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Notes: Mixtures of neon or helium with alkali vapor were excited using an argon ion beam. The emission continua observed in the vacuum ultraviolet region between 60 and 80 nm are assigned to the decay of the ionic excimers He+K, He+Na, He+Li, Ne+Rb, Ne+K, Ne+Na, and Ne+Li into the ground state consisting of a rare gas atom and an alkali ion. The binding energies of these excimers range between 0.46 and 0.85 eV. The obtained decay energies and the fine structure splittings agree with the predictions by calculations using phenomenological potentials and by ab initio calculations. Intense emission due to the inner shell excitation of K and Rb is also observed.

Notes: Abstract The objectives of the present study were to establish in a long-term investigation the safety as well as the clinical and microbiological efficacy of scaling and rootplaning combined with local application of 2% minocycline hydro-chloride-gel versus placebo-gel in patients with moderate to severe chronic adult periodontitis. This was an 18 months, randomized, double-blind, parallel, comparative study, in which 20 healthy patients with moderate to severe chronic periodontitis participated. At baseline, all patients received professional oral hygiene instruction and supra-and subgingival scaling and root planing. The minocycline-gel was applied subgingivally baseline, 2 weeks. 1, 3, 6, 9 and 12 months. Microbiological evaluation was carried out using DMDx to identify the following bacteria: Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans. Campylobacter rectus. Fusobacterium nucleatum and Treponema denticola. In addition standard microbiological techniques were used for the detection of P. gingivalis, P intermedia, P. micros, A. actinomycetemcomitans. C. rectus, F. nucleatum, C. albicans and Enterobacteriaceae. Results showed a statistically significant improvement for all clinical parameters irrespective of the treatment modality. No differences were observed between test and control with regard to probing depth and attachment level. The DMDx data showed a significant reduction in both the numbers and the prevalence over the 15 months period, but no significant difference between groups. Culture data showed that at baseline two–third were positive for P. gingivalis and P intermedia. Analysis over the 18 month period showed no significant difference between the two treatment modalities. C albicans and Enterobacteriaceae were detected only in small proportions at each time interval in a limited number of patients. No adverse reactions were observed during the trial period. The present patient group responded favourably to scaling and rootplaning, but did not benefit from an effect of local of minocycline. Subgingival debridement in combination with oral hygiene instruction by itself has been shown to be effective. It remains to be studied whether local application of minocycline can be effective as an adjunct to mechanical therapy in sites that respond poorly to conventional treatment.

Notes: Abstract The purpose of the present study was to evaluate the effect of an electronic toothbrush on established plaque and gingivitis in a 5-month clinical trial. This electronic toothbrush sends approximately a 0.15 mA current through the brushhead which presumedly enhances the efficacy of the brush in plaque elimination. For this study, 80 volunteers (non-dental University students) were selected on the basis of having moderate gingival inflammation. At baseline, plaque and bleeding upon probing were assessed on the vestibular, mesio-vestibular, disto-vestibular and lingual surfaces using the “half-mouth” design. After 2-months and 5-months, these clinical indices were again recorded. At each assessment, the participants received a new brushhead. All baseline indices appeared to be well-balanced. A mean Silness and Löe plaque score of 1.70 and 1.64 were found in the control and test groups, respectively. Little change was observed from baseline to 5-months. The Quigley and Hein plaque index behaved comparably. The mean bleeding upon probing score at baseline was 1.43 and 1.39 for the control and test group, respectively. Little to no improvement was observed in the course of this study. No beneficial effect could be shown for this ‘electronic’ design of manual toothbrush.

Notes: Abstract. The purpose of the present study was to establish in vitro the inhibiting effect of a herbal extract mixture on a selected number of micro-organisms and to test in vivo the effect of a mouthwash containing 6.3 mg/ml herbal extract mixture on plaque and gingivitis as compared to a minus active control mouthrinse. The herbal extract was a mixture of: Juniperus communis (juniper), Urtica dioca (nettle), Achillaea millefolium (yarrow); 1:1:1. In the study, in-vitro, the effect of pure herbal extract mixture on acid production of Streptococcus mutans was tested and the minimum inhibitory concentrations (MIC) of the following micro-organisms were tested: Streptococcus mutans, Streptococcus mitis, Actynomyces viscosus, Actynomyces naeslundii, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Campylobacter rectus, Fusobacterium nucleatum, Veillonella parvula. The MIC-values for A. viscosus and P. gingivalis were 100 mg/ml. The MIC-values for A. naeslundii and A. actinomycetemcomitans were considerably lower (10 mg/ml). S. mitis was the most susceptible of the tested organisms to the extract with a MIC value of 1 mg/ml. S. mutans, C. rectus, V. parvula, and F. nucleatum were not influenced by the extracts. No inhibitory effect of the 6.3 mg/ml herbal extract mixture was observed on the acid production of S. mutans. For the study in-vivo, 45 volunteers were selected on the basis of having moderate gingival inflammation. As efficacy parameters the plaque index, modified gingival index and angulated bleeding index were assessed. The subjects were randomly divided among 3 experimental groups (2× test and 1‘minus active’control). The participants were requested to rinse with 10 ml of mouthwash twice a day for a period of three months. After 6 weeks and 3 months, the same clinical indices as at baseline were recorded. The results show no difference between the two test groups and the control group. In conclusion, the results of the present study have shown that the mixture of the 3 herbal extracts, Juniperus communis, Urtica dioca and Achillaea millefolium when used in a mouthrinse has no effect on plaque growth and gingival health.

Notes: Abstract The purpose of this study was to evaluate the safety and efficacy of the Braun Plak Control® for the removal of supragingival plaque and improving gingival health in a long-term clinical trial, and to compare it to a regular manual toothbrush. Assessed were plaque accumulation, amount of gingival inflammation, gingival bleeding on probing, and calculus. In total, 77 young individuals were selected on the basis of having moderate gingivitis'. They were monitored over 8 months and divided among 2 groups; a control group that used a manual toothbrush and a test group that used the Braun Plak Control. The clinical assessments were repeated after 1, 2, 5, and 8 months. At baseline, subjects were handed their assigned toothbrushes together with written oral hygiene instructions. They were instructed to brush for at least 2 min. 1 month after baseline examinations, all subjects received a professional prophylaxis and oral hygiene instruction from an experienced dental hygienist. Plaque removal was reinforced at the 2- and 5-month examination. In conclusion, results indicate that the Braun Plak Control is a safe and efficient home care device. At the end of this trial, this electric toothbrush proved to be more effective than a regular manual tooth brush.

Notes: Ionic rare gas alkali excimers Rg+A were produced by exciting Rg/A mixtures in a buffer gas atmosphere by means of an ion or electron beam. As a representative candidate the formation of Kr+K decaying at 135 nm was investigated. The rate constant k(He) for the main reaction Kr++K→Kr+K was determined varying the buffer gas density [He] between 1017 and 1020 cm−3. Values between k(He)=1×10−11 and 5×10−10 cm3 s−1 were observed. At high buffer gas densities the quantum yield ηq for the emission of the 135 nm radiation depends on the ratio [K]/[Kr]. At the optimum value, [K]/[Kr]=0.06, an absolute yield of ηq=1.5% was obtained. Up to a deposited energy of 3 mJ/cm3 the quantum yield is independent on the excitation density. For neon as buffer gas the rate constants k(Ne) are smaller by about a factor of 3, while the efficiency is only slightly less than for He. Kr+K is split into five fine structure states. The quenching of these states by krypton and buffer gas causes the low quantum yield.