Principles Of Implant Surgery Flashcards
Planning Implant surgery
What are 6 things to consider when planning implant surgery?
1) site anatomy - assess through:
- clinical examination
- radiographs/ CBCT
2) Site volume and shape
3) Implant size and spacing
– What size should be used and where?
4) Emergence profile of crown
5) Position of screw holes
6) Emergence position of crowns (nature of soft tissue)
May need to consider Grafting
Consider tooth will be placed as there may be bone loss/remodelling folllowing tooth extraction
Consider aesthetics and surgical aspects
Below image shows CBCT used to plan for implant surgery- can draft surgery on computer:
Grafting
When might it be necessary in implant surgery
Why is the nature of soft tissue important
Hard tissue or soft tissue grafting
To optimise hard tissue aspect or nature of soft tissues where the implant is going to be placed
Nature of soft tissue is important because in absence of keratinised tissue harder to keep implant clean and therefore longer term complications
For understanding, not to learn - might want to do bone grafting etc so that the implant is more stable/has enough bone support once you place it - thus would do if bone volume was low for eg
Restorative pre surgical planning
1 - What can be used for restorative pre surgical planning?
2 - What are provisional restorations that could be used prior to surgery?
3 - what can digital dentistry do?
4 - what do provisional restorations and digital dentistry allow?
1 -
We can use Provisional restorations or Digital Dentistry for restorative pre surgical planning
2 -
1) Use existing dentures, sometimes with radio-opaque markers
2)Wax up and make an Essix device with denture or temporary teeth
3) Maryland adhesive bridges, in composite
3-
Digital dentistry
Allows for Scanning and Planning:
• Scan bone – CBCT
• Scan ridge
• Scan provisional restoration
• Use in silico design transferred to intra oral try in
– combine all of these
4 -
These allow
patient discussion, approval, trial wear and adjustment , assessment of proposed tooth position, aesthetics, function and relationship to underlying bone
Implant / Bone surfaced area
How much bone should be all around aspects of each implant ?
1-1.5mm
How much space should be between adjacent implants?
3mm
What Sizes and shapes to use
When drilling bone what 2 things must be considered?
Tissue level implants vs Bone level implants
What are the benefits of wider implants?
Wider implant = stronger implant
So reduced risk of fracturing or cracking
EG below 5mm implant is stronger than the 3mm on the left
Therefore would probably use for different teeth eg - 5mm for lower molar, 3mm for lower incisor
Implant length
1 - Benefits of longer implants ?
2 - Are longer implants better than shorter implants?
1 - longer implants = more bone contact (bone to implant surface area) = more load spread
2 - NO, previously used to believe it is better to place a long as possible implant due to above reasons however there are scenarios where shorter implants are preferred:
- shorter implants are easier to remove with fewer complications if implant fails
- shorter implants are just as strong as longer implants
- anatomical - if you want to place a tooth near maxillary antrum EG UR6
- shorter implants have same level of survival as longer implants (but fail earlier )
However shorter implants are more likely to be lost than longer - as if bone loss around implant, then will be greater chance of loss at an earlier point of time
(There are sinus lifts - bone grafting materials placed to life floor of maxillary sinus + allow a longer implant to be placed but has risks)
Extra short implants
Don’t know if need to know this slide
These are different to short implants - they are EXTRA SHORT
Had some issues but important to remember only 3% of cases - supporting idea that longer isn’t necessarily a lot better
Writing meant to say peri implant mucotitis - look at graph
Soft tissue at implant site: Do you need keratinised tissue around implant / abutment / restoration emergence?
What happens if there is insufficient keratinised tissue around implant?
(Keratinised tissue = band of tissue surrounding teeth (just for understanding ))
YES
If patients have less than 2mm keratinised tissue:
LINGUALLY - higher risk of lingual plaque accumulation, inflammation + bleeding
BUCCALLY - higher risk of recession
Eventually Loss of attachment will occur resulting in failure of dental implant - peri implantitis
Peri implantitis:
If patient has a lack of keratinised tissue around implant, what can be done?
Free gingival graft - Consider soft tissue grafting surgery if the band of keratinised tissue is narrow
Tissue is taken from somewhere else in the mouth and attached
This leads to improvement in soft tissue profile
(No difference in probing depths in these pts - showing it is recession NOT pocketing )
Preoperative
What must you tell the patient before implant surgery>
Surgical principles
Sterility
Single use instruments / drills
Soft tissue access
How do we get soft tissue access?
Surrounding and underlying anatomy
Site preparation / drilling / osteotomy
What is osteotomy?
2 - what drilling technique is used during osteotomy during implant surgery and what speed is the drill set at ?
3 - why that type of drilling ?
1 - surgical procedure involving cutting bone (just for understanding )
2 - Incremental drilling
1500-1800 rpm
Using single use drills
3 - incremental drilling (going from narrow drill, then using one size bigger each time) so that:
- there’s minimal trauma to bone
- surgeon can adjust angulation of drill to ensure implant has correct angulation
The drilling used in implant surgery can cause bone to overheat, what is done to counter this?
Cooling - Copious sterile saline, pumped via drill unit
Ideally are single use or multi use drills used?
Single use drills are the gold standard
However multi use drills can be used but need to be audited
Primary stability
What does primary stability of an implant mean?
Once implant is placed, whether the implant is stable within the site
How is primary stability achieved in implants ?
How much narrower is the final drill than the implant width in implant surgery
0.3-0.5 mm
What is mechanical retention in implants determined by?
Determined by:
1. density of the bone
– varies between sites and patients - assess during preparation
- surgical technique
– underprepare site - drill slightly narrower than the implant placed there - implant design
– thread pitch and implant macroshape
What is the degree of primary stability of an implant determined by?
Torque settings
This is how tight the implant has been screwed into the recipient bone site
What are the 2 methods of implant surgery?
1) original / conventional implant surgery (2 stage procedure)
2) single stage conventional
Loading and restoration protocols – original / conventional
What are the stages in original/conventional implant surgery?
- Pre op planning
- Extractions/ other surgery (3-6 months)
- Stage 1 surgery - place and bury implants (3-6 month wait)
- Stage 2 surgery - expose implants
- Place healing abutment (1-2 months)
- Final abutment and take impressions
- Temporary restoration (2-9 months)
- Definitive restoration
- Maintenance
What are the 2 stages in the two - stage procedure in original/conventional implant surgery?
Healing abutments
What are healing abutments used for?
Help promote soft tissue healing
There are a range of shapes based on the final restoration that will be placed on top
Loading and restoration protocols – single stage conventional
Stages in single stage conventional?
For understanding -an implant impression coping is a temporary abutment that is attached to the implant post or abutment while the final restoration is being fabricated
Give the full detailed steps in how an implant is placed into the dentitions
What are the two needs for implant placement
Surrounding bone and keratinised tissue
What does good primary stability help with
osseointegration
Summary
