Facial Prostheses Research Articles

Implementation of Cone Beam Computed Tomography, Digital Sculpting and Three-Dimensional Printing in Facial Epithesis—A Technical Note

Prosthetic rehabilitation has hardly changed since the 1970s, and it is a time-consuming process that requires great skill and precision. This article presents the workflow related to the prosthetic reconstruction of patients with extensive maxillofacial defects using digital technologies such as cone beam computed tomography (CBCT), Zbrush software and three-dimensional (3D) printing. The use of CBCT captures a 3D image of a patient’s face in a few seconds, thus shortening the time to prepare an impression and increasing the patient’s comfort. Zbrush digital sculpting software enables one to quickly and efficiently design a prosthetic restoration. Printing a trial version for a try-on, as well as designing and printing pre-cast forms, improves workflow and eliminates the chances of an error. As shown in the example of a patient after a nasal resection, CBCT, digital sculpting, and 3D printing accelerate and improve the workflow of an anaplastologist when designing the epithesis. New technologies reduce costs and save time, while helping to overcome the technical obstacles that limit access to a facial prosthesis.

Effect of Superhydrophobic Coating and Nanofiller Loading on Facial Elastomer Physical Properties.

Facial prosthetics are currently constructed of materials that are far from optimal; superior materials with a “skin-like” feel are required. In this study, the property changes brought about by the consecutive additions of hydrophobic- and uncoated nano-SiO2 to polydimethylsiloxane (PDMS) are assessed, and the alterations are compared with those observed for conventional submicron SiO2-filled materials. In sequence, 0%, 0.5%, 5%, 10%, and 15% by weight of each filler type were successively added to vinyl-terminated PDMS. Tensile, tear, Durometer hardness, translucency, and viscoelastic properties were assessed, and hardness and translucency were further measured after 3000 h of outdoor weathering. The results showed that 15% coated nano- SiO2-filled PDMS materials given the highest tensile strength, elastic modulus, storage modulus, loss modulus, tear strength, and durometer hardness (p < 0.05), whereas 15% submicron coated SiO2-filled materials displayed the highest failure strain and translucency parameter (p < 0.05). Only 10%- and 15%-filled submicron SiO2 PDMS materials were altered by outdoor weathering; nevertheless, the increases were assessed to be too small to be clinically perceptible. As increased filler levels provided protection against solar radiation, heat, and moisture, only unfilled and 0.5%-filled PDMS formulations discolored from weathering. 15%-filled superhydrophobic-coated nano- SiO2-filled PDMS was found to produce the strongest, most tear-resistant, and least translucent materials, but it also produced materials with limited stretchability and high hardness, which were regarded to be downsides for creating a “skin-like” feel.

The Etiology and Management of Dental Implant Failure: A Review.

As the world is embracing technology, dental technology is merging with artificial intelligence. Dentists are striving to perfect the art of placing dental implants. Implants for the rehabilitation and retention of dental and facial prostheses have graduated from a phase of wishful thinking to one of the most gratifying experiences for patients and treating fraternity alike. Implants and restorations supported by implants have a good long-term survival percentage. Complications and implant failure, which can still happen, are seen by many clinicians as significant barriers to implant treatment. Implant therapy still involves a biological healing and integration process despite recent advancements. These biological processes are complex and may be hampered by local or systemic factors, which could result in problems and implant failure. For the implant surgeon and dental professional, it is crucial to manage patients who have certain risk factors and be able to address potential complications and failure. The aim of this article is to discuss frequent complications of implant failure and its management and help clinicians in placing and restoring implants less painfullyand vicariously receive some valuable experience.

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.

AWARENESS, KNOWLEDGE, AND PERCEPTION OF DENTAL IMPLANT AMONG PATIENTS AT A TERTIARY HOSPITAL IN NORTHWESTERN NIGERIA

Background: A dental implant is a prosthesis that interfaces with the jawbone or cranium which is sunk to provide a dental prosthesis such as crown, bridge and denture or provide support for facial prosthesis or act as anchorage to orthodontic appliances. Implants are more retentive, more stable, stronger, functionally effective and provide better quality of life. The aim of this study was to determine the awareness, knowledge and perception of patients attending Dental Department of Federal Medical Centre Gusau, Zamfara State in the clinical applications of dental implant. A ques Methodology: tionnaire-based study was conducted amongst patients attending dental surgery department in Federal Medical Centre Gusau, Zamfara State, Nigeria. A total of 408 participants were recruited through simple random sampling technique. A Self-administered questionnaire was used to collect data which was analyzed using the Statistical Package for Social Sciences (IBM SPSS) software version 21. There were 160 (39.2%) males a Results: nd 248 (60.8%) females with a mean SD of 32.3 11.23 years. Majority (59.8%) of the respondents have not heard about dental implant before, while 164 (40.2%) respondents were aware of the dental implant and majority (n=88) source their information from dentist. Majority (80.5%) selected removable partial denture as alternative option for the replacement of missing teeth. 120 (73.2%) participants know that implant is placed in the jawbone. The perception about the durability of dental implant was good as 152 (92.7%) participants believed that it is durable. 72 (43.9%) participants opted to replace their missing teeth with an implant. The reason for rejecting the implant was due to high cost (43.9%) followed by fear (22%). There is no statistically signicant difference in terms of awareness of dental implant between gender with a p-value of 0.086. However, there is statistically signicant difference when compared with the level of education with a p-value of 0.000. The a Conclusion: wareness, knowledge and perception about dental implant is appreciable. However, cost of treatment is the major hindrance preventing accessibility to implant treatment.

Maxillofacial prosthetic rehabilitation using different retention systems: A review

Maxillofacial abnormalities are the most deleterious to a person's self-esteem and quality of life. Restoration of speech, deglutition, and masticatory functions as well as achieving a normal orofacial appearance are the main objectives of rehabilitation of maxillofacial defects. Any prosthesis can be held in place by anatomical, mechanical, chemical, or surgical anchorage, depending on the clinical scenario. Various methods of retention have evolved over a period of time. Osseointegrated implants have been employed to enhance the retention of facial prosthesis, in the last 20 years. The prosthodontist should be familiar with all the available options, to opt for the appropriate retentive method, while planning for the prosthetic rehabilitation for the patient. In all cases of maxillofacial deformities, optimal outcomes could be a challenging task to accomplish, but careful evaluation, clinical decision-making, and planning can result in prosthesis of acceptable quality that might enhance the patient's quality of life.

Color variations during digital imaging of facial prostheses subjected to unfiltered ambient light and image calibration techniques within dental clinics: An in vitro analysis.

BackgroundThe study aimed to evaluate 1) the amount of color variations presents within clinical images of maxillofacial prosthetic silicone specimens when photographed under different clinically relevant ambient lighting conditions, and 2) whether white balance calibration (WBC) methods were able to mitigate variations in ambient lighting.Methods432 measurements were acquired from standardized images of the pigmented prosthetic silicone specimens within different ambient lighting conditions (i.e., 2 windowed and 2 windowless clinics) at noon with no light modifying apparatus. The specimens were photographed once without any white balance calibration (raw), then independently alongside an 18% neutral gray card and Macbeth color chart for calibration in a post-processing (PPWBC) software, and once after camera calibration (CWBC) using a gray card. The LAB color values were extracted from the images and color variations (ΔE) were calculated after referring to the corresponding spectrophotometric values as control.ResultsImages in windowless and windowed clinics exhibited highly significant differences (p < 0.001) with spectrophotometer (control). CWBC demonstrated no significant differences (p > 0.05) in LAB values across windowed clinics. PPWBC using Macbeth color chart produced no significant differences for a* values (p > 0.05) across all clinics while PPWBC by gray card showed no significant differences (p > 0.05) in LAB values when only similar clinics (either windowed or windowless) were compared.ConclusionSignificant color variations were present for maxillofacial prosthetic specimens owing to natural ambient light. CWBC and PPWBC using color charts were more suitable for color correction across windowed clinics while CWBC and PPWBC using gray cards had better outcomes across windowless setups.

Use of Submental Intubation in the Full-Face Makeover (Orthognathic Surgery, Facial Prosthesis Combined With Rhinoplasty).

Submental intubation is an intubation technique used for the management of airways in patients who suffered from complex maxillofacial trauma. Few studies focused on the role of submental intubation during Full-Face Makeover, like orthognathic surgery, facial prothesis, and rhinoplasty. Authors describe a case series of 5 patients who underwent to Full-Face Makeover with submental intubation to manage the airways. The authors started with the Le Fort I subspinal osteotomy. The maxillary repositioning was guided through a 3D printed intermediate splint in all cases (previously simulated with Dolphin software).Subsequentially, the bilateral sagittal split osteotomy was performed. The mandibular repositioning was guided through a 3D printed final splint. The genioplasty was performed with a horizontal osteotomy after a labial mucosa incision. After the genioplasty, the authors used the incision previously used for the Le Fort I osteotomy to bluntly dissect the tissues in order to insert a custom-made polyether ether ketone zygomatic prosthesis. Lastly, an open rhinoplasty was performed. All the surgery lasted a mean less 6 hours. The submental intubation was removed in the operating room, at the end of the surgery. The patients were then discharged from the hospital 2 days after the surgery in all cases. Submental intubation is a valid method for the airway management in maxillofacial trauma and can be extended in case of Full-Face Makeover like orthognathic surgery combined with rhinoplasty. The absence of nasal traumatism during surgery leads to a more accurate rhinoplasty, with a greater satisfaction for the patient.

Three-Dimentional Printing Materials for Maxillofacial Structure Development: A Review

A 3D printing is an additive manufacturing technique that has wide applications in various fields, including healthcare, especially in producing complex and entangled geometries like maxillofacial structures. Various 3D printing techniques are available; however, the range of biomaterials satisfying the printability criteria is limited. Generally, 3D printing biomaterials fall under classes as such a metals, ceramics, polymers, composites and hydrogels. In maxillofacial structure development, 3D printing is used for manufacturing surgical guides, models, splints, patient-specific implants and facial prostheses. This review describes various 3D printable materials and a brief overview of 3D printing techniques, specifically explored in maxillofacial structure-related applications. 3D bioprinting materials are beyond the scope of this review.

Effect of Nano Titanium Oxide with Different Surface Treatments on Color Stability of Red-Tinted Silicone Rubber.

To improve the color stability of facial prosthesis silicone rubber, this paper studied the effect of nano titanium oxide with different surface treatments on the color stability of red pigment-colored silicone rubber. Under the simulated sunlight aging condition, this paper takes MDX4-4210 silicone rubber as the matrix, silicon aluminum-coated nano TiO2 as the shading agent, and cadmium red oil paint as the colorant, and it observes the values of silicon aluminum-coated nano-TiO2 silicone rubber film with 1 mm thickness and different concentrations (0, 0.05%, 0.10%, and 0.15%) before and after aging. The experimental results showed that in the four concentrations of silicon aluminum-coated nano-TiO2 film, the ΔE, ΔL∗, Δa∗, Δb∗ values gradually decreased with the increase of the concentration of silicon aluminum-coated nano-TiO2. The lowest was in the 0.10% group; however, it increased in the 0.15% group. There was a significant difference among the concentration groups (P < 0.05). The method of covering nano-TiO2 silicone rubber film with different concentrations of silicon aluminum has a certain effect on delaying the discoloration of prosthetic silicone rubber, and it provides a new idea for improving the color stability of the prosthetic silicone rubber.

Stereolithography (STL) measurement rubric for the evaluation of craniomaxillofacial STLs

BackgroundFacial deformities often demand reconstructive surgery and the placement of three-dimensional (3D) printed craniomaxillofacial prostheses. Prostheses manufacturing requires patients’ computed tomography (CT) images. Poor quality images result in incorrectly sized prostheses, necessitating repeat imaging and refitting. The Centre for Rapid Prototyping and Manufacturing (CRPM) produces most facial prostheses in South Africa but does not have a prescribed optimised CT protocol. Therefore, this study was undertaken.MethodsA collection of CRPM STLs used in the design and manufacturing of craniomaxillofacial prostheses is available. The image quality of stereolithography (STL) files of CRPM CT scans was evaluated to determine what constitutes good image quality. This collection was scrutinised for inclusion in the image quality evaluation. After scrutiny, 35 STLs of individuals ≥15 years of age were selected and included metadata attached to the DICOM file. Furthermore, only STLs created without manipulation by the same designer were included in the collection. Before the qualitative evaluation of the STLs, eight different critical anatomical reference points (CARPs) were identified with the assistance of an expert team. A visual acuity rating scale of three categories was devised for each CARP, where 1 was allocated to poor visual acuity, 2 to partial, and 3 to good visual acuity. Similarly, rating scales were devised for the presence of concentric rings and the overall impression score awarded by the two designers involved in the design and manufacturing of the prostheses. This stereolithography measurement rubric (SMR) was then applied to the 35 STLs by a team of three experts, including the two designers, during a structured evaluation session. The scores were used to calculate summary and inferential statistics.ResultsScores grouped around the central rating of partial visual acuity. The three evaluators’ mean total CARP scores ranged from 13.1 to 14.4 (maximum possible score 24), while the mean total CARP + ring scores ranged from 15.8 to 17.1 (maximum possible score 27). No significant differences were detected between the evaluators’ scores.ConclusionThis SMR appears to be the first of its kind. This image quality assessment of STLs provides the groundwork for finer CT image quality evaluation to formulate a CT imaging protocol for the CRPM to design and manufacture accurate internal cranial prostheses.

Épithèse faciale par CFAO : aspects cliniques et techniques

The face is an important part of the human body from an anatomical, functional, aesthetic and psychosocial point of view.It can be the site of several mutilations resulting from trauma, treatment of neoplasms and congenital malformations.The plastic facial prosthesis is therefore indicated to restore these facial deformities and to compensate for the various consequences. Recently, digital technologies have shown an increasing impact on the future of maxillofacial rehabilitation. Computer-aided design and manufacturing technique enabled practitioners to acquire numerical data, perform three-dimensional reconstructions, and then materialize and manufacture the facial epithesis through various manufacturing processes, by addition or subtraction. The aim of this article is to describe, through a clinical case, the steps of realization of a nasal epithesis by CAD/CAM, in a patient who underwent a surgical exeresis of the nasal pyramid following a squamous cell carcinoma. Thus, the clinical and technical aspects are highlighted, as follows, the taking of the impression, the materials used, the set-up and the make-up, as well as the software and the useful concepts for the computer-assisted realization of a facial plastic prosthesis of the nasal epithesis type. Our therapy will also focus on the interest of the multidisciplinary approach in Maxillofacial Prosthodontics.

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.

Facial prosthesis fabricated from dental material for an exposed reconstruction plate: A clinical report

Facial prostheses are often fabricated for cosmetic and psychological reasons for patients with facial defects after tumor resection. Each case is unique, and fabricating a facial prosthesis that is tailored to the individual patient requires use of specific materials and a degree of flexibility. This article describes a facial prosthesis that was made using an Adams clasp and acrylic resin for an elderly patient with metal exposure after mandibulectomy.

Development of a customised 3D printer as a potential tool for direct printing of patient-specific facial prosthesis

This study demonstrates a cost-effective portable fabrication system for 3D printing complex structures from polydimethylsiloxane (PDMS). Material development and characterisation allowed for the design and production of a 3D printer that is capable of fabricating PDMS structures using a photo-initiator and a LED curing process. A 3D model of a participant’s ear was captured using a handheld scanner. These data were used to directly 3D print an ear. Micro-extrusion direct deposition of PDMS at room temperature is demonstrated via a custom designed 3D printer, with in situ UV cross-linking to facilitate curing of the PDMS during the 3D printing process. This 3D printer has great potential to be used as a fast and facile fabrication approach to create facial and other prosthesis. Future developments will also focus on other application areas such as microfluidics, flexible electronics, and other biomedical applications.

Prosthetic management of a midfacial defect

Surgical ablation of a large tumor creates a defect which is technically difficult to reconstruct. Radiated tissue bed poses a challenge to reconstruction and is complicated in presence of osteoradionecrosis. This report describes a case of a 62 year old gentleman with oral cancer who underwent surgery and radiotherapy twice. He developed an orocutaneous defect (OCD) following surgery and radiotherapy. Prosthetic rehabilitation of OCD was done. Full facial impression with irreversible hydrocolloid was made and wax sculpture made on the model obtained. Standard laboratory steps were followed for mould fabrication and maxillofacial silicone was used to fabricate the prosthesis. It was retained to the spectacle with silicone adhesives. The silicone facial prosthesis provided to the patient was easy to use, covered the defect and improved the quality of life of the patient.

Trueness and precision of skin surface reproduction in digital workflows for facial prosthesis fabrication

Statement of problemHow much skin surface details of facial prostheses can be transferred throughout the digital production chain has not been quantified. PurposeThe purpose of this in vitro study was to quantify the amount of skin surface details transferred from the prosthesis virtual design through the prototype printing with various additive manufacturing (AM) methods to the definitive silicone prosthesis with an indirect mold-making approach. Material and methodsTwelve test blocks with embossed wrinkles of 0.05 to 0.8 mm and 12 test blocks with applied earlobe skin structures were printed with stereolithography (SLA), direct light processing (DLP), and PolyJet methods (n=4). DLP and SLA prototype specimens were duplicated in wax. All specimens were then transferred into medical-grade silicone. Rz values of the wrinkle test blocks and the root mean square error (RMSE) of the earlobe test blocks were evaluated by laser topography to determine the trueness and precision of each stage. ResultsFor the earlobe test blocks, the PolyJet method had superior trueness and precision of the final skin surface reproduction. The SLA method showed the poorest trueness, and the DLP method, the lowest precision. For the wrinkle test blocks, the PolyJet method had the best wrinkle profile reproduction level, followed by DLP and SLA. ConclusionsThe indirect mold-making approach of facial prostheses manufacturing may be associated with 7% of skin surface profile loss with SLA, up to 20% with DLP, and no detail loss with PolyJet.

The rising challenge of mucormycosis for maxillofacial prosthodontists in the Covid-19 pandemic: A literature review.

This review examines the importance of prosthetic rehabilitation after surgical treatment of mucormycosis in the context of expected increases in cases during the current COVID-19 pandemic. Google Scholar, Web of Science, Scopus, and PubMed databases were searched for relevant articles published between 2010 and 2021. Articles that provided a full description of prosthetic treatment after surgical treatment of mucormycosis were included in the review. Out of 30 articles describing orofacial prosthetic rehabilitation after surgical treatment of mucormycosis published during the 12-year target period, 19 reported patients with diabetes, two described mucormycosis as a post-COVID-19 complication, and 25 were reports from India. Most of the prosthetic treatments used a definitive obturator (63.3%) either alone or in combination with other forms of prosthetic rehabilitation. Other prosthetic strategies included an orbital prosthesis (26.6%), a facial prosthesis with or without a nasal replacement (16.6%), a surgical or interim obturator, a conventional complete denture, and a cast partial denture. Six articles (20%) mentioned the use of combined prosthetic rehabilitation involving multiple regions of the face and oral cavity. Prosthetic rehabilitation after surgical treatment of mucormycosis is essential for the early restoration of oral function and facial esthetics. Given the aggressive nature of mucormycosis and the increasing number of cases reported during the COVID-19 pandemic, prosthodontists need to share their experiences with prosthetic rehabilitation of the defects that result from this disease to improve patients' quality of life.

Bonding strength of 3D printed silicone and titanium retention magnets for maxillofacial prosthetics application.

To assess the bonding between conventional and additively manufactured silicone elastomers and cylindrical retention titanium magnets for anchorage of facial prostheses. The customized titanium retention magnets were embedded in conventional and additively produced silicone blocks without primer application (n = 20) and with two commercially available primers G611 (n = 20) and A304 (n = 20) applied onto the magnet surface. The pull out test was performed in the universal testing machine using 45° and 90° angulation and the pull out strength was measured for each group. Additionally the SEM images of the pulled out magnets' surface were obtained and the amount of residual silicone onto the magnet surface was quantified. Significantly higher pull out strength values (p < 0.05) were revealed for 90° specimens (0.11 - 0.17 ± 0.01 N/mm2) compared to the 45° group (0.03 ± 0.02 N/mm2). The pull out test with primer revealed no significant differences between the G 611 and A 304 primers in the additive group. However, significantly (p < 0,05) higher values were observed for conventional specimens in the A304 group (1.10 ± 0.21 N/mm2) compared to the G611 group (0.59 ± 0.27 N/mm2). The application of both used primers may be an acceptable technical option for the anchorage of retention titanium magnets in silicone facial prostheses, produced additively in a fully digital workflow.

AN OVERVIEW OF EXTRAORAL MAXILLOFACIAL PROSTHESIS MATERIALS

Unaesthetic maxillofacial defects decreases social acceptance. Prosthetic rehabilitation of facial defects makes the life easier with improved esthetics. Prosthetic restoration of such defects is an ancient art, in which success has always being limited by unavailability of adequate materials. The success of any facial prosthesis depends on the physical and mechanical properties of the material. The rehabilitation of patients requiring not only the replacement of missing body part but also a loss of psychological confidence is a challenging task. Since maxillofacial defects lie on the face, the materials used for fabricating the prosthesis should fulfill a variety of requirements. At present, there is no ideal material which can be universally used. The scope of this article is in providing some background about the evolution and current trends in using these materials.