Dr. Alessadro Agnini
• Dr. Agnini works in private practice in Modena and Sassuolo, Emilia Romagna, Italy, following his brother, Andrea, specialized in fixed prosthodontics, periodontology, and implantology.
• He attended the NYU College of Dentistry with Dr. Dennis Tarnow, Dr. Christian Stappert, Dr. Stephen Chu, Dr. Michael Bral. He is currently a Clinical Research Fellow of the Ashman Department of Periodontology and Implant Dentistry at NYU, with Dr. Sang Choon Cho.
• He is a co-author of Italian and international scientific publications.
• Since 2007 he has been a Clinical Fellow of an annual course of Fixed Prosthetics, Periodontology and Implantology based at his brother Andrea’s, who is the scientific director.
• Andrea Agnini
• Tommaso Matteucci
• Giulia Benedetti
• Pierfrancesco Golfarelli
Digital dentistry has not only aided dentists in planning and executing procedures but has also brought the patient to the forefront of treatments. In an era of rapid technological advancements, the dental community stands at a transformative moment.
The use of digital tools enables multidisciplinary planning and treatment using patient-specific images to plan the case in 3 dimensions virtually. Everything starts with the intraoral scan.
This article describes a full-arch implant-based rehabilitation and how digital tools, specifically the iTero Lumina™ scanner, helped to streamline the workflow, ensuring predictable and accurate results within a multidisciplinary approach.
introduction
introduction
The loss of natural teeth through decay, periodontal disease, or trauma significantly impacts mental health and well-being and reduces quality of life in general.
Terminal dentition is a clinical situation which refers to when a significant number of teeth are so compromised that either they cannot be restored or patients have inadequate teeth support. Determining the parameters that can lead to the diagnosis of a terminal dentition can be challenging due to the multifactorial nature of compromised dentition. For a successful treatment plan, under- or over-treatment must be avoided.
Various analog and digital protocols have been proposed to treat these cases. While the efficacy of analog protocols has been proven, they are time-consuming and technique-sensitive. On the contrary, digital approaches increase efficiency in treating these cases.
Intraoral scanners are one of the most exciting new areas in dentistry. They simplify clinical procedures for clinicians and allow for more efficient communication with the dental laboratory. The accuracy of the captured data ensures the passive fit of the prosthetic structure, a key element of clinical success, and analyzing the accuracy of the full-arch scan cannot be overlooked.
The intraoral scanner is not the only factor involved in determining the final accuracy of an optical impression: the operator, patient, lighting conditions, and the choice of scan bodies also play key roles. Moreover, the experience of the clinician and the technician are relevant factors as well.
Modern technology is a valuable aid to achieving optimal accuracy in data capture. The iTero Lumina™ scanner is powered by the new, proprietary iTero Multi-Direct Capture™ technology developed to capture more data [1] quickly [2] and accurately [3] while maintaining exceptional scan quality. In a recent study by Baresel et al. [1], it demonstrated superior full-jaw accuracy compared to tested competitors. For full-arch rehabilitations of implants, it achieves an accuracy comparable to photogrammetry [4], which is today considered the gold standard methodology for full-arch digital impressions.
case description
case description
Per the clinic protocol, an intraoral scan was taken during the visit, which helped both in the diagnostic process and in educating the patient about the clinical findings. After a complete examination, we established the diagnosis as terminal dentition in the upper jaw, with medium carious receptivity and generalized stage 4, grade B periodontitis.
The treatment plan included implant-prosthetic rehabilitation of the upper arch, implants in the lower posterior mandible to restore chewing function, and conservative treatment of the incisal ridges of the lower frontal group to improve anterior guidance. The initial step was a smile design to study the case and explain the potential outcome to the patient. This design formed the basis to create an upper reinforced provisional fixed restoration. In this phase, we began the teeth extraction and infection control.
Next was the digital full-arch implant prosthetic workflow divided into 3 stages:
• Virtual planning
• Guided surgery – treatment execution
• Treatment finalization
The intraoral scan provided information on functionality, which is central to temporary restoration and the anatomy of the upper jaw. Photos, videos, and facial scans were also acquired and sent to the dental laboratory. A single 3D smile design was created using Smile Creator software by superimposing the data obtained from the intraoral scanner (iTero Lumina™ scanner) and cone beam computed tomography (CBCT). This approach enabled the design of a metal-free prototype, which was positioned in the mouth during a 3D X-ray examination together with an extraoral reference (Evobite, 3DM). In the laboratory, the digital imaging and communications in medicine (DICOM), CBCT, standard tessellation language (STL), and OGG video (OGV) data were superimposed in the Exocad planning software.
In this case, the digital computer-aided design (CAD) design of the prototype and functional anatomical shapes was completed, considering the teeth still present in the arch, which serve as stabilizers both in the prototype trial and in the future implant guide template. The prototype was 3D-printed in Dreve white resin.
The angulation of the 4 implants was planned to promote engagement in the native maxillary bone, thereby favoring primary stability, allowing for immediate loading, and limiting the need for regeneration techniques.
“The pre-angled multi-unit and provisional titanium abutments were aligned with the working arch.”
After planning the implant position, the parameters of the pre-angled multi-unit and provisional titanium abutments were aligned with the working arch, and the files were transferred to the laboratory for the manufacture of the reinforced provisional restoration.
For this purpose, during the CAD design phase, the reinforcement bar and its superstructure, which will be the esthetic-anatomical part of the provisional restoration, were designed using the double-bar technique. The latter must possess all the functional and esthetic characteristics of the tested prototype and all the structural and emergence profile details established during the virtual design.
In the computer-aided manufacturing phase, it was prototyped with a titanium laser melting technique; the esthetic part is usually produced with dedicated composite resins, which can be printed using a 3D printer (Asiga). The bar and esthetic counterpart are assembled and cemented after chemically and mechanically activating the surfaces with resin cement.
To ensure the execution according to the detailed plan, we used a stackable guide system for the surgery. The multi-unit abutment guide facilitated the correct seating of the abutments, which were tightened to 30 N. The provisional titanium abutments were screwed onto these and glued to the provisional restoration using resin cement. Later, the provisional restoration was unscrewed, finished, and polished in the laboratory.
The last clinical step involved screwing the temporary restoration with a torque of 20 Ncm. An esthetic, functional, and passivation check was performed on the prosthesis and its emergence. As described by Pozzi, a prosthetic biologic space of 2–3 mm is required between the pontic’s base and the bone crest to avoid epithelial thinning and other adverse biological responses. Finally, simple sutures were placed with a 5/0 polytetrafluoroethylene suture.
FIG. 8A-H Steps of the surgical procedure done with a stackable screw retained metal guide and the healing phase at 4 months with the scanbody in position.
The final phase of prosthetic rehabilitation begins after 4 months of implant osseointegration, provided there are no biological or mechanical complications.
The iTero Lumina™ scanner was used to capture the intraoral scan, following a precise scanning protocol:
- Scan of the upper provisional restoration
- Scan of the provisional lower restoration
- Bite scan
- Scan of the upper scan bodies
- Extraoral scan of the upper and lower provisional restorations
Utilizing the Multi-Direct Capture™ technology, which employs direct light technology (unlike all other intraoral scanners available on the market today, which use an indirect light approach), this procedure was simple, efficient, and delivered high-quality STL files. Moreover, it facilitates the scanning of edentulous gaps due to its deep and wide field of capture, enabled by the 6 cameras positioned at the tip of the iTero Lumina™ wand.
“The superstructure consisted of a full monolithic zirconia ensuring good optical properties and optimal strength; it was assembled with the titanium bar.”
The final restoration process begins by combining the intraoral STL files with the extraoral scan into the digital master model. The aluminum bar is used as a jig to check the passive fit both clinically and radiographically.
Next, the technician proceeded with designing the prototype to be tested intraorally, controlling for restoration accuracy, esthetic and occlusal parameters, as well as peri-implant soft tissue adaptation. After the try-in, the prototype was scanned extraorally to transfer modifications made intraorally to the virtual design.
The superstructure consisted of a full monolithic zirconia, ensuring good optical properties and optimal strength. It was assembled with the infrastructure.
FIG. 11A-D Final design of the restoration which follows the prototype test drive appointment.
For the cementation, we used a universal primer to promote a strong adhesive bond between luting composites and all indirect materials. The primer serves as a bonding agent to create a durable chemical bond between the titanium bar and the zirconia supra structure. The titanium bar was sandblasted until an even matte surface was achieved. The zirconia was also sandblasted, per the manufacturer’s guidelines, and rinsed with water spray. A thin primer coat was then applied to the pretreated titanium bar and the zirconia prostheses with a brush. A self-curing dental luting composite was then used to bond the zirconia prosthesis onto the titanium bar. This construction ensures a very stable and biocompatible screw-retained implant restoration. The occlusal surfaces were polished to minimize the wear of the antagonist. The prostheses were decontaminated in an ultrasonic bath with an isopropanol solution and steam cleaned.
After the restoration was placed, the occlusion was verified, and the screw access channels were filled with medical-grade polytetrafluoroethylene tape (SilverPlug).
A Vivera™ retainer was then produced utilizing a digital impression to avoid unexpected changes and nocturnal stresses, which can damage the restoration.
CONCLUSIONS
CONCLUSIONS
Accurate data capture for digital planning is key to minimizing errors along the multiple steps involved in complex cases. The choice of intraoral scanner and scanning strategy help create predictable outcomes. Multi-Direct Capture™ technology is a game changer in ensuring accurate full-arch scans comparable to those of photogrammetry devices [4] without the need for supplementary equipment.
The success of prosthetic rehabilitation is long-term stability. New technologies and materials provide excellent tools to simplify workflows and facilitate effective and efficient restoration, even in complex cases. The combination of digital workflows in all treatment phases, along with the selection of appropriate materials, simplifies treatment execution and helps address esthetic, functional, and biological needs.
SOURCES
(1) Baresel I, Baresel J, Full arch accuracy of intraoral scanners with different acquisition technologies: An in vitro study, Journal of Dentistry,V156,2025
(2) Mitrani R, Papaspyridakos P. Treatment planning algorithm for patient with a terminal dentition. J Prosthet Dent 2024 – May: 04-029
(3) Ntovas P, Grybauskas S, Beiglboeck FM, Kalash Z, Aida S, Att W. What comes first: teeth or face? Recommendations for an interdisciplinary collaboration between facial esthetic surgery and dentistry. J Esthet Restor Dent 2024
(4) Agnini Al, Agnini An, Stappert CF, Pariente L. Romeo D. Clinical investigation on axial versus tilted implants for immediate fixed rehabilitation of edentulous arches: preliminary results of a single cohort study. Clin Implant Dent Relat Res 2014
(5) Blatz M, Coachman C. The complete digital workflow in Implant Dentistry. Compend Continu Education 2023
(6) Agnini Al, Agnini An, Benedetti G. Digital Dental Revolution 2.0. Quintessence Publishing 2023, Milano, Italy
(7) Coachman C, Calamita MA, Sesma N. Dynamic Documentation of the Smile and the 2D/3D Digital Smile Design Process. Int J Periodontics Restorative Dent 2017
(8) Joda T, Balmer M, Jung RE, Ioannidis A. Clinical use of digital applications for diagnostic and treatment planning in prosthodontics: A scoping review. Clin Oral Implants Res 2024
(9) Meda RG, Esquievel J. Treating Terminal Dentition with FP1 Prostheses: a digital perioprosthodontic approach. QDT 2025
(10) Bishara M, Miron RJ. A digital approach to immediate load full arch implant dentistry. A case report. Int J periodontics Restorative Dent 2022
(11) Flügge T, Kramer J, Nelson K, Nahles S, Kernen F. Digital implantology- a review of virtual planning software for guided implant surgery. Part II: Prosthetic set-up and virtual implant planning. BMC Oral Health 2022
(12) Pozzi A, Arcuri L , Block MS, Moy P Digital assisted soft tissue sculpturing technique for immediate loading pink free complete arch implant prosthesis. J Prosthodont Res 2021
(13) Pozzi A, Tallarico M, Moy P. The implant biologic pontic design interface: description of the technique and cone bean computed tomography evaluation. Clin oral Implant Related Res 2015
(14) Salama MA, Pozzi A, Adar P. The scalloped guide: a proof of concept technique for a digitally streamlined pink free full arch implant protocol. Int J Periodontics Restorative Dent 2018
(15) Esquivel J, Meda RG, Blatz MB. The impact of 3D implant position on emergence profile design. Int J Perio Resto Dent 2021
(16) Meda RG, Esquievel J. Perioprostodontic pontic site management part 1: pontic design and their current applications. J Esthet Restor Dent 2023
(17) Agnini A, Coachman C, Benedetti G, Romeo D, Weinstein T, Agnini An. Copy-paste concept: Full digital approach in the management of gingival emergence profiles. J Esthet Restor Dent 2023
(18) Revilla LM, Kois JC. A guide for selecting the intra oral scan extension when fabricating tooth and implant supported fixed dental prostheses. J Esthet Restorative Dent 2024
(19) Bidra AS, Rungruanganunt P, Gauthier M.Clinical outcomes of full arch fixed implant-supported zirconia prostheses: A systematic review. Eur J Oral Implantol 2017
(20) Nedelcu R, Olsson P, Nystrom I, Thor A. Finish line distinctness and accuracy in 7 intra oral scanners versus conventional impression: an in vitro descriptive comparison. BMC Oral Health 2018
(21) Ozcan M,Hammerle C. Titanium as a reconstruction and implant material in dentistry: advantages and pitfalls in dentistry. Materials 2012
(22) Scarano A. Zirconia crowns cemented on titanium bars using Cad Cam: a five year follow up prospective clinical study of 9 patients. Bmc Oral Health 2018
(23) Agnini Al, Agnini A. Digital Dental Recipe for a Smile Makeover Restoration. J Estet Dent 2020