In this multicenter study, the relationship between clinico-pathological factors and cervical lymph node metastasis in patients with squamous cell carcinoma of the tongue was investigated by multivariate analysis. Two hundred eighty patients with squamous cell carcinoma of the tongue were enrolled at five hospitals. The quantification theory, Type II of Hayashi, was employed for analysis. Analyses of all cases showed that the combined effects of factors such as histopathological mode of invasion, T category, site of the primary tumor, and clinical type were significantly related to the presence or absence of cervical lymph node metastasis. Moreover, each factor independently contributed to the presence of metastasis. The contribution of the category of each risk factor to metastasis (from strongest to weakest) was as follows: mode of invasion=4D, 4C, 3, and 2 or 1; T category=T4, T3, T2, and T1; clinical findings=elevated type, ulcerative type, granular type, and papillary or leukoplakic type; primary site=posterior type, mid type, and anterior type. Analyses of late cervical lymph node metastasis in Stage I and II cases showed that the combination of factors such as histopathological mode of invasion, clinical findings, and the presence or absence of involvement of the floor of the mouth, was significant in identifying metastasis. These results suggest that multivariate analysis might be useful in predicting cervical lymph node metastasis in squamous cell carcinoma of the tongue.
We immunohistochemically studied the relationship between E-cadherin expression and prognosis in 72 patients with primary oral squamous cell carcinoma. E-cadherin is expressed homogeneously with a typical membranous staining pattern at cell-cell borders in normal oral epithelium. Twenty-three of the 72 tumors studied had decreased (or lost) E-cadherin expression. Decreased (or lost) expression of E-cadherin closely correlated with the cancer differentiation grade and with clinical lymph node metastasis. Moreover, decreased (or lost) E-cadherin expression correlated with shorter patient survival. However, E-cadherin expression did not correlate with T category or clinical stage. Determination of E-cadherin expression in oral squamous cell carcinoma is therefore expected to provide useful information with regard to prognosis.
Whether allografting can be used to repair long-distance nerve defects caused by tumor resection is an open question. The purpose of this experimental study was to determine whether lyophilized allograft nerves can regenerate in a 40-mm nerve defect. Sciatic nerves were collected from New Zealand white rabbits and were processed to prepare lyophilized nerve grafts. The great auricular nerves were partially resected bilaterally from Japanese white rabbits, intended as recipients, and a 40-mm lyophilized nerve graft was transplanted to the defect of the left great auricular nerve. As control, a 40-mm autograft of the sciatic nerve was transplanted to the defect of the right great auricular nerve. Twelve, 18, 24, 30, and 48 weeks after the operation, regenerated nerve fibers at the distal region 10 mm from the peripheral end of the graft were stimulated by electrical pulses, and the action potential was recorded from the healthy sensory nerve bundle near the central end of the graft. The maximum values of the sensory nerve conduction velocity (S.C.V.) was then estimated. Semi- or ultra-thin transverse sections for morphological examination were prepared from the distal side of the graft embedded in spurr resin. The microscopic images of each section were processed with the use of computer software to determine the number of regenerated myelinated axons per unit area. The thickness of the myelin sheath, circumferences of the myelin sheath and the axon, and other variables were similarly measured using electron microscopic images of sections. The statistical significance of correlations among the morphological measurements and S.C.V. were compared between the allografting and the control sides. The circumferences of the myelin sheath and the axon were suggested to be indexes for functional recovery of the regenerated axon. The results indicated that allografting of lyophilized nerves was useful for the repair of long-distance nerve defects. The growth of a small bundle of several regenerated axons on the allograft side was characterized by compartmentalized perineurial cells that enclosed the regenerated nerve trunk.
Breakage of gloves during clinical examinations and surgery has been sporadically reported by various departments. We compared the frequency of breakage of vinyl gloves (VG) with that of latex gloves (LG) during the treatment of outpatients, since no such report has been published previously. We studied 627 pairs of VG (1254 gloves) and 495 pairs of LG (990 gloves) used for treatment in the outpatient clinic of our department. The breakage of VG and LG was compared with regard to the clinical experience of the physician the duration of treatment, the awareness of breakage, as well as the site, extent, and cause of breakage. A water leak test was employed to objectively examine used gloves. Breakage occurred in 27.0% of VG, which was about 4.4 times greater than the breakage rate for LG (6.1%). Breakage of VG was about twice as common for the left glove than for the right, but there was no difference for LG. With both/types of gloves, about 60% of the breaks were not detected during treatment, suggesting the risk of contamination of the surgical field by the fingers. The frequency of breakage of LG during dental treatment varies widely among departments, i. e., from 2.8 to 50%. With VG the most frequent site and cause of damage were needle injuries affecting the index finger of the left hand, whereas with LG the palm of the right hand was most frequently damaged by the needle holder. The fit and strength of gloves were problems with VG, while the breakage of LG was less common. Among physicians with 1 to 2 years' clinical experience, breakage was common despite a short duration of treatment, indicating that the utmost caution is required even when LG are used.
Odontogenic ghost cell tumor, considered to be a solid type of calcifying odontogenic cyst, is a rare entity, and only a few cases have been reported in the English and Japanese literature. Here, we report a case of odontogenic ghost cell tumor in a 59-year-old man. The patient presented with a painless swelling in the mandible. The swelling extended from the first right molar region to the ramus. Radiography revealed a relatively well defined radiolucent lesion containing some irregularly-shaped radiopaque masses and an impacted third molar. Segmental resection and reconstruction with an iliac cancellous bone graft and a titanium mesh plate were performed. Histopathologically, there was evidence of tumor invasion of the periphelial cortical bone, areas consisting of large amounts of calcifying flaky keratin close to masses of ghost cells, and dysplastic dentinoid matrix adjacent to epithelial cell nests. Atypical mitosis was not found. A final diagnosis of “central odontogenic ghost cell tumor” was made. Three years after operation, the patient is well with no signs of recurrence.
Erythema nodusum is a non-idiopathic type of inflammation localized in the subcutaneous adipose tissue. It extends mainly to the sides of the extensor muscles of the legs and is associated with red induration, swelling, myalgia, and arthralgia. This disease also has been associated with upper tracheal infection, Behcet's disease, and Crohn's disease. However, its pathogenesis remains unknown despite many studies. We report on a man who developed erythema nodusum associated with unknown fever and arthalgia. A large radicular cyst in the right side of the maxilla was suggested to be the cause of this disease, and the association between erythema nodusum and the infectious dental focus is described in this report.
We clinicostatistically studied 102 cases of external dental fistula at the Department of Oral and Maxillofacial Surgery, Asahikawa Medical College during the past 18 years (from 1977 through 1994). The following results were obtained: 1) The 102 patients comprised 49 males and 53 females. As for age, patients, in their twenties and thirties were most frequently encountered. 2) The period from the onset of disease until the first visit at our clinic tended to be relatively long. The longest period was 13 years and the shortest several days. The average period was 16.9 months. 3) The cheek area (48.0%) was the commonest site of external dental fistulae. 4) External dental fistula arose more often in the mandibular region than the maxillary region, and was especially frequent in the mandibular molars and incisors. 5) In many patients the involved teeth and the fistula were concurrently treated by surgery.
A case of retention cyst occurring in the buccal mucosa of a 45-year-old man is reported in this paper. The presented cyst was measured 3 cm in diameter and arose in the area from the retromolar region to left commissure of the lip. Intraoperative findings suggested that this lesion originated from the buccal salivary glands. Histopathological examination revealed a well-defined mucous cyst lined with squamous cell epithelium. The lesion was thereby diagnosed as a retention cyst.
Ten patients with dislocated condylar process fractures of the mandible who were treated by the method of the lag screw osteosynthesis as described by Eckelt are presented. A lag screw was introduced into the mandibular ramus with a periangular skin incision. This method has two major advantages: interfragmentary compression can be obtained for stability, and the articular region does not have to be re-exposed to remove the osteosynthetic material. Satisfactory results were obtained functionally and morphologically in seven patients in whom the screw accidentally deviated from the minor segment. One of the problems with this method is displacement of the lag screw from the minor segment. The other is that there is difficulty in removing the screw in some cases.