Osseointegration Flashcards
A direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant:
Osseointegration
Six key factors for successful implant osseointegration:
- BIOCOMPATIBILITY of the implant material
- Macroscopic & microscopic nature of the IMPLANT SURFACE
- The status of the implant bed in both a HEALTH (non-infected) & a MORPHOLOGIC (bone quality) context
- the surgical TECHNIQUE
- The undisturbed HEALING PHASE
- The subsequent PROSTHETIC DESIGN and the long LOADING PHASE
CP:
commercially pure
Why do we use CP titanium and titanium alloys: (5)
- low weight, high strength/weight ratio
- low modulus of elasticity
- excellent corrosion resistance
- excellent biocompatability
- easy shaping and finishing
What is the most frequently used titanium alloy for implants?
Titanium-6 Aluminum-4 Vanadium
List the composition of Titanium-6 Aluminum-4 Vanadium:
-90% Titanium
-6% Aluminum
-4% Vanadium
What does the 6% aluminum in Titanium-6 Aluminum-4 Vanadium contribute?
Decreases the specific weight & improves the elastic modulus
What does the 4% Vanadium in Titanium-6 Aluminum-4 Vanadium contribute?
Decreases thermal conductivity and increases the hardness
Tenacious oxides in air or oxygenated solution:
titanium oxide layer
The titanium oxide layer promotes:
adhesion of osteogenic cells
Surfaces topography influences:
osteoblasts morphology
List the different categories of surface topography: (4)
- smooth
- minimally rough
- moderately rough
- rough
According to the study ____ & ___ surfaces showed weaker bone response than with _____ surfaces
Smooth & minimally rough; rough
According to the study, _____ surfaces showed stronger bone response than rough in some studies
moderately rough
surface topography influences bone response at the:
micrometer level
How might we change the surface topography?
physical &/or chemical methods
List some examples of how we can modify the surface:
- machined
- plasma-spray
- titanium-spray
- sand-blasted & acid etched
- RBM (resorbable blast media with calcium phosphate)
- zirconia ceramic
- hydroxyapatite coatings
- lasers
- nano-structured surfaces
Surface treatment that includes etching with strong acids to increase the surface roughness and surface area of titanium implants:
acid etched
Surface treatment that includes an electrochemical process to thicken and roughen the titanium oxide layer on the surface of implants:
anodized
Surface treatment that includes particles being projected through a nozzle at a high velocity onto the implant.
Can be done with various materials such as titanium dioxide, aluminum dioxide and hydroxyapatite (HA)
Blasted
Surface treatment that includes implants undergoing a blasting process and afterwards the surface is either washed with non-etching acid or etched with strong acids:
blasted & acid-washed/etched
Surface treatment that includes an osteoconductive material that has the ability to form a strong bond between the bone and the implant:
Hydroxyapatite (HA)
Surface treatment that includes high-intensity pulses of a laser beam strike to a protective layer that coats the metallic surface. As a result the implants demonstrate a honeycomb pattern with small pores:
Laser ablation
Surface treatment that includes powdery forms of titanium that are injected into a plasma torch at elevated temperatures:
Plasma-sprayed
A greater surface roughness increase the potential for:
biomechanical interlocking
Rougher implant surfaces have a higher percentage of ______ and also a higher _______ than machined surfaces
bone implant contact; torque removal
The chemical composition of bone is _____ % inorganic and ___% organic
70% inorganic
30% organic
What comprises the inorganic component of bone?
Crystalline salts (primarily HA)
What comprises the organic component of bone?
- Type I collagen (90-95%)
- non-collagenous proteins
- proteoglycans
- growth factors
What cells can be found in bone?
- pre-osteoblast
- osteoblast
- osteoclast
- osteocytes
- monocytes
- macrophages
- endothelial cells
Active osteoblasts deposit:
osteoid matrix
The 3 Davis’ basic concepts:
- bone is synthesized by only one cell- osteoblast
- bone grows only by apposition
- bone matrix mineralizes and has no inherent capacity to grow
De novo bone formation that occurs on the surfaces of old bone in the peri-implant site:
Distance osteogenesis
In DISTANCE osteogenesis the bone surfaces provide a population of ____ that lay down a new matrix that encroaches on the implant
Osteogenic cells
In ______ osteogenesis, new bone is NOT forming on the implant, but the latter does become surrounded by bone
Distance
Results in bone approximating the implant:
Distance osteogenesis
No bone is present on the surface of the implant upon implantation:
Contact osteogenesis
In CONTACT osteogenesis, new bone forms first on the _______ and has to become colonized by _____ before bone matrix formation can begin
implant surface; bone cells
Bone is formed for the first time at the appropriate site by differentiating osteogenic cells:
Contact osteogenesis
Results in bone apposition to the implant surface:
Contact osteogenesis
Results in bone approximating the implant:
Results in bone apposition to the implant surface:
Distance osteogenesis
Contact osteogenesis
Two hours after implant installation- the threads are in contact with the bone leading to:
mechanical anchorage
Two hours after implant installation- the primary stability is through:
mechanical stability
Two hours after implant installation- the void between the pitch and the body of the implant can be described as:
a well defined wound chamber
Two hours after implant installation- the blood clot is characterized by:
- erythrocytes
- neutrophils
- monocytes/macrophages in a network of fibrin
- leukocytes
Two hours after implant installation- the blood clot characterized by erythrocytes, neutrophils, monocytes/macrophages in a network of fibrin + leukocytes are engaged in:
wound cleaning process
Following implant installation the blood clot is replaced with _____ four days after
primitive granulation tissue
The primitive granulation tissue that replaces the blood clot four days after implant installation contains:
- mesenchymal cells
- matrix components
- newly formed vascular structures
The primitive granulation tissue that replaces the blood clot four days after implant installation contains mesenchymal cells, matrix component and newly formed vascular structures which is evidence of:
angiogenesis
In the early events of osseointegration the _____ has been established
provisional connective tissue matrix
What type of surface is characterized by the following events:
Four days after implant installation, in the proximal region, an early granulation tissue has formed, whilst the region close to the device, large numbers of erythrocytes remain:
rough surface
What type of surface is characterized by the following events:
Four days after implant installation, in the area close to the parent bone, the clot has been penetrated by vascular structures surrounded by fibroblast-like cells, whereas in the areas close to the surface of the device, large numbers of erythrocytes, polymorphonuclear leukocytes and macrophages remain:
Machined surface
Osseointegration: bone remodeling at 1 week-
____ in the wound chambers are rich in vascular structures and mesenchymal cells
Provisional connective tissues
Osseointegration: bone remodeling at 1 week-
A relatively small number of _____ was still present
inflammatory cells
Osseointegration: bone remodeling at 1 week-
A ____ was seen in the provisional CT that surrounded the blood vessels
Cell-rich immature bone (woven bone)
Osseointegration: bone remodeling at 1 week-
____ occurred in the center of the chamber as well as discrete locations that apparently were in direct contact with the surface of the titanium device: “____”
woven bone formation; contact osteogenesis
Osseointegration: bone remodeling at 1 week-
_____ was not observed on polished implant surfaces at this stage
contact osteogenesis
According to the human bone model, healing period was:
6 weeks
The original Branemark’s protocol recommended strict adherence to surgical and prosthodontic technique and a “non-disturbed” healing period of:
3-6 months
What follows the original Branemarks protocol of a non-disturbed healing period of 3-6 months?
An abutment and superstructure prosthesis are fabricated and attached to the implant fixture
Today clinicians have three loading options which include:
- immediate loading
- early loading
- delayed loading
Loading technique in which the prosthesis is connected to the implant fixture within the first 48 hours:
immediate loading
Loading technique in which the prosthesis is connected to the implant fixture after the first 48 hours but prior to 3 months:
early loading
Loading technique in which the prosthesis is connected to the implant fixture after the initial three months:
delayed loading
Immediate loading time:
Early loading time:
Delayed loading time:
within 48 hours
after 48 hours to 3 months
after three months
T/F: According to the study immediate implant loading may impose a greater risk for implant failure when compared to conventional loading although the survival rates were high for both groups
true
By connecting the implants with _____ we limit the micro-movements and therefore ensure the osteointegration process
acrylic restoration
What is the ideal insertion torque for immediate loading?
Greater than 35 Ncm
Osteotomy can be prepared using: (3)
- sequential drilling
- blunt osteotome
- piezosurgery
What was the most beneficial form of osteotomy preparation?
Piezosurgery (leaves a cleaner cavity for implant placement with very few osseous debris)
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
The insertion torque is measured in:
Ncm (newton centimeters)
According to the study, is there an optimal insertion torque for osseointegration to occur around unloaded implants?
No significant differences were observed in the way bone heals around implants placed at high vs. low insertion torque
