The majority of studies on speech production have focused on articulation disorders; little is known about changes to the characteristics of voice. The purposes of this study were twofold. 1. Examine the acoustic parameters of computer-based acoustic analysis systems to determine which parameters are suitable to evaluate voice production in clinical settings. 2. Apply practical parameters to mandibulectomy patients to reveal the characteristics of their voice production. Thirty-eight normal subjects; 19 mandibulectomy patients associated with neck dissection and 6 mandibulectomy patients without neck dissection participated in this study. All voices were analyzed using a Computerized Speech Lab CSL system 4400 （Kay PENTAX, Lincoln Park, NJ, USA） and Multi Dimensional Voice Program （MDVP） software. The Noise-to-Harmonic Ratio （NHR） was determined to be a useful index for clinical assessment of voice quality. NHR values were significantly different between normal subjects and mandibulectomy patients with neck dissection, and between mandibulectomy patients with neck dissection and mandibulectomy patients without neck dissection. It was thus suggested that the voice quality of the mandibulectomy patients with neck dissection might have been influenced by their medical treatment. The cause of a patient’s speech disorder possibly originates from both articulation and voice disorders.

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The purpose of this study was to construct an auricular shape database for making a prototype of an auricular prosthesis by using rapid prototyping technology. We extracted the auricular data from 3D-CT data at Hokkaido University Hospital in the past. Extracted data were interpolated and saved into the database in voxel format and STL format. 3D-CT data of 145 cases were surveyed and 70 cases, involving 130 auricular data, were selected. In addition, we tried to make a surgical template for auricular reconstruction at the request of a plastic surgeon, to be used for adjusting the cartilage of rib to the auricular shape. We used the shape data of the auricular database to make it and examined the problems.

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A facial prosthesis may have various problems with regard to retention. The use of osseointegrated implants improves retention, however, their application is limited in Japan. Hence, we propose the use of a new silicone material with adhesive characteristics for making a facial prosthesis. This article describes the properties of adhesive silicone and clinical application of a facial prosthesis made of adhesive silicone.
The adhesive silicone consists of base silicone and catalyst in the proportion of 60:1. It did not induce any skin reaction in the patch test and had sufficient adhesiveness in the rolling ball tag test. An 82-year-old woman and an 88-year-old man, who after surgery for tumor removal had defects in the nasal region, were treated. The man’s defect was reconstructed with his skin. Their nasal defects were reconstructed with facial prostheses made of medical grade silicone with adhesiveness. This type of facial prosthesis was successful in terms of retention and patient satisfaction. It is suggested that the prosthesis made of adhesive silicone could be applied in patients with facial defects.

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Radiotherapy for head and neck cancer is a significant modality compared to surgery in terms of QOL, because it can preserve the shape and functions of the head and neck region, but osteoradionecrosis is one of the most severe late adverse effects related to radiotherapy of the head and neck. In particular, the jaws, which are just covered with vulnerable alveolar mucosa, are easily exposed. Once infection occurs, osteomyelitis spreads rapidly because of impairment of bone remodeling resulting from damaged osteoblasts by irradiation, and leads to osteoradionecrosis via a chronic process. Osteoradionecrosis occurs more frequently in the mandible than in the maxilla, because the cortical bone is thicker and blood supply is less abundant in the mandible. In spite of the rare occurrence of osteoradionecrosis of the maxilla, necrotic bone that sequesters from the maxilla causes leakage of food and drink in the oral cavity into the nasal cavity, maxillary sinus and orbit, and thus markedly deteriorates QOL of patients. We report our experience of making a maxillofacial prosthesis repeatedly for progressive osteoradionecrosis of the maxilla resulting from radiotherapy for carcinoma of the maxillary sinus.

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When fabricating facial prostheses, artistic ability and sharp, observant eyes are essential. In Japan, maxillofacial prosthodontists and dental technicians fabricate facial prostheses based on their own experiences or senses. The purpose of this article is to analyze the current educational system in Japan and compare it to that of the United States.
A questionnaire survey of 25 dental schools and 441 dental technicians revealed that 72％ of dental schools and 24％ of dental technicians had had lectures on facial prostheses but had not had practical training. Regarding post-graduate programs, while prosthodontic departments had lectures in dental school, there were no standardized programs for facial prosthetics.
In the United States, specialists known as Medical Artists, who undergo a masters program after graduating from art and biology bachelor courses, fabricate facial prostheses. We introduce the curriculum and clinical experience of “Biomedical Visualization” at the University of Illinois, Chicago, one of the distinguished programs for medical artists in the US. The program for medical artists covers various spheres including both medical and artistic aspects. Our finding suggests that a global education on facial prosthetics could be beneficial in Japan and that capable specialists need to be developed.

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After maxillary antrostomy in a 72-year-old male, a defect in the maxillae remained without any prosthetic treatment for two years. A tampon prosthesis was very useful for the patient temporarily. A temporary obturator prosthesis was fabricated to restore function. After removing the fixed prosthesis in the right（defective bone side） upper molar region and extracting abutment teeth, a dento-maxillary prosthesis was fabricated. Rhinorrhea of saliva disturbed the patient while eating, because the prosthesis covered the parotid duct orifice which had moved upward due to the operation.
To solve this problem, we fabricated a definitive dento-maxillary prosthesis with a funnel-shaped obturator and a channel on the buccal surface of the prosthesis. The patient was satisfied with this dento-maxillary prosthesis functionally.

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From 2002 to 2007, three patients who had uncomfortable large subperiosteal implants were treated. These implants were made from titanium and fixed by screws, but had become infected and were accompanied with pain and swelling.
Case 1: 68-year-old female
Her edentulous mandible had been restored by a subperiosteal implant. She had severe pain when chewing and swelling around the implant. The implant was removed, and her edentulous jaws were restored by removable dentures.
Case 2: 67-year-old male
His edentulous maxilla had been restored by a subperiosteal implant. He had had pain and discomfort in the maxilla for a long time from implant placement. His implant was removed, the bone defect was reconstructed by a fibula bone flap, and 6 implants were placed in the maxilla, after which his dentition was restored by implant prostheses.
Case 3: 70-year-old female
Her edentulous maxilla had been restored by a subperiosteal implant. She had felt pain and discomfort after the surgery and it did not improve for 10 years. The implant was removed, and her maxilla was restored by a removable denture.
Subperiosteal implants must not be used for treatment of edentulous jaws.

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Although high-quality flexible facial prostheses have become available as a prosthetic repair for facial defects, the issues of the fitness and color matching of the prosthesis and patient’s skin tissue remain. This paper reports the trial of airbrush make-up for treating the facial prosthesis margin to improve the fitness at the margin of the prosthesis and the patient’s skin. The devices used for airbrush make-up were a spray brush and water-based foundation for paramedical use （Dinair Inc, U.S.A.）. After fixing the auricular prosthesis, Flesh Effect Gel （Ben Nye Company, U.S.A.）, of which the major ingredient is gelatin, was applied at the site of fixation and marginal area. Use of the gel reduced the burden on the skin at the site of prosthesis fixation, and also filled the gap at the margin.
Airbrush make-up can be easily applied by patients themselves without any special knowledge. The gel fills the gap at the margin and is easy to handle for the patients. An airbrush can also be used for coloring the facial prosthesis. The mist spray-on method is the optimal way to express the fine texture of the Japanese skin.

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