Osseointegration Flashcards
“A direct structural and functional connection between ordered,
living bone and the surface of a load-carrying implant”
Osseointegration
What are the 6 key factors for successful implant osseointegration?
- Biocompatibility of the Implant material
- Macroscopic and microscopic nature of the implant surface
- The status of the implant bed in both a health (non-infected)
and a morphologic (bone quality) context - The surgical technique
- The undisturbed healing phase
- The subsequent prosthetic design and long term loading phase
- Low weight high strength/weight ratio
- Low modulus of elasticity,
- Excellent corrosion resistance
- Excellent biocompatibility
- Easy shaping and finishing.
Titanium
____ (decreases the specific weight and improves the elastic
modulus)
- 6% aluminum
______: (decreases thermal conductivity and increases the
hardness).
- 4% vanadium
: tenacious oxides in air or oxygenated
solutions - Promotes adhesion of osteogenic cells
TITANIUM OXYDE LAYER
Should smooth, rough, or moderately rough implant surfaces best for osseointegration?
Moderately rough
In order for osseointegration to occur, do you want the surface area to be increased or decreased?
Increased SA
A _____ surface roughness
increases the potential for
biomechanical interlocking
greater
______ implants surfaces have an higher percentage
of bone implant contact and also an higher torque
removal than machined surfaces.
Rougher
What percentage of bone is inorganic?
65-70%
What percentage of bone is organic?
30-35%
Type 1 collagen
First, bone matrix is synthesized by only one cell: the ______.
osteoblast
Second, as a result of the polarized synthetic (meaning the
synthesis of bone matrix) activity of osteoblasts, bone
grows only by _____.
apposition
Third, bone matrix _______ and has no inherent capacity
to “grow.”
mineralizes
• de novo bone formation occurs on the surfaces of old
bone in the peri-implant site.
• The bone surfaces provide a population of osteogenic
cells that lay down a new matrix that encroaches on the
implant.
• New bone is not forming on the implant, but the latter
does become surrounded by bone.
• Results in bone approximating the implant
Distance osteogenesis
No bone is present on the surface of the implant upon
implantation
New bone forms first on the implant surface Implant surface
has to become colonized by bone cells before bone matrix
formation can begin
Bone is formed for the first time at the appropriate site by
differentiating osteogenic cells.
surface.
• Results in bone apposition to the implant surface
Contact osteogenesis
(Osseointegration timeline)
• Threads are in contact with bone - Mechanical anchorage
• Primary mechanical Stability
• The void between the pitch and the body of the implant: a well
defined wound chamber
• Blood clot characterized by : erythrocytes, neutrophils and
monocytes/macrophages in a network of fibrin + leukocytes
engaged in the wound cleaning process
• Blood cloth replaced with primitive granulation tissue 4 days
after : this tissue contained mesenchymal cells, matrix
components and newly formed vascular structures (i.e evidence
of angiogenesis)
• Provisional CT matrix had been established
2 HOURS AFTER IMPLANT INSTALLATION
(Osseointegration timeline)
Rough : In the proximal region an early granulation
tissue has formed, whilst in the region close to the
device, large numbers of erythrocytes remain
MACHINED: In the area close to the parent bone the
clot has been penetrated by vascular structures
surrounded by fibroblast-like cells, whereas in the area
close to the surface of the device, large numbers of
erythrocytes, polymorphonuclear leukocytes and
macrophages remain.
4 days
(Osseointegration timeline)
• Provisional CT in the wound chambers rich in vascular structures and mesenchymal cells.
• A relatively small number of inflammatory cells was still present.
• A cell-rich immature bone (i.e. woven bone) was seen in the provisional CT that surrounded the blood vessels.
• Woven bone formation occurred in the center of the chamber as well as in discrete locations that apparently were in direct contact with the surface of the titanium device : “Contact Osteogenesis”
• Contact osteogenesis was not observed on polished implant surfaces at this stage
1 week
(Osseointegration timeline)
Woven bone formation was more pronounced in all compartment
• Woven bone were noticed in the bone marrow regions ‘apical’ of the implant. This osteogenesis took place at a distance from the implant surface and hence was termed ‘distant osteogenesis’.
• In many regions woven bone was bridging to the surface of the implant.
• At this time point of healing, most of the implant surface was occupied by newly formed bone, which formed a continuous coat on the implant surface (i.e. ‘osteocoating’).
• Osteoclast formation noticed on the pristine bone surfaces, resulting in bone resorption adjacent to the implant surface, especially in areas of pressure of the implant to the bony bed (i.e. pitches of the threads).
• After 2 weeks of healing: Mechanical stability replaced by Biological bonding and stability.
2 weekls
(Osseointegration timeline)
Continuous cell-rich ‘osteocoating’ covered most of the titanium wall of the chamber.
• The central portion of the chamber was filled with a primary spongiosa, rich in vascular structures and contains a multitude of mesenchymal cells.
4 weeks
(Osseointegration timeline)
Most of the wound chambers were now filled with mineralized bone.
• Bone tissue consisted of primary and secondary osteons
• Mature bone tissue contact with the implant surface to a very high extent.
• Bone marrow containing blood vessels, adipocytes and mesenchymal cells was observed to surround the trabeculae of mineralized bone.
• The bone trabeculae had become reinforced by lamellar or parallel-fiber bone deposition, thus providing a structure to cope with the bearing of load.
6-12 weeks
_______ loading – prosthesis connected to the implant fixture within the first 48hrs.
Immediate loading
______ loading – prosthesis is connected to the implant fixture ater the first 48hrs but prior to 3 months.
Early loading
______ loading – prosthesis connected to the implant fixture ater the iniral 3 months.
Delayed loading
Is immediate loading better for single crowns or larger restorations?
Larger restorations
______ (surgical technique) leaves a cleaner cavity for implant placement, with very few osseous debris.
Piezosurgery
The ________ can be defined as the measurement of the resistance that the
implant encounters during its advancement in the apical direction by means of a
rotating movement on its axis
insertion torque
