Purpose: The aim of this systematic review was to evaluate the existing scientific evidence on human clinical studies describing the application of computer-aided design/computer-assisted manufacturing (CAD/CAM) technology in restorative implant dentistry.
Materials and methods: Electronic searches for clinical studies from 1966 through May 2008 focusing on long-term follow-up were performed using the PubMed search engine. Concentrating on the restorative aspect of the CAD/CAM technology applicable to implant dentistry, pertinent literature was divided into articles related to implant abutments and implant frameworks.
Results: Of the 885 articles initially reviewed, 5 articles (3 CAD/CAM framework and 2 CAD/CAM abutment) satisfied the search criteria of the literature search performed. Combining the results from the framework clinical trial studies, there were a total of 189 prostheses supported by 888 implants. The follow-up varied between 12 and 60 months. Four implants were lost prior to the insertion of the prosthesis and 46 after the insertion. One prosthesis failure was reported. Similarly, in the 2 abutment clinical trial studies there were a total of 53 ceramic abutments supported by 53 implants. The patients were followed between 12 and 44 months. No significant failures or complications were reported in association with the implants and their restorations.
Conclusions: Based on a systematic review of literature concerning CAD/CAM used for fabrication of frameworks and abutments, preliminary proof of concept was established. Clinical studies on the use of these techniques were too preliminary and underpowered to provide meaningful conclusions regarding the performance of these abutments/frameworks.