[in Japanese]

View full abstract

pocampal aging process. This was done by investigating the morphological structure of the hippocampus, which plays an important role in learning and memory function throughout life.
Methods: Senescence accelerated mouse prone 8//Ymi (SAMP8//Ymi) at 2 months old, which were established as a murine model of aging with defect in learning and memory, were used in this study. Thirty male SAMP 8//Ymi at 2 months old were divided equally into 6 groups. Three groups were kept until 3 (young adult), 5 (middle age), and 8 (old age) months old (normal condition). The remaining three groups, in which their maxillary molar teeth were extracted at 2 months old, were kept until 3, 5, and 8 months old (molarless condition). When they reached the above-mentioned ages, their brains were rapidly removed from the skull, fixed in 10% buffered neutral formalin and processed routinely for paraffin embedding. The coronal sections, 6 Jim thick, cut at the hippocampal level, were stained with Nissl staining. We measured the number of pyramidal cells and the area of single cells within a defined frame in the hippocampal CA3 field.
Results: The mice with molar teeth at 8 months old showed a significant decrease in the number of pyramidal cells and area of single cells compared with the mice with molar teeth at 3 and 5 months old. The mice without molar teeth at 5 and 8 months old showed a significant decrease in the number and size of pyramidal cells compared with the mice without molar teeth at 3 months old. The mice without molar teeth showed a significant decrease in the number of pyramidal cells and area of single cells compared with the mice with molar teeth at 5 months old. However, there is no significant difference at 3 and 8 months old between the above two groups.
Conclusions: In SAMP 8//Ymi, molar teeth loss accelerated an age-related decrease in the number and size of hippocampal CA3 pyramidal cells. Thus it was suggested from the present study that molar teeth loss might play an important role in the morphological changes of the brain as a result of aging.

View full abstract

Health promotion in aged edentulous patients by encouraging the use of dentures is important for developing an energetic graying society. The masticatory function in those patients is improved by wearing dentures, increasing their daily life activity, and improving their physical, mental, and social health.
In this study, with regard to the improvement of QOL, complaints about dentures and symptoms by patients wearing complete dentures, including the causes and social factors, were investigated using a questionnaire, and the following results were obtained.
1. Patients wearing complete dentures showed negative correlations between their age and QOL factors. Significant correlations were observed among all the QOL factors.
2. The scores of all the factors in patients wearing dentures for 5 years were significantly higher than those in patients wearing dentures for 6 months.
3. Patients wearing dentures for 6 months showed correlations between the height of the mandibular bone, and the activity regarding QOL factors. Patients wearing dentures for 5 years showed correlations between the height of the mandibular bone, and the function and speech regarding QOL factors.
4. As a result of factor analysis (Varimax rotation method), a questionnaire about dentures consisting of 4 criteria such as functional, speech, aesthetic, and activity and psychological factors, which were classified into 27 items, was produced.

View full abstract

A case of a patient who lost consciousness during home-visit dental treatment is reported.
The patient was a 78-year-old female with a chief complaint of occlusal dysfunction. The patient's medical history was diabetes, hypertension, hyperlipidemia, or right hemiplegia, dementia, and depression due to cerebral hemorrhage and infarction.
At the first home-visit intraoral examination, production of upper and lower partial dentures was planned. In consultation with the physician in charge of the patient, it was suggested that in cases when local anesthetics containing epinephrine are used, it is necessary to monitor preoperative and postoperative blood pressure. The home-visit dental treatment from the first through fifth visits were performed without incident.
During trial denture fitting using wax dentures at the sixth home-visit dental treatment, the patient suddenly fell from the chair and lost consciousness. Approximately 10 seconds later, the patient showed a slight reaction when her name was called, and after several minutes, the patient regained her normal state and was able to speak. The operator observed the conditions of the patient for approxi- mately 40 minutes, and after confirming that there were no abnormalities in her general condition, he left the patient's house.
Neurogenic shock by the stress during trial denture fitting was thought to cause the loss of consciousness reported here, since the patient's decreased cognitive ability by dementia prevented her from sufficiently understanding the treatment, although repetitive transient ischemic attack (TIA) and symptomatic epilepsy were also suggested as a cause.
Furthermore, it was possible that propranolol, which the patient orally took on the morning before the treatment, induced the neurogenic shock.
These results suggest that, in home-visit dental treatment, sufficient attention must be paid to the dependent elderly whose physical reserve force has diminished even during procedures, such as trial denture fitting, which are not usually considered stressful.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract