C-fos expression was used to determine areas at which neurons were excited by electrical stimulation of the tooth pulp in the cat forebrain. Tooth pulp stimulation (0.2msec duration, twin pulse) was delivered at 1 Hz under pentobarbital sodium anesthesia (35㎎/kg) and the intensity was maintained at 3 times the threshold for the jaw-opening reflex (200-600μA). With a survival time of 1.5 hrs following the start of stimulation, cats were perfused with buffered paraformaldehyde. Brain slices were incubated with polyclonal rabbit antibody against the Fos protein that originated in c-fos and was processed according to the peroxidase-antiperoxidase (PAP) method. In the pentobarbital sodium-inlected (35㎎/0.7ml/kg, 2 hrs before sacrifice) group, Fos-positive neurons were found bilaterally in the prelimbic, infralimbic, prepiriform, perirhinal, periamygdaloid and entorhinal cortices, lateral habenular (HbL), thalamic and hypothalamic paraventricular nuclei, supraoptic nucleus (SON), infundibular nucleus and anterior preoptic area. Furthermore, tooth pulp stimulation resulted bilaterally in Fos expression in the granular insula and increased the number of Fos-positive neurons to 368% in SON and 280% in HbL. In addition, the increases were inhibited by morphine administration (2㎎/kg, i.p.). These findings suggest that SON and HbL are involved in defensive mechanisms to noxious stimulation through the release of vasopressin and antinociception.

This experimental study was designed to investigate the cytotoxicity of pure titanium, titanium nitride, titanium alloy and stainless steel in vitro using an MC840106 cell line established from mouse calvarial bones. The cytotoxicity evaluation in this study was based on the cell growth rate, incorporation of ³H-thymidine and cell morphological changes by light microscopic and scanning electron microscopic observations.

The results may be summarized as follows: 1. Pure titanium, titanium nitride, titanium alloy and stainless steel had no significant cytotoxic action on cell morphologies and extensions. 2. In cell growth rates in the presence of the metals, there were no significant differences compared with the control. However, titanium alloy and stainless steel tended to decrease the cell growth rate. An excellent growth rate was obtained with titanium nitride. 3. Pure titanium, titanium nitride and the control produced no significant differences in incorporation of ³H-thymidine into DNA. However, the incorporation of ³H-thymidine was significantly inhibited by titanium alloy and stainless steel compared to control. 4. On examining the elution of metallic elements from the metal plates into a culture medium, titanium elements were detected in the culture medium containing pure titanium, titanium nitride or titanium alloy. However, the elution of titanium elements from titanium nitride was negligible compared with pure titanium and titanium alloy. Aluminum or a ferrous element was detected on titanium alloy and stainless steel. Other elements were less than the limits of detection. The above results may suggest that titanium nitride is a very useful biomaterial.

This study was designed to investigate how the personal characters of children and the attitude of their mothers toward upbringing of their children were related to the adaptability (cooperativeness) and inadaptability (aversion) of children to dental treatment. The subjects consisted of a total of 131 children (70 boys and 61 girls), aged from 3 to less than 6 years and their mothers. The children were divided into four age-groups, and each group was subdivided into adaptable and maladaptable groups according to behavior of children during dental treatment. The adaptability was evaluated with a total of 23 character-indices in psychological tests. The following results were obtained: There were no differences between adaptable and maladaptable groups and between the boys and girls in the character-indices of children aged 3 to less than 3.5 years. However, differences began to appear between the adaptable and maladaptable groups with the advance of age. The boys of the maladaptable group began to garadually manifest undesirable character-indices.

“Individual instability” constituted an item of poor characteristics in the indices of children aged 3 to less than 3.5 years. The item continued to extend over 3.5 years. “Social instability” developed with age. The attitude of mothers in upbringing already showed poor percentile in lower-aged boys of the maladaption group. The poor items in attitude of the mothers toward upbringing consisited of “intervention pattern”, “dotage pattern” and “disapproval pattern for children of lower ages. With the advance of age, “intervention pattern” and “anxiety pattern” still played minor roles in the upbringing of children except in the girls of the adaptable group. It seemed that the maladaptability to dental treatment was triggered by being subjected to frequent dental treatment at a lower age and was associated with the personal character of individual children at higher ages and inappropriate attitude of their mothers.

This paper describes our experience in general anesthesia for a patient with 3p trisomy. 3p trisomy is caused by a chromosomal aberration due to the partial trisomy of the short arm of chromosome 3. The patient, a 9-year-old girl weighing 25kg, was scheduled for dental treatment under general anesthesia. She had the characteristic face of 3p trisomy and complications of mental retardation, muscle weakness, and PDA (post-operative). After premedication with atroplne (0.25㎎), anesthesia was induced with thiamylal (150㎎) and vecuronium bromide (2.5㎎) and maintained with sevoflurane in nitrous oxide and oxygen. Mask ventilation, laryngoscopy and intubation were easy. No remarkable changes were observed in the circulatory and respiratory systems. The duration of anesthesia was 3 hrs. On the basis of this experience, problems in the anesthetic management of 3p trisomy syndrome are discussed.

Peripheral facial nerve paralysis appeared in 4 of about 250 cases following sagittal splitting osteotomy of the mandibular ramus at the Department of Orthodontics, School of Dentistry, Iwate Medical University, during the past 27 years. The operation consisted of Obwegeser-Dal Pont’s osteotomy, Epker’s modification and Obwegeser’s osteotomy technique. Causes of peripheral facial nerve paralysis during the postoperative course were analyzed and determined on the basis of the location of the lesion and its symptoms, the method of operation, and the CT-Scanning findings. The following results were obtained: The complication in the first case was presumably attributable to the compression of the peripheral facial nerve due to the postoperative hematoma, as assessed by CT-Scanning two months after operation. The second case was suspected to have resulted from viral infection because the appearance of peripheral facial nerve paralysis became clearly perceptible 27 days after the operation. The third case was possibly due to the compression by postoperative edema or viral infection. The fourth case was perhaps due to direct surgical damage to the nerve.

Pathological examinations undertaken at our Department in 1991 were statistically reviewed. The number of biopsy materials amounted to a total of 474 from 349 cases (179 males and 170 females). In histological classifications of biopsy materials there were 17 odontogenic tumors. The non-odontogenic benign tumors consisted of 7 papillomas, 18 fibromas, 3hemangiomas, 11ymph angioma, 2 lipomas, 1 myxoma, 1 verrucous xanthoma, 6 pleomorphic adenomas and others. Also found were 36 cases of non-odontogenic malignancy which consisted of 27 squamous cell carcinomas, 3 melanomas, 3 verrucous carcinomas, 2 mucoepidermoid carcinomas and 1 other. The odontogenic cyst consisted of 26 radicular cysts, 6 primordial cysts, and 10 dentigerous cysts. The non-odontogenic cyst consisted of 4 incisive canal cysts, 32 postoperative maxillary cysts, and 28 mucoceles and others. In addition, 10 cases of hyperkeratosis (leukoplakia) and 95 cases of inflammatory lesions were found.