The present paper reports the expression of tumor suppressor gene product p53 in biopsy specimens obtained from 40 cases of oral squamous cell carcinoma, studied by optimal immunohistochemical technique. The results are compared with those derived by immunohistochemical detection of PCNA (PC 10) and their relation ship with clinicopathologic findings is also described.
Immunohistochemical expression with monoclonal antibodies (BP 53-12) to p53 showed positive staining in 21 cases (52%).
In these cases, evidence of p53 was significantly correlated with positive reaction to PCNA (P<0.01).
Moreover, the expression of p53 was positively correlated with histopathological signs of malignancy such as the mode of invasion and degree of histological differentiation.

View full abstract

Squamous cell carcinoma related antigen (SCC-Ag) and carcinoembryonic antigen (CEA) were respectively estimated by radioimmunoassay of serum samples obtained from 35 and 42 untreated patients with oral squamous cell carcinomas. The expression of SCC-Ag and CEA in the tumor tissue was also investigated immunohistochemically.
Pathologic serum SCC-Ag levels in excess of the cut-off value (1.5 ng/ml) were observed in 37.1% of the patients. The serum SCC-Ag level correlated positively with clinical staging and tumor size according to the TNM classification and the degree of SCC-Ag expression on tumor cells, but did not correlate with the degree of differentiation, and the mode and stage of invasion. Furthermore, serial measurements of the serum SCC-Ag level revealed good and rapid responses to treatment. In contrast, elevated serum CEA levels over the cut-off value of 2.5 ng/ml were observed only in 11.9% of the patients. The serum CEA level did not show any correlation with clinical staging or other variables.
Thus, the determination of serum SCC-Ag level was of clinical value in the pretherapeutic staging and post-therapeutic monitoring of disease, although it was not useful for the detection of early signs of disease. Compared with SCC-Ag, CEA was less useful as a tumor marker of oral squamous cell carcinomas.

View full abstract

Simulative experiments of sagittal splitting osteotomy of the mandibular ramus were undertaken using dentate human air-dried mandibular bones. The distribution of dynamic strain was measured.
The following results were obtained:
(1) The absolute value of dynamic strain tended to be lower in sagittal splitting osteotomy by Obwegeser's technique than by the Obwegeser-Dal Pont method.
(2) In sagittal splitting osteotomy by Obwegeser's technique the absolute value of dynamic strain directly beneath the mylohyoid neural groove was unrelated to the kind or application angle of the osteotome or other splitting instruments.
(3) In sagittal splitting osteotomy by the Obwegeser-Dal Pont's technique, high dynamicstrain was recorded directly beneath the mylohyoid neural groove, except when osteotomy was carried out with a splitter inserted at a 60° angle. These findings suggest a risk of accidental fracture due to concentrated stress in this region occurring when the osteotome is not used properly.
(4) These experiments suggested that sagittal splitting osteotomy of the mandible can be accomplished with a higher margin of safety by Obwegeser's technique than by the Obwegeser-Dal Pont's technique because of lower stress concentration with the former.

View full abstract

Recently, lasers operating at shorter and shorter wavelengths have become available. The excimer laser emits pulses of ultraviolet irradiation. The KrF excimer laser has high incision efficiency, and can cut hard tissue without thermal damage.
Use of a laser in the oral region is dangerous due to the close proximity between the operative field and the tracheal tube. Evaluation of the influence of laser irradiation on tracheal tubes is therefore necessary.
The authors assessed the effects of KrF excimer laser irradiation on Portex^®, Spiral tube^® and Diffencer^® tracheal tubes under ordinary atmospheric conditions, and gas flow rates of 3l/min for both O₂ and N₂O. The laser was used at energy densities of 40 and 60 J/cm², frequencies of 20 and 40Hz, a beam spot of 0.015 cm², a pulse width of 15 ns, and a peak power of 2.7 MW.
The tubes was perforated by laser irradiation under ordinary atmospheric conditions, but they did not ignite. The time required for perforation of the tubes became shorter as the energy density and frequency increased. The perforation time under the flow of O₂ 3l/min and N₂ O 3l/min was comparable to that under ordinaly atmospheric conditions. Spiral tube^® ignited almost simultaneously to the time of perforation at energy densities of 40 and 60J/cm² and a frequency of 40Hz.

View full abstract

In the regeneration of peripheral nerves, Schwann cells guide the direction of regenerated axons.
This study was designed to observe axonal regeneration under the following conditions:
(1) The presence of viable Schwann cells;
(2) The presence of viable Schwann cell basal lamina alone; and
(3) The absence of all viable tissue components.
The experimental groups were prepared as follows and the process of axonal regeneration was examined by transmission electron microscopy.
(1) The sciatic nerves of rat were transected and sutured. The nerve segments were observed in the distal stump.
(2) The sciatic nerves of rats were excised and grafted to lyophilized homologus nerves.
(3) Similarly, the sciatic nerves were excised. Polyglycolic acid (P. G. A.) fibers were inserted in silicone tubes and grafted to the nerve gaps.
The results were as follows:
1. In the distal stump which underwent transection and suture of nerve fibers, Schwann cells phagocytized degenerating myelin sheaths and cell debris and guided regenerating axons.
2. In the lyophilized homologous nerve grafts, degenerated myelin sheaths and cell debris were phagocytized by macrophages, but the Schwann cell basal lamina remained.
3. In the lyophilized homologous nerve grafts, regenerating axons grew in contact with the inner surface of the basal lamina scaffolds of the Schwann cells.
4. In the tubulization group, regenerated axons were near the P. G. A. fibers and accompanied by Schwann cells.
These findings indicate that the basal lamina scaffolds of Schwann cells function as pathways for guiding the direction of regenerating axons and Schwann cells.

View full abstract

Skeletal malocclusion and orthognathic surgery may significantly influence the morphology and function of the temporomandibular joint and the position or direction of the mandibular condyle, thereby altering temporomandibular joint symptoms and signs or jaw function.
Forty patients (15 males and 25 females, aged 18-36 years and followed for 18-46 months) with facial deformities and major malocclusions were studied. The subjects included 37 cases of mandibular prognathia, 10 cases of facial asymmetry and 7 cases of open bite. All cases underwent sagittal splitting osteotomy. Each patient was reviewed to elucidate the factors involved in temporomandibular joint symptoms and mandibular dysfunction by Type I and Type 11 quantitative theory.
All signs and symptons of temporomandibular joint and mandibular dysfunction were recorded just before orthognathic surgery and at more than 18 months after surgery.
Analyses were performed using the external criterion of ‘TMJ score’ for Type I quantification and three categories of external criteria (i. e., ‘no symptoms’, ‘mainly TMJ symptoms’.‘mainly muscle symptoms’) for Type II quantification. The explanatory variables were ‘surgical method’, ‘bone fixation’, ‘operator’, ‘increase of overjet’, ‘increase of overbite’, ‘increase of difference between upper and lower jaw midlines’, ‘presurgical mandibular deviation of jaw opening’, ‘presurgical TMJ sound’, ‘presurgical TMJ pain’ and ‘presurgical muscular pain’.
The results were as follows:
1. Type I quantitative theory analysis revealed that postsurgical TMJ scores were most closely related to the factor of ‘operator’, and strongly related to increase of difference between upper and lower jaw midlines.
2. Type 11 quantitative theory analysis showed that the main symptoms of the cases were affected dominantly by the factor of ‘operator’, followed by the factors of ‘presurgical muscle pain’ and ‘increase of difference between upper and lower midlines’.
3. Strong correlation of the ‘operator’ and ‘increase of difference between upper and lower midlines’ with temporomandibular joint symptoms and dysfunction suggests that technical factors of the surgical procedure and facial asymmetry significantly affect the quantity and quality of temporomandibular joint symptoms.

View full abstract

In this study, the relationship between the healing process of pedicle skin flap and diabetic microangiopathy was examined in streptozotocin-induced diabetic rats. Experimental groups divided into 8 weeks and 16 weeks after induction of diabetic rat and non-injected rats were used as control Skin flaps in this study were prepared as a 1×3cm caudally based flap on the dorsal skin, and the animals were sacrificed at postoperative 3, 5, 7 days and 2 weeks, respectively.
Serial histological slides were stained with hematoxylin-eosin for light microscopey and microcorrosion casts were prepared for SEM by Ohta's plastic injection method.
Control group: three days after operation epithelialization was complete at the suture line and many inflammatory cells and undifferentiated mesenchymal cells appeared. New sinusoidal capillaries sprouted from the pre-existing dermal vessels. Five days after operation, blood vessels in the flap partially anastomosed with those of the host via new sinusoidal capillaries. Seven days and 2 weeks after operation, subdermal capillary networks gradually rearranged similar to a normal pattern.
Experimental groups: The healing process of the 8 week diabetic group was similar to that of the control group. In the 16-week diabetic group, five days after operation epithelialization was incomplete and new sinusoidal capillaries sprouting from the dermal vessels did not anastomose with those from the pre-existing vessels of the host. Seven days after operation, microvascular anastomoses were observed between capillaries of the flap and the host. Two weeks after operation, new sinusoidal capillaries still remained at the suture line and subdermal capillary networks did not show a normal pattern.
In conclusion, microvascular anastomosis of the subdermal capillary network between the flap and host was one important factor for the take of pedicle skin flaps. The healing process of the pedicle skin flap in diabetic rats was close! in proportion to the progression of microangiopathy.

View full abstract

In this report, 20 cases of oral lipoma treated in the First Department of Oral Surgery, Kyushu Dental College between 1978 and 1992 are reviewed. Included were two congenital cases and two multiple cases. Histologically, there were 10 simple lipomas, 9 fibrolipomas and angiolipoma.
Oral lipoma is no longer a rare tumor, and over 230 cases have been reported in Japan. Among 236 oral lipomas in Japan, simple lipomas appeared more frequently in malepatients (male: female ratio 116: 76), while fibrolipomas were more common in female (male: female ratio 14: 30). The patient sex distribution between simple lipomas and fibrolipomas was significantly different (X²-tcst, P<0.005).

View full abstract

A case of bilateral condlar neck fractures caused by indirect impact from the mental region in a 4-year-old boy is reported. The patient was hospitalized immediately after sustaining injury. On the third hospital day, manipulative reduction and intermaxillary fixation were performed under general anesthesia. Postoperative radiography revealed poor reduction of the right condyle, although the left condyle was favorably positioned. Intermaxillary fixation was done for a days without any postoperative complications. Both occlusion and mandibular motility during mouth opening were good by the 13 th hospital day. The patient has been followed up by physical and radiographic examinations for more than 3 years. The deviated right condyle was found to be correctly positioned within the glenoid fossa 16 months postoperatively. The upright position of the condylar neck was enabled by repositioning and osteo-remodelling.

View full abstract

Fifteen closed lock cases (fifteen joints) of internal derangement of the temporomandibular joint (TMJ) were treated by lavage manipulation technique. This technique involves manipulation after irrigation of the upper compartment of the affected TMJ with 200-400 ml lactated Ringer's solution followed by an injection of sodium hyaluronate (SPH) into the upper compartment.
In our case study, 11 of the 15 cases (73%) satisfied our criteria for successful treatment. MR imaging showed that only 2 (18%) of the 11 successful cases achieved complete reduction of the disk. In the remaining 9 cases, a significant range of mandibular motion was obtained by the condylar head sliding down under the anteriorly displaced disk during maximal mouth opening.
This technique was highly effective in relieving pain, as well as improving limited mouth opening. By this technique we were able to release a closed lock case which could not be opened by the pumping manipulation technique. These results suggest that the lavage manipulation technique is a more useful form of nonsurgical treatment than the pumping manipulation technique for releasing closed lock disturbances in outpatients without hospitalization.

View full abstract

Two rare cases of spontaneously discharged sialoliths are reported.
Case 1: A 72-year-old man was referred to our clinic for painless swelling in the right submandibular region. Radiographic examination revealed an opaque mass in the right Wharton's duct. Although we recommended surgical treatment, he refused. Twenty months later, he came for re-examination bringing with him a sialolith. The sialolith had been spontaneously discharged from the right side of the oral floor. The size of the stone was 30×20×15mm. The form was egg-shaped, the surface was rough, and the color was yellowish white.
Case 2: The patient was a 54-year-old woman complaining of swelling in the right submandibular region. Radiographic examination revealed a sialolith in the right Wharton's duct. The sialolith had been spontaneously discharged from the right side of the oral floor 2 weeks after her first visit. The size of the stone was 15×9×6mm. The form was eggshaped, the surface was rough, and the color was yellowish white.
The sialolith was examined with a scanning electron microscope equipped with an electron probe X-ray microanalyzer. The cut surface of the stone consisted of concentric layers sorrounding a single central core. Calcium, phosphorus, and sulphur were detected as the main components of the sialolith.

View full abstract

Pleomorphic adenoma is the most common salivary gland tumor and it usually appears between the ages of 20 and 50 years. Few cases occur in childhood and pleomorphic adenoma rarely develops on the palate.
We encountered a pleomorphic adenoma which had developed on the hard palate of a 10-year-old boy. The tumor was a semispherical mass measuring 20×20mm and situated in the posterior part of the right hard palate. Its surface was covered with smooth and normal mucosa. The tumor had an elastic hardness and was not mobile. There was no spontaneous pain or tenderness. Under a diagnosis of pleomorphic adenoma based on biopsy findings, the tumor was excised together with a surrounding safety margin of tissue (5mm) under general anesthesia. The removed tumor was oval and well encapsulated, and the cut surface was whitish grey and solid. The palatal bone was resorbed due to compression by the tumor. A layer of the bone in the resorbed area was scraped out and the wound was dressed with a stent. The tumor has not recurred since the operation.

View full abstract

We report a tongue abscess which was suspected to be a tumorous lesion clinicopathologically.
The patient was a 62-year-old male. He noticed painless swelling in left sublingual region and came to our department. Pathological examination of a biopsy specimen led to a diagnosis “Metastatic squamous cell carcinoma suspected”. However, as other examinations did not reveal any signs of the tumor in other organs, we removed the entire tongue lesion under local anesthesia. Tumor tissue was not found in the pathological specimens.
The origin of the epithelial components noted in the tongue abscess at biopsy is discussed.

View full abstract

Our experience with Webster cheiloplasty for reconstruction of the lower lip follwing radical excision of squamous cell carcinoma is described. This technique is a modification of Bernard cheiloplasty and simpler than other techniques such as double cross lip flap. Webster cheiloplasty can be used to cover defects involving as much as the entire lower lip. Relatively good to excellent cosmetic and function results were achieved.

View full abstract

Von Recklingllausen's disease is a syndrome defined by the presence of cafb-au-lait spots and multiple benign neurofibroma. Oral involvement is relatively rare in von Recklinghausen's neurofibromatosis. We experienced one case of von Recklinghausen's neurofibroma on the hard palate.

View full abstract

Despite advances in cancer therapy, it is very difficult to treat patients with leukopenia because of consequent infection. Recently, recombinant human granulocyte-colony stimulating factor (rhG-CSF) has been developed to enhance neutrophil number and function and thereby improve leukopenia. In this paper, we report our experience in treating a gingival carcinoma patient with autoimmune leukopenia by combination therapy with rhG-CSF.
A 53-year-old female patient with leukopenia (WBC 1, 200/mm³) was referred to our clinic and diagnosed as having lower gingival carcinoma (T2NOMO, Stage II). Laboratory data suggested that the leukopenia was due to autoimmunity. Since bone marrow aspiration showed a normal profile and a trial dose of rhG-CSF increased WBC rapidly, we decided to perform tumor excision and postoperative combined chemotherapy with rhG-CSF. Treatment with rhG-CSF in a dose of 2 μg/kg per day subcutaneously was done in three periods. The first period was for 14 days starting from 1 day before operation. After surgery two cycles were given. The first cycle was for 10 days starting on the day after terminating chemotherapy with CDDP and PEP, and the second cycle was for 16 days. WBC was maintanined at 10, 000-20, 000 cells/mm³ during rhG-CSF treatment. Postoperative infection and chemotherapy-related side effects were not noted.

View full abstract