implant Flashcards
(90 cards)
1
Q
What are the characteristics of the ideal tooth replacement? (5 characteristics)
A
- FIRM
- Does not destroy adjacent teeth
- Preserve alveolar bone
- Sensate
- Easy to clean
2
Q
characteristics of ideal tooth replacement
A
firm does not destroy adjacent teeth preserve alveolar bone easy to clean sensate
3
Q
alternatives for tooth replacement
A
tissue supported dentures
tooth supported bridge
implant supported crown
4
Q
what are the pros and cons of using tissue supported denture for tooth replacement
A
easy to clean
does not preserve alveolar bone
5
Q
pros and cons of implant
A
pros:
- achieve excellent aesthetics
- does not involve preparation adjacent teeth
- preserve residual bone
cons:
- expensive
- require surgery
- technically complex
- time consuming
6
Q
condition needed for bone to be maintained
A
stress must be conducted to osteons/osteocytes
compressive stress will cause bone resorption
7
Q
What are the historical types of dental implants? (6 types, acronym TrollMEMES)
A
- Transmandibular implant
- Mucosal insert
- Endodontic Implant (Stabilizer)
- Mini implant (temporary, transitional)
- Endosteal/Endosseous implant (Blade/root-form implant)
- Supraperiosteal implant
8
Q
What are the pros of implants?
A
- Do not involve preparation of adjacent teeth
- Preserve residual bone
- Excellent aesthetics
9
Q
what are the downsides of supraperiosteal implant
A
framework sits on top of periosteum, exerting pressure that causes bone resorption
10
Q
What are the principles of implantation
A
Bone is the only tissue that regenerates
All other tissues repair with scar tissue except during fetal period
11
Q
What are the conditions needed to allow bone to regenerate fully?
A
Needs to have certain stresses on the osteons and osteocytes to detect that the bone is being used if not the bone will atrophy
Thus, edentulous patients, bone resorb
Compressive stresses also cause bone resorption (force is too much, not physiologic, bone will resorb)
12
Q
What are the historical types of dental implants? (6 types, acronym TrollMEMES)
A
- Transmandibular implant
- Mucosal insert
- Endodontic Implant (Stabilizer)
- Mini implant (temporary, transitional)
- Endosteal/Endosseous implant (Blade/root-form implant)
- Supraperiosteal implant
13
Q
What is a mucosal insert implant
A
Tiny buttons in the denture, corresponding attachment button implanted ONLY in mucosa
- NOT FIRM, moves
- Does not maintain bone
14
Q
What is an endodontic implant? (stabilizer)
A
After root canal treatment, place this implant through the root canal and apex into the bone- cause very difficult extraction
Purpose is to stabilise and preserve remaining natural teeth
15
Q
What is a supraperiosteal implant?
A
Raise flap, take impression, cast CoCr framework that sits on top of periosteum, with tiny attachments that go through the mucosa to attach denture
16
Q
What is a blade implant?
A
Use fissure bur to make groove, use mallet to knock implant into the bone
17
Q
What is a transmandibular implant?
A
1 implant from mouth, 1 from chin through the mandible
18
Q
What is the definition of a dental implant?
A
PERMUCOSAL device which is BIOCOMPATIBLE and BIOFUNCTIONAL and is placed within bone which retains prosthesis (fixed or removable)
Mad of various biomaterial (commonly titanium- gold standard)
19
Q
Why use titanium in implants?
A
Osseointegration- serendipitous finding by Dr Branemark
- Direct contact between bone and implant surface
- Bone healed directly on titanium cylinder surface without intervening fibrous tissue
20
Q
What is an alloplastic material?
A
Material not from the patient’s body (synthetic)
21
Q
Definition of osseointegration?
A
(1) TIME DEPENDENT
(2) HEALING PROCESS
where by clinically asymptomatic
(3) RIGID FIXATION
of alloplastic materials is achieved, and maintained, in bone during
(4) FUNCTIONAL LOADING
(Zarb and Albrektson, 1991)
Basically ANKYLOSIS
22
Q
What are the advantages of multicomponent implant compared to single piece implant?
A
greater retrievability in the situation of failure (e.g. if crown fractures, can just remove that part and replace, fixture is usually fine)
23
Q
Why do people not use HA coatings on implants anymore?
A
Hydroxyapetite coating has been shown to break loose or even dissolve after a few years
24
Q
Why are surface treated implants preferred to machine polished implants?
A
Roughened surface allows bone to grow in better, due to increased surface area of the titanium implant
25
Is the whole implant roughened to aid in osseointegration?
NO, transmucosal attachment has to be smooth to reduce plaque formation and biofilm adhesion
26
What are the parts of the implant?
1. Implant body-fixture
2. Abutment
3. Prosthetic
27
What are the advantages of multicomponent implant compared to single piece implant?
greater retrievability in the situation of failure (e.g. if crown fractures, can just remove that part and replace)
28
easiest location to place implant and why
upper premolar
no nerve and sinus nearby
29
what are the downsides of mucosal insert implant (attachments used to retain denture)
not firm
| does not preserve bone
30
what are the downsides of endodontic implant
make extraction difficult
31
what are the downsides of supraperiosteal implant
framework sits on top of periosteum, exerting pressure that causes bone resorption
32
what is a dental implant
permucosal device that is biocompatible and biofunctional that is placed within mucosa or on or within bone associated with the oral cavity to provide support for fixed or removable prosthesis
33
what is osseointegration
direct contact between bone and implant surface
time dependent healing process whereby clinically asymptomatic rigid fixation of alloplastic material is achieved and maintained in bone during functional loading
direct connection between living bone and load bearing endosseous implant at light microscopic level via direct bone apposition to implant surface
34
When do you use angulated abutments as opposed to straight axis abutments?
When there is some complication in the placement of the implant fixture in bone, where the angulation of the fixture is not corresponding to the intended prosthesis long axis. (Surgeon cock eye and drill wrongly)
35
What are the steps of the surgical procedure of implant placement? (4 main steps)
1. Initial surgery
2. Osseointegration period
3. Abutment connection
4. Final prosthetic restoration
36
benefits of threaded implant vs non threaded
threaded implant demonstrate maintenance of clear steady state bone response
enhances initial stability and increase surface contact
37
main benefit of multicomponent implant over single piece implant
retrievability
38
What are 4 factors that influence osseointegration?
1. Biocompatible material
2. Implant adapted to prepared site
3. Atraumatic surgery
4. Undisturbed healing phase
39
How would you describe the soft-tissue to implant interface of a SUCCESSFUL implant
Unbroken, perimucosal seal between soft tissue and implant abutment surface
40
What are the similarities and differences in soft-tissue connection to implants and natural teeth
Similarity: epithelium attaches to surface of titanium and enamel through a basal lamina and formation of hemidesmosomes
Difference: natural tooth- sharpies fibers extend from bundle bone of lamina dura and insert into the cementum of tooth root surface. Implant- no sharpies fibers, no PDL, no cementum or fiber insertion. ONLY LONG JUNCTIONAL EPITHELIUM
41
How does the difference in soft-tissue connection to implants affect the management and care of implants
Easy for periimplantitis to progress very quickly, because only long junctional epithelium is present
42
What is pitch?
Number of threads per unit length. Increased pitch on top part of abutment to grip more of cortical bone, make implant more stable. Decreased pitch to allow cancellous bone to adapt to it
43
What bone quality is usually found in the anterior lower jaw?
Quality I- HOMOGENOUS COMPACT BONE
44
What bone quality is the most favourable for implant placement
Quality II, usually found in posterior lower jaw. Thick layer of cortical bone surrounding dense trabecular bone
45
Why is quality I bone not the best for implant placement?
It is so dense, that when you drill, the bone may overheat
46
Why is quality I bone not the best for implant placement?
It is so dense, that when you drill, the bone may overheat
47
main benefit of multicomponent implant over single piece implant
retrievability
48
location with greater success rate for osteointegration
interforamina area where bone is very thick and dnse
49
What temperature must bone be kept below
45 degrees
50
How do you ensure bone does not overheat?
Use NEW SHARP DRILLS
Use graded series of drills, do not just put in the biggest size and force it in
Proper drill geometry, and intermittent drilling
51
What happens if your insertion torque is too high?
Result in stress concentrations around implant, microfractures, subsequent bone resorption
52
What is one-stage surgical protocol for delayed loading?
Preferred method, sufficient insertion torque, implant is stable immediately
53
When is immediate loading done?
Aesthetic anterior teeth
54
What is two-stage surgical protocol for delayed loading?
Place in implant, close up, three months later you go back in
Put in bone graft also two-stage
55
What are complications of off-axis loading
Bone resorption, or implant fracture
56
What is success rate of osseointegration in type I bone?
97%. Highest success in type I (anterior mandible) Lowest success in posterior maxilla
57
What is the course of action in failed osseointegration
Take out implant, let it heal and put in again
58
What can you do to manage the complication of altered sensation and nerve injury?
Mandibular implants- risk of injury to IDN posterior to mental foramen
1. Proper imaging- DPT has magnification, CBCT most accurate in measurement of distance
2. Take measures to ensure magnification is correct
3. Knowledge of anatomy and instruments
4. Informed consent
59
What are the various causes of infection and bone loss related to implant failure?
1. Post-op infection, placement of foreign body into bone close to oral environment
2. Perio disease (peri implantitis)
3. Placement of bone graft/immediate implants into area of existing active infection
4. Exposure of rough surface of implant to oral environment, rapid deterioration because of increased biofilm accumulation
60
What are the maxillary sinus complications related to implants
1. Penetration of sinus by implant- nothing happens unless percolation of oral fluid in max sinus
2. Placement in thin maxillary bone without bone graft, implant can loosen and drift into sinus
3. Sinus lift- tears in membrane leading to acute sinusitis
61
What happens if implant is angulated wrongly
1. Injury to adjacent teeth
2. Lead to off axis loading
3. Unrestorable- need to have procedure to remove it, or leave it and let it be buried
62
What can cause fractures of implant/components?
1. Excessive insertion torque during placement
2. Excessive cantilever
3. Poor implant selection and loading causes stress in excess of material property of titanium
63
Aside from the IDN and maxillary sinus, what other anatomical structures can be perforated by implants?
1. Lingual pouch (arteries)
2. Nasal cavity
3. posterior superior alveolar artery
4. Pterygoid implants - pterygoid venous plexus
5. Zygomatic implants- orbital floor and contents
64
What happens if implant is angulated wrongly
1. Injury to adjacent teeth
2. Lead to off axis loading
3. Unrestorable- need to have procedure to remove it, or leave it and let it be buried
65
What are the factors affecting implant survival (SIMPP)
```
Surgeon- skill, experience
Implant design, surface modification
Maintenance
Prosthodontic- loading of resto
Patient- local factors, systemic factors, habits
```
66
What are the patient local factors that affect implant survival
1. Bone quality- density
2. Bone quantity- vertical, buccal lingual, length of time since tooth loss, infection/cyst
3. Location- anatomical structures
4. Soft tissue- more keratinised gingiva, easier to brush
5. Oral hygiene, active perio disease
67
What are the patient systemic factors that affect implant survival
1. Immune suppression- diabetes, smokers, previous allotransplantation, immunosuppression therapy
2. Previous drug exposure to bisphosphonates- MRONJ
3. Previous radiation therapy (ORN)
68
What are the patient habits that affect implant survival
1. Smokers
2. Bruxism
3. Grinding/clenching
4. Occupation- dangerous/active occupations (commando)
5. Age - too young (below 18) alveolar bone still growing, infraoccluded implant
too old- cannot cooperate, multiple medical problems
69
what are the anatomic considerations when placing implant
```
ridge relationship
inter arch clearance
attached tissue
inferior alveolar nerve
maxillary sinus
floor of nose
```
70
complications of placing implant
```
failure of osseointegration
altered sensation and nerve injury
infection and bone loss
maxillary sinus complications
aesthetic failure
fracture of implant and components
perforation of anatomical structures
wrong implant angulaton
```
71
what are the types of bone healing
osteogenesis
osteoconductive
osteoinductive
72
what is osteogenesis bone healing
viable osteoblasts/osteocytes present, direct healing and formation of new bone and blood vessels
73
what is osteoinductive bone healing
organic material induce differentiation of osteoblasts from osteoprogenitor cells
74
what is osteoconductive bone healing
inorganic material provide scaffolding, conduct path for osteoclasts to resorb HA and osteoblasts to form new osteons
75
what are the types of bone graft
autogenous
allogenous-human ie donor (provide scaffold for body to replace with own bone)
xenogenous
alloplastic (synthetic)
76
why is it important for bone graft to be fixed in place
micro motions can disrupt angiogenesis. loss of blood supply cause bone graft to fail
77
alternative techniques to graft bone for implant
fixation with bone screws or titanium mesh
alveolar sandwich osteotomy
distraction osteogenesis
78
what are the osteoactive agents that can be used for bone graft
osteoinducers eg rhBMP but very expensive
osteoproomters
stem cells and tissue engineering
79
what are the local sources of bone harvest
```
maxillary tuberosity
maxilla
mandible
ramus
menton
adjacent bone bone scrapings
bone from drills
```
80
what are the regional sources of bone harvest
```
calvarial parietal bone
iliac crest
rib
free flap
tibial
```
81
downsides of iliac crest anterior and posterior as a source for bone harvest
anterior: risk of peritonitis, retroabdominal hemorrhage, scar on side of hip
posterior: scar on backside
82
what regional source of bone harvest can be harvested from under LA
Tibial (30cc of bone)
83
how much vertical height can you gain with alveolar sandwich osteotomy vs alveolar distraction
alveolar sandwich osteotomy: up to 5mm
| alveolar distraction: 12mm
84
what are the types of sinus lift
internal lift (summer's osteotome)
external lift
85
what type of sinus lift is safer
external lift is safer as it allows for direct visualisation (but increased dissecting results in more swelling)
86
what are the risks of sinus lift
membrane tear exposing bone graft to infection
acute maxillary sinusitis
spread of sinusitis to the cranial cavity
diseased maxillary sinus --risk of sinusitis
87
what are the types of computer aided surgery
template based surgery
image guided surgery/navigational surgery
88
soft tissue grafting techniques for implant
free gingiva graft
free subepithelial connective tissue graft
pedicled graft
acellular dermal or mucosal matrix
89
what are regenerative implants
polycaprolactone (PCL) which is a 3D printed polymer with pores for osteoblasts to go inside
larger defects require PCL to be paired with BMP or platelet rich plasma to enhance healing
90
what are some of the newer materials to generate bone for implant
```
regenerative implants
PCL-TCP scaffold
sugars eg heparan sulfate act as ligand for different growth factors
msc exosomes
tissue engineered scaffolds
```
