Quality of life assessment of patients utilizing orbital implant-supported prostheses

Effect of spatial arrangement and clinical service lifetime simulation on the retention of magnetic units used in implant-anchored orbital prostheses

STATEMENT OF PROBLEM

Evidence for the optimal spatial arrangement of magnetic attachments in implant-supported orbital prostheses is lacking.

PURPOSE

The purpose of this in vitro study was to assess the effect of 6 different spatial arrangements on the retentive force of magnetic attachments following the in vitro simulation of clinical service by insertion-removal test cycles and the contribution of artificial aging to the morphological alterations induced on the magnetic surfaces.

MATERIAL AND METHODS

Ni-Cu-Ni plated disk-shaped neodymium (Nd) magnetic units (d=5 mm, h=1.6 mm) were secured on leveled (50×50×5 mm, n=3) and angled (40×45×40 mm, interior angle=90 degrees, n=3) pairs of test panels in 6 different spatial arrangements: triangular_leveled (TL), triangular_angled (TA), square_leveled (SL), square_angled (SA), circular_leveled (CL), and circular_angled (CA) generating corresponding test assemblies (N=6). TL and TA arrangements included 3 magnetic units (3-magnet groups) and SL, SA, CL, and CA 4 (4-magnet groups). The retentive force (N) was measured at a mean crosshead speed of 10 mm/min (n=10). Each test assembly was subjected to insertion-removal test cycles with a 9-mm amplitude, ν=0.1 Hz, and n=10 consequent retentive force measurements at a crosshead speed of 10 mm/min at 540, 1080, 1620, and 2160 test cycles. Surface roughness alterations following the 2160 test cycles were measured by calculating the Sa, Sz, Sq, Sdr, Sc, and Sv parameters with an optical interferometric profiler with 5 new magnetic units used as a control group. Data were analyzed with 1-way ANOVA and Tukey HSD post hoc tests (α=.05).

RESULTS

The 4-magnet groups had statistically significantly higher retentive force than the 3-magnet ones at baseline and following the 2160 test cycles (P<.05). In the 4-magnet group, the ranking at baseline was SA<CA<CL<SL (P<.05) and following the test cycles SA=CA<CL<SL (P<.05). No statistically significant differences were found in the surface roughness parameters (Sa, Sz, Sq, Sdr, Sc, and Sv) following the 2160 test cycles among the experimental groups tested (P>.05).

CONCLUSIONS

Four magnetic attachments placed on an SL spatial arrangement resulted in the highest retention force but presented with the highest force reduction following the in vitro simulation of clinical service by insertion-removal test cycles.

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.

Patient satisfaction with different types of craniofacial prostheses

STATEMENT OF PROBLEM

A maxillofacial prosthesis represents an effective method of giving maxillofacial defects a positive esthetic appearance with minimal risk. However, studies of complications among prosthesis wearers are lacking.

PURPOSE

The purpose of this cross-sectional study was to determine levels of patient satisfaction with various maxillofacial prostheses and retention types, as measured through a survey questionnaire package.

MATERIAL AND METHODS

Patients treated at the Sunnybrook Health Sciences Center Craniofacial Prosthetics Unit (CPU) since 2015 were included. They had been treated according to a standardized protocol and answered a survey questionnaire package with the following sections: demographics, frequency of prosthesis usage, and the Toronto Outcome Measure for Craniofacial Prosthetics (TOMCP-27) survey addressing patient satisfaction. To be eligible for this study, patients must have been more than 18 years of age, in possession of a maxillofacial prosthesis, and received treatment at the Sunnybrook Health Sciences Center CPU since 2015.

RESULTS

A total of 157 patients were eligible and contacted, of whom 51 agreed to participate in the survey. The study population was overall extremely satisfied with their maxillofacial prostheses. In 77.8% of the TOMCP-27 questions, the largest group of patients chose the answer demonstrating the highest level of satisfaction. Of all prosthesis types surveyed, patients with auricular prostheses reported the greatest rates of satisfaction, with the entire group having selected answers corresponding to the highest levels of overall satisfaction. However, patients with orbital prostheses were more likely to experience varying degrees of dissatisfaction, with 72% of the highest reported levels of dissatisfaction being from this prosthesis group. In addition, patients with osseointegrated implant-retained prostheses reported higher satisfaction levels with other retention methods, with the bar clasp group outperforming the magnetic coupling retention group.

CONCLUSIONS

Patients experienced an excellent overall rate of satisfaction with their maxillofacial prostheses. Future development should focus on the continued development of osseointegrated methods, improved magnetic coupling, and improved prosthesis technology, especially for orbital prostheses.

PVGAN: A generative adversarial network for object simplification in prosthetic vision

OBJECTIVE

By means of electrical stimulation of the visual system, visual prostheses provide promising solution for blind patients through partial restoration of their vision. Despite the great success achieved so far in this field, the limited resolution of the perceived vision using these devices hinders the ability of visual prostheses users to correctly recognize viewed objects. Accordingly, we propose a deep learning approach based on Generative Adversarial Networks (GANs), termed PVGAN, to enhance object recognition for the implanted patients by representing objects in the field of view based on a corresponding simplified clip art version.

APPROACH

To assess the performance, an axon map model was used to simulate prosthetic vision in experiments involving normally-sighted participants. In these experiments, four types of image representation were examined. The first and second types comprised presenting phosphene simulation of real images containing the actual high-resolution object, and presenting phosphene simulation of the real image followed by the clip art image, respectively. The other two types were utilized to evaluate the performance in the case of electrode dropout, where the third type comprised presenting phosphene simulation of only clip art images without electrode dropout, while the fourth type involved clip art images with electrode dropout.

MAIN RESULTS

The performance was measured through three evaluation metrics which are the accuracy of the participants in recognizing the objects, the time taken by the participants to correctly recognize the object, and the confidence level of the participants in the recognition process. Results demonstrate that representing the objects using clip art images generated by the PVGAN model results in a significant enhancement in the speed and confidence of the subjects in recognizing the objects.

SIGNIFICANCE

These results demonstrate the utility of using GANs in enhancing the quality of images perceived using prosthetic vision.

Outcome measures in facial prosthesis research: A systematic review

STATEMENT OF PROBLEM

Facial prosthesis research uses a wide variety of outcome measures, which results in challenges when comparing the effectiveness of interventions among studies. Consensus is lacking regarding the most appropriate and meaningful outcome measures to use in facial prosthesis research to capture important perspectives.

PURPOSE

The purpose of the systematic review was to identify and synthesize outcome measures used in facial prosthesis research.

MATERIAL AND METHODS

Electronic searches were performed in 11 databases (including nonpeer-reviewed literature). The citations were searched, and expert societies were contacted to identify additional studies. Inclusion criteria comprised studies of participants with facial defects who required or had received prosthetic rehabilitation with an external facial prosthesis. Exclusion criteria comprised participants with ocular prostheses, case reports, case series with fewer than 5 participants, laboratory-based studies, and studies published before 1980. Study selection was performed independently by 2 reviewers. Discrepancies were resolved through discussion or by a third reviewer. Outcome measures were synthesized with a categorization approach based on the perspective, theme, and subtheme of the outcome measures. Quality assessment was performed with an appraisal tool that enabled evaluation of studies with diverse designs.

RESULTS

Database searching identified 13 058 records, and 7406 remained after duplications were removed. After initial screening, 189 potentially relevant records remained, and 186 full texts were located (98% retrieval rate). After full-text screening, 124 records were excluded. Citation searches and contact with expert societies identified 4 further records. In total, 69 articles (grouped into 65 studies) were included. Studies were categorized as per the perspective of their outcome measures, with the following findings: patient-reported (74% of studies), clinical indicators (34%), clinician-reported (8%), multiple viewpoints (6%), and independent observer-reported (3%). Patient-reported outcome measures included tools to assess satisfaction, quality of life, and psychologic health. Variability in the choice of outcome measures was evident among the studies, with many self-designed, unvalidated, condition-specific questionnaires reported. A greater number of outcome measure themes emerged over time; themes such as service delivery and health state utility have recently been evaluated.

CONCLUSIONS

Over the past 40 years, facial prosthesis research has focused on patient-reported outcome measures. Outcome measures relating to other perspectives have been used less frequently, although new themes appear to be emerging in the literature. Future research should use outcome measures with appropriate measurement properties for use with facial prosthetics.

Systematic Review of Clinical Applications of CAD/CAM Technology for Craniofacial Implants Placement and Manufacturing of Orbital Prostheses

This systematic review was aimed at gathering technical and clinical applications of CAD/CAM technology for the preoperative planning of craniofacial implants placement, designing of molds and substructures and fabrication of orbital prostheses. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, an electronic search was executed. Human studies that utilized digital planning systems for the prosthetic rehabilitation of orbital defects were included. A total of 16 studies of 30 clinical cases, which were virtually planned through various digital planning and designing software, were included. The most common preoperative data required for digital planning were CT scans in 15 cases, the 3DSS-STD-II scanning system in 5 cases, an Artec Color 3D scanner in 3 cases and a NextEngine Desktop 3D laser scanner in 2 cases. Meanwhile, the digital designing software were Ease Orbital Implant Planning EOIPlan software in eight cases, Geomagic software in eight cases, Simplant software in four cases and Artec Studio 12 Professional in three cases. Surgical templates were fabricated for 12 cases to place 41 craniofacial implants in the orbital defect area. An image-guided surgical navigation system was utilized for the placement of five orbital implants in two cases. Digital designing and printing systems were reported for the preoperative planning of craniofacial implants placement, designing of molds and substructures and fabrication of orbital prostheses. The studies concluded that the digital planning, designing and fabrication of orbital prostheses reduce the clinical and laboratory times, reduces patient visits and provide a satisfactory outcome; however, technical skills and equipment costs are posing limitations on the use of these digital systems.

Osseointegrated Implants for Orbito-Facial Prostheses: Common Complications and Solutions

PURPOSE

To evaluate anatomical and functional results of osseointegration with magnetic coupling for oculofacial prosthetic rehabilitation after exenteration.

METHODS

This retrospective study included 11 consecutive patients who received orbital reconstruction and oculofacial prosthetic rehabilitation between September 2015 and October 2019. Patient demographics, surgical indications, previous treatment procedures, histopathologic features, and reconstructive procedures were recorded.

RESULTS

The mean age was 37.81 ± 23 years (range 5-78 years). The mean follow-up was 23.81 ± 12 months (range 10-48 months). The principal diagnoses were squamous cell carcinoma of the eyelids (n = 2/11), mucoepidermoid carcinoma of the maxillary sinus (n = 2/11), rhabdomyosarcoma (n = 1/11), mucormycosis (n = 1/11), neurofibromatosis (n = 1/11), basosquamous carcinoma (n = 1/11), malign melanoma (n = 1/11), primitive neuroectodermal tumor (n = 1/11), and retinoblastoma (n = 1/11). Six of the patients were repaired by primary closure. Procedures performed to reconstruct the orbital cavity included split-thickness skin graft (n = 2/11), temporalis muscle flap (n = 2/11), and frontalis muscle flap (n = 1/11). Nine of the 11 patients who received orbital implants were successfully rehabilitated by epithesis. Postoperative complications included implant loss (n = 4/11), periprosthetic local infection (n = 3/11), and soft tissue overgrowth around the orbital prosthesis (n = 2/11). All patients had Straumann bone level implant (Basel, Switzerland) osseointegrated titanium implants (3.5 mm) placed in a 2-stage procedure over a span of 3 to 4 months with subsequent successful prosthesis fitting.

CONCLUSION

The reconstructive methods following orbital exenteration, should be customized according to the patients' characteristics such as extension of the orbital defect, bone quality, and expectations to achieve satisfactory results.

A Digital Method to Fabricate the Ocular Portion of An Orbital Prosthesis with A Smartphone Camera, Color Calibration and Digital Printing

Conventional techniques described in the literature for the manufacture of ocular prostheses are time-consuming since they involve manual work. The use of technologies could improve this laborious process, providing better esthetic outcomes. This technique describes how to manufacture the ocular portion of an orbital prosthesis using a smartphone camera, color calibration with a tooth shade guide, and digital printing. This method allows clinicians to fabricate customized ocular prosthesis by using a photograph of the patient's eye, thus eliminating the need for hand-painting and manual work, and reducing fabrication time.

Late reconstruction of extensive orbital floor fracture with a patient-specific implant in a bombing victim

Fractures of the orbital floor and walls are among the most frequent maxillofacial fractures. Virtual three-dimensional (3D) planning and use of patient-specific implants (PSIs) could improve anatomic and functional outcomes in orbital reconstruction surgery. The presented case was a victim of a terrorist attack involving improvised explosive devices. This 58-year-old female suffered severe wounds caused by a single piece of metal from a bomb, shattering the left orbital floor and lateral orbital wall. Due to remaining hypotropia of the left eye compared to the right eye, late orbital floor reconstruction was carried out with a personalised 3D printed titanium implant. We concluded that this technique with PSI appears to be a viable method to correct complex orbital floor defects. Our research group noted good aesthetic and functional results one year after surgery. Due to the complexity of the surgery for a major bony defect of the orbital floor, it is important that the surgery be executed by experienced surgeons in the field of maxillofacial traumatology.