Satsuki Hagiwara

Evaluation of bleeding on probing and gingival crevicular fluid enzyme activity for detection of periodontally active sites during supportive periodontal therapy

This study aimed to analyze the enzyme activity in gingival crevicular fluid (GCF) and its association with clinical parameters, especially bleeding on probing (BOP), and thus reconsider the significance and accuracy of recording BOP. A total of 184 patients who had entered supportive periodontal therapy were selected and GCF was collected from 401 sites before recording the clinical parameters, probing pocket depth (PPD), BOP, clinical attachment level, gingival index and plaque index. The enzyme activity of neutrophil elastase and aspartate aminotransferase and amount of protein in GCF were also analyzed. In the clinical parameters for biochemical data, amount of GCF showed the most correlation. A cut-off value for BOP and PPD were determined by the ROC curve and Youden index. Analysis was performed with all clinical parameters and biochemical data. Of the 401 sites, 51 were less than the cut-off value and were BOP-negative. On the other hand, 29 sites had values more than the cut-off value, with 14 BOP-negative sites and 15 BOP-positive sites. A conclusion is as follows: twenty-nine sites with values more than the cut-off value were diagnosed as sites requiring periodontal management, however, 14 of these were BOP-negative. These results suggest that combining other biochemical tests with examination of BOP and PPD may improve the validity of periodontal disease diagnosis. In future studies, it will be essential to find a marker that can precisely detect periodontal disease activity, and to develop a diagnostic tool for chair-side use.

Prevalence of Periodontal Disease in 15-year-old Schoolchildren in Japan

The purpose of this study was to determine the prevalence of periodontal disease in 690 15-year-old school children, living in Tokyo, Japan. This clinical survey was performed prior to the roentogenografic examination which was intended to study the prevalence of marginal bone loss.Plaque Index (by Silness and Loe) and Gingival Index (by Loe and Silness) were recorded on maxillary right first molar, left incisor, first premolar, mandibular left first molar, right premolar and right incisor. Pocket depth was measured in mm at the six teeth, maxillary and mandibular first molars, and incisors on the mesial sides. Bleeding Index during probing (by Ainamo) was also recorded.The means of the Plaque Index were 1.00 and 1.30 in girl and boy students respectively. The girl students were statistically superior (p<0.05) than the boys in oral prophylaxis. About 60 per cent of the children exhibited gingival inflammation as indicated more than 1.00 of Gingival Index. Very severe inflammation more than 2.00 of Gingival Index was observed about 1 per cent among the school children. About 30 per cent of the examined teeth showed pockets deeper than 2mm. About 10 per cent of the examined teeth were bleeded on probing.These results suggest that periodontal breakdown was occured on more than 10 per cent the 15-year-old school children. Periodontal care and education are necessary to early teen aged children.

スケーリング・ルートプレーニングの有効性に関する臨床的, 細菌学的研究

The aim of the present study was to monitor longitudinally the clinical and microbiological parameters after root debridement in order to determine the factors affecting successful and unsuccessful results. Nine patients with moderate and severe periodontitis participated. Four sites of single root with over 5-mm periodontal pockets in each quadrant were selected. The oral hygiene was controlled in all patients, then root debridement was performed without anesthesia at the three sites of the quadrants every two weeks during eight weeks. The clinical parameters consisted of plaque index, gingival index, probing depth, clinical attachment level, bleeding on probing, tooth mobility and the value of gingival crevicular fluid (GCF). The microbiological parameters such as percentages of cocci, motile rods, non-motile rods and spirochetes and the number of microorganisms were examined and the percentages of black pigmented Bacteroides (BPB) and Actinobacillus actinomycetemcomitans as well as the number of anaerobic colonies were counted. The results demonstrated that a reduction in the probing depth was observed in all sites except four. The successful sites clinically showed a decrease of the probing depth and GCF value and, microbiologically, reduced percentages of the spirochetes and BPB. The results indicated that the decrease of the probing depth and GCF under 50 Periotoron units in coincidence with the bacterial reduction can be used to determine the successful response of root debridement.

Epidemiological survey on dental prophylaxis and treatment by questionnaire. Primary report

A questionnaire concerning “the awareness of oral health and dental treatments in the past one year”was sent to 4, 000 persons in general (Group A) and 1, 000 bank clerks (Group B) .Of the two groups, 35.5 percent of the persons in general and 62.4 percent of the bank clerks answered the questionnaire.The answers to the questionnaire on the epidemiological survey of the periodontal disease of the two groups have been reported previously.The findings on the condition of the various dental treatments are described in this report.1) In Group A, the percentage of the subjects who received restoration by filling, crown or post-crown in the past one year was 32%, 23% and 9%, respectively. The mean number of teeth in a subject who was treated by filling, crown or post-crown was 2. 2, 1.9 and 2. 1, respectively.2) In Group A, the percentage of the subjects whose teeth were extracted was 16% and the mean number of extracted teeth was 2.7. The percentage and the number increased with age after the age of 35. Both the percentage of the subjects whose teeth were extracted in the past one year and the mean number of extracted teeth in Group B were much smaller than those in Group A.3) In Group A, the percentage of the subjects who received treatment for fixed bridge, removable partial denture (maxilla or mandibulla) or complete denture (maxilla or mandibulla) was 9%, 3 to 4% and 0.2 to 0.6%, respectively.These data will help to reveal the current status of the various dental treatments in Japan.

Possible Role of Lysosomal Enzymes in Process of Periodontal Destruction

The aim of this study was to observe whether the lysosomal enzymes from human polymorphonuclear leukocytes were capable of destroying periodontal tissue in vivo, when the enzymes were applied into the rabbit gingival sulcus.Human leukocytes were prepared by sedimentation of heparinized blood. A granule fraction was extracted from homogenate of leukocytes by centrifugation. The granule extract was obtained by freezing and thawing and subsequent centrifugation. A neutral protease of the granule extract was partially purified by a gel chromatography. From the result of biochemical analysis, it was found that the neutral protease fraction exhibited both proteolytic and elastolytic activities. The optimum pH of the neutral protease was approximately 8.3-8.9 with regard to its proteolytic activity. The molecular weight of the enzyme was estimated as 25, 000±3, 000 by a gel chromatography.All rabbits were given the drinking water containing 0.05% tetracycline hydrochloride for two weeks prior to the experiment to decrease the microorganisms in the crevices. Labial crevices of mandibular incisors of rabbits were used as experimental sites. The strips of filter papar were inserted into those crevices, then the granule extract and the neutral protease were dropped on the filter papar every ten minutes for six hours by tubercline syringe. Saline solution and the heat-inactivated enzymes were used as controls.Histological findings at experimental sites showed the ulceration of sulcular epithelium and inflammatory exudation in lamina propria. Leukocytic infiltrations into the epithelium were also observed especially at the site where the granule extract was applied. The connective tissue was slightly damaged in the neighborhood of the inflammatory cells at the experimental sites. Inflammatory alterations were hardly found at the three comparable regions of the control sites. The possibility of the direct or indirect destructive effects of lysosomal enzymes on periodontal tissues was indicated by this study.