The conventional facial impression technique involves inaccuracy of alginate impression material and distortion of facial surface topology due to the weight of the impression material. A non-contact three-dimensional （3-D） digitizer enables a surface configuration to be acquired in a few seconds. The aim of this study was to evaluate the conventional facial impression using a 3-D digitizer, VIVID 910. Facial impressions were taken on three volunteers with alginate and fast setting plaster, and laser surface scanning of the subject’s face was also performed by the 3-D digitizer on the same day. Cast facial models were fabricated and then laser scanned. Each morphological data was overlapped and amounts of discrepancy were analyzed on the various facial points and using data processing software. As a result, the amounts of discrepancy were found to vary depending on facial points. The discrepancy of the cheek area was greater than that of the forehead area. Those areas were compressed on the facial models, whereas the orbital area on the facial models was swollen compared to the laser scanned facial surface. In conclusion, the facial model made by the conventional facial impression technique includes area dependent size errors. The relatively thin skin area underlined by bone was more accurate than thick soft tissue area.

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We reported that the primary stage of calcification on the bone/titanium interface was affected by the amount of radiation exposure. In this study, we used pure Ti and treated Ti and observed the primary calcification on the surface of the materials when osteoblasts were irradiated in vitro.
Pure titanium disks were employed. Some samples were anodized in an electrolytic solution and hydrothermal treatment was conducted at 300℃ for 2 hours. Bone marrow cells were obtained from Wistar rats. For primary cultures, the femora was removed and washed with α-Minimal Essential Medium. Aliquots of the rat bone marrow cell suspension were cultured for 5 days and irradiated. The first subcultures were maintained up to 14 days. Cultures were fixed, dehydrated through a graded series of ethanol, and freeze dried with t-butyl alcohol. Specimens were observed either under SEM or an electron probe microanalyser. Furthermore, some specimens were used for quantitative analyses.
Irradiation doses under 0.4 Gy induced no significant changes of the primary stage of calcification on the bone/titanium interface. Calcification rates for 4 Gy were significantly different from the control and under 0.4 mGy samples. Calcification rates for treated titanium were significantly different from pure titanium under 0.4 Gy. （198 words）

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We studied the progress of 11 cases treated from January 1997 to December 2005 by orbital prostheses that were retained with the Epitec ^TM system.
Some of the small Epitec plates used in the first period showed instability due to insufficient primary fixation. Nevertheless, primary fixation of the Epitec plates improved as the plate size was enlarged in the second and third periods; installed plates remained stable for a long time even in cases in which high doses of irradiation were applied.
The success rate in all Epitec plates was 80.9 % excluding case 2 in which the plates were removed due to tumor metastasis. Of the respective treatment periods, the success rate in the first period was 70 %, the second 100 % and the third 85.7 %. The success rate in the irradiation group was 77.8 % against 100 % in the non-irradiation group. These results are comparable with other success rates reported in facial implants.
In conclusion, the Epitec ^TM system has proved to provide effective materials for the retention of orbital prostheses.

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This study reviewed our experience in the surgical treatment and reconstruction methods following tumor ablation for tongue cancer, and evaluated 212 cases （average: 57 yrs, range from 21-87 yrs） for 17 years from 1984 to 2002.
The 5-year cumulative survival rate was 83 % （Stage I: 96 %, II: 91 %, III: 85 %, IV: 67 %）, and flaps survived completely in 93.5 % （43/46 cases） in radial forearm free flap （RFFF）, 90.2% （46/51 cases） in rectus abdominis free flap （RAFF）, and 97.6% （40/41 cases） in pectoralis major myocutaneous flap （PMMC）.
The reconstruction methods were as follows:
1. Partial glossectomy; Simple suturing.
2. Hemiglossectomy limited to mobile tongue: RFFF was the first choice, and PMMC was selected in order to reduce the risk for severely medically compromised patients.
3. Subtotal, total glossectomy: RAFF was the first choice, and PMMC was also selected for severely medically compromised patients.
4. Regardless of which flap was selected, it was very important for postoperative oral function to select a flap larger than the size of the defect by glossectomy.
Conclusion: For better postoperative recovery, minimally invasive surgery is mostly recommendable. To guarantee successful tumor ablation followed by effective reconstruction, exact diagnosis by means of FDG-PET and PET-CT would be the key.

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After a malignant tumor has been excised in the mouth, the form dentures required is complex and cleaning is technically difficult. The maxillofacial prosthetic clinic at our university provides a team approach to rehabilitation that includes a dental surgeon, prosthodontist, dental technician and dental hygienist. The hygienist works closely in advising the patient concerning daily oral hygiene.
In this report, the state of plaque control in dento-maxillary prosthesis wearers was evaluated by using O’Leary’s plaque control record （PCR） before / after instruction by an oral hygienist. The state of denture plaque control was evaluated by the extent of dyed area on the polished surface of the obturator, retainers and artificial teeth where denture plaque tends to accumulate. A questionnaire survey on the oral hygiene habit was also carried out.
As a result, PCR and denture plaque were greatly improved by oral hygiene guidance. In the questionnaire, it was found that special oral hygiene management by the dental hygienist corresponding to each patient was important in improving mouth cleaning techniques and awareness. However, a significant difference was not found between the common denture group and the dentures for defective jaw group.

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