Surgical Aspects of implants - planning and placement Flashcards
What are the key points to consider regarding the pt with implants?
- Priorities - functional (to bite on) /fixed/aesthetic
- Smile line
- What is the pt like? - expectations, understanding?
- Understand risks and timescale?
Do not assume that implants are the only option that may satisfy patients expectations - discuss bridge/denture/gap
What medications/medical conditions to be wary of with implants?
Bisphosphonates = BRONJ risk
Diabetes = poorly controlled = increased risk of failure
Immunosuppressants = poorer healing response
Steroids = increased risk of bone problems and worse healing
Bone disease - osteoporosis/pagets = difficult to remove bone as very dense = overheat it = necrosis
Radiotherapy = Could cause osteoradionecrosis (if less than 65 rays decreased risk of osteoradionecrosis)
Bleeding tendency
What is the only absolute contraindication to implants?
IV bisphosphonates / denosumab
Social history’s impact on implant success?
20-300% increase in failure risk
Healthy non-smoker approx 3% failure
= Max risk is 9% failure
Heavy smoking >15 a day
Not absolute contraindication but is absolute contraindication to providing on NHS
Clinical examination for implants?
EO
- Facial profile - skeletal pattern - jaw shape
- Smile line = baseline for assessing aesthetic risk
IO
- Space requirements; horizontal and vertical
- Access
- Periodontal status
- 3D assessment of available bone
What makes a pt v high risk for osteonecrosis of the jaw?
Steroids and bisphosphonates
High smile line?
Upper lip line is above cervical line = aesthetic issues visible e.g. recession
Medium smile line?
Cervical line not exposed, but papillary line visible
Low smile line?
Upper line line cover’s papillary line
= No gingiva shown = aesthetic concerns hidden under lip = warn pt of this
Class III skeletal and occlusal pattern - why is this an issue with implants?
Square jaw = implants placed far forward could affect the nerve
Horizontal space requirements for implants?
Horizontal:
- Minimum 3mm between implants
- Minimum 1.5mm between implant and tooth
- Smaller space between tooth and implant as tooth will have a good blood supply via the PDL but implants do not have a PDL so need space for the blood vessels to prevent bone necrosis and gingival recession
- 1.5mm-2mm of bone needed mesially and distally, buccally/lingually from the implant screw
- Implants are about 4mm in dimensions and 7mm width needed for implant so 1.5mm either side of bone (if back of mirror handle fits in gap it should be ok)
Vertical space requirements for implants?
Screw retained restoration 5mm
Cement retained restoration 7.5mm
Minimum 15-17mm height for milled bar
How to find out if you have enough space for access for implants and endo?
If you can fit 2 fingers between top and bottom tooth you have enough space
What to check with the periodontal status? Why is this important?
Bleeding on probing
Pathological pocketing
Review previous CPITN/evidence of recession
History of periodontitis increases risk of peri-implantitis
Active disease contraindicates implant placement
Bone dimensions
Mesiodistal = clinical space and surgical space
- Can you fit a crown between the teeth e.g. if tilting
- Position of tooth roots e..g if move away from each other apically = favourable
= Issue with ortho e.g. space maintenance for missing lateral = torque the roots so they are in correct position
Buccolingual = most critical defining factor for whether implant is feasible in anterior zone
- Can palpate to see how thick bone feels, ridge map, get CBCT to assess buccolingual dimension
Vertical
