As implant dentistry becomes an ever-larger part of general practices, choosing between a cementable or screw-retained implant crown is now a frequent decision that clinicians have to make. Patients invest considerable time and money to receive implant treatment, and the final result can determine how happy they are with their overall experience and whether they’ll recommend your practice to friends and family. Further, chair time is a more valuable commodity than ever, and selecting a restoration that can be delivered as efficiently as possible while minimizing the need for adjustments is of paramount importance. With this in mind, here are the eight most important factors to consider when deciding between a screw-retained restoration or a cement-retained restoration.

1. The Angulation of the Implant
2. Restorative Space
3. Path of Draw
4. Ease of Delivery
5. Retrievability
6. Margin Placement
7. Peri-Implant Health
8. Esthetics

Implant angulation is a key deciding factor when determining which type of restoration to deliver. When the position of the implant allows for a screw access channel that exits through the cingulum of an anterior implant restoration or the central fossa of a posterior implant restoration, selecting a screw-retained prosthesis is advantageous due to ease of delivery and the elimination of any concerns related to residual cement at the implant site.

For this reason, the facial-lingual bone volume and contours of the implant site should be evaluated during treatment planning to determine if the implant can be positioned to support a screw-retained restoration. If the implant must be positioned at an angle that results in the access hole of a screw-retained restoration exiting through the facial aspect of the prosthesis, correcting the angulation of the implant with a custom abutment and cement-retained crown is a great alternative, esthetic solution.

In keeping with a prosthetically driven approach to implant dentistry, clinicians should evaluate the available restorative space as the treatment plan is developed. If there is limited space between the implant site and the opposing dentition, a screw-retained restoration is recommended because less restorative height is required. This is because the height of a custom abutment must be sufficient to predictably retain the cementable crown. For this reason, as well as the simplified, cement-free method of delivery, positioning the implant to support a screw-retained restoration when space is limited is an important factor for long-term success.

When delivering an implant restoration, the internal connection of the implant should achieve a path of draw that aligns with the adjacent teeth. Custom abutments are advantageous in cases where achieving the appropriate path of draw is challenging. They are customized to create a path of draw between the adjacent teeth. In addition, they are designed to achieve the optimal retention and resistance form, ideal margin placement for easier cement removal, and a customized emergence profile for soft-tissue and restorative material support.

Screw-retained crowns have surged in popularity due to the simple, cement-free procedure involved in delivering the restoration. After seating the crown and torquing the prosthetic screw, the access hole is filled, bonding agent is placed, and composite is used to seal the opening. With custom abutments, similar steps are required but with the addition of the cementation step, which requires additional time and great care in ensuring that any excess cement is completely removed from the site. Considering the importance of chair time in the modern dental practice, it’s not hard to see why screw-retained crowns have become the preferred option for many dentists. That being said, cementable restorations remain a common choice among clinicians, as there will always be cases where implants are placed at an angle that requires correction with a custom abutment. Also, some dentists are more comfortable delivering a cementable restoration due to the procedure’s similarity to that used in traditional crown & bridge.

The ease of restoration retrieval is another consideration clinicians should keep in mind when selecting an implant prosthesis. Screw-retained crowns have access channels that can be easily located, simplifying removal should restoration chipping, gingival irritation, screw-loosening or esthetic changes occur over time. Conversely, cementable implant restorations can be difficult to retrieve as the crown needs to be cut away to locate the abutment access channel.

As an alternative, a custom abutment and cementable crown can be converted into a “screwmentable” restoration, which avoids concealing the access channel, creates a more favorable emergence profile for angled implants, and provides ample support for the restorative material of the crown. For information on how to prescribe this solution and complete fabrication of the restoration in your office, see my Chairside^® magazine article on the topic here.

When restoring an implant case, it’s important to note how your selection of restoration type affects the margin placement of the crown. For a screw-retained restoration, the margin, or connection, between the implant and crown is situated approximately 0.5–1.0 mm above the implant platform. This is beneficial for patients with a thin gingival biotype, as it minimizes the appearance of metal showing through the soft tissue.

For cementable restorations, ideal margin placement is equigingival or up to 0.5 mm below the gingival surface to ease the cleanup of residual cement during crown delivery and maximize esthetics for this restorative option. If a cement-retained restoration is desired and the patient has a thin biotype, contact your laboratory to learn more about anodizing the custom abutment for a more esthetic outcome.

The method of crown delivery has a considerable impact on the health of the peri-implant bone and soft tissue, but either method of retention can support a predictable long-term outcome if the proper techniques are utilized. As previously mentioned, screw-retained crowns eliminate concerns with residual cement because the abutment and crown are cemented together in the lab, eliminating the risk of leaving behind cement during intraoral cementation. However, when a cementable restoration is chosen, the use of a custom abutment instead of a stock abutment makes the removal of excess cement more predictable because it allows for ideal margin placement. In either case, great care should be taken in removing all excess cement from the site during the final delivery procedure.

As mentioned above, the margin, or connection point, of the screw-retained abutment and crown can offer esthetic advantages when there are concerns of metal show-through with a thin gingival biotype. However, the access channel of the restoration can remain visible, which some esthetically minded patients may not like, especially in the posterior mandible. If screw-retention is the method of choice in such cases, material selection is important so that the access hole is sealed in a manner that blends well with the occlusal table of the tooth.

Also note that for cementable restorations in the anterior, selecting a zirconia abutment with a titanium base or a gold-tone custom abutment can result in superior, lifelike esthetics.

When choosing between a screw-retained and cementable implant solution, the decision largely depends upon the unique clinical circumstances of the case at hand and the preferences of the dentist. With the precision of modern CAD/CAM technology, the patient-specific contours of both custom abutments and screw-retained crowns align precisely with the patient’s soft tissue anatomy and enable predictable seating of the restoration. By following the guidelines above, you can provide an excellent long-term outcome while meeting or exceeding the expectations of the patient.