## 3 Discussion  
The current clinical report describes a digital workflow in which the preoperative and postoperative scans were superimposed to transfer the occlusal relationship, aesthetics qualities and gingival tissue to build an immediate interim fixed full-arch prosthesis. They were digitally transferred from the original dentition to the virtual arches. The palatal rugae in the upper jaw and geometrical references on the lower digital index stabilized with an anchor pin anteriorly and with occlusal coverage of the second molar posteriorly provided us a stable point of reference to facilitate a high-quality, interim, fixed, full-arch prosthesis. [PERSON] et al. [11] proposed an alternative method but their approach is not appropriate for patients with a loss of OVD, inadequate occlusal scheme or abnormal occlusal or incisal planes. The presented technique in the presence of one of the previous conditions allows  
Figure 11: Immediate loading of interim fixed prosthesis. (**A**) Interim immediate restoration. (**B**) Extraoral view. Figure 10: Interim restorations exported for computer aided machining (CAM) on hyperDENT\({}^{\text{\text{\textregistered}}}\) software. one to modify the patient's occlusion and maxilla-mandibular relation, while performing at the same time any desired changes before the preoperative scans. However, after the extraction of the teeth, finding markers to fuse digital scans can be difficult, because of the mobility and swelling of the soft tissue after surgery and local anesthesia. The superimposition of the palatal rugae in the maxilla makes it possible to achieve good-fit matching between scans obtaining reliable and stable landmarks in dedentulous patients. In the lower jaw, the use of an acrylic resin digital index anchored to the mandible with occlusal rests over the second lower molar and anterior anchor pin permitted us to avoid the use of multiple miniscerews obtaining a less invasive and more economic procedure. Furthermore, the method proposed by [PERSON] et al. [11] involved the use of CBCT scans to develop a surgical template for prosthetically-guided implant placement, however this template could not be used in the inferior arch due to interference with the resin markers placed on mandibular mini screws that left no space for seating an implant template and forced them to insert them free-hand. In recent years, the implant insertion with CAD/CAM surgical guides has become increasingly widespread. Although there have been high hopes regarding computer guided implant placement, only a few reports discovered the risk of errors and complications that dentists may face between the digital planning stage to implant surgery [14]. Guided surgery is a cutting-edge technique that takes the 3-dimensional (3D) data collected from cone-beam computed tomography (CBCT), optical surface scanning and computer-aided design/computer-aided manufacturing tomography (CAD/CAM) technology for virtual implant planning and fabrication of surgical guides. The various types of surgical guides can be supported by teeth, mucosa or bone and additional support can be achieved using mini-implants, screws or pins [15]. After the guide is fully seated, the planed drilling protocol can begin. The drilling protocol includes using the guide for a pilot drill nobly, a partially, or even a fully guided drilling protocol. The implant insertion can be performed either without the surgical guide or alternatively with the surgical guide for a fully guided approach. The proper case selection and accurate digital implant planning process throughout the digital workflow allow for accurate placement and execution. Guided implant surgery includes multiple additional steps after the initial prosthetic diagnosis, treatment planning and fabrication of surgical guide phases. Significant errors may occur at each of these various phases of care and can ultimately affect the final accuracy of the process with deviations from proper implant placement [16].