The choice of whether to screw or cement retain an implant restoration remains one considerable debate amongst dental professionals. The traditional rationale for screw retained implant crowns is the retrievability of the restoration.
As a result any complication with the restoration can be addressed. The screw retained restoration can be easily removed which allows for repair or examination of soft tissue and direct visualization of the implant. This also negates the need to remake the restoration if an abutment screw or prosthetic screw loosens.
A more recent argument in favor of screw retention is to eliminate the potential complications associated with excess residual cement – often difficult to completely remove with a cement retained crown. One perceived disadvantage to the screw retained option has been the concern over the visibility of the screw access channel. However, with recently improved esthetic materials, the ability to cover the access hole has become a non-issue.
On the other hand, choosing cement retained as an restorative option provides the assurance of maximum esthetics. The concern with cement retention is two fold. The first being the restoration is cemented to an abutment that is screw retained. If the abutment screw becomes loose then the final restoration cannot be removed without destroying the crown. This results in a remake and increased restorative costs. The second concern with cement retained is that the cementable juntion between the crown and abutment potentially acts as a medium for colonization of bacteria. This is due to the excess cement that may not be fully removed and it can jeopardize the Osseo integration of the implant. This will ultimately result in implant failure.
When deciding between screw retained and cement retained implants, there are benefits and different techniques to using each method, often related to location and position of the implant. The choice of method is usually based on the clinician’s preference and the position of the implant.