CAD/CAM abutments allow individualization of abutment parameters with respect to soft tissue, allow increased fracture toughness, predict the failure mode, show no change in the fracture toughness over time, reduce the prosthetic steps, and reduce the functional implant prosthesis score and pain perceived by patients in the early stages. The advantages associated with the use of stock abutments mainly concern the risk of corrosion, time spent, cost, and fit, evaluated in vitro, in the implant–abutment connection. Equal conditions are present regarding the mechanical characteristics during dynamic cycles, screw loss, radiographic fit, and degree of micromotion.
CAD/CAM Abutments Advantages |
References and Study Details |
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CAD/CAM abutments containing titanium inserts had higher fracture resistance than solid zirconia abutment; this conditioned the type of fracture, mainly horizontal, and the location of the fracture, mainly buccal, distant from the implant platform. |
Chang et al. 2022 [39]: in vitro investigation comparing three groups of zirconia abutments (n = 5) consisting of different connection designs or manufacturers (All-Zr, ASC-Zr, and AM-Zr groups) |
All prosthetic parameters are modifiable, including emergence file, thickness, outer contour, position of the finish line in relation to the roots of contiguous tooth elements and the gingival margin, predictable fit, and durability. |
Cantieri Mello et al. 2019 [29]: systematic review and meta-analysis of 11 in vitro studies |
After 1 year of clinical service, no difference in fracture toughness was found for the CAD/CAM zirconia abutments compared with their pristine copies. |
Schepke et al. 2019 [40]: ex vivo study on 23 stock and 23 CAD/CAM customized zirconia implant abutments |
Two-piece CAD/CAM zirconia abutments with an internal–hex connection demonstrated greater fracture resistance than one-piece CAD/CAM zirconia and stock zirconia abutments. |
Gehrke et al. 2015 [41]: in vitro experiments on 21 abutment-crown specimens Mostafavi et al. 2021 [23]: randomized clinical trial with 50 participants |
Excellent finish, compensates poor implant angulation, and supports and interacts with soft tissue. |
Valsan et al. 2021 [21]: clinical report |
CAD/CAM healing abutments require fewer steps for prosthetic finalization than standard healing abutments, allow for a higher functional implant prosthodontics score, and perceived pain is less in the early stages of prosthetic rehabilitation. |
Beretta et al. 2019 [42]: randomized controlled clinical trial with 20 participants |
Screw-retained implant crowns based on CAD/CAM zirconia abutments with conical connection exhibited excellent clinical performance. |
Fonseca et al. 2021 [26]: prospective cohort study, with a 4.5–8.8-year follow-up on 32 patients with 40 implant single crowns |
CAD/CAM abutment-supported restorations in titanium and zirconia have lower mean papillary recession index than stock abutments, improving papilla support and avoid excessive papilla compression. |
Lops et al. 2017 [28] and Lops et al., 2015 [30]: 2-year prospective multicenter cohort studies |
Reduction of the risk of cement remaining deep in the peri-implant sulcus in the cemented prosthesis. |
Edelhoff et al. 2019 [19]: review |
Abutment material does not determine any significant difference in the degree of papillary recession for either stock abutments or CAD/CAM abutments made of titanium and zirconia, given the biocompatibility of these materials. |
Haugen et al. 2022 [31]: review and meta-analysis respectively including 100 and 30 studies |
Stock abutments advantages |
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One-piece CAD/CAM zirconia abutments have lower static fracture loads than their stock counterparts. |
Alsahhaf et al. 2017 [25]: in vitro study on 80 abutments Jarman et al. 2017 [43]: in vitro study on zirconia abutments Yilmaz et al. 2015 [44]: in vitro study comparing load to failure for 5 zirconia abutments for an internally hexagon implant |
The volume of material involved in the implant-abutment connection is higher than CAD/CAM titanium abutments and the frictional fit achieved with the stock abutment is better than the CAD/CAM abutment connected to the same implant system. |
Lops et al. 2018 [36]: in vitro study comparing 10 CAD/CAM titanium abutments with 10 stock titanium abutments Alonso-Pérez et al. 2017 [37]: in vitro study comparing 13 implants connected to original stock abutments and 13 implants connected to nonoriginal laser-sintered abutments |
Better internal fit with respect to CAD/CAM abutments |
Lops et al. 2018 [36]: in vitro study comparing 10 CAD/CAM titanium abutments with 10 stock titanium abutments Apicella et al. 2010 [35]: radiographic and SEM analysis on 12 titanium abutments, 12 stock zirconia abutments, and 12 third party zirconia abutments |
Less risk of corrosion due to the possible use of different alloys in the milled parts; less time-consuming and expensive. |
Ragupathi et al. 2020 [45]: in vitro study on 10 titanium abutments and 10 PEEK abutments Souza et al. 2020 [46]: review |
Industrial manufacturing process standardizes the quality of the product and ensuring the use of biocompatible materials in the abutment/soft tissue interface. |
Mostafavi et al. 2021 [22]: literature review |
Common aspects |
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After application of 5000 cycles of cyclic loading, with a force between 10 N and 250 N, there is no significant difference in screw loosening with titanium stock abutment or titanium CAD/CAM abutment, highlighting that the connection of the CAD/CAM abutment to the fixture was as stable as that of the stock abutment. |
Paek et al. 2016 [32]: in vitro study on stock and customized CAD/CAM abutments |
Micromotion at the implant-abutment interface does not present significant differences between zirconia CAD/CAM abutments and titanium stock abutments. |
Karl and Taylor 2014 [38]: in vitro study on CAD/CAM zirconia and CAD/CAM titanium abutments |
Radiographic and scanning electron microscopy (SEM) investigations have shown that the fit achievable with CAD/CAM abutments is comparable to that of stock abutments. |
Apicella et al. 2010 [35]: radiographic and SEM analysis on 12 titanium abutments, 12 stock zirconia abutments, and 12 third party zirconia abutments |
Two-piece CAD/CAM zirconia abutments are an equivalent alternative to titanium abutments in a single-implant restoration in the anterior region. |
Wittneben et al. 2020 [24]: 3-year randomized clinical trial |
After dynamic loading, microgap values at the implant-abutment interface are equivalent, demonstrating that CAD/CAM zirconia abutments can withstand functional forces as well as stock titanium abutments. |
Coray et al. 2016 [27]: systematic review and meta-analysis on 7 studies |
This entry is adapted from the peer-reviewed paper 10.3390/prosthesis4030038