Polymorphonuclear leukocytes (PMNs) were isolated from the mandible infection models in NZW rabbits. The effects of new quinolones on their migration were evaluated. New quinolones were ofloxacin (OFLX), lomefloxacin (LFLX), tosufloxacintosilate (TFLX), fleroxacin (FLRX), sparfloxacin (SPFX), and levofloxacin (LVFX), which are now used in the field of clinical dentistry. The results were as follows:
1) In the inoculation group, those that received no antimicrobial therapy showed an acceleration of PMN migration. This phenomenon observed three and seven days after inoculation was more significant than that observed before inoculation.
2) When no antimicrobials were administered PMN migration observed in the inoculation group was different from that observed in the control group. The levels of acceleration of PMN migration measured three and seven days after inoculation were 1.16 and 1, 10 times more significant than those measured in the control group.
3) The six antimicrobials were administered in various concentrations to evaluate their effects on PMN migration before inoculation OFLX in the concentration of 1μg/ml rarely affected PMN migration and that in the concentration of 10μg/ml accelerated PMN migration remarkably. OFLX in the high concentration of 100μg/ml significantly inhibited PMN migration. Similar tendencies were observed in the experiments using the remaining five antimicrobials.

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It was assumed that local anesthetics might act on proteins nonspecifically and that the effects of local anesthesia might be the result of such actions. Using Na, K-ATPase as a model, the effects of lidocaine, procaine, and dibucaine on Na, K-ATPase activity was studied to test our hypothesis. Na, K-ATPase from rabbit brain and kidney and rat brain was partially purified and Na, K-ATPase activity was determined by measurement of inorganic phosphate production by Chifflet's method. Lidocaine, procaine, and dibucaine inhibited all Na, K-ATPase activities, depending on their concentrations. The inhibition by lidocaine was complete at the concentration for its clinical usage. IC₅₀ values, which are the concentrations to give the half maximal inhibition, were determined for each anesthetic and the enzyme. The anesthetic with strong local anesthetic action and toxicity gave a smaller IC₅₀ value. The IC₅₀ values of each anesthetic for rabbit brain and kidney and rat brain were similar. As the concentration-dependent inhibition curves were sigmoidal, they were analyzed by the Hill plot. The Hill coefficients of all the anesthetics and the enzymes were around 0.4 to 0.6, suggesting negative cooperation between the binding sites for local anesthetics. These results support our hypothesis mentioned above.

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Green tea catechins have been widely used as an anticariogenic or antiplaque additive to mouthrinses, toothpastes, etc. Since their retention in the oral cavity is the determinant for thecaries preventive effects, the oral pharmacokinetic study was performed by assessing salivary concentrations of catechins with time after oral application using high-performance liquid chromatography with diode array detection. The optimized method enabled to simultaneously quantify eight catechins in the concentration range of 0.05-25.0μg/ml in saliva and mouthrinses with high resolution, recovery, and precision. Mouthrinsing experiments with the aqueous solutions of green tea extract (5.0mg/ml) revealed that each catechin maintained the salivary concentration at μg/ml levels for 1-60 min after mouthrinsing, especially (-) -epigal-locatechin gallate and (-) -gallocatechin gallate showed concentrations over 10μg/ml even after 60 min. When using the commercially available mouthrinses containing green tea extract, catechins were found in saliva up to 60 min after mouthrinsing, although their salivary concentrations were much lower. The retentive degree of catechins depended on their concentrations in mouthrinses and the number of times of mouthrinsing. Mouthrinsing with the green tea extract solution under optimal conditions would retain catechins in the oral cavity at least for 60 min after oral application, maintaining their salivary concentrations to show the potential caries preventive effects.

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Green tea catechins with the anticariogenic activity have been recently revealed to maintain their salivary concentrations after mouthrinsing. The mechanism underlying such retention in the oral cavity was studied by quantitatively evaluating the adsorption of catechins after vortex-mixing with hydroxyapatite, buccal mucosal cells, and proteins in artificial saliva. Treatment with hydroxyapatite decreased catechins in supernatants and such a decrease was more significant by coating hydroxyapatite with saliva as an experimental pellicle. When treating with mucosal cells, unwashed cells decreased catechins in ultrafiltrates more significantly than washed cells. Catechins in ultrafiltrates were decreased by treating with albumin and mucin depending on protein concentrations. These reduced concentrations in supernatants and ultrafiltrates meant the adsorption of catechins to hydroxyapatite, mucosal cells, and proteins. In structural comparison, four gallate esters were superior in the adsorptive activity to the corresponding non-esters. Concentration changes of salivary ctechins after mouthrinsing with green tea extracts showed that the retention of catechins in the oral cavity was associated with their adsorption. The present results suggested that green tea catechins are adsorbed by the teeth, pellicles and oral mucosa, and that salivary proteins such as albumin and mucin are responsible for the adsorption. The adsorbed catechins are considered to gradually be released to maintain the salivary concentrations after oral application.

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There have been few reports on the effects of interdental brush with toothpaste on periodontitis. Therefore, the purpose of this study was to evaluate the effects of interdental brush with toothpaste containing cetylpyridinium chloride (CPC) on adult periodontitis with the deep periodontal pocket. Twenty patients (experimental group: 10 subjects, control group: 10 subjects) who had not received general and/or local antibiotics prior to this study were selected. They had at least 1 tooth with over 5 mm of probing pocket depth on the mesial or distal side of maxillar or mandibular incisors and first premolars without a prosthesis, and they had not undergone professional periodontal treatment. The experimental group was instructed to use a toothbrush and an interdental brush with commercial toothpaste containing 0.05 % CPC, and the control group was instructed to use a toothbrush with toothpaste and an interdental brush without toothpaste. The amount of gingival cervical fluid (GCF), ratio of subgingival microflora, probing depth (PD), clinical attachment level (AL), and plaque score for adjacent teeth (P1S) were measured at baseline, and after 2 and 4 weeks. There were no statistical differences in PD, AL, GCF, and P1S between the experimental and control groups at any period. In bacterial study, both groups did not show significant change at any time. The results suggested that CPC does not infiltrate into the bottom of a deep periodontal pocket and does not have pharmacological effects. Thus further investigation of the method of administering CPC to the deep periodontal pocket should be conducted.

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The effects of Murraya extract on caries was examined in an experimental caries model, using golden hamsters (N=30) . The animals were divided into three groups, experimental group 1 (given the caries promoting diet (D# 2000) added 0.1 % Murraya extract and tap water) experimental group 2 (given D#2000 and tap water added 0.1 % Murraya extract) and control group (given D#2000 and tap water) . The two experimental groups showed lower caries scores than the control group. When the caries scores among the experimental groups were compared, experimental group 2 showed a lower caries score than experimental group 1.
These results suggested that Murraya extract could be useful for inhibiting dental caries.

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Twenty-two blood samples after tooth extraction with administration of clindamycin-2-phosphate intravenously were cultured with Bactec NR16A^® and NR17A^® (Becton Dickinson, Maryland, U. S. A.) . The strains were identified and each MIC of clindamycin was measured, and the serum concentrations of clindamycin were determined. The incidence rate of bacteremia in 12 cases out of 22 rated 54.5 %. Fifteen strains were isolated from 12 patients ; 7 were aerobic and 8 were anaerobic. MICs of clindamycin for isolated organisms were under 0.20μ g/ml. The serum levels of clindamycin were ≥2.88μg/ml, and the concentration was sufficient for each isolate.
The AHA (American Heart Association) and BSAC (the Endocarditis Working Party of the British Society for Antimicrobial Chemotherapy) recommend the use of clindamycin as prophylaxis of post tooth extraction for the patients who are allergic to penicillin. However, these results reveal that clindamycin is insufficient for the prevention of transient bacteremia after tooth extraction. It is suggested that the bactericidal activity of clindamycin is insufficient in a short time.

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