Screw-retained - cement-retained

Aspects of screw-retained and cement-retained restoration designs

Cementation procedures and materials have been reported to cause complications in implant prosthetics, mainly inflammation around the implant due to cement material excess. Cements have been developed for restoration procedures on natural teeth and are based on preparation techniques and designs which are decades old and do not pay attention to designs being considerably different in implant based restoration. Modern implant protocols with reduced diameter implants and at times subcrestal implant placement create horizontal overhangs and leave soft tissue attachments and pockets depths up to 5 and more mm. Studies show that it is not possible to remove cement remnants in this depth, and that cement excess is one of the main risk factors for peri-implant disease complications.To avoid cement related complications, whenever possible, screw-retained systems should be the method of choice.

Expert insights

Cementation procedures and materials have been reported to cause complications in implant prosthetics, mainly inflammation around the implant due to cement material excess. To avoid cement related complications, whenever possible, screw-retained systems should be the method of choice.
Reviews the possible etiology of peri-implant disease, how little knowledge exists in the dental community about cementation techniques and protocols on implants (e.g. how cement flows, the hydraulic forces during cementation). Computational fluid dynamics the attempt to raise awareness: ideal cement application location, adequate amount of cement, speed of crown seating and more.
Starting at 10.28. Detailed explanation of the Angulated Screw-Channel (ASC) System - components and design. Reiterates advantages of screw-retaine design.
Explanation of the Angulated Screw-Channel (ASC) System. Supported by a posterior and anterior restoration example, the lecturer team presents the advantages of this approach and gives handling insights from both clinical and laboratory perspectives.
Starting at 2:20, advantages and limitations of screw- vs cement-retained designs. Cementation procedure aspects at 12:30. Video presents insights in the various aspects which play a role in esthetic restoration design, covering aspects of material selection, framework and emergence profile design, esthetic parameters, cement- and screw retained construction, provisionalization and the advantages of CAD/CAM technology.
Starting at 13.00, aspects of screw- and cement-retained restorations within the treatment planning process and the digital treatment planning protocol.

トリートメントガイドライン

Screw-retained restorations are designed to be screwed either directly onto the implant or onto a screw-retained abutment positioned on the implant (Multi-unit Abutment). Screw-retained restorations represent a secure and easy way to maintain a prosthetic restoration.
A prosthesis directly supported by implants is indicated when inter-arch distance is limited. A prosthesis supported by abutments is indicated when implant angulation needs to be corrected, especially for screw-retained prosthesis designs. Abutments designed for cement-retained restorations are preferred in situations where an access screw hole is not desired.

Digital Textbooks

Single Implants and their Restoration
Single implants and their restoration
"When any restoration, provisional or definitive, is cemented over an abutment, the force of the expressed cement can displace the peri-implant mucosa and cement can be forced apical to the crown margin."