Aichi-Gakuin dental science最新文献

In 1941, the Ohguruwa remains were discovered at the Mizuho sports ground site in Nagoya. They date from about 3000 B.C., which is the early Jomon era. When the stadium was reconstructed in 1980, four human skeletons were found. Three of them, however, were in poor condition and moreover, were incomplete. However, the second skeleton was in good condition and could almost be reconstructed, and this skeleton (No. 2) was used for our study. It was found in the classic posture with arms and legs folded. Some pieces of a dog's skeleton were also discovered near the No. 2 skeleton's chest. This particular skeleton generally showed characteristics typical of the Jomon era. It had a stout structure and was judged to be a middle aged male because of the following features. There was considerable attrition of the occlusal surfaces on the remaining teeth. The teeth were worn flat, probably owing to the hard food and to their use as a tool. Both canines and first premolars of the upper and lower arches had been extracted in accordance with the custom of the time. Typical caries and localized periodontal breakdown were not observed, although there was horizontal alveolar bone loss, especially in the anterior regions. The mastoid process was extremely large and prominent. The lateral prominence of the mandible was developed. Analysis of lateral cephalogram revealed that the mandible was in the anterior position. The angles of SNA, SNB and ANB were 89.6 degrees, 89.2 degrees and 0.4 degrees, respectively. The skeletal pattern was definitive Class III. The adaptive changes in the teeth, their supporting tissues, temporomandibular joints and the related muscles--the harmonious masticatory system--were all estimated.

This study was designed to examine the influence of children's personality traits and parents' child-rearing attitudes on children's internal behaviors before and after treatment. As an indicator of emotional changes, polygraph data and particularly plethysmograms were compared with psychological analysis data of children's personality traits and parental child-rearing attitudes. The subjects were 40 children with slightly carious primary molars, who were out-patients at Aichi-Gakuin University Dental Hospital. The results show that the emotional changes of children undergoing dental procedures are, in fact, observed at the resting pre-treatment stage, and that they are influenced by various factors, including parental child-rearing attitudes and children's personality traits. More over, in the resting post-treatment stage, these factors impinge upon children's emotions in a more complicated manner.

When mechanical stress is applied, osteoblasts have shown to produce bone turnover stimulating hormones and enzymes like prostaglandin E2 (PGE2), cyclic AMP, alkaline phosphatase, and collagenase. Osteocalcin (bone Gla protein) is also a protein produced by osteoblasts to control bone metabolism. Thus, its production may also be stimulated by mechanical stress. The purpose of this investigation was to test if mechanical stress stimulates osteoblast-like cells to produce osteocalcin in vitro. The results suggest that osteocalcin production is stimulated at the initial stage of the culture by cyclic tension and relaxation force, and secretion may decrease with time.

A case of congenital aglossia was orthodontically treated and long-term retention was observed from the age of 15 to 27. The patient had congenital absence of three lower incisors, abnormally small mandible (micrognathia), severe overbite and a telescopic bite in the premolar region accompanied by an extremely narrow lower arch. Orthodontic treatment was begun when the patient was 15 years and 6 months old. The active treatment period was 2 years and 9 months. At the present time, nine years have passed since the end of the active treatment, and intercuspation between the upper and lower arches is still good. It is suggested that the maintenance of the lower arch width is essential for long-term retention in cases of congenital aglossia.

The Balance Index is a list of standards by which instructors can assess the postures and position in the clinical performance of dental students. The purpose of this study was to examine the basic reliability of clinical instructors' understanding and application of the Balance Index. Certain reference Balance Index standards (Back Vertical, Head Position, Elbow/Arm Position and Wrist Bend) were learned and applied by eighteen clinical instructors, and the effectiveness of one instructor training method was evaluated. The results indicated that a simple graphic and numerical presentation of the Balance Index can be a useful tool to help clinical instructors learn how to assess postural and positional balance. It was also found that a feedback exercise using measured, graded variations of performance imbalances is likely to promote higher intra-rater (and inter-rater) reliability for evaluation of certain postural/positional components of dental clinical performance.

We report here two cases of treatment of upper lip hemangioma in infants, in which the Nd:YAG laser had a significant therapeutic effect. Case 1 was a 3-month-old male with swelling of the upper lip as the chief complaint. After galvano-caustic was performed under general anesthesia, sclerosing agent injection therapy (6 times, total 4.5 ml) was continued for 2 months. But the tumor was still growing about 2 years later, so resection was performed with Nd:YAG laser under general anesthesia. Case 2 was a 1-month-old male, also with swelling of the upper lip as the chief complaint. Resection was performed with Nd:YAG laser under general anesthesia. But the tumor was still growing about 4 months later, so it was repeated. The patients made satisfactory prognosis. Histologically, the final diagnoses of two cases were capillary hemangioma.

Excellent results were obtained in mandibular reconstruction by using the skeletal pin fixation system. The remaining bone was fixed before segmental resection. Case 1 was a 35-year-old male with a cementifying fibroma in the 2/6 region. We used the HH type pin fixation system and Kirschner wire (diameter 3.0 mm) for the fixation of the mandibular resection end. Case 2 was a 51-year-old male with an ameloblastoma in the 6/4 region. We used the HY type pin fixation system before mandibular resection. Case 3 was a 45-year-old female with an ossifying fibroma in the 6/4 region. The same fixation system was used as in case 2. In all cases, mandibular reconstruction was carried out with iliac bone graft and A-O plate.

Alveolar bone turnover has two phases: bone resorption and formation. Bone resorption entails both mineral removal and collagenolysis. A pH decrease over the local bone surface is required for mineral removal. Both lactic acid and citric acid has been suggested as the acids which remove crystals. During the orthodontic movement of teeth, a process of overall bone resorption occurs during displacement, whereas at the retention stage this process needs to be stopped in order to stabilize the alveolar bone. Thus, lactic acid and citric acid may be valid parameters of bone resorption intensity. The purpose of this investigation is firstly to test if these acids can be detected in gingival fluid around the moving teeth, and secondly to find if any changes occur before, during and after orthodontic tooth movement. The results indicate that these acids can be good parameters which show how favorably tooth movement is proceeding. They also show how stable the teeth are when orthodontic force is stopped to apply.

A case of acinic cell carcinoma in the palate is reported here. Acinic cell carcinoma is a relatively rare type of adenocarcinoma of salivary gland origin. The patient, an 83-year-old male, complained of swelling in the palate. A red soft mass approximately 8 mm in diameter was noticed in the right maxillary first molar region. Histopathological diagnosis of the surgically removed specimen was acinic cell carcinoma. The tumor had invaded the maxilla. Surgical excision with a border of normal tissue seemed to be an effective form of treatment. The patient exhibited good clinical recovery without recurrence or metastasis.

The present study investigated the influence of surface treatments of composite materials using 6% hydrofluoric acid or 2% acidulated phosphate fluoride, the influence of the application of a bonding agent to the surface, and the influence of incremental curing of composite materials on the shear bonding strength between composite materials and resin cements. These results were studied statistically by analyzing variances in three-way classification and by their contributory ratios. The effects of hydrofluoric acids or acidulated phosphate fluorides on the treated surfaces of composite materials, and also the interfaces between composite materials and resin cements were further examined by mean of scanning electron microscopy (SEM). Unlike the controls, surfaces of all specimens treated with hydrofluoric acid or fluoride revealed micro-porous surfaces, but the effect of the surface treatment on the bonding strength was not equal for all the composite materials tested. The application of a bonding agent influenced some composite material, but the incremental curing of composite materials had no influence on bonding with resin cements.