03 May Splinting or Not Splinting adjacent Implant Crowns? This is the Dilemma
Dr Pasquale Venuti
Splinting or not splinting implants, this is the question.
The premise is that implants and teeth are different beasts:
- Teeth have a ligament….implants not.
- Teeth have a sophisticated proprioception…implants not.
- Teeth have mobility…implants not (except the amount allowed by the bending of the bone under load)
- Teeth can move through the bone (they can migrate orthodontically), implants not.
When we design a fixed prosthesis on natural teeth, we try to avoid splinting abutment for the following reasons:
- giving each abutment the possibility of moving during functions and parafunctions. This freedom decreases the risk of decementation of the prosthesis, decreases the wear damage of the opposing teeth, minimize the overload onto the abutments
- giving the abutments the possibility to change position in the arch (orthodontic movement), minimizing the mechanical stresses. Over time the occlusal conditions may change, and the orthodontic movement of the abutments can improve the stress distribution.
- getting the maximum aesthetics (with connectors it is a bit more difficult to have an appealing aesthetic).
With implants, we do not need to ensure “mobility” and “migrations”…because they cannot happen. Splinting or not splinting, THEY DO NOT MOVE.
Said that, with implants we have to face other kinds of issues:
- screw loosening, more frequent in single implants…..splinted implants reduce this risk
- fracture fracture of implant….splinted implants and abutments are more resistant to chronic overload
- operative problems in managing contact areas. Ensuring a “fair” contact areas among implant crowns is a nightmare. Teeth have mobility…implants not. If you get strong contact areas among implants = you are creating tension that cannot be dissipated (implants cannot move orthodontically). If you get weak contact areas, you have food impaction.
The only reason, in my opinion, for not splinting adjacent implants is aesthetics. I would not splint implants just for aesthetic reasons. Getting a better cosmetic appearance is easier with single crowns and no connectors.
Some can argue that with single implants the patient can use floss. I would argue that 99% of the homo sapiens on this earth do not use floss…and the 1% of homo sapiens who use floss would happily use some super floss or interdental brush for splinted implants.
Last but not least, splinted crowns increase the longevity of the prosthetic work even if some implants, underneath, fail (patient-centered outcomes). Let’s imagine we have 3 adjacent implants: if the patients loose one, the success of the prosthetic work (what patient cares) is yet 100% if the crowns are splinted.