Dr. Carlo Massimo Saratti
DMD, MAS
• Diploma of Doctor of Dental Medicine at University of Florence, Italy (2011).
• Master of Advanced Studies in Microinvasive Aesthetic Dentistry at University of Geneva (2014–2016)
• Senior assistant in the division of Cariology and Endodontics in the University of Geneva
• Coordinator of post-graduate program MAS of Microinvasive Aesthetic Dentistry of the same University
• Researcher and author of several articles on international scientific journals about dental materials for restorative dentistry
• Works in the private practice at the Geneva Smile Center as specialist in esthetic adhesives restorations for single tooth and full-mouth rehabilitations, with conventional approaches and digital devices
Dr. Alireza Alipour Tehrany
introduction
introduction
The evolution of digital dentistry has profoundly reshaped clinical practice over the last decade, introducing protocols that streamline workflows, improve patient outcomes, and significantly enhance clinical efficiency. Among these innovations, chairside procedures leveraging digital workflows have rapidly emerged as particularly transformative, offering clinicians the ability to deliver high-quality restorations in significantly reduced timeframes [1]. Traditional indirect restorative protocols typically require multiple appointments and laboratory involvement, resulting in extended treatment times, increased costs, and potential discomfort for patients. In contrast, chairside digital approaches drastically condense the treatment timeline, often allowing clinicians to perform all necessary procedures—from diagnosis and digital design to fabrication and cementation—within a single appointment.
A pivotal advancement supporting these chairside efficiencies is the rapid progression of 3-dimensional (3D) printing technologies. Initially perceived as primarily suited to prototyping and auxiliary applications, recent technological advancements in materials science and printer precision have significantly expanded the clinical applications of 3D printing in restorative dentistry[2]. The current generation of dental-specific 3D printers offers unprecedented accuracy, surface quality, and mechanical properties, making them suitable for definitive restorations. Particularly, 3D-printed composite resins have emerged as a viable alternative to conventional ceramic or composite materials used in computer-aided design (CAD) and manufacturing, exhibiting favorable esthetic properties, ease of fabrication, and mechanical characteristics suitable for a broad range of restorative indications [3].
The advantages offered by 3D-printed composite materials extend beyond convenience and chairside availability. They offer excellent adaptability and ease of intraoral adjustments, thereby contributing to clinical flexibility without compromising the quality of the final restoration. The workflow integration enabled by 3D printing technology also optimizes efficiency, reduces material waste, and promotes a more sustainable and patient-friendly clinical environment. Moreover, the adaptability of these technologies allows clinicians greater freedom to customize restorations precisely to patient-specific anatomical and functional requirements, enhancing both clinical and patient-reported outcomes [4].
Despite these significant benefits, comprehensive clinical documentation and literature supporting routine clinical integration of chairside 3D-printed composites remain relatively limited. Therefore, sharing detailed case experiences becomes vital for validating and further expanding the evidence base supporting these innovative techniques.
This case report presents a detailed clinical account of 2 indirect composite restorations fabricated chairside using state-of-the-art 3D printing technology. It highlights the efficiency, reliability, and practicality that can be achieved through modern digital workflows. Specifically, it highlights how leveraging these technologies can dramatically reduce treatment times while delivering restorations that meet high standards of function, aesthetics, and comfort. By illustrating the clinical steps, digital integration process, and final outcomes, this case report reinforces the role of advanced 3D printing techniques as a valuable tool in contemporary restorative dentistry, encouraging broader adoption and ongoing innovation in daily clinical practice.
Case description
Case description
The initial clinical examination revealed 2 aging restorations on teeth 26 and 27, as documented photographically (Fig. 1).
Specifically, tooth 26 had an indirect composite restoration placed 12 years earlier, now requiring replacement due to recurrent caries localized primarily at the distal interproximal margin. Caries also affected the mesial surface of tooth 27, which further presented with mild masticatory sensitivity, likely attributable to microfractures affecting its distovestibular cusp. Despite the absence of evident parafunctional habits, the patient reported a recent traumatic biting incident involving a hard cherry pit a few months before, likely exacerbating the structural compromise.
The proposed treatment plan involved replacing these compromised restorations with 2 indirect composite restorations fabricated chairside utilizing advanced 3D printing technology. Initially, the operative field was isolated using a rubber dam to ensure optimal isolation of the operatory field (Fig. 2).
“3D-printed composite materials offer excellent adaptability and ease of intraoral adjustments, enhancing clinical flexibility without compromising the final restoration quality.”
Next, the cavity was carefully prepared, adhering to minimally invasive principles tailored specifically for indirect restorative techniques. Preparation margins were meticulously refined after adequate caries removal and cuspal coverage (Fig. 3).
Given the subgingival placement of certain cavity margins, a precise margin relocation technique was performed. Auto-matrices were adapted (Fig. 4) to facilitate margin elevation using a combination of a dental adhesive system (Optibond FL, Kerr) and flowable composite resin (Inspiro Bi2, Edelweiss; Fig. 5). After margin elevation, the cavity margins were meticulously refined to optimize the optical scanning phase (Fig. 6).
Then, digital impressions were captured using an advanced intraoral scanner (IS 3800, Dexis), ensuring accurate and detailed reproduction (Fig. 7).
The scanned data was exported in standard tessellation language (STL) format and seamlessly integrated into dedicated chairside CAD software (Exocad Chairside). The indirect restorations were digitally designed in a streamlined chairside workflow (Fig. 8).
Upon completion of the digital design, the restorations’ STL files were re-exported and imported into specialized 3D printing software (Nauta Photoshade [version 1.6.1], Dfab). The restorations were strategically positioned on the printing platform to leverage the Photoshade technology, creating an optimal color gradient transitioning from shades A1 coronally to A3 cervically, closely mimicking natural tooth aesthetics (Fig. 9).
The restorations were printed using a hybrid composite resin formulated explicitly for dental 3D printing applications (Irix Max Photoshade A Size S cartridge, DWS Systems). The printing process was completed efficiently within approximately 20 minutes (Fig. 10).
Post-printing procedures involved rigorous surface cleaning protocols recommended by the manufacturer. The restorations underwent an initial ethanol bath to remove residual uncured resin, followed by a secondary photo-thermal curing cycle in a dedicated polymerization unit for 10 minutes, ensuring optimal material properties and biocompatibility (Fig. 11). Then, they underwent an extensive polishing protocol using the manufacturer-provided finishing kit (Dfab 3D Course Kit, EVE), delivering restorations with an ideal surface texture (Figs. 12–14).
The cementation phase began by sandblasting the dental surfaces with 27-micron aluminum powder (Fig. 15) and then etching them with 37% orthophosphoric acid for 30 seconds, achieving ideal conditioning for adhesive bonding (Fig. 16). A 3-step adhesive system (Optibond FL, Kerr) was meticulously applied on the tooth preparations (Figs. 17–18).
Simultaneously, the internal surfaces of the indirect restorations were conditioned to optimize adhesive integration, which included sandblasting (Fig. 19), application of silane coupling agent (Fig. 20), and subsequent coating with the adhesive system (Fig. 21). For cementation, a preheated microhybrid composite resin (Inspiro Bi2, Edelweiss) was employed due to its favorable mechanical and aesthetic characteristics. The restorations were accurately seated onto their respective tooth preparations, aided by high-frequency ultrasonic tips to facilitate complete adaptation and displacement of excess luting material (Fig. 22).
Excess material was meticulously removed using probes and dental floss to ensure clean margins. Then, the restorations were photopolymerized for 20 seconds per surface, ensuring complete polymerization and optimal bonding strength (Fig. 23).
Final polishing steps were performed under rubber dam isolation, which enhanced the restoration’s smoothness and marginal integrity (Fig. 24).
Following the removal of the rubber dam, thorough occlusal evaluations were performed, adjusting the restorations to ensure perfect harmony with the patient’s occlusal scheme, thereby ensuring functional comfort and long-term durability (Fig. 25).
discussion and conclusion
discussion and conclusion
The integration of advanced chairside digital workflows, particularly those utilizing 3D printing technologies, represents a significant advancement in restorative dentistry, offering remarkable benefits in terms of efficiency, precision, and patient experience.
The presented clinical case effectively highlights these advantages, showing the successful chairside fabrication and delivery of 2 indirect composite restorations using the innovative Dfab 3D printer system.
One of the primary advantages of the chairside approach is the considerable reduction in treatment duration, which has traditionally been a major limitation in indirect restorative procedures. Conventionally, indirect restorations require multiple clinical visits and extensive laboratory involvement, inherently increasing time, cost, and inconvenience for patients. As illustrated in the presented case, the chairside workflow consolidates the entire restorative process—from cavity preparation and digital impression to restoration fabrication and cementation—into a single clinical session, significantly streamlining practice efficiency and patient convenience.
“3D-printed composite resins have emerged as a viable alternative to conventional CAD/CAM materials.”
The use of 3D printing technology further amplifies these benefits. Modern dental-specific 3D printers, exemplified by the Dfab system used in the presented case, offer exceptional precision and reliability, which are essential for creating restorations with an accurate fit and excellent functional and aesthetic properties. The Dfab printer demonstrated high performance through its rapid printing capabilities and consistent production of restorations that accurately replicated the digitally designed anatomy. This precision not only facilitated an easier clinical integration phase but also ensured optimal restoration adaptation, minimizing chairside adjustments and enhancing overall treatment predictability. The Photoshade technology incorporated into the Dfab system also provided distinct aesthetic advantages, allowing the creation of restorations with a natural color gradient. Such capability is particularly beneficial in everyday clinical practice, offering clinicians enhanced control over aesthetic outcomes.
While further studies and long-term clinical observations remain necessary to reinforce and expand the evidence supporting the routine adoption of 3D-printed composite restorations, the outcomes documented in this case report are highly encouraging. The demonstrated clinical reliability, precision, and operational simplicity of the Dfab printer affirm its substantial potential in contemporary restorative dentistry. Continued advancements in 3D printing materials and technology will undoubtedly further extend these benefits, potentially establishing chairside 3D printing as a new standard in everyday dental practice.
sources
(1) F Del Curto, CM Saratti, I Krejci. CAD/CAM-based chairside restorative technique with composite resin for full-mouth adhesive rehabilitation of excessively worn dentition. Int J Esthet Dent 2018;13(1):50-64.
(2) CM Saratti, GT Rocca, I Krejci. The potential of three-dimensional printing technologies to unlock the development of new ‘bio-inspired’ dental materials: an overview and research roadmap. J Prosthodont Res 2019 Apr;63(2):131-139.
(3) FG Mangano, D Cianci, N Pranno, H Lerner, F Zarone, O Admakin. Trueness, precision, time-efficiency and cost analysis of chairside additive and subtractive versus lab-based workflows for manufacturing single crowns: An in vitro study. J Dent 2024 Feb:141:104792.
(4) A Alammar, W Att, F Beuer. The Accuracy of 3D-Printed Fixed Dental Restorations. J Esthet Res-tor Dent 2024 Dec 8. doi: 10.1111/jerd.13365.