We studied bone wound healing processes after maxillary molar extractions in ovariectomized (OVX) aged rats by means of scanning electron microscopy, quantitative backscattered electron image analysis, and energy-dispersive X-ray microanalysis. Six-month-old female rats were either sham operated or bilaterally OVX; and at 60 days postoperatively, the first molars were extracted. On post extraction days 4, 7, 30, and 60, the dissected maxillae were fixed and the extracted alveolar sockets examined. New bone formation in both sham operated control and OVX rats was recognized on the buccal bone surfaces, as well as within the extracted alveolar sockets, and increased daily until day 60. In comparison with controls, new bone formation in OVX rats was significantly decreased both on the buccal bone surfaces and within the extracted sockets. Both Ca and P weight percents in newly formed bone on the buccal side were also significantly decreased in OVX rats, but Ca/P molar ratio was similar between both groups. Ca and P weight percent and Ca/P molar ratios in newly formed bone within the extracted sockets similar between these two groups. On days 30 and 60, the wound healing of extracted alveolar sockets in OVX rats was delayed in comparison with controls. Bone resorption in OVX rats was greatly stimulated and comparatively long lasting. These results suggest that in bone wound healing after maxillary molar extraction, (1) bone formation and resorption take place at specific sites on alveolar bone surfaces, (2) OVX stimulates sustained bone resorption, and (3) bone formation is significantly decreased by OVX with respect to the extent and mineralization rate.

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The Mongoloids may be divided, even if roughly classified, into two groups : One is called the Sinodont and the other the Sundadont. It is said that the Jomon people with the Sundadont came to Japan about 10,000 years ago. Later, about 2,000 years ago, the Yayoi came to Japan with the Sinodont by way of the Korean Peninsula and racially mixed with the Jomon, resulting in today's formation of Japanese with Sinodont being predominant.
We therefore prepared upper jaw plaster casts of three races. The first is that of a Filipino belonging to the Sundadont race, the second of a Japanese belonging to the Sinodont race, and the third of a Chinese closely related with the origin of the Japanese. We then took three-dimensional measurements of the upper jaw plaster casts with a laser measuring device, SURFLACER Model VMS-150R-D (made by UNISN), and analyzed the results of these measurements for dental arch size and palatal depth (frontal section and sagittal section) with an image analyzer computer program, SURFACER (Imageware, Inc., USA), running on a personal computer. We then studied these analytical findings statistically.
As a result, the Japanese was found to be akin to the Chinese in many dental arch size related points and to the Filipino at the center of the frontal section and at the posterior parts of the sagittal section, both in the palate. And the Japanese was found to take an intermediate position between the Chinese and the Filipino in width of the dental arch at the second molar tooth. The Japanese was larger than either the Chinese or the Filipino in both anterior dental arch length and arch chord of canine.
A summary of what has been referred to above may be described in this way : The Japanese today have both dental arch size and palatal depth that represent a complicated racial mixture of factors predominantly seen in both the Chinese as a northern race and the Filipinos as a southern race. Nevertheless, the Japanese are akin to the Chinese in terms of dental arch size, showing factors predominantly observed in the northern race Yayoi, but to the Filipinos in palatal depth (at the center of the frontal section and at the posterior parts of the sagittal section), showing the factors predominantly seen in the southern Jomon race. Furthermore, it could be suggested that the Japanese with a mouth apt to protrude showed factors predominantly seen in the northern Yayoi race.

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In the case of oral surgery, the targets for blood transfusions are almost sagitally split between ramous osteotomy and the excision of malignant tumors. The increased attention to risks associated with homologous blood transfusions, such as human immunodeficiency virus, hepatitis, and graft versus host disease, have provided the impetus for homologous blood transfusions irradiated with 15-50 Gy and the use of autologous blood transfusions. However, we have not made good use of autologous blood transfusions for malignant tumor surgery.
We studied a total of 301 patients scheduled for malignant tumor surgery from January 1991 to August 1999. A total of 135 patients (about 45% of the cases) were given homologous blood transfusions. Autologous blood was proposed for hemodilutional autologous blood and predeposited autologous blood. In all cases in which the blood loss was less than 800 ml, we could avoid homologous blood transfusions for the use of autologous blood transfusion. In cases of blood loss exceeding 801 ml but less than 1,800 ml, about 50% of the patients could avoid homologous blood transfusions.
In malignant tumor surgery, the technique of a hemodilutional autologous blood transfusion with predeposited autologous blood transfusion is possible to decrease homologous blood transfusions and their risks.

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A case of adenoid cystic carcinoma successfully treated with systemic chemotherapy and radiation is reported. The patient was a 66-year-old woman with a large adenoid cystic carcinoma in the left pharynx that had recurred from the left mandibular region. The tumor invasion of the cranial basis was revealed by a coronal plane view of magnetic resonance imaging (MRI). She denied surgical excision, so treatment with chemotherapy and radiation therapy was selected. Systemic chemotherapy using cisplatin, 5-fluorouracil, pilarubicin, and cyclophosphamide was performed with occasional radiotherapy. After 4 such treatments, clinical and MRI findings disclosed a complete disappearance of the tumor.

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This report presents one orthodontic case using a friction-free bracket (3F bracket®) for treatment. The edgewise mechanism has several advantages because it controls tooth movement in three dimensions. However, its rectangular slot has a sizable disadvantage because the frictional force is between the bracket and the wire at the same time. Excessive friction between an edgewise bracket and the wire still remain a big problem in orthodontic clinics. Only friction-free brackets have enabled a tooth to move smoothly of equipping with a unique chaperon on which cylindrical or spherical shafts are mainly designed to control friction, without sacrificing their own ability to control torque. Therefore we discuss the effectiveness of this type of bracket through a case treated with one and suggested some clinical consideration and bracket design.

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A lipoma is a benign tumor derived from nonepithelial origin and may occur almost anywhere on the body. In the oral cavity, however, a lipoma is relatively rare.
In this report, 22 cases of lipoma treated in our department during the past 15 years are reviewed.

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