Implantology Flashcards
Where is most mechanical stress on implant? Why does this matter?
Crestal 5mm
Width more important than length to minimize stress
Components of Ti allow
90% Ti
6% Aluminum
4% Vanadium
Implant roughness
- Unit of measure
- Average roughness
- Techniques to create roughness
Implant roughness
- Sa value = Unit of measure
- 1-2 Sa = Average roughness
- Techniques to create roughness
- Additive = plasma spray
- Subtractive = Blast or Etch
Given same length and diameter, which has greater surface area?
Straight or Tapered wall implant
Fine pitch or Course pitch
Straight has greater surface area
Fine pitch has greater surface area (more threads)
Restorative distance (crestal bone to occlusal plane)
Min-Max for screw retained
Min-Max for cement retained
Does depth of implant placement affect this?
Restorative distance (crestal bone to occlusal plane)
6-12mm for screw retained
8-12mm for cement retained
Depth of implant placement: sort of matters. If subcrestal there is more room for abutment pieces, porcelain thickness. However, if bony crest to occlusal plan is >12mm than teeth will still look too long and require pink porcelain. And if less than 6mm tooth will look stubby, even if implant deeply subcrestal.
Implant space requirements
- Root
- Other implant
- buccal/lingual plate
- Gingival margin for good emergence profile
- Esthetic zone buccal plate
- Alveolar nerve
- Mental foramen
Implant space requirements
- 1.5mm Root
- 3mm Other implant
- 1mm buccal/lingual plate
- 3mm inferior to Gingival margin for good emergence profile
- 2mm from buccal plate in Esthetic zone
- 2mm Alveolar nerve
- 5mm anterior Mental foramen
Which bone type is mostly cortical bone?
Type 1
Which bone type is best for implant placement?
Type 2
Is magnification in Panorex increased or decreased
Increased
Implant success
Defined as:
Implant success
Defined as:
- Restorable
- <0.2mm bone per year after 1st year of function
- No mobility, radiolucency, symptoms
What temperature causes osseus thermal necrosis
47 celsius
Minimum diameter of keratinized tissue around implant
2mm
Incision design for 2nd stage
- >5mm keratinized buccal
- 4-5mm
- 2-4mm
Incision design for 2nd stage
- >5mm keratinized buccal = Crestal and papilla sparing
- 4-5mm = Crestal, papilla sparing, reverse cutback
- 2-4mm = Crestal, papilla sparing, anterolateral advancement
Which arch has higher failure rate for over denture?
Maxilla
Vertical space for ovedenture
Vertical space for ceramometal
Vertical space for hybrid
Vertical space for ovedenture = 12mm
Vertical space for ceramometal = 8mm
Vertical space for hybrid = 15mm
All on four and zygomatic implants can only be used with which prothesis
Hybrid
Indications for coronally positioned semilunar flap
Where is restorative emergence of zygomatic in relation to original teeth?
Palatal to palatal cusp of premolar
Insertion torque for immediate temporization of implant
30-35ncm
When can free gingival graft be placed in relation to implant placement?
Any of three times
- Original implant placement if non-submerged
- At time of stage II
- Anytime after definitive restoration
Harvest site for free gingival graft
How to prevent neurovascular injury
Smooth area of palate in anterior to 1st molar
How is recepient site prepared for free gingival graft?
Split thickness so graft is secured to periosteal bed
Which has greater shrinkage at gingival graft site
Free gingival graft (Autograft) or Allograft (acellular dermis)
Acellular dermis.
Timing of subepithelial connective tissue graft
Harvest site
Subepithelial connective tissue graft
Timing: completed prior to stage II or done at implant placement if nonsubmerged
Harvested: premolar area 3mm apical to gingival margin. Split thickness leaving behind palatal epithelium
Palatal roll technique
Timing
Harvest site
Palatal roll technique
Timing: only at stage II
Harvest site: subepithelial adjacent palatal tissue
Pedicled palatal flap
Flap classification type
Timing
Random pattern flap
Periosteum/connective tissue
Timing: Done simultaneously with bone graft for large volume alveolar grafts
Match indication with soft tissue procedure
Epithelialized free graft (auto/allograft), subepithelial free graft, palatal roll, pedicled palatal flap
- Deficient width of connective tissue around implant
- Deficient thickness of connective tissue around implant
- Metal show through gingiva
- Large composite defect
- Deficient width of connective tissue around implant = epithelialized graft
- Deficient thickness of connective tissue around implant = subepithelial free graft, palatal roll
- Metal show through gingiva subepithelial free graft, palatal roll
- Large composite defect = pedicled palatal flap
What type of cells are acted on with osteoinduction
Mesenchymal stem cells
Allograft and xenograft
Osteoconductive, osteoinductive, or both
Osteoconductive only. Matrix for host cells
Describe triangle of tissue engineering
Source of cells
Signal
Scaffold
BMP
- Osteoinductive or Osteoconductive
- Belongs to which mesenchymal lineage
- What is source of BMP
- How long should BMP graft heal prior to implant placement
BMP
- Osteoinductive
- Lineage: Transforming Growth Factor (TGF)
- Source: Recombinant human
- 4-6 months of healing
Minimal ridge width for ridge split technique
minimum 3mm
Distraction osteogenesis for ridge augmentation
Latency time
Distraction rate
Consolidation duration
Distraction osteogenesis for ridge augmentation
Latency time = 5-7 days
Distraction rate = 1mm/day
Consolidation duration = 2-3 months
Which dimension of alveolus is most affected in first 6 months after tooth extraction
Buccal lingual 50% reduction in 6 months
Sequence of socket healing with/without graft
Name of stage and duration
Clot with fibrin network = day 1-3
Granulation tissue at crest with provisional matrix = formed by day 7
Epithelial cover and woven bone = month 1
Mature lamellar bone = month 2
Ideal bone graft for socket preservation
Source of bone
Particle size
What is FDA approve and can be used to obtain osteoinduction
Ideal bone graft for socket preservation
Allograft or Xenograft
250-1000micrometer
What is FDA approve and can be used to obtain osteoinduction = BMP
Volume of maxillary sinus in average adult
Sinus dimensions
Thickness of sinus membrane
Volume = 14ml
Sinus dimensions = W2.5cm, H3.75cm, D3cm
Thickness of sinus membrane = 0.1-0.5mm
Alveolar bone thickness for immediate implant placement with sinus lift
3mm
Max elevation of sinus membrane with internal/Summer technique
Uses osteotomes
2mm
Most common surgical complications
Incidence%
Bleeding 25%
Nerve disturbance 7%
Mandible fx 0.3%
Implant failure risk factors
List 6 with incidence %
• Risk factors (failure rate)
– Radiation therapy (maxilla 25%, mandible 6%)
– Maxillary overdentures (19%)
– Type 4 bone (16%)
– Smoking (11%)
– Implants shorter than 10 mm (10%)
– Diabetic patients (9%)
Abutment screw loosening incidence %
More common in single crown, multi-unit PFD, or overdentures
Abutment screw loosening (8%) caused by excursive forces
– Single crowns > multiple-unit “xed prosthesis > overdentures
Peri-implantitis
Present in what % of osseointegrated implants
Normal implant probing depth
Normal bone loss rate
Etiologies x5
Implicated bacteria group
Peri-implantitis
10% osseointegrated implants
<=5mm normal implant probing depth
1.5mm during first year, them 0.2mm per year afterwards
Etiologies x5
- cement
- mechanical (occlusal trauma)
- Bacteria gram-negative anaerobes
- Patient factors: smoking, diabetes, periodontitis
- Surgical factors: bone overheating, poor primary stability, dehiscence
Implicated bacteria group
initial perimplantitis management
Remove etiology
- eliminate overload
- control infection
Management of persistent periimplantitis
3 steps
- Surgical exposure and debridement
- Remove granulation tissue
- Surface decontamination
- Remove biofilm
- Agents: Saline, abrasive pumice, citric acid, chlorhexidine, hydrogen peroxide, tetracycline, lasers
- Guided bone regeneration
- Fill osseous defect and eliminate probing depth
