Follow-up measurements of the abutment tooth mobility were carried out to examine the mobility changes for a long period of 12 to 14 years. The subjects were 6 patients, having 12 abutments and they were wearing mandibular unilateral distal extension partial dentures of the same design.
These results were as follows:
1) The tooth mobility of the abutment hadn’t increased exclusively by the wearing of the distal extension denture over a 10-year period. Among the 12 abutments, 7 abutments showed nearly the same degree of mobility as the initial level, and the mobility of the other 4 abutments increased slightly. However, one abutment alone was extracted because of severe increased mobility.
2) There was an extremely slight difference in the mobility between both abutments and the mobility of each abutment presented nearly the same amount. Also the tendency in the mobility change indicated a similar pattern.
3) The long-term prognosis of mandibular unilateral distal extension partial denture, of the most common clasp design, presented a favourable state during the 12 to 14 years, judging from the changes in the abutment mobility.
A two-dimensional echocardiographic examination was conducted on 184 patients with Kawasaki disease iteratively from the acute phase to the convalescent phase. Aneurysms or dilatation of the coronary arteries were observed in 37 patients (20.1%). Among these 37 patients, 22 had persistent abnormality even after eight weeks from the onset. In the remaining 15 patients, abnormal findings disappeared within eight weeks. Coronary angiography was performed on all of these 37 patients and compared with the findings of echocardiography. In consequence, echocardiographic findings were concordant with those of the angiography in 35 patients. Therefore, the two-dimension al echocardiographic examination is thought to be a reliable noninvasive method for evaluating the coronary arterial lesions of Kawasaki disease in the acute phase.
A new method for local drug delivery to the subgingival plaque was developed using hydroxypropylcellulose (HPC) as a base material. Using this material prepared in the form of strips containing antimicrobial drugs, the clinical and microbiological effects by this method on the human periodontal disease were studied.
Before the clinical trials, the rate of the drug release from the strips was studied. Both drugs used in this study (CH: chlorhexidine and TC: tetracycline) were released almost within 2 hours from the strips in vitro. In the gingival crevicular fluid, however, it was found that the TC was maintained for 24 hours after the local delivery.
Five patients who had deep pockets contralaterally were selected. The CH-containing HPC strips (5%) were applied in one pocket of each patient and the placebo strips were applied in other pocket on day 0, 2 and 4. Plaque Index, Gingival Index, probing depth and the presence or absence of bleeding on probing were recorded on day 0, 2, 4 and 6.
Marked reduction of bleeding on probing was found in the pockets applied the CH-containing HPC strips. There was a significant reduction in the proportion of Bacteroides asaccharolyticus in these pockets (p<0.01).
This study was conducted to study chemically and serologically the characteristics of the Ureaplasmas isolated from the human oral cavity. Two hundred and fifty-one healthy and 12 periodontitis subjects were examined for the incidence of the isolation of Ureaplasmas from their oral cavity. A total of twenty-six strains was isolated from the healthy human saliva. But no strains could be isolated from a variety of clinical specimens obtained from the patients. The serological properties of the isolates were tested by the method of metabolism inhibition test (MI test). Seven out of 26 isolates were serologically identical with either one of the ATCC standard strains. However, the serological types of the other strains could not be demonstrated by the MI test. The biological characteristics of 4 isolates and ATCC strains were tested by the usual method. The isolates did not metabolize glucose and arginine, while all strains hydrolyzed urea. On the other hand, none of the isolates lysed skimmed milk and gelatin. The proteolytic activity of the isolates could be demonstrated by using casein and horse serum proteins as substrates. Zymogram patterns from one of the isolates and Streptococcus salivarius were obtained by polyacrylamide gel electrophoresis of the cells lysed with digitonin or cell protein extracts. On the basis of the gel electrophoresis patterns, it is clear that the urease of the Ureapla.1ma is different from that of the Streptococcus salivarius.
The effects of CO2 laser irradiation on the premolar and molar vestibular gingiva of twenty-one mongrel dogs were studied. The relationship between the irradiated energy, damage due to the radiation and the healing process were observed macroscopically and microscopically. Bleeding was not observed during radiation. The ray did not reach the bone, and damages to the soft tissue could heal easily at less than 10 J irradiation. When the irradiation energy was increased higher than 20 J the healing process was significantly delayed, and irreversible damage to the tooth, partial loss of the alveolar crest and sequestra formation were observed in some cases.