Restoration of the donor face after facial allotransplantation: digital manufacturing techniques

The future of maxillofacial prosthodontics in North America: The role of advanced digital technology and artificial intelligence - A discussion document

STATEMENT OF PROBLEM

Maxillofacial prosthodontists were advanced digital technology (ADT) adopters early in the new Millennium. The past two decades saw a range of digital enablers emerge including digital imaging (internal and surface), digital surgical planning, digital functional assessment, subtractive and additive manufacturing, navigation, and robotics among others. Artificial Intelligence (AI) is the latest ADT arrival that will be a challenging disruptive technology. ADT has served as a profound change agent in maxillofacial prosthodontics. The intent was to explore the process and level of ADT engagement in maxillofacial prosthodontics.

PURPOSE

The purpose was twofold. Firstly, to explore maxillofacial prosthodontic engagement of ADT. Secondly, to develop a discussion document to assist the American Academy of Maxillofacial Prosthetics (AAMP) with establishing a collective awareness and considered opinion on the future of maxillofacial prosthodontics in the digital era.

MATERIAL AND METHODS

AAMP member interest in ADT was assessed through analysis of AAMP annual congress programs and publications in the Journal of Prosthetic Dentistry (JPD). The history of the maxillofacial prosthodontic journey to the digital era was undertaken with a selective literature review. The perceptions maxillofacial prosthodontists hold on ADT engagement was assessed through a survey of AAMP members. Developing an understanding of the influence AI was conducted with a review of pertinent literature.

RESULTS

From 2011-2020, an annual mean of 38% of papers published in the JPD involved clinical use of ADT. From 2017-2019, 44% of invited presentations at AAMP annual congresses included clinical use of ADT. The journey to the digital era distinguished three periods with formative and consolidation periods influencing the innovation digital era. The AAMP member survey had a 59% response rate and studied 10 domains through 31 questions. Of the respondents, 89% thought ADT important to the future of maxillofacial prosthodontics.

CONCLUSIONS

The discussion document will assist the AAMP in developing a collective consciousness and considered opinion on ADT in the future of maxillofacial prosthodontics. Members of the AAMP have a developed interest in clinical applications of ADT. A great challenge is that no formal education, training, or clinical competency requirements for ADT could be identified. Clinical competency requirements are important to prepare maxillofacial prosthodontics for the inevitability of a digital era future. The discussion document poses the fundamental question of whether maxillofacial prosthodontists will remain as passive end users of ADT and AI or will they become engaged knowledge workers that have determined clinical competency in ADT and AI in patient care. Without this knowledge worker role, maxillofacial prosthodontists may experience difficulty being part of the inevitable ADT-AI driven future.

Facial Allograft Donation: An Interpretative Phenomenological Analysis of the Experiences of Family Members

Facial allograft transplantation can be regarded as a particular and complex type of donation because of its perceptibility and the importance of the face as an identity characteristic. As research on this topic is currently lacking, the objective of this study is to explore the experiences of the family members of the donor in facial allograft donation. In-depth, semi-structured interviews were conducted separately with the donor's family members and analyzed using interpretative phenomenological analysis. Six themes were identified: (1) Contrasting facial donation to that of more commonly donated organs; (2) Consenting to facial donation; (3) Expectations towards the recipient of the facial graft; (4) Expectations and consequences of restoration of the donor's face; (5) Relationship with the medical team during the process; and (6) Media attention. The findings of our study help to better support donor families through the facial donation process and to improve facial transplantation procedures.

The future of maxillofacial prosthodontics in North America: Part II - A survey

STATEMENT OF PROBLEM

Head and neck care has been transformed by the introduction of advanced digital technologies that will continue to be important change drivers for maxillofacial prosthodontics. Insight into these changes is important in answering the question of whether maxillofacial prosthodontics is appropriately prepared to contribute effectively to future multidisciplinary care of the head and neck.

PURPOSE

The purpose of this survey was to gain insight into the perception of changes experienced by maxillofacial prosthodontists in relation to clinical practice. The findings of this survey may assist the future development of the subspecialty.

MATERIAL AND METHODS

An exploratory cross-sectional survey was conducted by using a convenience sample of members of the American Academy of Maxillofacial Prosthetics. The survey considered 10 domains and 31 questions. Fully completed surveys (164) provided a 59% response. Descriptive statistics used percentage responses to reduce and characterize perceptions across respondents.

RESULTS

Eighty-four percent of the respondents were from the United States. Results should be interpreted based on this cohort. Respondents reported a change in care delivered over the past 10 years (72%), with the most important causes of change attributed to surgery (60%) and advanced digital technologies (56%). Respondents perceived advanced digital technologies as being central to the future of maxillofacial prosthodontics (89%) and important in attracting younger colleagues (88%). Sixty-three percent believed training programs were not providing adequate education and training in the use of advanced digital technology.

CONCLUSIONS

The perception of maxillofacial prosthodontists regarding changes taking place in care delivery was that the most important changes in the past 10 years were attributed to surgery and advanced digital technologies, that persisting pressures related to few institutional positions, that the subspecialty was poorly visible, that remuneration for care was inadequate and referring disciplines did not understand the subspecialty, that advanced digital technologies were considered central to the future of maxillofacial prosthodontics and important to attract younger colleagues to the subspecialty, that barriers to advanced digital technology use included funding for equipment acquisition, institutional funding support, and remuneration for their use in care delivery, and that maxillofacial prosthodontic programs were not providing adequate education and training in advanced digital technologies.

The future of maxillofacial prosthodontics in North America: Part I-Journey to the present

STATEMENT OF PROBLEM

Understanding how maxillofacial prosthodontists are perceiving changes in head and neck care and the impact of advanced digital technologies on maxillofacial prosthodontics is important. However, no studies could be identified that specifically addressed these subjects.

PURPOSE

The purpose of this review of selected literature was to identify issues that guided the development of maxillofacial prosthodontics and the concerns that persist. The review also considered contemporary influences that will affect the future of maxillofacial prosthodontics. The conclusions of the review were used to interpret the results of the exploratory survey reported in Part II.

MATERIAL AND METHODS

The review of selected literature was related to the development of maxillofacial prosthodontics in North America between 1950 and 2018. Literature that was considered relevant to the purpose of the review was included.

RESULTS

The review yielded 37 references of interest: 34 peer-reviewed publications, 1 guideline, 1 historical publication, and 1 website. Periods in the development of maxillofacial prosthodontics in North America were identified as formation, consolidation, and innovation.

CONCLUSIONS

It was concluded that concerns in subspecialty programs and clinical practice had origins in the formation and consolidation periods. These persisting concerns extended into the innovation period. Contemporary influences in head and neck surgery will continue to affect the future of maxillofacial prosthodontics. Advanced digital technologies appeared to be central to driving change. Understanding the evolution of maxillofacial prosthodontics was an important first step in providing context when interpreting the results of a survey of maxillofacial prosthodontists reported as Part II of this work.

Facial Transplantation for an Irreparable Central and Lower Face Injury: A Modernized Approach to a Classic Challenge

BACKGROUND

Facial transplantation introduced a paradigm shift in the reconstruction of extensive facial defects. Although the feasibility of the procedure is well established, new challenges face the field in its second decade.

METHODS

The authors' team has successfully treated patients with extensive thermal and ballistic facial injuries with allotransplantation. The authors further validate facial transplantation as a reconstructive solution for irreparable facial injuries. Following informed consent and institutional review board approval, a partial face and double jaw transplantation was performed in a 25-year-old man who sustained ballistic facial trauma. Extensive team preparations, thorough patient evaluation, preoperative diagnostic imaging, three-dimensional printing technology, intraoperative surgical navigation, and the use of dual induction immunosuppression contributed to the success of the procedure.

RESULTS

The procedure was performed on January 5 and 6, 2018, and lasted nearly 25 hours. The patient underwent hyoid and genioglossus advancement for floor-of-mouth dehiscence, and palate wound dehiscence repair on postoperative day 11. Open reduction and internal fixation of left mandibular nonunion were performed on postoperative day 108. Nearly 1 year postoperatively, the patient demonstrates excellent aesthetic outcomes, intelligible speech, and is tolerating an oral diet. He remains free from acute rejection.

CONCLUSIONS

The authors validate facial transplantation as the modern answer to the classic reconstructive challenge imposed by extensive facial defects resulting from ballistic injury. Relying on a multidisciplinary collaborative approach, coupled with innovative emerging technologies and immunosuppression protocols, can overcome significant challenges in facial transplantation and reinforce its position as the highest rung on the reconstructive ladder.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Dental considerations and the role of prosthodontics and maxillofacial prosthetics in facial transplantation

BACKGROUND

Facial transplantation (FT) is a challenging reconstructive endeavor that requires the expertise of a multidisciplinary team. The specific role of maxillofacial prosthodontists has not yet been reported in detail.

METHODS

This review considers the contributions of prosthodontists throughout the FT process, from patient selection and dental evaluation to long-term dental rehabilitation of the transplant patient postoperatively. Moreover, considerations of dental management are evaluated.

RESULTS

In the almost 40 FT reported in the literature, the most consistently documented contribution by prosthodontists is the fabrication of a donor mask to maintain donor integrity. Though infrequently reported, prosthodontists have the potential to plan and perform a variety of dental procedures and follow-up plans.

CONCLUSIONS

When applicable, facial transplant teams are tasked with providing optimal stomatognathic function and dental occlusion to recipients with severe facial disfigurement. The maxillofacial prosthodontist's contribution is crucial to the long-term dental restoration of the edentulous facial transplant candidate, in addition to the fabrication of the donor mask which fulfills the team's ethical responsibilities.

PRACTICAL IMPLICATIONS

Maxillofacial prosthodontists play a pivotal role in facial transplantation, particularly when jaw segments are intended for transplantation.

Facial Donor Restoration: One-Step Technique

PURPOSE

Successful management of facial allotransplantation requires planning and overcoming a long list of obstacles, not least, the restoration of the donor cadaver (DC).

MATERIALS AND METHODS

We have presented an innovative single-step facial reconstruction technique for the DC using light-curing material to simplify the infrastructure needs and optimize the time and costs associated with traditional facial restoration techniques reported to date. We also developed a study based on the creation of 7 facial masks over a white male formaldehyde-preserved cadaver head to evaluate the production time of the mask, likeness to the original face, temperature, and adaptation of the mask to the defect.

RESULTS

The average time for the adjustment of the light-curing resin sheets over the DC, photopolymerization, and cosmetic adjustment and application over the facial defect was 5, 4, and 16.4 minutes, respectively, for a global average time of 25.4 minutes. In all cases, the likeness to the original was good, and the average temperature over the donor area was 19.8°C. The adaptation of the mask to the facial defect was accurate in all cases.

CONCLUSIONS

The presented one-step technique proposed for facial restoration of the DC had a short learning curve, low costs, and accurate and predictable results.

Development and refinement of computer-assisted planning and execution system for use in face-jaw-teeth transplantation to improve skeletal and dento-occlusal outcomes

PURPOSE OF REVIEW

To describe the development and refinement of the computer-assisted planning and execution (CAPE) system for use in face-jaw-teeth transplants (FJTTs).

RECENT FINDINGS

Although successful, some maxillofacial transplants result in suboptimal hybrid occlusion and may require subsequent surgical orthognathic revisions. Unfortunately, the use of traditional dental casts and splints pose several compromising shortcomings in the context of FJTT and hybrid occlusion. Computer-assisted surgery may overcome these challenges. Therefore, the use of computer-assisted orthognathic techniques and functional planning may prevent the need for such revisions and improve facial-skeletal outcomes.

SUMMARY

A comprehensive CAPE system for use in FJTT was developed through a multicenter collaboration and refined using plastic models, live miniature swine surgery, and human cadaver models. The system marries preoperative surgical planning and intraoperative execution by allowing on-table navigation of the donor fragment relative to recipient cranium, and real-time reporting of patient's cephalometric measurements relative to a desired dental-skeletal outcome. FJTTs using live-animal and cadaveric models demonstrate the CAPE system to be accurate in navigation and beneficial in improving hybrid occlusion and other craniofacial outcomes. Future refinement of the CAPE system includes integration of more commonly performed orthognathic/maxillofacial procedures.

Perioperative Nursing Management of Donor and Recipient Patients Undergoing Face Transplantation

Individuals with debilitating facial injuries and deformities have achieved significant improvement of aesthetic form and function after undergoing a face transplantation. The involvement of surgical technologists and perioperative nurses in the care of the recipient and donor plays a critical role in the success of these procedures. There are unique challenges that staff members may be presented with when caring for a donor and recipient undergoing a face transplantation, including less comfort with and knowledge of the surgical procedure and instrumentation, an increased amount of equipment and personnel in the OR, donor and recipient admission and discharge care, and increased shift length. At New York University Langone Medical Center, New York, we have developed a comprehensive process to prepare staff members to care for patients undergoing face transplantation.

Three-dimensional printing for restoration of the donor face: A new digital technique tested and used in the first facial allotransplantation patient in Finland

BACKGROUND AND AIMS

Prosthetic mask restoration of the donor face is essential in current facial transplant protocols. The aim was to develop a new three-dimensional (3D) printing (additive manufacturing; AM) process for the production of a donor face mask that fulfilled the requirements for facial restoration after facial harvest.

MATERIALS AND METHODS

A digital image of a single test person's face was obtained in a standardized setting and subjected to three different image processing techniques. These data were used for the 3D modeling and printing of a donor face mask. The process was also tested in a cadaver setting and ultimately used clinically in a donor patient after facial allograft harvest.

RESULTS

and Conclusions: All the three developed and tested techniques enabled the 3D printing of a custom-made face mask in a timely manner that is almost an exact replica of the donor patient's face. This technique was successfully used in a facial allotransplantation donor patient.

Medical 3D Printing for the Radiologist

While use of advanced visualization in radiology is instrumental in diagnosis and communication with referring clinicians, there is an unmet need to render Digital Imaging and Communications in Medicine (DICOM) images as three-dimensional (3D) printed models capable of providing both tactile feedback and tangible depth information about anatomic and pathologic states. Three-dimensional printed models, already entrenched in the nonmedical sciences, are rapidly being embraced in medicine as well as in the lay community. Incorporating 3D printing from images generated and interpreted by radiologists presents particular challenges, including training, materials and equipment, and guidelines. The overall costs of a 3D printing laboratory must be balanced by the clinical benefits. It is expected that the number of 3D-printed models generated from DICOM images for planning interventions and fabricating implants will grow exponentially. Radiologists should at a minimum be familiar with 3D printing as it relates to their field, including types of 3D printing technologies and materials used to create 3D-printed anatomic models, published applications of models to date, and clinical benefits in radiology. Online supplemental material is available for this article.

Digital capture, design, and manufacturing of a facial prosthesis: Clinical report on a pediatric patient

A digitally captured, designed, and fabricated facial prosthesis is presented as an alternative to customary maxillofacial prosthodontics fabrication techniques, where a facial moulage and patient cooperation may be difficult.