Surgical reconstructions are useful for the treatment of patients with facial defects caused by tumors and facial injuries. However, facial prostheses are desirable for some cases with facial defects of particular form and size.
There are different ways of fabricating facial prostheses depending on the defect area, retention method, and material used. This paper describes the various retention methods we use for facial prostheses and our process of making orbital prostheses. The facial defects which we repair are the whole or part of the nose, cheek, auricle and orbit. Undercuts of the defect, adhesive agents, and facial implants are used to retain the facial prostheses.
The methods used to fabricate orbital prostheses depend on the retention method. This paper presents our methods of fabricating implant-assisted facial prostheses, and examines the characteristics of silicone for facial prostheses.
The Okayama Yumeno-Kaiwa Project was established for restoring the speech of glossectomy patients in 2015 by the late Prof. Ken-ichi Kozaki, who was an oncologist, researcher and also a tongue-cancer patient. The outpatient clinic of this project provides tongue prosthesis treatment for total and subtotal glossectomy patients. Different from conventional palatal augmentation prosthesis （PAP）, a newly-developed PAP with flat palatal surface （Flat-PAP） is used to control the exhalation flow to restore the place for articulation. The silicone tongue prosthesis for subtotal glossectomy was manipulated by the residual tongue when the residual tongue had enough physical ability, and that for total glossectomy was controlled by jaw open-close movement. Both of these prostheses were most effective with the use of Flat-PAP. This article introduces the structure and concept of the tongue prosthesis.
Purposes: The maxillofacial prosthodontist should participate in maxillo-mandibular reconstructive surgery to achieve ideal prosthodontics through pre- to post-surgery. Reconstruction of the new jaw and alveolus based on various and simple surgical procedures. This article has reviewed the variation and characteristics for prosthodontics of such procedures.
Surgical Procedures: For framework reconstruction, there are four main procedures: no bridging, artifact, non-vascularized bone graft, and vascularized bone containing free flap. For the lining, there are four main procedures: direct closure of the remaining mucosa, secondary intension, skin paddle of the free flap, and skin graft. And a combination of these procedures is possible.
Case Presentations: A maxillofacial prosthodontist preoperatively made guide-splints of the ideal alveolus from the dental plaster cast, checked the position of the bone graft and intraoperatively reconstructed the alveolus using the guide-splint, postoperatively adjusted the splint for a better shape of the reconstructed alveolus, and finally set dentures in 2 cases.
Conclusions: Prosthodontics is only one of the goals of jaw reconstruction, but if it is planned pre-surgically for a patient, it should certainly be achieved. For better prosthodontics, a guide-splint making the jaw and alveolus in a top-down style is a good solution for prosthodontists and reconstructive surgeons.
Maxillary prostheses applied for acquired maxillary defects need specific considerations in order to rehabilitate oral functions. Abutment selections and their long term observations in our clinic are reviewed and discussed from a retrospective study. Factors contributing to the abutment prognosis of the maxillary prosthesis are defect size, number of remaining teeth, history of radiation therapy, and oral care.
Aim: To investigate the effect of chewing on body sway in patients wearing a dento-maxillary prosthesis.
Materials and Methods: The subjects were 17 patients who wore a dento-maxillary prosthesis after head and neck tumor resection. They were divided into two groups: maxillary prosthesis wearers （Group 1, 11 subjects） and mandibular prosthesis wearers （Group 2, 6 subjects）. Body sway while standing with eyes closed was measured by a computerized footboard in a static jaw position （habitual occlusal position with prosthesis） and a dynamic jaw position （gum chewing with prosthesis）. The environmental area, right-left distance, anterior-posterior distance, and total length of body sway were calculated and compared between the two jaw positions in each group by the Wilcoxon signed-rank test.
Results: The environmental area of body sway was significantly smaller in the dynamic jaw position than in the static jaw position in Group 1 （P＜0.033）. There was no significant difference in any of the body sway indices between the two jaw positions in Group 2.
Conclusions: Body sway tended to decrease during gum chewing in patients wearing a dento-maxillary prosthesis attached to the maxilla but not attached to the mandible.
This study aimed to evaluate the morphology of denture space in mandibular edentulous glossectomy patients by using piezography. Mandibular edentulous glossectomy （n＝6） and non-glossectomy （n＝7） patients were enrolled. To record the denture space of these patients, the piezography technique was used. Piezographic records were scanned by cone beam computed tomography and the data were converted into stereolithography format. The following parameters were measured: 1） the discrepancy between the midpoint of the labio-lingual edge and the crest of the residual alveolar ridge along the occlusal plane, and 2） the left and right areas bounded by the lingual surface divided at the midline. The ratios between the areas of the larger and smaller halves were calculated. The Mann–Whitney U test was used for statistical analysis.
The glossectomy group showed significantly greater discrepancy between the labio-lingual and alveolar crest points and the lingual area ratios than the control group. These comparisons reveal that piezographic records differ morphologically between mandibular edentulous patients with and without glossectomy. As a clinical implication, the denture space must be considered at the stage of prosthesis fabrication in mandibular edentulous glossectomy patients.
We have used the Epitec system to retain orbital maxillofacial prostheses for maxillofacial defects. Furthermore, we have used combined plates by performing laser welding of multiple Epitec plates for a facial prosthesis. We have evaluated several cases over the long term in which we used big plates for retaining the facial prostheses. In all cases, the Epitec plates have remained in place and are able to retain the prosthesis. In the first case, the plate was lost early on, so we changed the design and there has been no loss of plate since then. Based on our experience, we believe we have improved the Epitec system with laser welding of multiple plates as a stable retainer for maxillofacial prosthetic treatment. It is suggested that the design of the plate and the control of dermatitis are important long-term factors for functionalizing the plate.
Facial prostheses are a treatment option for patients who have severe facial defects owing to cancer, trauma, or congenital disease. Since restrictions were recently placed on acquiring silicone materials for facial prostheses, a domestic silicone material is required. In this study, a novel silicone relining material was applied for facial prostheses and compared with those fabricated from the conventional silicone material.
Eleven subjects used the facial prostheses with two kinds of silicone material for six months alternately. Informed consent was obtained prior to the study. Patients were asked to complete a questionnaire. After twelve months, the color differences and questionnaire answers were evaluated. The questionnaire included 16 questions which were classified into material, feeling, maintenance, esthetics, and overall evaluation.
Though slight color differences were found in both materials, the differences were not significant. In the subjective evaluation, the relining material was better as a material though there was no difference between both materials in terms of smell and humidity. No difference was found between both materials regarding maintenance. Overall, more subjects preferred to use facial prostheses made of the relining material. Though further observation is necessary, the relining material could be used for facial prostheses.
Soft palatal augmentation prosthesis （Soft PAP） is a newly developed device which improves speech quality by providing an articulation point for patients with functional or morphological imperfection of their tongue. Soft PAP was made with a thermoplastic plate molded on a working cast whose palatal shape was modified using silicone putty material to make a flat surface on the palate. This article introduces fabrication procedures of three types of Soft PAP.
Patients with maxillofacial defect after radiotherapy frequently suffer from trismus. Trismus makes it difficult to fabricate a maxillofacial prosthesis. In the present case, we attempted to improve xerostomia, articulation, mastication and swallowing with a three-piece maxillofacial prosthesis for a patient who had widespread maxillofacial defects and severe trismus. The patient was a 58-year-old man who had undergone heavy particle therapy due to osteosarcoma at the right maxilla three years before the first visit to our hospital. In spite of widespread maxillofacial defects on the right mid-face and maxilla caused by tissue necrosis, the prosthesis covered only the facial defects. Therefore, he suffered from severe xerostomia, dysarthria, trismus, dysmasesis and dysphagia. We aimed to fabricate a new maxillofacial prosthesis for tightly sealing the oral cavity and nasal cavity. This prosthesis was designed to have three parts （palatal plate, obturator and facial prosthesis） because of the severe trismus and complex form of the maxillofacial defects. The palatal plate and obturator were connected by magnetic attachments, and the facial prosthesis was connected with an obturator by the fitting structure. This prosthesis significantly improved xerostomia, articulation, mastication and swallowing.