Dental Techniques
Virtual 3-dimensional representation of a completely edentulous patient for computer-aided static implant planning
A technique is described to create a virtual 3-dimensional representation of an edentulous patient by aligning the facial, intraoral, and cone beam computed tomography scans guided by an additively manufactured scan body. Having the virtual patient facilitated the prosthetically driven implant planning, the additive manufacturing of the surgical implant guides, and the interim dental restorations.A technique to fabricate a custom CAD-CAM periapical radiographic film holder for implant assessment
Standardized radiographs produced by using the paralleling technique play an important role in monitoring prosthetic misfit and marginal bone levels around endosseous implants. Under clinical conditions, parallel adjustment of the film with respect to the implant requires the use of positioning devices. This article describes the fabrication of a custom computer-aided design and computer-aided manufacturing (CAD-CAM) device suitable for implants adjacent to natural teeth.A device to facilitate separation of components of combined screw- and cement-retained implant-supported crowns
This article describes a technique to separate parts of cemented implant-supported restorations with a screw hole. A device was designed by using a computer-aided design (CAD) program and was milled in a milling center. The restoration was heated to 400 °C and then subjected to controlled mechanical force with the help of the device to separate the cemented parts.Digital verification and correction of digital intraoral scans for fixed implant rehabilitation of edentulous arches: A dental technique
A method is described for the verification and correction of a digital scan of a complete arch implant-supported prosthesis for a completely edentulous patient. The technique provides an efficient way to integrate a highly accurate and precise scan of an implant index cast with a digital intraoral implant scan by using a computer-aided design and computer-aided manufacturing (CAD-CAM) software program. This method allows dental professionals to validate and, if necessary, correct the implant positions in the scan without the need for a conventional impression.Cast-free fabrication of a digital removable partial denture with a polyetheretherketone framework
Digital workflows for removable partial dentures have enabled new machinable framework materials, including polyetheretherketone (PEEK). In addition, all denture components can be designed and manufactured digitally. Nonetheless, physical casts are still required for assembly of the components. The adoption of a cast-free fabrication procedure may enhance benefits, including a reduced number of procedures, faster processing, and reduced material waste. The purpose of this technical report was to demonstrate a workflow for the fabrication of a removable partial denture with a PEEK framework, milled teeth, and milled flanges, which uses intraoral scanning and no physical casts.Automated vector analysis to design implant-supported prostheses: A dental technique
The prosthesis loading force is an important factor for dental implant survival. Even if adequate osseointegration of the dental implant has been achieved, if the occlusal forces are not correctly distributed, lateral torque can be generated causing high stress on surrounding tissues. The stress value of implant prostheses could be different whether the direction of load is vertical or oblique, affected by the shape of the occlusal surface. When an implant-supported prosthesis is designed with a dental computer-aided design software program, the average vectors from each occlusal contact point can be visualized.Retrofitting of an implant-supported surveyed crown under an existing removable partial denture by using an acrylic resin template
Retrofitting a crown to an existing removable partial denture (RPD) is a complex process and requires additional clinical and laboratory procedures. Various methods have been described for retrofitting a new tooth-supported crown. However, if an abutment tooth has to be extracted, descriptions of techniques for restoring a new edentulous site with an implant-supported crown retrofitted to an existing RPD are lacking. Therefore, this technical report describes a straightforward approach to fabricating an implant-supported surveyed crown fitted to an existing RPD by using an acrylic resin template.Assessing the accuracy of fabricated implant surgical guides by reconstructing the implant position based on cone beam computed tomography images: A dental technique
A protocol for qualitatively reviewing the accuracy of fabricated implant surgical guides is presented. Once these guides have been inserted and fixed intraorally, cone beam computed tomography (CBCT) scans are made. Implant positions can be recalculated by processing the series of sleeve images on the CBCT scans. This protocol offers an opportunity for double-checking the accuracy of a fabricated guide before surgery in certain circumstances.Partially digital workflow for making complete-arch implant-supported fixed prostheses: A dental technique
This article describes a technique for making complete-arch implant-supported fixed prostheses by using intraoral scanning and computer-aided design and computer-aided manufacturing (CAD-CAM) technology for the fabrication of a metal substructure and conventional processing for the prosthesis base. For this, a device was designed to accurately capture the position of multiple implants and the associated digitalized surgical guide, and the metal substructure was planned and milled directly in cobalt-chromium.Silicone key device for maxilla orientation and occlusal plane recording in a digital workflow
This article describes a technique for recording the maxilla’s orientation in esthetically driven oral rehabilitation and transferring its position by using computer-aided design and computer-aided manufacturing (CAD-CAM) technology. The protocol uses a Fox plane and a bubble level to orient an addition silicone key of the maxilla parallel to the occlusal reference plane. The silicone reference key was scanned, superimposed over the maxilla intraoral standard tessellation language (STL) file, and adequately oriented in a CAD software program.A diagnostically and digitally driven tooth preparation protocol by using a patient monitoring tool with an intraoral scanner
Finding the right balance between the preservation of tooth structure and providing adequate space for the restorative material is a major challenge in prosthetic dentistry. A technique is presented using the patient monitoring tool available in standard software programs of an intraoral scanner to constantly monitor preparation dimensions in relation to the optimal definitive restoration.Digitally designed reduction guide to correct proclined anterior teeth: An aid before fabricating trial restorations
Restoring teeth with ceramic laminate veneers is most often an additive procedure. However, when proclined anterior teeth are being treated, a misfitting silicone matrix will lead to inaccurate trial restorations, affecting evaluation of the definitive esthetic result and leading to inaccurate definitive preparations. Using the digital technology, a 3-dimensionally printed reduction guide can be used to remove the proclined areas as the first step before trial restorations. Then, the trial restorations and made and then the definitive preparations made through them.A multifunctional guided surgery to assist in the 3-dimensional positioning of dental implants and in obtaining a palatal gingival graft
Parameters such as the correct 3-dimensional positioning and the quality of peri-implant soft tissues are fundamental to the success of implant-supported restorations. Digital planning and guided surgery techniques can make the implant placement more accurate, and modifying the periodontal phenotype is often fundamental to increasing esthetics and peri-implant health, mainly in esthetic areas. This article describes a guided surgery technique that assists in the 3-dimensional positioning of implants and identifies the best anatomic area (volume and safety) for obtaining a palatal gingival graft.Additively manufactured scan body for transferring a virtual 3-dimensional representation to a digital articulator for completely edentulous patients
A technique is described for obtaining a virtual 3-dimensional representation of completely edentulous patients with the virtual definitive casts mounted on the virtual articulator. An additively manufactured intraoral scan body was developed to record the definitive maxillary and mandibular casts and gothic arch interocclusal registration. The intraoral scan body guided the integration of the digital definitive casts and facial scans to obtain the virtual 3-dimensional patient’s representation and facilitated the transfer of the definitive casts to the virtual articulator.Fabrication of a complete-arch implant-supported fixed interim prosthesis by using a cone beam computed tomography digital scan for a patient with primordial dwarfism: A dental technique
A complete-arch implant-supported interim prosthesis was fabricated from a cone beam computed tomography digital scan of the implant abutments for a patient with primordial dwarfism. The patient presented with limited mouth opening, which hindered the use of a conventional impression technique. The described technique provided an alternative digital procedure to obtain a virtual implant definitive cast.The patient-specific anatomical articulator
Currently available dental articulators have limitations for reproducing human mandibular movements. The present article describes an innovative device that is a true patient-specific anatomical articulator that accurately simulates patient anatomy and eliminates all technique-sensitive mounting procedures, thus substantially diminishing potential errors in mounting and articulator settings. By using three-dimensional (3D) printing technology, patient cone beam computed tomography (CBCT) data are used to print 3D replicas of the condylar fossae, as well as the actual condyles, at the correct intercondylar distance.Dynamic and static computer-guided surgery using the double-factor technique for completely edentulous patients: A dental technique
A novel computer-assisted surgery (CAS) technique that merges dynamic and static CAS approaches to treat completely edentulous patients with dental implants is described. Radiographic and surgical stents are designed with specific fiducial markers that are recognized by the static and dynamic CAS software program. During the surgical procedure, implants are placed following the static surgical guide and the indications from the dynamic navigation system. This technique combines the advantages of static and dynamic CAS approaches to allow accurate and predictable minimally invasive implant placement.Combined bone- and mucosa-supported 3D-printed guide for sinus slot preparation and prosthetically driven zygomatic implant placement
The use of zygomatic implants to rehabilitate the severely atrophic maxilla has been well documented since first being introduced by Brånemark. Placement of zygomatic implants is technically complex, with catastrophic complications and numerous prosthetic challenges resulting from imprecise placement. The purpose of this report was to demonstrate a technique that allows transfer of the preoperatively planned sinus slot position to the surgical field by using cone beam computed tomography (CBCT) and an implant planning software program to fabricate a combined bone- and mucosa-supported 3D-printed surgical guide.Transferring the finish line of an interim restorative to the definitive cast in biologically oriented preparation technique (BOPT) procedures: A dental technique
The biologically oriented preparation technique (BOPT) uses a vertical tooth preparation and simultaneously a controlled rotary instrumentation of the gingival sulcus. The resulting blood clot is stabilized with the interim restoration. However, accurate transfer of the emergence profile of the interim crown to the definitive restoration is essential to maintain the gingival architecture. This technique article describes clinical and laboratory procedures to predictably transfer the emergence profile of the interim crown to duplicate the gingival architecture in the definitive restoration.Multipurpose application of custom, rigid, clear matrix for fabricating trial restorations, tooth preparation guides, and interim veneers
Interim veneers present an esthetic and functional challenge for restorative dentists. Moreover, inadequate fit or trauma to the soft tissue during their fabrication or subsequently may affect soft-tissue health and stability and lead to bleeding that will compromise the adhesive cementation of the definitive ceramic veneers. This article describes a technique for the atraumatic fabrication of interim veneers with a custom, rigid, clear matrix designed for multipurpose use during the patient’s restorative care.Fabricating a dual-material, vat-polymerized, additively manufactured static implant surgical guide: A dental technique
Protocols with static computer-aided implant placement provide more tangible clinical advantages than conventional implant placement methods. A technique to manufacture a dual-material implant surgical guide by using a vat-polymerization printer is described. The implant surgical guide combined a resilient intaglio and hard exterior surface. The technique should minimize the clinical adjustments needed to ensure fit and improve patient comfort.Occlusal marking film for accurate interference assessments of removable partial denture frameworks: A dental technique
A technique is described for detecting areas of interference for removable partial denture frameworks. An occlusal marking film is placed between the misfitted abutment teeth and framework region. Gentle pressure is applied to seat the framework, and the exact areas of interference are seen on removal. With this clean, rapid, cost-effective, and straightforward approach, areas of interference can be precisely adjusted for complete seating of the removable partial denture framework.Interimplant papilla reconstruction at second-stage surgery: A technique
Reconstructing an esthetic interimplant papilla remains challenging with implant-supported restorations, especially for patients with a thin gingival biotype. This technique report describes a modified approach to rebuilding an interimplant papilla by joining 2 elevated connective tissue flaps at the second-stage surgery.Stone verification device for verifying the definitive cast of an implant-supported restoration: A dental technique
To reduce the risk of implant and prosthetic complications, implant-supported prostheses should be passive. A verification device is used to verify the abutment analog position on the definitive cast, and hence its accuracy. This article describes the fabrication of a Type IV stone implant verification device for verifying the accuracy of the definitive cast.Guided implant surgery workflow in edentulous patients: A precise and rapid technique
A new technique of guided implant surgery is presented. A conventional complete denture is converted into both tomographic and surgical guides and later into an interim implant-supported fixed prosthesis. A plate derived from a computed tomography scan becomes the physical link between the virtual planning and tube positioning device. Furthermore, the interim placement of mini-implants adjacent to the symphysis region stabilizes the guide throughout the guided surgery. This technique reduces treatment time and costs.
