The rehabilitation of fully edentulous patients represents one of the most challenging and multifaceted tasks in contemporary implant dentistry. The simultaneous restoration of both dental arches requires not only a thorough understanding of surgical and prosthetic principles, but also a careful integration of biomechanical, aesthetic, and functional considerations that must be addressed in a coordinated and sequential manner.
Historically, bimaxillary full-arch rehabilitation has been associated with prolonged treatment timelines, high technical complexity, and a significant risk of complications arising from the lack of standardized protocols.
The traditional analog workflow — based on conventional impressions, plaster models, and manual prosthetic fabrication — has long been recognized as a source of cumulative errors that may compromise the accuracy of the final restorations and, ultimately, the long-term success of the treatment.
Over the past two decades, the advent of digital technologies has profoundly transformed the landscape of implant-supported full-arch rehabilitation. Cone beam computed tomography (CBCT) has enabled three dimensional visualization of the available bone volume and anatomical structures, allowing for a more precise and predictable surgical planning. Computer-aided design and computer-aided manufacturing (CAD/CAM) systems have introduced a new standard of prosthetic accuracy, reducing the human error inherent in analog fabrication techniques. Static and dynamic computer-guided surgery has further enhanced the precision of implant placement, ensuring the correct three-dimensional positioning required for optimal prosthetic outcomes. The integration of intraoral scanning has progressively replaced conventional impressions, offering superior patient comfort and improved digital data quality.
The aim of this article is to present a detailed, step-by-step clinical protocol for the digital-guided rehabilitation of fully edentulous patients with implant-supported fixed prostheses in both arches. Through the description of a representative clinical case, the authors outline a structured workflow that integrates CBCT based planning, computer-guided implant surgery, intraoral digital scanning, and CAD/CAM prosthetic fabrication, with the goal of providing clinicians with a reproducible and evidence-based reference for the management of this complex category of patients.
Fig.1
The patient presented to our attention with an almost complete edentulism, referring that he was impossibilitate to wear his complete prostheses, because he didn’t tollerate them.
He was asking for a complete rehabilitation with two fixed prostheses if it would be possible.
Fig.2
The study of the case started designing two new complete removable dentures able to satisfy both masticatory function and aesthetic appearance.
Fig.3
Once reached a pleasant results it is possible to confirm the project to the technician, and proceed with the manufacturing of two definitive dentures and their replicas with radiopaque landmarks in the vestibular portion to allow to use them in a CBCT examination.
Fig.4
Smile close-up with the desired teeth setup.
Fig.5
Try in of the two replicas with radiopaque landmarks in the vestibular portion. The replicas must be stable and have a correct occlusion contacts as the definitive dentures to allow to do a perfect Cone Beam examination that will be able to give all the info about the available bone in comparison with the teeth position. In order to positioning the implants in a prosthetic driven way.
The landmarks are essential to merge the replicas stl file with the Dicom file in a digital surgical guide software.
Fig.6
In this way it is possible to have in the same examination the available bone volume with the visibility of the landmarks.
Fig.7
It is therefore possible to pair the STL files relating to the two replica prostheses so as to have in a single image the position of the teeth and the bone volumes on which to plan the insertion of the implants with the correct direction. So that, the access screw hole doesn’t lay too palatally or too vestibularly.
Fig.8
It is so possible to move from a view with the replica prostheses to a view without them, in order to control as best as it is possible the implant position in all its details.
Fig.9
It was decided to begin with the lower arch, and the first thing to do is to control the perfect surgical guide seating and its correct occlusion relationship with the opposing arch to confirm its correct execution.
Fig.10
After having fixed the surgical guide with dedicated anchor pins, the gum was incised circularly with a guided mucotome.
Fig.11
Then after having removed the surgical guide is possible to complete the incision and to remove the gum to access the bone.
Fig.12
After having refixed the guide with the anchor pins, it is possible to procede with the guided implants insertion following Dental Tech protocol.
Fig.13
The first two Dental Tech implants just inserted provide a further stability to the surgical guide improving its precision.
Fig.14
At the end of the surgery some scan abutment were screwed to register an optical impression together with the guide by the use of a intraoral digital scanner with the purpose to improve the impression accuracy and precision, and to have the possibility to register the programmed vertical dimension, too.
Fig.15
A second digital impression was then made with the scan abutment alone always screwed on MUA abutments.
Today the horizontal scan abutments are preferred, because they give the possibility to record a more precise and accurate impression.
Fig.16
One day and half from the surgery the soft tissues around the MUA abutment are almost completely healed and ready to receive the prostheses.
Fig.17
The provisional Toronto bridge just screwed at 1,5 days from the surgery.
Fig.18
Opt X-ray to confirm the correct prostheses sitting on the MUA abutment, and the correct Dental Tech implants position as programmed with the surgical software.
It is worth highlighting the reduced diameter of the MUAs, which is capable of optimising their relationship with the soft tissues, without compressing them and above all leaving them the space necessary for their best trophism.
Fig.19
15 days after it is time to procede with the upper jaw surgery.
Fig.20
At the end of the surgery, the impression was taken using the same method used for the lower arch.
Fig.21
The FP1 provisional prostheses just screwed at 1,5 days from the surgery confirming the precision of the Dental Tech protocol and the perfect relation with the opposite prostheses.
Fig.22
Patient’s smile at the same day. Finally he could be happy with his new two fixed prostheses!
Fig.23
Final OPT X-ray confirming the correct execution of the work.
Fig.24
At one year from the surgery the tissue are in good condition, the patient is very capable in maintain a correct hygiene, and everything seems to be correct.
Conclusions
The digital-guided protocol presented in this article represents a comprehensive and reproducible framework for the management of fully edentulous patients requiring bimaxillary implant-supported rehabilitation. By integrating CBCT-based planning, computer-guided surgery, intraoral scanning, and CAD/CAM prosthetic fabrication into a structured, sequential workflow, it is possible to significantly reduce treatment variability, minimize the risk of technical complications, and achieve predictable functional and aesthetic outcomes across a wide range of clinical scenarios.
Bibliography
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