Increases the initial stability of the implant
Hydroxyapatite
Tri calcium phosphate
Dr. Firas Kassab

35. • Ca-P coatings are applied to
• To combine the strength of the metals with the bioactivity of Ca-P.
• Accelerates the bone formation around the implant and effectively the
osseointegration rate
• Various technique
• Ion beam dynamic mixing technique(IBDM)
• Radio frequency magnetron sputter
• Biometric
• Deposition
• Electrochemical deposition
• Plasma spraying
Dr. Firas Kassab

36. • BioActive Ca-P
• Phosphate based glass
• Hydroxy apatite
• TCP – tri calcium phosphate
• CPP – calcium pyrophosphate
• The cells on the coatings expressed higher alkaline phosphatase
activity than pure Ti.
• Suggesting the stimulation of the osteoblastic activity on the coatings.
Dr. Firas Kassab

37. • Titanium nitride is known for its high surface hardness and
mechanical strength.
• Increasing the corrosion resistance &surface hardness of the implant
surfaces exposed
• Titanium nitriding - various methods
• Gas nitriding
• Plasma nitriding by plasma diffusion treatment
• Plasma assisted chemical vapour deposition
• Pulsed DC reactive magnetron sputtering
• Closed field unbalanced magnetron sputtering ion plating
Dr. Firas Kassab

38. • Favour the osseointegration of the bone because of the inherent
roughness of such coating
Dr. Firas Kassab

39. • An ion beam assisted sputtering deposition technique has been
used to deposit thick and dense TiO2 films on titanium surfaces
which are not easily breached and hence improved corrosion
protection.
Dr. Firas Kassab

40. • Sand blasting
• Shot peening
and LASER
peening
• Dual acid
etched
technique
Subtractive
Dr. Firas Kassab

41. Cleaning surface
contaminants to prior to
further operation
Roughening surfaces to
increase effective/functional
surface area
Producing beneficial surface
compressive residual stress
Dr. Firas Kassab

42. • Alumina (Al2O3)
• Silica ( SiO2)
Dr. Firas Kassab

43. • Similar to sand blasting but has more controlled peening power,
intensity, and direction.
• It is a cold process in which the surface of a part is bombarded
with small spherical media called shot.
Dr. Firas Kassab

44. • The LASER peening technology is recently developed
• Non contact
• No media
• Contamination free peening method
Dr. Firas Kassab

45. • High intensity (5 -15GW/cm2)nano second (10-30ns) of LASER
light beam (3-5mm width)striking the ablative layer generate a
short lived plasma which causes a shock wave to travel into the
implant.
• The shock waves induces the compressive residual stress that
penetrates beneath the surface and strengthens the implant,
resulting in improvement in fatigue life and retarding the stress
corrosion cracking occurrence.
Dr. Firas Kassab

46. • Dual acid etched technique
• To produce microtexture rather than macrotexture
• Enhance the osteoconductive process through the attachment of fibrin and
osteogenic cells, resulting in bone formation directly on the surface of the
implant.
• Higher adhesion and expression of platelet and extracellular genes, which
help in colonization of osteoblasts at the site and promote
osseointegration.
Dr. Firas Kassab

47. • Sandblasted and acid etched (SLA) method
• SLA given by BUSER et al,
• Sand blasted, large grit, acid etched.
• The surface is produced by large grit blasting process followed by acid
etching using hydrochloric acid.
Dr. Firas Kassab

48. Dr. Firas Kassab

49. Dr. Firas Kassab

50. Vs
Dr. Firas Kassab

51. Stages of bone healing and osseointegration
Dr. Firas Kassab

52. A, Three-dimensional diagram of the tissue and titanium
interrelationship showing an overall view of the intact interfacial
zone around the osseointegrated implant.
B, Physiologic evolution of the biology of the interface over time.
Dr. Firas Kassab

53. • The term Osseointegration was first used by Prof I-P
Branemark. since then it has been used to describe the
procedure of bone attachment with titanium. Though lately, the
Glossary of Prosthetic Terms (Sixth Edition) lists the terms
Osseointegration and osteointegration but recommends the use
of the term osseous integration.
Dr. Firas Kassab

54. • Osseointegration was originally defined as, a direct structural
and functional connection between ordered living bone and the
surface of a load-carrying implant.
• Branemark in 1985
• A direct on light microscopical level, contact between living
bone and implant.
• Albrektsson in 1981
• A bony attachment with resistance to shear and tensile forces.
• Steinemann in 1986
Dr. Firas Kassab

55. • Branemark in 1990, then gave a modified definition of his own
–
• “A continuing structural and functional coexistence, possibly in a symbolic
manner, between differentiated, adequately remodeling, biologic tissues
and strictly defined and controlled synthetic components providing lasting
specific clinical functions without initiating rejection mechanism.”
Dr. Firas Kassab

56. • Defined as direct bone deposition on the implant surface.
• Characterized by structural and functional connection between
ordered, living bone and the surface of a load-bearing
implant.
• Compared to as direct fracture healing, in which the fragment
ends become united by bone, without intermediate fibrous tissue
or fibrocartilage formation.
Dr. Firas Kassab

57. Material and
surface
properties
Primary
stability and
adequate load
Dr. Firas Kassab

58. • Material and surface properties
• Bio inert materials
• Titanium
• Rough surfaces
• Improve adhesive strength
• Favors bone deposition
• Degree of mechanical interlock
• Primary stability and adequate load
• Requires perfect stability
• Exact adaptation and compression of the fragments
Dr. Firas Kassab

59. incorporation by woven bone formation;
• 4 to 6 weeks
adaptation of bone mass to load (lamellar
and parallel-fibered bone deposition); and
Second month
adaptation of bone structure to load (bone
remodeling).
Third month
Dr. Firas Kassab

60. • The first bone tissue formed is woven bone.
• characterized by a random, felt-like orientation of its collagen
fibrils, numerous, irregularly shaped osteocytes and, at the
beginning, a relatively low mineral density.
• it grows by forming a scaffold of rods and plates and thus is
able to spread out into the surrounding tissue at a relatively
rapid rate
Dr. Firas Kassab

61. • (deposition of parallel-fibered and lamellar bone)
• lamellar bone, or towards an equally important but less known
modification called parallel- fibered bone
• Three surfaces qualified for deposition of fibered and lamellar bone
• Woven bone formed in the first period of OG
• Pre-existing or pristine bone surface
• The implant surface
Dr. Firas Kassab

62. • Woven bone
• Deposition of more mature bone on the initially formed
scaffold results in reinforcement and often concentrates on the
areas where major forces are transferred from the implant to
the surrounding original bone.
• Pre – existing or pristine bone
• The trabeculae become necrotic due to the temporary
interruption of the blood supply at surgery. Reinforcement by
a coating with new, viable bone compensates for the loss in
bone quality (fatigue), and again may reflect the
preferential strain pattern resulting from functional load.
Dr. Firas Kassab

63. • The implant surface
• Bone deposition in this site increases the bone-impIant
interface and thus enlarges the load-transmitting surface.
Extension of the bone-implant interface and reinforcement of
pre-existing and initially formed bone compartments are
considered to represent an adaptation of the bone mass to
load.
Dr. Firas Kassab

64. • (bone remodeling and modeling)
• Last stage of OG
• It starts around the third month and, after several weeks of
increasingly high activity, slows down again, but continues for
the rest of life.
• Remodeling starts with osteoclastic resorption, followed by
lamellar bone deposition. Resorption and formation are coupled
in space and time.
Dr. Firas Kassab

65. • The cutting cone advances with a speed of about 50 pm per
day, and is followed by a vascular loop, accompanied by
perivascular osteoprogenitor cells.
• Remodeling in the third stage of osseointegration contributes; to
an adaptation of bone structure to load in two ways:
• It improves bone quality by replacing pre-existing, necrotic bone and/or
initially formed, more primitive woven bone with mature, viable lamellar
bone.
• It leads to a functional adaptation of the bone structure to load by
changing the dimension and orientation of the supporting elements.
Dr. Firas Kassab

66. six key factors for successful osseointegration:
• implant material;
• implant design;
• surface quality;
• prosthetic load;
• surgical technique;
• bone health.
Dr. Firas Kassab

67. Dr. Firas Kassab

68. • The healthy soft, keratinized tissues facing teeth and implants
frequently have a pink color and a firm consistency. The two
tissues have several microscopic features in common. The gingiva
as well as the keratinized, peri-implant mucosa is lined by a
well-keratinized oral epithelium that is continuous with a
junctional epithelium that is about 2 mm long.
Dr. Firas Kassab

69. • The interface between epithelial cells and the titanium surface is
characterized by the presence of hemi desmosomes and a
basal lamina.
• Capillary loops in the C/T under the junctional and sulcular
epithelium around implant appear normal
• The thickness of the epithelium is 0.5mm
Dr. Firas Kassab

70. • The average direction of the collagen fiber bundles of the
gingiva is parallel with the implant.
• Even if perpendicular then they are never embedded as in the
case of dentogingival and dentoperiosteal fibers around the
teeth.
• The fiber bundles also have cuff like orientation – soft tissue
seal around the implant.
Dr. Firas Kassab

71. • The vascular supply of the peri implant gingival or oral alveolar
mucosa is more limited than that around natural teeth.
Dr. Firas Kassab

72. Schematic illustration of the blood supply in the connective tissue cuff surrounding the
implant/abutment is scarcer than in the gingival complex around teeth because none
originates from a periodontal ligament.
Dr. Firas Kassab

73. • Newman, Takei, Klokkevold, Carranza. Carranza’s Clinical
Periodontology, 10th Edition and 11th Edition
• Lindhe, Lang, Karring. Clinical Periodontology & Implant
Dentistry, 5th Edition.
• Carle E. Misch. Contemporary Implant Dentistry. 3rd edition.
• PHILLIP’S – SCIENCE OF DENTAL MATERIALS – Kenneth J.
Anusavice , Phd ,DMD
• Robert K, Schenk & Daniel Buser. Osseointegration: A reality.
Perio 2000. Vol 17, 1998, 22-35.
Dr. Firas Kassab

74. Dr. Firas Kassab