Rehabilitation of a maxillectomy patient using intraoral scanning impression technology and a computer-aided design/computer-aided manufacturing fabricated obturator prosthesis: A clinical report

Rehabilitation of Combined Hard and Soft Palate Defects with a Soft Relining Prosthesis: A Clinical Report

It remains a significant challenge in prosthetic rehabilitation for combined hard and soft palate defects on account of two primary reasons. At first, conventional impressions can hardly get an accurate analogue and usually bring about a terrible experience for the patients. Secondly, conventional hard denture base resins used in obturator prostheses exhibit limitations in marginal sealing, undercut retention, and elastic buffering when in contact with the soft palate. This article presents a case where combined hard and soft palate defects were successfully and rapidly reconstructed by using digital intraoral impression technology and denture soft reline material.

Digital workflow feasibility for the fabrication of intraoral maxillofacial prosthetics after surgical resection: a systematic literature review

OBJECTIVES

To evaluate the current evidence of digital workflow feasibility based on the data acquisition methods and the software tools used to fabricate intraoral prostheses for patients with partial or total maxillary and mandibular defects.

MATERIALS AND METHODS

An electronic search was performed in PubMed, SCOPUS, and Web of Science using a combination of relevant keywords: digital workflow, digital designing, computer-assisted design-computer aided manufacturing, 3D printing, maxillectomy, and mandibulectomy. The Joanna Briggs Institute Critical Appraisal Tool was used to assess the quality of evidence in the studies reviewed.

RESULTS

From a total of 542 references, 33 articles were selected, including 25 on maxillary prostheses and 8 on mandibular prostheses. The use of digital workflows was limited to one or two steps of the fabrication of the prostheses, and only four studies described a complete digital workflow. The most preferred method for data acquisition was intraoral scanning with or without a cone beam computed tomography combination.

CONCLUSION

Currently, the fabrication process of maxillofacial prostheses requires combining digital and conventional methods. Simplifying the data acquisition methods and providing user-friendly and affordable software may encourage clinicians to use the digital workflow more frequently for patients requiring maxillofacial prostheses.

Combined digital-conventional workflow to fabricate a definitive obturator from an interim obturator for a patient with an anterior maxillectomy defect

An existing interim obturator can be reproduced as the definitive one using digital technology, with benefits for a patient with a maxillectomy. By digitally scanning the oral condition and the existing interim obturator, a definitive obturator, including a computer-aided designed and computer-aided manufactured metal framework, was fabricated and delivered to a patient with an anterior maxillectomy defect by following a combined digital and conventional workflow. This technique can hasten the adaptation of the patient to the new obturator and ensure a more comfortable and safer clinical procedure.

Digital workflow and virtual validation of a 3D-printed definitive hollow obturator for a large palatal defect

This clinical report describes how a hollow obturator prosthesis was designed and fabricated for an 82-year-old partially edentulous patient with a large palatal defect. Computer-aided design (CAD) was used to design, articulate, and align the mandibular denture with the obturator prosthesis. The prosthesis was printed, adjusted chairside, rescanned, and made hollow by using a CAD software program. The prosthesis was printed in resin with a dental 3D printer. Quantitative evaluations of clinical (prosthesis dimensions, rest, and occlusal vertical dimensions) and virtual (surface area, volume, weight, interpoint mismatches, spatial overlap) parameters found that the 3D-printed prosthesis required an additional 5% chairside modification. The greatest differences in volume (24.7% less) and weight (22.2% less) were observed when the modified obturator bulb was made hollow via CAD. Hollowing the bulb, therefore, reduced the spatial overlap in volume by 16.8%.

Clinical Applications of Intraoral Scanning in Removable Prosthodontics: A Literature Review

PURPOSE

This review aimed to identify the reported intraoral scanning applications in fabricating different types of removable prostheses in the field of prosthodontics.

METHODS

A comprehensive electronic search was performed using the PubMed and MEDLINE databases. This review included in vitro studies and clinical reports published between January 2013 and March 2021. The main keywords were as follows: intraoral scanning, digital impression, computerized digital impression, removable prosthesis, chairside computer-aided design/computer-assisted manufacturing, digital complete denture, digital immediate complete denture, digital interim complete denture, digital removable partial denture, digital removable overdenture, digital obturator, digital occlusal splints, and digital maxillofacial prostheses.

RESULTS

In total, 33 papers (22 clinical reports, 8 papers focused on dental techniques, and 3 clinical studies) were included in the final analysis.

CONCLUSIONS

The efficiency of using intraoral scanning in the field of removable prosthodontics was documented. However, there is a need for more clinical studies to identify intraoral scanning-usage protocols and to yield reliable and valid data.

The direct digital workflow in fixed implant prosthodontics: a narrative review

BACKGROUND

The purpose of this narrative review was to examine the applicability of IOS procedures regarding single and multiple fixed implant restorations. Clinical outcomes for monolithic zirconia and lithium disilicate restorations produced through a direct digital workflow were reported.

METHODS

A MEDLINE (Pubmed) search of the relevant English-language literature spanning from January 1st 2015 until March 31st 2020 was conducted. In vitro studies comparing digital implant impression accuracy by different IOS devices or in vitro studies examining differences in accuracy between digital and conventional impression procedures were included. Also, RCTs, clinical trials and case series on the success and/or survival of monolithic zirconia and lithium disilicate restorations on implants, manufactured completely digitally were included. In vitro and in vivo studies reporting on restorations produced through an indirect digital workflow, case reports and non-English language articles were excluded. The aim was to investigate the accuracy of IOS for single and multiple fixed implant restorations compared to the conventional impression methods and report on the variables that influence it. Finally, this study aimed to report on the survival and success of fixed implant-retained restorations fabricated using the direct digital workflow.

RESULTS

For the single and short-span implant sites, IOS accuracy was high and the deviations in the position of the virtual implant fell within the acceptable clinical limits. In the complete edentulous arch with multiple implants, no consensus regarding the superiority of the conventional, splinted, custom tray impression procedure compared to the IOS impression was identified. Moreover, complete-arch IOS impressions were more accurate than conventional, non-splinted, open or close tray impressions. Factors related to scanbody design as well as scanner generation, scanning range and interimplant distance were found to influence complete-arch scanning accuracy. Single implant-retained monolithic restorations exhibited high success and survival rates and minor complications for short to medium follow-up periods.

CONCLUSIONS

The vast majority of identified studies were in vitro and this limited their clinical significance. Nevertheless, intraoral scanning exhibited high accuracy both for single and multiple implant restorations. Available literature on single-implant monolithic restorations manufactured through a complete digital workflow shows promising results for a follow-up of 3-5 years.

Digital Workflow in Maxillofacial Prosthodontics—An Update on Defect Data Acquisition, Editing and Design Using Open-Source and Commercial Available Software

Background: A maxillofacial prosthesis, an alternative to surgery for the rehabilitation of patients with facial disabilities (congenital or acquired due to malignant disease or trauma), are meant to replace parts of the face or missing areas of bone and soft tissue and restore oral functions such as swallowing, speech and chewing, with the main goal being to improve the quality of life of the patients. The conventional procedures for maxillofacial prosthesis manufacturing involve several complex steps, are very traumatic for the patient and rely on the skills of the maxillofacial team. Computer-aided design and computer-aided manufacturing have opened a new approach to the fabrication of maxillofacial prostheses. Our review aimed to perform an update on the digital design of a maxillofacial prosthesis, emphasizing the available methods of data acquisition for the extraoral, intraoral and complex defects in the maxillofacial region and assessing the software used for data processing and part design. Methods: A search in the PubMed and Scopus databases was done using the predefined MeSH terms. Results: Partially and complete digital workflows were successfully applied for extraoral and intraoral prosthesis manufacturing. Conclusions: To date, the software and interface used to process and design maxillofacial prostheses are expensive, not typical for this purpose and accessible only to very skilled dental professionals or to computer-aided design (CAD) engineers. As the demand for a digital approach to maxillofacial rehabilitation increases, more support from the software designer or manufacturer will be necessary to create user-friendly and accessible modules similar to those used in dental laboratories.

Frequency and type of digital procedures used for the intraoral prosthetic rehabilitation of patients with head and neck cancer: A systematic review

STATEMENT OF PROBLEM

In spite of a digital workflow playing an important role in the intraoral prosthetic rehabilitation of patients with head and neck cancer, information about how it has been implemented and its clinical implications is sparse.

PURPOSE

The purpose of this systematic review was to evaluate the use of a digital workflow in the intraoral prosthetic rehabilitation of patients with head and neck cancer by analyzing the frequency and type of the digital procedures used.

MATERIAL AND METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. The following terms were applied for the search conducted in the MEDLINE-PubMed, Cochrane, and SciELO databases: (prosthesis OR dental OR rehabilitation) AND (digital OR CAD-CAM OR intraoral scanner) AND (Cancer OR head neck). Articles that specified data on intraoral prosthetic treatment and analyzed the use of a digital workflow in the different prosthetic phases such as digital scanning and computer-aided design and computer-aided manufacturing (CAD-CAM) in patients with head and neck cancer were included. Data from the frequency and type of digital procedures were analyzed.

RESULTS

Thirteen articles were included, and all had incorporated CAD-CAM techniques in at least 1 of the prosthetic treatment stages (scanning, design, and/or fabrication). Only 1 patient was rehabilitated by using a completely digital workflow. The most frequent prosthetic treatment was an obturator (82.6%). Regarding the image capture method, the most used method was cone beam computed tomography (CBCT) (60.9%).

CONCLUSIONS

Most reports described the partial use of a digital workflow in the intraoral prosthetic rehabilitation of patients treated for head and neck cancer. A digital workflow is used for specific stages but not for the entire process. More studies are needed to evaluate digital systems, ideally comparing parameters with the conventional method, and to determine whether this technique has more relevant clinical implications.

Rapid additive manufacturing of an obturator prosthesis with the use of an intraoral scanner: A dental technique

A protocol for a completely digital manufacturing process for an obturator prosthesis is described. An intraoral scanner was used to capture the mandible and maxilla together with the sinus defect. The obturator base and the artificial teeth were created with a computer-aided design software program and manufactured by 3-dimensional printing. Stainless steel clasps provided the retention for the prosthesis.