Screw- Versus Cement-Retained Implant Restorations: Current Concepts

[drsushant]

It is more challenging to place a screw-retained restoration in the posterior area when compared with the cement-retained restoration because of the handling of screws and screwdrivers. This problem may be readily observed in cases where the mouth opening is restricted may mimic more treatments of natural teeth and therefore may be preferred by many dentists.

COST

The laboratory cost to fabricate a screw-retained restoration is usually 1.5 to 2 times higher because of the extre time and materials needed (impression transfers, analogs, and screws). There is usually no extra cost to the cement-retianed restoration because no additional training is required to the laboratory technicaian.

PROVISIONAL

Procisional restorations are important in the esthetic area to replace the missing tooth and to shape the soft tissue for a better crown profile.In the posterior area, benefits from a procisional restoration include not only shaping of the soft tissue but also a better assessment of the outcome and anticipation of possible problems with the final crown. For instance, if an adequate thickness of material cannot be optained with the provisional, reshaping the opposing tooth may be necessary before the impression to gain additional interocclucal space.

Cement-retained provisionals are relatively easy to fabricate compared with screw-retained provisionals, because they simulate techniques with natural teeth, which can futher motivate clinicians to make the temporary. Nontheless, the major disadvantage includes the possibility of access cement that can cause tissue inflammation. This is a major problem particularly in cases of immediate loading, where excess cement in the surgical site may compromise healing and implant osseointegration..

Screw-retained procisionals offer the advantage over cement-retained provisionals in the they can be screwed into the master impression to translate additional information to the technician regarding the contour. As the machined surface of screw-rtained restoration are better than cement margins, the selection in cases of immediate loading may favor screw-retained provisionals.

CONCLUSION

Different philosophies exist regarding the ideal type of restoration. The truth is that most of the decisions are based on the clincian’s personal preference and the actual clinical situation. The literature shows advantage and disadvantages for both screw- and cement-retained implant-supported prostheses(Tables 2 and3). An understanding of how each type of prosthesis influences the esthetics, occlusion, and longevity of the restoration is important in selecting the best case for either a screw- or a cement-retained implant-supported prosthesis. It is generally agreed that the currenttrend tends to favor cement-retained implant restorations for ther superior esthetics, occlusion, ease of fabrication, and reduced chairside time