The prototype concept in a full digital implant workflow

The Verified Intraoral Scanning Workflow for the Full Arch Implant Patient

The authors have questioned the accuracy of intraoral scanning when restoring the full arch implant patient. Yet clinicians use intraoral scanning (IOS) for this purpose due to the many efficiencies that the IOS workflow offers. This article describes a workflow that is used to enhance the accuracy of the intraoral scan without the need to use photogrammetry. It uses a design file for the provisional prototype restoration to create both a one piece prototype prosthesis and a segmented verification prosthesis. This verified workflow has the efficiency and comfort of the IOS workflow and the accuracy of the traditional workflow.

Additive manufacturing technologies in the oral implant clinic: A review of current applications and progress

Additive manufacturing (AM) technologies can enable the direct fabrication of customized physical objects with complex shapes, based on computer-aided design models. This technology is changing the digital manufacturing industry and has become a subject of considerable interest in digital implant dentistry. Personalized dentistry implant treatments for individual patients can be achieved through Additive manufacturing. Herein, we review the applications of Additive manufacturing technologies in oral implantology, including implant surgery, and implant and restoration products, such as surgical guides for implantation, custom titanium meshes for bone augmentation, personalized or non-personalized dental implants, custom trays, implant casts, and implant-support frameworks, among others. In addition, this review also focuses on Additive manufacturing technologies commonly used in oral implantology. Stereolithography, digital light processing, and fused deposition modeling are often used to construct surgical guides and implant casts, whereas direct metal laser sintering, selective laser melting, and electron beam melting can be applied to fabricate dental implants, personalized titanium meshes, and denture frameworks. Moreover, it is sometimes required to combine Additive manufacturing technology with milling and other cutting and finishing techniques to ensure that the product is suitable for its final application.

Complete Digital Workflow for Prosthesis Prototype Fabrication with Double Digital Scanning: Accuracy of Fit Assessment

PURPOSE

To assess the accuracy of a complete digital workflow protocol for fabrication of printed prosthesis prototypes for maxillary immediate loading treatment.

MATERIALS AND METHODS

A maxillary stone cast with 4 abutment-level implant analogs with adequate antero-posterior spread was fabricated. This stone cast served as a reference cast and a zirconia prosthesis was also fabricated to serve as an interim prosthesis. Double digital scanning was used for digital scans of the reference cast and the interim prosthesis, respectively. An intraoral scanner (TRIOS^® 3) was used to capture the standard tessellation language (STL) files. These STL files were then imported to computer-aided design (CAD) software (Exocad DentalCAD) and superimposed into a final design STL file that was exported to 3 different (Form 3b+, Carbon M2, Sprintray Pro95) three-dimensional (3D) printers to produce a total of 90 printed prototypes (n = 30 from each 3D printer). Two blinded clinicians assessed the accuracy of fit of each digitally fabricated prosthesis prototype on the reference cast, utilizing the screw-resistance test and radiographs. The Fisher's exact test was used to test the difference between the groups.

RESULTS

Out of the 90 digitally fabricated prototypes, 86 (95.6%) presented with accurate fit. The accuracy of fit ranged from 87% (26/30) for Sprintray Pro95 to 100% (30/30) for the Form 3b+ and M2 Carbon groups.

CONCLUSIONS

Digitally fabricated prosthesis prototypes can be generated with a complete digital workflow leading to clinically acceptable fit, while reducing the number of appointments and treatment time. The 3D printer had an effect on the accuracy of prosthesis prototype fit.

Complete Digital Workflow for Prosthesis Prototype Fabrication with the Double Digital Scanning (DDS) Technique: A Prospective Study on 16 Edentulous Maxillae

PURPOSE

To assess the accuracy of fit of milled prosthesis prototypes for completely edentulous patients using a digital workflow.

MATERIALS AND METHODS

Sixteen patients received intraoral full-arch digital scans with the double digital scanning (DDS) technique and the generated standard tessellation language (STL) files were superimposed and imported into computer-aided design software (Exocad DentalCAD, exocad GmbH, Darmstadt, Germany) for design. After the design, each master STL file was used for computer-aided manufacturing of the prosthesis prototypes through a complete digital workflow. The primary outcome was the accuracy of fit assessment of the digitally fabricated prototypes on verified patient master stone casts. Two blinded clinicians tested the accuracy of fit of the milled prosthesis prototypes on the verified master stone casts utilizing the screw-resistance test and direct observation.

RESULTS

Out of the 16 digitally fabricated prototypes from intraoral full-arch digital scans, all 16 presented with an accurate fit on verified master stone casts.

CONCLUSIONS

Digitally fabricated full-arch prosthesis prototypes can be generated with a complete digital workflow leading to clinically acceptable fit.

A Combined Digital Technique for Manufacturing Functional Fixed Implant Prosthesis Prototypes Using a CAD/CAM Software

The manufacture of complete-arch fixed implant prostheses requires many technical steps to ensure a successful outcome. With the use of monolithic materials such as zirconia, the design of the prosthesis is crucial for a superior result. The aim of this article is to outline a combined technique using a CAD/CAM software for the manufacture of fixed implant prosthesis prototypes for complete-arch implant rehabilitations, which can be done in-house with minimal equipment. This makes it accessible and feasible for those who wish to be involved in the design phase of such prostheses. The method involves collecting several 3D data files including the patient's current prosthesis, the definitive cast, occlusal records and photographs. The technique is described using a patient case that has been provided with digitally designed and in-house manufactured prototypes.

Analysis of Digital Workflow in Implantology

Digital workflow is increasingly accessible in daily dental practice. It has several benefits in implantology, such as the possibility of precise planning, which results in faster and safer surgery and, consequently, reduced prosthetic complications. There are also disadvantages that must be taken into consideration for successful treatment, such as deviations between the planned and placed implant position and intraoral scanning inaccuracies. We report a clinical case in implantology in which digital workflow was used throughout the process, pointing out its facilities and complications in the daily practice of dental surgeons. The patient had grade II mobility and external root resorption of tooth 11. After virtual planning, a surgical guide was fabricated by a CAD/CAM system, with immediate placement of a dental implant using the guided surgery technique. At the end of the osseointegration period, intraoral scanning was performed for fabrication of the final prosthesis also by a CAD/CAM system. After placement, the patient approved the aesthetic and functional results of the implant. We observed advantages such as simplification of clinical steps and safety of the proposed planning, but there were also disadvantages such as the complexity of digital tools, deviations of the placed implant, and inaccuracy in color selection. It was concluded that digital workflow is a reality that can be integrated into daily dental practice, resulting in greater safety, predictability of results, and ease of use in all clinical stages. However, it should be noted that there are still inaccuracies in digital tools and that a steep learning curve is needed in this area, which, if neglected, may lead to unsatisfactory results.

Digital workflow: In vitro accuracy of 3D printed casts generated from complete-arch digital implant scans

STATEMENT OF PROBLEM

Data on the accuracy of printed casts from complete-arch digital implant scans are lacking.

PURPOSE

The purpose of this in vitro study was to compare the 3D accuracy of printed casts from a complete-arch digital implant intraoral scan with stone casts from conventional impressions.

MATERIAL AND METHODS

An edentulous mandibular cast with 4 multiunit abutments with adequate anteroposterior spread was used as the master cast. Digital scans (n=25) were made by using a white light intraoral scanner (IOS). The generated standard tessellation language (STL) data sets were imported into a computer-assisted design (CAD) software program to generate complete-arch implant casts through 3D printing technology. The 25 printed casts and the mandibular master cast were further digitized by using a laboratory reference scanner (Activity 880; Smart Optics). These STL data sets were superimposed on the digitized master cast in a metrology software program (Geomagic Control X) for virtual analysis. The root mean square (RMS) error and the average offset were measured.

RESULTS

When compared with the master cast, the printed casts had a mean ±standard deviation RMS error of 59 ±16 μm (95% CI: 53, 66). The maximum RMS error reached 98 μm. The average offsets were all negative, with a significant difference compared with zero (P<.001).

CONCLUSIONS

The implant 3D deviations of the printed casts from complete-arch digital scans had statistically significant differences compared with those of the master cast but may still be within the acceptable range for clinical application.