Gifu Shika Gakkai zasshi = The Journal of Gifu Dental Society最新文献

The color of visible light-cured composite resins was examined by a dental color meter. The color shade guide was used as reference material in this study. The color difference value ranged from 5.5 to 11.0, suggesting that the color of composite resins is out of range of the shade guide.

The biting force of the first permanent molar, from children in the first grade of elementary school to adults in their seventies, was measured in 1959 and in 1987. Comparison between these two sets of data showed no significant difference in each age. The biting force of the second milk molar of kindergarteners aged from 4 to 5 years old, showed a decrease of nearly 5 kilograms on the average and in particular. The number of the children whose biting force was less than 15 kilograms increase. There was a negative correlation between the depth of the periodontal pocket of every kind of tooth and the biting force, and the average of the correlation coefficient was about minus 0.3. Especially, there was negative correlation between the depth of the periodontal pocket of the first permanent molar of patients in their forties and their biting force.

Prosthetics for cases with large defects of alveolar bone often tend to be difficult. We researched the acoustic effects of various pontic forms to satisfy a patient's expectations for both phonetics and aesthetics.

Twenty young hybrid dogs were classified into 5 groups: the control, the group examined immediately after 2 weeks compression (3.52 mm), and those examined at 2, 4 and 8 weeks retention. In those animals undergoing compression 4 times, Dentaurum expansion screws (#602-813) were placed between the left and right fourth dento premolar. when rapid compression was used interruptedly, local synostosis was only seen in the palatine suture, but following retention for 8 weeks, this phenomenon almost completely disappeared. The internal mechanical force of the adjoining sutures had disappeared within 4 weeks of retention. In conclusion, this clinical application causes no permanent damage.

Functional effects of construction bite for activator (Andresen type) especially on lateral pterygoid muscle, as well as the positional changes of the mandible, hyoid bone and surface EMGs from bilateral anterior temporal (TA) and masseter (MM) muscle, were studied on the electric force scale, MKG, EMG and cephalometric radiographs in 14 subjects with anterior cross bite in mixed dentition. The cephalometric radiographs were taken at the start of each patient's treatment. One was taken with the mandible in the intercuspal position and one was also taken with the activator in the mouth at the overjet improvement. The activator patients were divided into two groups because of differences in the direction of movement of the hyoid bone in the FH plane. In group O (7 patients), the movement of the hyoid bone was at an oblique angle to the FH plane, while in group D (7 patients) the movement ot the hyoid bone with nearly direct below angle to FH plane. The patients were further divided into three types because of differences in the distance between the hyoid bone and mental spine, and combined with the groups OA (3 patients), OB (2 patients), OC (2 patients), DA (5 patients), DB (2 patients) and DC (Naught). The results obtained were as follows: The forces for the construction bite for groups O and D were 2.71 Kg and 2.72 kg, respectively. Type OC required significantly heavier force. (p less than 0.05) In the condylar test, O group was significantly smaller at the start of treatment, but not after overjet improvement. Type OA and OB were also significantly smaller at the start of treatment. (p less than 0.05) Velocity of opening for group D was significantly (p less than 0.05) faster at the start of treatment, but not after that. There was no significant difference in EMGs between the groups, with activator in the mouse D group much increased as it EMGs. The EMGs M/T ratio for both groups was approximately 100% at the start of treatment for overjet improvement. In cases with no or slight lateral shift in the recorded path of closure or in the incisal region, no large differences were recorded laterally. Large EMGs differences were recorded with lateral shift in the incisal region, especially when taking the construction bite.

We applied of granular hydroxyapatite HAP to periodontal bone defects, for the purpose of restoring the periodontal tissue destroyed by periodontal disease, the subjects were 6 patients (6 regions) with chronic marginal periodontitis who had passed more than 3 years since HAP implantation. After routine periodontal initial treatment, a flap operation was performed, and granular HAP, or a combination of granular and block-like HAP, was implanted into the periodontal bone defect. Clinical parameters were probing depth, clinical attachment level, clinical gingival margin, residual HAP volume and X-ray before operation, at 3, 6, 12 months, and 2, 3, and 4, 6 years after the operation. The results revealed that all measured values showed good results for both granular HAP and the combination of granular and block-like HAP after implantation, and that all cases showed stable results from 12 months on. No remarkable difference was noted between the implanted regions.