Facial prosthesis

Abstract: Statement of problem Facial defects secondary to the treatment of neoplasms, congenital malformations, and trauma result in multiple functional and psychosocial difficulties. Prosthetic rehabilitation attempts to restore these facial disfigurements and may improve the level of function and self-esteem for these patients. However, a limited number of studies have evaluated the change in perceived quality of life after maxillofacial prosthetic rehabilitation. Purpose The purpose of this study was to evaluate patients' perceptions of treatment with adhesive-retained and implant-retained facial prostheses and to assess differences in overall satisfaction with these 2 types of treatments. Material and methods In this study, a questionnaire with 28 items was administered for evaluation of perceptions of appearance, comfort, fit and irritation, reliability of retention, frequency of wear, ease of placement and removal, level of self-consciousness, and value of treatment. Subjects were categorized into 2 groups: adhesive-retained group (n=16) and implant-retained group (n=19). Comparisons were made for each item in the questionnaire using Fisher exact tests (α=.05). Results The implant group reported higher positive ratings on all 28 questionnaire items when compared with the adhesive group. Statistically significant ( P Conclusion The implant-retained facial prosthesis offers significant enhancement over an adhesive-retained prosthesis with respect to ease of use and retention during a variety of daily activities, resulting in greater use of the prosthesis.

Abstract: Purpose This article presents a novel manufacturing approach that integrates laser surface digitizing/scanning and computer-aided design (CAD) and manufacturing (CAM) to achieve automated fabrication of spatially and anatomically accurate extraoral facial prostheses. Materials and methods Topologic data of the patient's face, including the site of deformity and the anatomy of a healthy "donor" organ, were acquired using laser surface digitizing. Two different CAD data manipulation techniques were developed to alleviate problems encountered in laser-digitized data sets. To reduce patient involvement, fitting of the prosthesis was conducted using a computer model of the patient's face. Once finalized, rapid prototyping techniques were employed to fabricate a master pattern to cast the final prosthesis. Results Three case studies involving different facial prostheses were conducted to evaluate the integrated manufacturing system. The results demonstrated the many advantages of the system for facial prosthesis production. Conclusion With the new manufacturing approach, reduced patient discomfort, minimal dependence on the artistic skills of the prosthetist, and short turnaround times for prosthesis production can be expected.

Abstract: We describe a technique for the design and fabrication of realistic facial prostheses using three-dimensional optical imaging and computer-aided design and manufacturing (CAD/CAM). A three-dimensional dataset of the facial surface of a patient who needed a facial prosthesis was obtained using a sensing system, and the three-dimensional image of the face was reconstructed. A decreased and thinned virtual prosthesis was designed based on the facial image and converted into a rapid prototyping wax prosthesis using a selective laser sintering technique. The rapid prototyping wax prosthesis was then dipped into melted base-plate wax which generated a layer of wax on the internal and external surfaces to record its size and thickness. The modified prosthesis was evaluated and refined, and processed to generate a realistic silicone prosthesis. Three-dimensional data acquisition using the sensing system and computer-assisted design and manufacture of the prosthesis allows us to see a whole face without damaging the soft tissues or causing discomfort to the patient or exposure to radiation. The final prosthesis was of satisfactory size, shape, and cosmetic appearance, matched the malformed area, and suited the patient's requirements.

Abstract: Purpose The conventional impression technique for manufacturing facial prostheses has the disadvantage of deforming the soft tissues because of the tension caused by the impression material, as well as causing discomfort to the patient. The purpose of this study was to establish a system that allows contact-free reproduction of the facial surface combined with computer-assisted design and fabrication of facial prostheses. Materials and methods Three-dimensional data of the facial surface were obtained using an optical acquisition system based on the method of phase-measuring profilometry. A sensor head with a fringe projector and two CCD cameras for photogrammetric triangulation were used in connection with a PC for measurement control and data evaluation. Software for computer-assisted design of the facial surface to be reconstructed was developed. A prototype facial prosthesis was fabricated using stereolithography. The system was tested using a modified puppet head. First clinical tests were performed with a patient who had undergone maxillofacial surgery including the resection of one eye. Results Three-dimensional data acquisition and imaging allow visualization of a whole face without causing tension or neuromuscular reaction. As surface brightness is also part of the digital model, it is even more realistic than a plaster cast. The stereolithographic object showed good marginal fit and satisfactory shape. Conclusion The presented technique allows three-dimensional data reproduction of the facial surface, computer-assisted design of a facial prosthesis, and transfer to a rapid prototyping unit. The system has obvious advantages over conventional impression techniques. Further clinical trials are planned to evaluate the clinical success of the technique.