Implants

Question 1

Pros and cons of increased thread depth on implants (e.g. Nobel Active)

Answer 1

Advantages:
- increased primary stability
- longer the distance coils protrude from the implant, the more surface and load distribution

Disadvantages:
- may reduce insertion accuracy

Question 2

tapered vs. cylindrical implant design

Answer 2

Advantages:
- Tapered implants have higher primary stability, because they distribute forces more equally and exert lateral compressive forces on the cortical bone. (This does not make sense to me.)
- May help avoid apical fenestrations or injury to anatomical structures

Disadvantages:
- Tapered implants may require a more invasive surgical approach to prepare the implant site and ensure proper placement

Question 3

Would there be a benefit to grafting the implant with gray show-through?

Answer 3

Generally, phenotype conversion by means of CTG is

Question 4

Factors that could have led to implant failure for this patient?

Answer 4

• blood supply (maxilla): multiple surgeries
• low bone availability
• poor surgical positioning
• possible early loading / off-axis loading?

Question 5

Why did you take out implant #26?

Answer 5

discussed keeping the implant
- locator for removable
- connecting it to the other teeth (risky)
- bury under FPD – couldn’t bury, because the cover screw and part of implant were protruding through the tissue; pt had periimplantitis around this implant (6-7mm probing depths, purulence) and were concerned with ability to perform hygiene under the FPD once this was decided upon

Question 6

Risks of splinting implant to teeth

Answer 6

1) overloading the implant - screw loosening, screw fracture, implant fracture, bone resorption
2) intrustion of teeth - more likely if periodontally compromised; to prevent this, it is recommended to use stress-breakers (female end on implant and male end on pontic)

Question 7

What are some reasons you might splint an implant to a tooth?

Answer 7

1) systemic or local issues that preclude placement of additional implants
2) implant needs the support of the natural teeth (e.g. implant is needed for occlusal guidance in a bruxir)
3) esthetics (e.g. maintaining mobile teeth in esthetic zone that might otherwise be lost by splinting them to implants)