Appropriate mid-facial reference planes for evaluating the facial asymmetry of patients with maxillofacial defects have not been established, although several methods for setting mid-facial planes have been reported. The aim of this study was to examine the validity of mid-facial planes for evaluating facial asymmetry by three-dimensional （3D） angular and linear measurement in six normal subjects' faces with a non-contact 3D-digitizer and 3D scanning software. Four mid-facial planes were defined based on medial angles of the eye （MAE）, lateral angles of the eye （LAE）, dorsum of the nose （DN）, and superimposed image of original and mirror image （SI）. Distances between 10 measurement points including three bilateral pairs and mid-facial planes, angles between three measurement lines and mid-facial planes, and asymmetry indices of three pairs of measurement points were calculated. The asymmetry index of the corner of the mouth to MAE was significantly higher than that to SI. There was no significant difference among the parameters to LAE, DN and SI. The results suggested that the LAE, DN and SI can be used as reliable reference mid-facial planes for evaluating facial asymmetry. Furthermore, it would be necessary to select an appropriate mid-facial reference plane depending on the available reference points and therapeutic purpose of individual clinical cases.

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Although several reports have described masticatory function in post-maxillectomy patients with edentulous maxillae, there are no published results concerning food-mixing ability in these patients. This study therefore investigated the mixing ability in post-maxillectomy patients with edentulous maxillae.
A total of 10 subjects with edentulous maxillae who had undergone maxillectomy were selected. The subjects were divided into four groups, according to Aramany’s classifications I, II, IV and VI. The Mixing Ability Index （MAI） was evaluated on the basis of a food-mixing ability test.
MAIs were higher in class II patients than in other classes. In class IV patients, lower MAIs were associated with fewer mandibular teeth. Among the class VI patients, the MAI for subject 10, who underwent reconstruction with fibula bone, was highest and was similar to the MAIs for classes I and IV. This suggests that reconstruction with fibula bone could improve masticatory function in class IV patients.
The mixing ability test allowed objective evaluation of the food-mixing ability in post-maxillectomy patients with edentulous maxillae.

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The aim of this study was to conduct research on the present status of dento-maxillary prosthetic treatment for patients with maxillary defects in Japan.
The questionnaire was sent to 450 institutions. Out of 450 institutions, 137 answered the questionnaire. Eighty-eight institutions had patients who were treated with dento-maxillary prostheses. A totally of 2,542 cases with maxillary defects were treated in these 88 institutions in the last 5 years.
Four institutions answered that fabrication for dento-maxillary prostheses needed less than 4 treatment steps, 39 institutions answered 5 steps, 31 institutions answered 6 to 7 steps, and 11 institutions answered more than 8 steps.
Fifteen institutions answered that 1.5 times more material was used in the fabrication of dento-maxillary prostheses compared with conventional removable maxillary dentures, and 70 institutions answered that greater than 2.0 times more material was needed. Twenty-two institutions answered that fabrication of dento-maxillary prostheses needed 1.5 times the working hours compared with conventional removable maxillary dentures, and sixty-two institutions answered more than 2 times.
The greatest problem of prosthetic treatment for maxillary defects is the low treatment fee of these procedures in spite of the amount of work required, amount of material and long treatment time to fabricate dento-maxillary prostheses.

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In patients with tumor in mandibular region, the postoperative recovery process of swallowing ability might be affected by surgical resection, reconstruction, prosthetic treatment, and those effects might differ depending on postoperative days. We conducted a longitudinal analysis of possible factors that influence the swallowing ability of each postoperative stage. Swallowing ability was measured by time required to swallow 30 ml of water in 44 patients with tumor in mandibular regions before and 1, 3, 6, and 12 months after surgery. Multiple regression analysis was performed with difference between preoperative and postoperative swallowing ability of each follow-up time to identify possible factors influencing the postoperative recovery level of swallowing ability. Preoperative water-swallowing time predicted functional recovery in each follow-up time, suggesting the need to measure it preoperatively. Concerning the tumor treatment factors, neck dissection was demonstrated to decrease the recovery level of swallowing ability, but the number of occlusal support including that reconstructed by prosthetic procedures and chemotherapy were shown to increase the recovery level of swallowing ability after surgery, suggesting the efficacy of early prosthetic intervention. The study results would help in obtaining informed consent and provide efficient and farsighted rehabilitation in patients with tumor in mandibular region.

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Conventional methods for facial impression modeling can be uncomfortable for patients and the weight of the impression material can cause inaccuracy in fabricating facial prosthesis. Recently, several rapid prototyping systems have been introduced as simpler modeling methods, eliminating to need to make an impression. In this study, we evaluated three kinds of data acquisition systems in terms of accuracy and usability prior to clinical application in fabricating facial prosthesis.
Three subjects with symmetric facial curvature participated in this study. Informed consent was obtained for each subject. Three kinds of data were obtained using a laser scanning digitizer, a photogrammetric system, and a white-light phase-shifting triangulation system, respectively. Actual measurement of the face was performed simultaneously based on the pre-established landmarks. Those images were compared using model analyzing software.
All systems showed well accuracy. No significant difference was noted among the data acquisition systems and actual measurements. The laser scanning digitizer required the longest measurement time, which might cause motion artifact, while the photogrammetric system required the shortest measurement time.
This study demonstrates that each measurement system is reliable for fabricating facial prosthesis.

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Palatal Augmentation Prosthesis: PAP is effective for dysphagia due to tongue disorder after resection of oral tumor, but the evidences are not less shown or the mechanism of effect are not demonstrated yet either.
This presentation draws a comparison about the status and dysphagia diagnosis after operation between the 19 cases of rehabilitation using Palatal Augmentation Prosthesis and the 19 cases of that not using one after oral cancer surgery in 178 patients.
The results showed the relationship between method of reconstruction and PAP rehabilitation.
In conclusion, the results of this study suggest that indication of PAP depends on appropriate choice of flap for the defect.

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A silicone facial prosthesis made for a patient and worn for 5 years was reported. The patient was a 71 years old female, who had a left-side facial defect. After complete dentures had been fabricated, a facial prosthesis was fabricated of silicone and an obstacle frame was used for its retention. She returned once a year for the first 3 years for her dentures to be checked and her prosthesis repainted. Then, 5 years from the delivery of the facial prosthesis, she returned to have it repaired. The inner surface of the prosthesis, having been exposed to exhalated breath, showed partial black discoloration.
The surface topography of the inner surface of another prosthesis made from the same mold used for the one worn in this case was observed by SEM. The area of the duplicated prosthesis corresponding to the blackened one of the worn prosthesis showed a rough surface; whereas, the area corresponding to the non-discolored area in the worn prosthesis showed a smooth surface.
These findings suggest that the inner surface of a silicone facial prosthesis, which is constantly exposed to exhalated breath should be smoothed or relined with other materials for a long-lasting sanitary status.

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Ready-to-use applicators and spacers are available for radiotherapy. However, there are cases in which a more sophisticated device is required to meet highly specific therapeutic needs: cases such as in the maxillofacial region, where radiation is applied in a tightly defined site, which is part of a complex structure, or cases where a precise distance must be maintained between the irradiation source and target. Here, we report a prosthetic appliance that we have fabricated for a patient with palatal cancer. The prosthetic appliance, inserted with 192Ir small radiation sources, was for intracavitary irradiation of his oral cancer. No sign of recurrence and metastasis was noted 9 months after treatment.

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