Recently I received a call from my laboratory questioning a prescription they had received. The patient had two single unit implants on her lower left replacing the first and second molars. ” The prescription says screw retained and we wanted to call and make sure you really wanted screw retained restorations?” I answered that I did indeed want two screw retained restorations and then was curious about why they questioned this prescription so quizzically. The response I received was that they just don’t get asked to do that very much anymore. I’m not sure what the percentage of cement retained to screw retained crowns are placed these days on implants. In the early days of single tooth implants screw retained was the solution, over time we moved to cement retained. I believe there are still clinical situations where one is preferable over the other as they have unique risks and benefits.
Screw Retained Implant Crowns
- Ability to be used with limited inter-occlusal distance
- Absence of cement under the gingival tissues as a potential irritant
- Predictable retention
- Screw access compromise of occlusal function
Cement Retained Implant Crowns
- Passive Fit of the Implant Crown
- Ideal occlusal form
- Flexibility of fixture placement
- Subgingival Cement Line
- Cleaning of Excess Cement
- Crown Retention
Choosing between the two options requires a knowledge of the clinical situation and both the patient’s and practitioner’s preference.