Dental Implants in Health Flashcards
Which prosthetic is better than natural teeth?
Nothing!
What is the “best” alternative to teeth?
Implants
Osseointegration definition
Direct attachment/connection with vital osseous tissue (bone) to implant surface without CT
What is an osseointegrated implant comparable to?
Ankylosed tooth
T/F - 100% bone connection is possible
False - 60% is good enough
How can you increase the amount of osseointegration?
Make a rough/porous surface (surface characteristics) - better for cancellous bone
Surgical manipulation of bone
How can you surgically manipulate alveolar bone?
Anatomical location
Augmentation techniques (bone grafts)
Condensation
How does the posterior maxilla compare to the anterior mandible
Post max = lots of trabecular (low density)
Ant man = lots of compact bone (more dense)
How do we measure osseointegration?
It’s a histological finding
Based on bone:implant surface attachment
What are components of reliable osseointegration
Biocompatability of the implant
Design of implant (we want it root-shaped)
Surface conditions of implant (rough > smooth)
Host bed (bone)
Loading conditions (healthier = quicker loading speed)
What are the steps of implant placement?
1) Incision - cut soft tissue
2) Mucoperiosteal flap elevation (lift)
3) Prep bed in cortical/spongy bone (osteoctomy - drill bone)
4) Insert titanium device
The highest success implants are placed where?
Root sulcus
What can effect initial implant stability
Lateral displacement of bone tissue at cortical bone level
From bone quality
Surgical trauma
How does trabecular bone help implant stability?
Necessary to keep bone vital by providing blood supply
Surgical trauma effect
Initiates wound healing
We want the implant to ankylose with bone AND establish mucosal attachment
Bone healing after 24 hours
Cortical bone resorption
Woven bone formation
Blood clots
Vasculature forms in newly formed granulation tissue
Bone healing after 1 week
Have reparative macrophage/undifferentiated mesenchymal stem cells
Remodiling in apical trabecular bone region, at the threads of the screws
Where is the most resorption/remodeling of bone?
At the tips of the threads of the screws
Bone healing after 2 weeks
First detectable signs of new bone at the “furcation sites” of the implants
Bone healing up to 6 weeks
Callus formation (slight shrinkage)
AND
lamellar compaction within woven bone
This temporarily decreases primary stability, but it can recover
Bone healing after 6 weeks
Plateau effect of implant stability and enhanced bone formation around the implant
Jumping distance definition
Distance that can be filled by new bone formation
-between the implant and surrounding alveolar bone
What is the ideal tolerable jumping distance
20-40 um
Anything greater than 40 um will not heal well
What is the accepted ealing period for osseointegration?
Maxilla = 6 months Mandible = 3 months
What are the 4 theories of loading
Immediate loading
Early loading
Late loading
Progressive loading
Immediate loading
Load as soon as implants are placed
Early loading
Before 6 months
Late loading
Wait 6 months
Progressive loading
Start early, but with a smaller load and sequentially increase the load
What does it mean that bone can functionally adapt?
Responds to change in loading via remodeling of internal structure
Helps achieve optimal biomechanical situaiton as long as forces aren’t excessive
What type of bone do we want to integrate an implant into?
We want a balance of cortical and trabecular bone
Between 2 and 3 on that chart
How can we modify bone quality?
Different surgical techniques and instrumentation
What is the ideal surface characteristics of an implant?
Rough
- TPS (Titanium Plasma spray)
- SLA (sand-blasted, large grit, acid etched)
- Coated: HA or TCP (tri-calcium phosphate) - these aren’t used much - great initially, but coating may wear leading to gaps
Titanium-allow implant characteristics
Covered with titanium dioxide - increases biocompatibility
Will increase in thickness over time
Increased porosity leading to increased surface area which means better osseointegration
Surface irregularity to increase osseointegration
What is the ideal location of implant placement?
Follow the Cingulum line
What happens if the implant is placed too buccally?
Screw will shoot through - look dark like an amalgam tattoo
What happens if the implant is placed too lingual?
Act as a cantilever - leading to tons of bone resorption and eventually failure
What can we do if there is insufficient bone for bone collar?
Use guided bone regeneration
What is the minimum thickness of alveolar bone needed to surround implant?
1mm
What is the minimum bone thickness needed between 2 implants?
3mm
What is the minimum bone thickness needed between and implant and a tooth?
4 mm
The coronal part of an implant should be placed where/
~5mm apical to the adjacent CEJ
T/F - Maximum parallelism between implants and teeth is mildly important
False - it is critical!
- want only vertical occlusal forces along the long axis
- Maximum of a 20’ angle (but Kumar said 30’)
What are the layers for trans-mucosal attachment?
Barrier epithelium
CT Zone
Barrier epithelium
2mm long
Scar tissue agter placing implant - thinner epithelium around the implant
CT Zone
1-1.5 mm high
Fibrous
Collagen fiber bundles are parallel to implant surface but do not attach to the implant
What are the components for the soft-tissue/mucosal component of osseointegration
Need trans-mucosal attachment
Soft-tissue adjacent to implant surface
Soft-tissue lateral to “adjacent zone”
Soft-tissue adjacent to implant surface
Lots of fibroblasts
Few blood vessels
Soft-tisse lateral to “adjacent zone”
Fewer fibroblasts than adjacent to implant surface
Further away from implant surface
Only blood vessel supply is via supraperiosteal blood vessels (none form PDL)
Less blood for host/immune cells
What are the different Implant placement techniques?
2-stage implant placement
1-stage implant placement
2-stage implant placement
Place fixture and cover with a soft-tissue flap
Load after healing
1-stage implant placement
Place fixture and add temporary abutment immediately with no cover
Immediate loading can be done
Only do this in patients with better prognosis
Micro-gap
Micro space between implant and abutment
Normally at the alveolar crest
Biologic width in dental implants
Exists around both unloaded and loaded implants
Should be 3mm
What are clinical parameters of Peri-implant health?
No mobility
No bone loss ≥ 0.2mm in the first year - must use radiographic exam
No pain, complaints, or infections
Must be functionally and esthetically acceptable to both patient and doctor
What is the implant success rate after 5 and 10 years?
5 yrs = 94-98%
10 yrs = 90-94%
What are the 3 techniques to evaluate implants?
Peri-implant probing
Check for mobility
Radiographs
Do all 3 simultaneously
Resonance Frequency Analysis
A way to measure osseointegration
Resonsnce frequency of an object correlated to boundary constrains of a structure (aka how well its stuck in place)
Other factors to measure peri-implant health
Keratinized tissue or attached gingiva is required around implants
Success rate of implants placed after grafted sites - very similar to sites with pristine bone
