Innovative Digital Workflow Using Full-Arch Digital Implant Impression With Horizontal Scanbody: A Case Report

The expansion of these protocols to full-arch implant-supported rehabilitations represents a major advance in digital dentistry. However, the digital transfer of implant positions in extensive cases remains a clinical challenge, as the presence of large edentulous areas and resilient mucosa reduces the availability of anatomical landmarks for intraoral scanning, thus increasing susceptibility to cumulative errors resulting from image stitching and potentially compromising the passive fit of the prosthesis.^7,8

To improve the accuracy of digital acquisition, several strategies have been proposed, including auxiliary reference devices, photogrammetry, and scanbody systems interconnected by rigid bars. Among these approaches, horizontally designed scanbodies represent a promising alternative, as they aim to enhance stability during scanning and facilitate the continuous capture of implant positions in full-arc h rehabilitations. When combined with prosthetically driven implant planning and the integration of CBCT and intraoral scan data, these devices contribute to a more predictable and efficient digital workflow.^9-11

In this context, the present case report describes a bimaxillary implant-supported rehabilitation performed using a fully digital workflow. The case demonstrates prosthetically driven implant planning based on the double-scan computed tomography technique and full-arch digital implant position transfer using horizontally designed scanbodies for the fabrication of implant-supported provisional polymethyl methacrylate (PMMA) prostheses.

Clinical Report

Case Presentation and Virtual Planning

A 54-year-old systemically healthy male patient sought treatment with a chief complaint of esthetic and functional impairment resulting from partial edentulism in both arches. Clinical examination revealed the presence of only the maxillary canines and a few remaining teeth in the mandible. The maxillary canines (teeth Nos. 6 and 11) exhibited advanced bone loss, grade III mobility, and extensive coronal destruction of tooth No. 6. The remaining mandibular teeth (Nos. 21 and 26 through 29) presented with bone loss, mobility, extensive gingival recession, and supra- and subgingival calculus accumulation, rendering their preservation contraindicated.

The patient reported long-standing tooth loss and expressed the desire for a fixed oral rehabilitation. After a discussion of the available treatment options, including conventional complete removable dentures, the patient accepted the proposed treatment of implant-supported complete-arch prostheses in both arches using a fully digital workflow associated with immediate loading.

Informed consent was obtained, and the initial clinical documentation was performed, which along with photographs (Figure 1 and Figure 2) included intraoral scanning of the arches and occlusal registration (Medit i700®, Medit, medit.com), complemented by facial scanning (Miraco Plus 3D Scanner, Revopoint, revopoint3d.com). The digital files were integrated into CAD software (exocad®, exocad GmbH, exocad.com) for prosthetically driven implant planning of the rehabilitation. Based on this planning, mockups were fabricated from Prizma 3D BioProv resin (Makertech Labs, makertechlabs.com) via 3D printing (Mars 5 Ultra, Elegoo, us.elegoo.com) and used for clinical validation of the occlusal plane, vertical dimension, and anterior teeth display. These mockups were subsequently utilized as radiographic guides (Figure 3 and Figure 4).

Surgical and Prosthetic Approach for Mandibular and Maxillary Arches

Following the clinical validation of the prosthetically driven implant planning, CBCT was performed to assess the available bone volume and conduct 3-dimensional planning for implant placement. Tomographic analysis revealed insufficient bone volume in the maxilla for immediate implant placement, determining that the rehabilitation would begin with the mandibular arch (Figure 5).

Intraoral and extraoral antisepsis and local anesthesia with 4% articaine associated with 1:100,000 epinephrine was performed, and the remaining mandibular teeth were removed using a minimally invasive technique. Subsequently, the mandibular implants were placed using a fully guided surgical template obtained from the virtual planning (DTX Studio™ Implant, Nobel Biocare, nobelbiocare.com) (Figure 6). After implant placement, scanbodies were positioned for intraoral scanning and acquisition of digital files intended for the fabrication of the immediate-load implant-supported provisional prosthesis.

During the same surgical session, bilateral maxillary sinus floor elevation was performed using a particulate freeze-dried human bone graft (Unioss, unioss.com.br), associated with the application of leukocyte platelet-rich fibrin (L-PRF) membranes (Figure 7). For a provisional maxillary rehabilitation, a complete denture printed in biocompatible resin (A2) was installed, designed without a buccal flange to avoid excessive lip support and preserve a more natural facial profile during the healing period. An implant-supported provisional mandibular rehabilitation was also installed with immediate loading (Figure 8 and Figure 9).

Second Surgical Phase and Tomographic Alignment Protocol

After the osseointegration period for the maxillary graft, the second surgical phase was initiated. The provisional maxillary complete denture was duplicated via 3D printing and modified with the insertion of six gutta-percha tomographic markers (1.5 mm in diameter), bilaterally distributed to enable the alignment of the imaging examinations.

Virtual planning was performed using the double-scan technique. CBCT acquisition was initially performed with the prosthesis in the intraoral position, followed by a second low-dose radiation scan of the prosthesis alone. The DICOM files were imported into the planning software (DTX Studio Implant), where the bone reconstruction was superimposed onto the prosthetic anatomy through the alignment of radiopaque markers, allowing refinement of the 3-dimensional implant positioning according to the prosthetic planning for surgical guide fabrication (Figure 10).

Based on this planning, a surgical guide was fabricated in occlusal splint resin (PriZma 3D Bio Splint, Makertech Labs) containing metallic sleeves (Nobel Regular, Nobel Biocare) (Figure 11). After local anesthesia, the residual roots of teeth Nos. 6 and 11 were removed using a conservative technique, and the guide was stabilized with bone anchorage pins for guided surgery.

The implants were placed according to the virtual planning in the regions of teeth Nos. 3 (4.3 mm x 11.5 mm with a 3.5-mm abutment collar height [H]), 4 (4.3 mm x 13 mm with a 2.5-mm H), 5 (4.3 mm x 16 mm with a 2.5-mm H), 14 (4.3 mm x 13 mm with a 3.5-mm H), and 13 and 12 (4.3 mm x 11 mm with a 2.5-mm H). NobelActive® implants (Nobel Biocare) were used, except in the region of tooth No. 3, where a NobelReplace® Conical Connection implant was placed. All implants achieved an insertion torque of 35 Ncm, allowing the immediate placement of conical mini abutments (EFF Dental, effdental.com.br) (Figure 12 and Figure 13).

Digital Transfer and Prosthetic Rehabilitation

The digital transfer of implant positions was performed using Scan Intraoral Ti Full Arch devices (EFF Dental), developed for digital acquisition in full-arch rehabilitations. These devices have a horizontal design and metallic structure to provide good continuity during intraoral scanning (Medit i700), minimizing interruptions in optical acquisition across extensive edentulous areas and facilitating the capture of the 3-dimensional implant positions (Figure 14 and Figure 15).

After two days, the accuracy of the digital transfer was clinically verified through the passive fit of a milled verification metal framework (INDEX, ERO Prótese, eroprotese.com.br), which was subsequently confirmed by radiographic evaluation (Figure 16 through Figure 18).

Subsequently, the prosthetic rehabilitation was performed. For this purpose, based on the intraoral scans, the extraoral scan of the provisional complete denture, and the subsequent facial scan with the prosthesis in position, CAD software was used to align the files. Dental anatomical regions (incisal edge of teeth Nos. 8 and 9) and palatal rugae were used as references to achieve alignment among the scans. The digital files were imported into CAD software (exocad), where the virtual design of the prosthesis was performed using a virtual articulator (Figure 19).¹² The definitive transitional prosthesis was fabricated (ERO Prótese) in glass-filled PMMA (PMMA Hybrid Blue Dent, Blue Dent, bluedent.com.br) (Figure 20 and Figure 21) and cemented onto metal links (EFF Dental) compatible with the installed implants. The prosthesis was installed over the mini abutments according to the torque recommended by the manufacturer, establishing a long-term immediate loading protocol (Figure 22 through Figure 24). The installation was performed 4 days after surgery.

After 12 months of follow-up, stability of the peri-implant tissues and favorable clinical conditions were observed (Figure 25).

Discussion

Implant-supported rehabilitations have demonstrated high clinical predictability and success rates, representing an established approach for the treatment of partially or completely edentulous patients.^1-4 In the present case report, these benefits were enhanced by the use of a fully digital workflow, in which diagnosis, prosthetically driven implant planning, guided surgery, and prosthetic rehabilitation were integrated into a continuous clinical sequence.

Obtaining an accurate transfer of the 3-dimensional implant position remains a key determining factor for the passive fit of implant-supported prostheses. Among conventional techniques, open-tray impression procedures using splinted impression copings and addition silicone impression material are still considered the reference approach for multiple and full-arch rehabilitations due to their high clinical predictability.^5-7 However, digital workflows have demonstrated the potential to simplify clinical and laboratory procedures by reducing the number of operative steps, chairside time, and the need for manipulation of impression materials, while also improving communication between the clinician and the dental laboratory.^8-13

In the present case, the digital workflow enabled the integration of all treatment stages, from prosthetically driven implant planning to the fabrication of implant-supported provisional prostheses, maintaining consistency between virtual planning and clinical execution. Another relevant aspect was the use of the double-scan computed tomography technique associated with guided surgery, which enabled the alignment between anatomical structures and the previously established prosthetic anatomy. This integration facilitated 3-dimensional planning consistent with the restorative proposal and contributed to the predictability of immediate implant placement and immediate loading.^14-17

The digital transfer strategy used in this case employed horizontal scanbodies developed for digital acquisition in full-arch rehabilitations. Unlike conventional scanbodies, this design aims to provide greater continuity during intraoral scanning, particularly in extensive areas with limited anatomical references. Although clinical evidence is still limited, the passive fit of the verification metal framework at the first clinical try-in, subsequently confirmed radiographically, demonstrated compatibility between the virtual planning and the digital transfer of implant positions, suggesting that this approach may represent a promising alternative for optimizing the digital workflow in full-arch implant-supported rehabilitations.

This potential is supported by recent studies demonstrating that horizontal scanbodies provide greater geometric stability during intraoral scanning, reducing the accumulation of errors along extensive arches and increasing the accuracy of implant position transfer. These characteristics make their application particularly relevant in immediate loading protocols, in which the accuracy of digital impressions is essential for adequate prosthesis seating. Although scanning performed immediately after implant placement remains a clinical challenge due to the presence of blood, saliva, and soft tissues, clinical evidence indicates that the use of oriented horizontal scanbodies enables the acquisition of digital scans with deviations within clinically acceptable limits.^18,19 The findings of the present case are consistent with these observations, although the outcome obtained should not be attributed exclusively to the use of these devices, since clinical predictability also depends on the integration among virtual planning, guided surgery, the intraoral scanning technique, and subsequent laboratory procedures.

Although the present case report demonstrates the feasibility of a fully digital workflow associated with the use of horizontal scanbodies in full-arch implant-supported rehabilitations, the available evidence remains limited. Therefore, prospective clinical studies with larger samples and longitudinal follow-up are necessary to confirm the accuracy, predictability, and applicability of this strategy in different clinical scenarios.

Conclusion

This case report demonstrates that a fully digital workflow may represent a viable alternative for full-arch implant-supported rehabilitations, allowing the integration of virtual planning and clinical execution in a predictable manner. The use of horizontal scanbodies associated with prosthetically driven implant planning, the double-scan computed tomography technique, and guided surgery proved to be clinically applicable in this case. Prospective clinical studies, however, are needed to confirm the accuracy and predictability of this approach in full-arch rehabilitations.

ABOUT THE AUTHORS

André Luis Soratto, DDS, MS

Professor, Department of Implantology, University of Marília, Marília, São Paulo, Brazil

Jean Albuquerque Barros, DT

Dental Technician, São Paulo, Brazil

Renato Sartori Lardin Sanchez, DDS, MS

Clinical Practice, São Paulo, Brazil

Gabriela Aparecida dos Santos, DDS

Master’s Degree Student, Department of Prosthodontics, Faculty of Dentistry, University of São Paulo, São Paulo, Brazil

Newton Sesma, DDS, MSc, PhD

Professor, Department of Prosthodontics, School of Dentistry, University of São Paulo, São Paulo, Brazil

Emily Vivianne Freitas da Silva, PhD

Professor, Department of Prosthodontics, School of Dentistry, University of São Paulo, São Paulo, Brazil