Implant Planning & Placement Flashcards
What is osseointegration?
Direct functional and structural connection between a load bearing dental implant & living (organised) bone
What are the 2 stages of osseointegration?
Primary osseointegration = implant anchored in bone due to frictional forces provided between osteotomy & dental implant design features
Secondary osseointegration = process of a functional connection between bone & a dental implant, living bone grows onto the surface of a dental implant
How does healing occur after implant insertion?
- begins immediately after implant installation
- granulation tissue in wound chamber (days)
- immature [woven bone] (weeks)
- Mature lamelar bone (months)
How does the supra-crestal soft tissue of a tooth present?
- more fibroblasts
- less collagen
- collagen fibres orientated perpendicular to root surface
How does the supra-crestal soft tissue of an implant present?
- more collagen
- less fibroblasts
- collagen fibres orientated parallel to implant crown
How does the sub-crestal soft tissue of a tooth present?
- tooth anchored to bone by periodontal complex
- capable of physiologic adaptation
- resilient tissue attachment
How does the sub-crestal soft tissue of an implant present?
- implant anchored to bone by direct functional contact
- no physiologic adaptation present
- rigid connection
What dental materials are used in dental implants?
- titanium (Ti)
- titanium zirconium (Ti-Zr)
- ceramic implant (Y-TZP)
How do implants differ from teeth in function?
- no proprioception from implant
- no physiological adaptation
What type of titanium is used in implants?
Commercially pure TYPE 4 TITANIUM
- >85% to produce titanium dioxide
How do titanium-zirconium implants differ from titanium implants?
Increased strength compared to Ti
- good in narrow implant sites where less bone available
What determines implant design?
- bone level/tissue level
- tapered/parallel
When might tapered implants be advantageous?
- provide increased primary stability in immediate placement [eg post XLA site]
- may be used where there is root convergence apically
What determines length/diameter of implant selection?
- site of implant
- indication of implant
- local anatomy
What is considered a ‘smooth’ implant?
0-0.5um
What is considered a ‘mild’ roughness implant?
0.5-1um
What is considered a ‘moderate’ roughness implant?
1-2um
What is considered a ‘rough’ implant?
> 2um
What surface treatment can be done to implants to roughen them?
- sand blasting
- acid etch
- plasma spray
What is the purpose of a dental implant?
Restore
- functionality
- aesthetics
- psychology
What medications may affect the survival or success of a dental implant?
- SSRIs
- PPIs
- bisphosphonates
- steroids
What medical conditions may contraindicate implant placement?
- pts undergoing radiotherapy
- poorly controlled diabetes
- CV disease
What social history findings may contraindicate implant placement?
Smoking
- increased risk of implant failure
- increased risk of peri-implantitis
Why does smoking have a negative impact on implant healing?
Smoking affects
- vascularity
- fibroblast/osteoblast function
- PMN function
What areas of dental history would you investigate when considering implant placement?
- pt attendance
- motivation
- self performed plaque control
- suitable for surgical procedure
- presence of parafunctional habits
Why should implants only be placed when patient growth has stopped?
If implants placed before growth complete:
- relative infra-occlusion
- suboptimal aesthetics
- occlusal disharmony
- implant fenestration
What is defined as a high smile line?
> 2mm ST on show
What is defined as a medium smile line?
<2mm of ST showing
What is defined as a low smile line?
lip covers >25% of teeth
What extra-oral findings may affect implant placement decisions?
- presence of incisal cants
- presence of gingival cants
- width of aesthetic zone
What are the different gingival phenotypes?
- thick flat
- thick scalloped
- thin scalloped
What issues are associated with implant placement when edentulous span is too wide?
- challenge to fill place
- issues with where to leave residual space
What issues are associated with implant placement when edentulous span is too narrow?
- risk of damage to adjacent teeth
- risk of necrosis of bone between teeth & implants
- will have significant effect of ST aesthetics
How is available bone assessed for implant placement?
Assess
- volume
- orientation
What relevant maxillary local anatomy may be relevant when considering implant placement?
- maxillary sinus
- nasal floor
- naso palatine canal
- infra-orbital nerve
What relevant mandible local anatomy may be relevant when considering implant placement?
- inferior alveolar canal
- mental foramen
- incisive canal
- lingual perforating vessels
- submandibular fossa
What gingival phenotype has the best aesthetic results from implant placement?
- thick biotype
- rectangular teeth
When looking at 3D implant positioning, what needs to be considered?
Mesio-distal positioning & orientation
Bucco-palatal positioning & orientation
Apico-coronal positioning
What does 3D implant positioning depend on?
- implant system being used
- proposed gingival margin
- local anatomy
- prosthetic plan
Why should implants be positioned a “safe” margin away from adjacent teeth?
- lowers risk of damage to adjacent teeth
- lower risk of bone necrosis and ST defect between implants and teeth
What is the minimum mesio-distal distance required from other teeth/implants for implant placement?
1.5mm
What is the required bone amount that should be present labially for implant placement?
> 1mm of bone labially
What are the different placement protocol types that can be done during implant placement?
What aids to implant planning are needed?
- study models
- diagnostic wax up
- surgical template
- essex
- clinical photographs
- CBCT
- surgical guide
How can implant placement be planned before committing to procedure?
- diagnostic wax ups
- combined with CBCT
