IADR Abstract Archives
Hybrid Screwmentable Implant-Supported Restorations: a Systematic Review and Case Series
Objectives: Traditionally, implant-supported restorations are either cement- or screw-retained. Lately, a hybrid design that combines advantages of both previous categories has been adopted by clinicians. Such prostheses consist of a suprastructure with a screw access channel, which is permanently cemented on a customized abutment or a prefabricated base; thus, the restoration is being screwed as one-piece into the implant body. Aim of the present systematic review was to identify data on hybrid screwmentable prostheses and evaluate their long-term performance. A series of clinical cases is also presented.
Methods: The search strategy followed the guidelines of the preferred reporting items for systematic reviews and meta-analyses (PRISMA). The electronic search was conducted by using the PUBMED, Cochrane and Google Scholar databases and was supplemented by a hand search by two independent reviewers. Inclusion criteria were studies on the hybrid type of prosthesis with publication dates from 2004 to April 2020.
Results: The search concluded in 494 records. After screening 24 were finally included in the review. These presented significant heterogeneity concerning the manufacturing process and the materials used. Some authors opted to cement the supraconstruction directly onto the abutment (two-piece restoration), while others machined a mesostructure (abutment), which was bonded onto a titanium-insert (three-piece). Zirconia, lithium disilicate and titanium alloy constitute the materials of choice for the fabrication of such prostheses. The aesthetics, mechanical and biological properties of screwmentable restorations appeared satisfying. Data on the survival and success rates are limited. Debonding and restrictions connected with the screw access channel were reported as disadvantages. These can be avoided by technique optimization, as described in the case series.
Conclusions: The hybrid screwmentable design is a promising alternative for implant-supported restorations by providing passive fit, retrievability, and excess cement control. Further studies are required to evaluate long-term clinical behavior.
Methods: The search strategy followed the guidelines of the preferred reporting items for systematic reviews and meta-analyses (PRISMA). The electronic search was conducted by using the PUBMED, Cochrane and Google Scholar databases and was supplemented by a hand search by two independent reviewers. Inclusion criteria were studies on the hybrid type of prosthesis with publication dates from 2004 to April 2020.
Results: The search concluded in 494 records. After screening 24 were finally included in the review. These presented significant heterogeneity concerning the manufacturing process and the materials used. Some authors opted to cement the supraconstruction directly onto the abutment (two-piece restoration), while others machined a mesostructure (abutment), which was bonded onto a titanium-insert (three-piece). Zirconia, lithium disilicate and titanium alloy constitute the materials of choice for the fabrication of such prostheses. The aesthetics, mechanical and biological properties of screwmentable restorations appeared satisfying. Data on the survival and success rates are limited. Debonding and restrictions connected with the screw access channel were reported as disadvantages. These can be avoided by technique optimization, as described in the case series.
Conclusions: The hybrid screwmentable design is a promising alternative for implant-supported restorations by providing passive fit, retrievability, and excess cement control. Further studies are required to evaluate long-term clinical behavior.