Week 4 Tulio: Replacement of missing teeth Flashcards
Describe conformational changes in alveolar bone after tooth extraction
- Collapse of cortical bone wall especially buccal side composed mainly of bundle bone.
- Sensible diminishing in blood perfusion from PDL affects survival of cortical bone (cortical bone doesn’t have much blood supply so when PDL + tooth is removed, there is redued angiogensis and blood perfusion)
- Wound healing contraction
- Bundle bone disappear after 2 weeks and is gradually replaced by woven bone (Phase I)
- Phase 2 included resorption that occurred from the outer surfaces of both bone walls
What is bundle bone?
Histologic name for alveolar bone that provides attachment to PDL fibres
What is D1-D4 classification and what does it mean?
- D1: more cortical, less cancellous (stronger but less nutrients for healing)- md symphysis
- D2: ideal for implants
- D3: ideal for implants
- D4: less cortical, more cancellous (weaker but more nutrients for healing)- posterior mx
What can you do if the required space for teeth is greater than the space present?
- Interproximal stripping
- Distalisation
- Arch expansion
- If difference less than 2mm can ask lab to make implants smaller
What is seiberts classification of alveolar bone changes after exo?
What type of implant bridge should be avoided?
Avoid cantilever toward distal
What tx’s have been proposed over the years to treat bone defects?
Guided tissue regeneration
Guided bone regeneration
Tissue engineering
What bone has more cortical bone?
B of mandible
What is the issue with reduced cancellous bone?
Reduced regenerative capacity (less blood vessels and cells)
Why is this case difficult for implant placement?
- Type 1 cortical bone
- Guided bone regeneration is possible but difficult
- Need to know anatomy
What are the steps of implant tx plan?
- CC
- Pt interview
- Examination
- Diagnostic (casts, imaging, photos, surgical template)
- Quote and consent
- Treatment
- Maintenance
What is the issue with placing implant in this case?
Crowns are spaced far apart but roots converge towards each other. Distance available for implant screw is reduced.
What factors influence implant success?
- Implant based (implant length/diameter, number, brand and bone augmentation)
- Prosthesis based (type of reconstruction, type of edentulism, loading time)
- Surgeon based (operator training)
- Patient based (pts condition, compliance)
Why shouldn’t you place bridge using implant and teeth as abutments?
Micromovement of tooth due to PDL. Crown can decement → caries
