Present and future of extraoral maxillofacial prosthodontics: Cancer rehabilitation.

Historically, facial prosthetics have successfully rehabilitated individuals with acquired or congenital anatomical deficiencies of the face. This history includes extensive efforts in research and development to explore best practices in materials, methods, and artisanal techniques. Presently, extraoral maxillofacial rehabilitation is managed by a multiprofessional team that has evolved with a broadened scope of knowledge, skills, and responsibility. This includes the mandatory integration of different professional specialists to cover the bio-psycho-social needs of the patient, systemic health and pathology surveillance, and advanced restorative techniques, which may include 3D technologies. In addition, recent digital workflows allow us to optimize this multidisciplinary integration and reduce the active time of both patients and clinicians, as well as improve the cost-efficiency of the care system, promoting its access to both patients and health systems. This paper discusses factors that affect extraoral maxillofacial rehabilitation's present and future opportunities from teamwork consolidation, techniques utilizing technology, and health systems opportunities.

Color translation from monoscopic photogrammetry +ID Methodology into a Polyjet final 3D printed facial prosthesis.

Background: The artistic techniques necessary to fabricate facial prostheses mainly depend on individual skill and are not a resource easily reproduced. Digital technology has contributed to improved outcomes, often combining analog and new digital techniques in the same workflow. Methods: This article aims to present an innovative workflow to produce a final colored 3D printed and facial prosthesis by UV-map color translation into colored resin 3D printing. A modified +ID Methodology was used to obtain 3D models with the calibrated 3D printable patient's skin color. No hands-on physical molding, manual sculpture, or intrinsic silicone coloration was used. Results: The outcome resulted in acceptable aesthetics, adaptation, and an approximate color match after extrinsic coloration. The patient reported good comfort and acceptance. Conclusions: A direct resin 3D printed prosthesis may be a viable alternative, especially for rapid delivery as an immediate prosthesis or an option when there is no experienced anaplastogist to manufacture a conventional prosthesis.

State of the Art Care in Computer-Assisted Facial Prosthetic Rehabilitation.

ABSTRACT: Autologous reconstruction for major facial defects is primarily considered for patient's lifetime care. There are situations, however, when autologous reconstruction is not ideal or feasible, and prosthetic reconstruction is necessary to reconstruct missing anatomy or to complement surgical reconstruction. The history of facial prosthetic reconstruction can be traced for millennia. At our craniofacial center, craniomaxillofacial prosthetic rehabilitation has been incorporated in the care provided to our patients since the center's inception, more than 70 years ago.The purpose of this review is to present the evolution of our current thinking based on our long experience since the implementation of computer-assistive technologies over 15 years ago, to further improve our patients' overall rehabilitation.These applications include all stages of prosthetic care from planning, design through device delivery, and for lifetime maintenance. The collaboration among surgeons and anaplastologists is fundamental to achieving optimal patient outcomes and in the success of our technology-based practice. Such collaboration starts with the patient's decision to proceed with prosthetic rehabilitation and continues with postoperative care and lifetime management of the patient's prosthetic device and prosthesis-bearing soft tissue.Although computer-assistive techniques often represent a substantial financial investment, the benefits of using them demonstrate clear advantages to both the clinician and patient. These benefits include: Improved predictability of outcomes, surgeon preparedness, reduction in operating room time, reduction in overall treatment times, improved precision and anatomical accuracy, improved treatment efficiencies, and overall treatment experience, particularly for those patients traveling great distances for access to care.Representative examples will be presented.

Smartphone Application as a Low-Cost Alternative for Digitizing Facial Defects: Is It Accurate Enough for Clinical Application?

PURPOSE: To evaluate the accuracy of a smartphone application as a low-cost approach for digitizing a facial defect for 3D modeling. MATERIALS AND METHODS: A stone model of a facial defect was scanned using industrial computed tomography (reference scan) and was also scanned five times using a commercial laser scanner. A series of 24 sequenced digital photographs was taken five times by smartphone at two elevations. These images were uploaded and processed by a cloud-based server to create virtual 3D models. The 3D datasets were geometrically evaluated and compared to the reference data using 3D evaluation software. Mann-Whitney U test was used for statistical analysis, and the significance was set at P < .05. RESULTS: The overall mean 3D deviation ± standard deviation for the smartphone dataset was 604.9 ± 123.5 µm compared to 67.5 ± 0.49 µm for the laser scanner. There was a significant difference in the accuracy between the commercial laser scanner and the smartphone application (P = .009). CONCLUSION: The results showed that within the limits of this study and in reference to standard computed tomography imaging, data acquisition with a smartphone for 3D modeling is not as accurate as commercially available laser scanning.

Virtual Surgical Planning and Three-Dimensional Printed Guide for Soft Tissue Correction in Facial Asymmetry.

Fat grafting has become a well-accepted surgical modality to correct soft tissue facial defects and asymmetries with overall good results. Several techniques have been reported over the last few years to assist in improving accurate evaluation of facial defects and in the preoperative planning of the reconstruction. Such techniques include among others, computer tomography, three-dimensional (3D) photogrammetry, high resolution ultrasound, and 3D laser scanning. There are advantages and disadvantages for each technique.With the rapid advance of 3D technologies that have become readily available to clinicians, new clinical applications continually emerge to guide and facilitate reconstructive procedures. The authors explored the possibility of fabricating a 3D printed surgical guide to define volume differences for soft tissue reconstruction in patients with facial asymmetry. The model was developed through the authors' virtual surgical simulation and planning system that consists of computer-assisted design (CAD) and 3D printing (3DP).Three-dimensional volumetric scans of patients' faces were analyzed with computer-aided design to quantify areas of facial asymmetry. Surgical guides with containers defining volumetric differences were fabricated using 3D printing to identify and quantify areas of soft tissue deficiency. The 3D printed patient-specific, guides were sterilized and used by the surgeon intraoperatively to accurately mark the areas of soft deficiency. Thus, facial symmetry was achieved by fat grafting the predetermined volume differences defined in the surgical guides. A postop mask was used by the surgeon at the end of the procedure and during follow-up clinic visit to verify and evaluate accurate fat grafting placement as well as to determine areas where to add volume if needed.This paper details the rational for the authors' approach, outlines the technical planning and fabrication process of these patient-specific custom surgical guides with quantified volumetric containers and their intraoperative use by the surgeon. Despite the authors' limited experience we conclude that the authors' technique offer surgeons a precise means for accurate volumetric reconstruction of facial asymmetry.

Subtotal Nasal Reconstruction Using a Custom 3-Dimensional Porous Polyethylene Construct.

Subtotal loss of the nose is a devastating occurrence. Traditional approaches to reconstruction have employed techniques that sequentially restore the nasal lining, support and external cover using autologous tissues. The results can be quite variable and are heavily weighted on surgical experience and expertise. We report a case of subtotal nasal reconstruction using a computer generated, 3-D printed porous polyethylene (PPE) scaffold. The patient is a 64-year-old man who presented with a sub-total nasal defect following excision of recurrent basal cell carcinoma. The missing parts comprised the distal half of the composite nose including the nasal floor and lining. The replacement nose was constructed on the patient's right radial forearm. A computer generated PPE nasal scaffold was prelaminated with a forearm flap for lining and a free temporal fascial flap and skin graft for external cover. Following healing, nostrils were created and the nasal construct was then microsurgically transferred to the face. At 18 months post-op, the reconstructed nose has remained stable and functional with excellent aesthetic appearance. The implications for use of 3-D scaffolds for composite nasal reconstruction are enormous.

Virtual surgical planning and 3D printing in prosthetic orbital reconstruction with percutaneous implants: a technical case report.

Osseointegrated titanium implants to the cranial skeleton for retention of facial prostheses have proven to be a reliable replacement for adhesive systems. However, improper placement of the implants can jeopardize prosthetic outcomes, and long-term success of an implant-retained prosthesis. Three-dimensional (3D) computer imaging, virtual planning, and 3D printing have become accepted components of the preoperative planning and design phase of treatment. Computer-aided design and computer-assisted manufacture that employ cone-beam computed tomography data offer benefits to patient treatment by contributing to greater predictability and improved treatment efficiencies with more reliable outcomes in surgical and prosthetic reconstruction. 3D printing enables transfer of the virtual surgical plan to the operating room by fabrication of surgical guides. Previous studies have shown that accuracy improves considerably with guided implantation when compared to conventional template or freehand implant placement. This clinical case report demonstrates the use of a 3D technological pathway for preoperative virtual planning through prosthesis fabrication, utilizing 3D printing, for a patient with an acquired orbital defect that was restored with an implant-retained silicone orbital prosthesis.

Monoscopic photogrammetry to obtain 3D models by a mobile device: a method for making facial prostheses.

PURPOSE: The aim of this study is to present the development of a new technique to obtain 3D models using photogrammetry by a mobile device and free software, as a method for making digital facial impressions of patients with maxillofacial defects for the final purpose of 3D printing of facial prostheses. METHODS: With the use of a mobile device, free software and a photo capture protocol, 2D captures of the anatomy of a patient with a facial defect were transformed into a 3D model. The resultant digital models were evaluated for visual and technical integrity. The technical process and resultant models were described and analyzed for technical and clinical usability. RESULTS: Generating 3D models to make digital face impressions was possible by the use of photogrammetry with photos taken by a mobile device. The facial anatomy of the patient was reproduced by a *.3dp and a *.stl file with no major irregularities. 3D printing was possible. CONCLUSIONS: An alternative method for capturing facial anatomy is possible using a mobile device for the purpose of obtaining and designing 3D models for facial rehabilitation. Further studies must be realized to compare 3D modeling among different techniques and systems. CLINICAL IMPLICATION: Free software and low cost equipment could be a feasible solution to obtain 3D models for making digital face impressions for maxillofacial prostheses, improving access for clinical centers that do not have high cost technology considered as a prior acquisition.

Coloration of silicone prostheses: technology versus clinical perception. Is there a difference? Part 2, clinical evaluation of a pilot study.

PURPOSE: The aim of this investigation was to explore the relationship between an objective computer measurement of color difference (ΔE) and subjective clinical opinion of a "good" color match between silicone samples and skin. MATERIALS AND METHODS: In Part 1 of this study, silicone samples were colored to match the skin of 19 African-Canadian subjects based on spectrophotometric measurements and pigment formulae determined by computerized color formulation software. Four iterative samples were prepared for each subject; a ΔE value was recorded for each sample to represent the color difference between the silicone sample and skin. In this article, Part 2, five judges independently assessed the color match of the silicone samples to the skin of each of the subjects. Skin and silicone samples were rated on a five-point scale as a measure of "color match." A multivariate analysis was used to determine relationships between judges' assessments and the following variables: color difference between silicone and skin (ΔE), pigment loading, and skin characteristics (L*, a*, b*). RESULTS: There was a positive correlation between judges' scores and low ΔE values for the first two samples. All judges rated the first sample a poorer color match than the fourth sample (p < 0.015). The third sample performed better overall according to judges. Increased pigment loading in the fourth sample resulted in poorer scores. A trend was observed in pigment selection based on skin values, though no significant relationships were determined. CONCLUSION: Spectrophotometry and computerized color formulation technology offer an enhanced understanding of color for its artistic application in facial prosthetic treatment. While some correlation between the objective and subjective assessments of color match exist, it is not a simple relationship. Further study is required to better understand the relationship between technology and clinical perception, specifically in objective and subjective assessments of a "good" color match of silicone to skin.

The rapid prototyping of anatomic models in pulmonary atresia.

OBJECTIVE: The goal of this study was to assess the utility and accuracy of solid anatomic models constructed with rapid prototyping technology for surgical planning in patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. METHODS: In 6 patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries, anatomic models of the pulmonary vasculature were rapid prototyped from computed tomographic angiographic data. The surgeons used the models for preoperative and intraoperative planning. The models' accuracy and utility were assessed with a postoperative questionnaire completed by the surgeons. An independent cardiac radiologist also assessed each model for accuracy of major aortopulmonary collateral artery origin, course, and caliber relative to conventional angiography. RESULTS: Of the major aortopulmonary collateral arteries identified during surgery and conventional angiography, 96% and 93%, respectively, were accurately represented by the models. The surgeons found the models to be very useful in visualizing the vascular anatomy. CONCLUSION: This study presents the novel vascular application of rapid prototyping to pediatric congenital heart disease. Anatomic models are an intuitive means of communicating complex imaging data, such as the pulmonary vascular tree, which can be referenced intraoperatively.