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A 15-year-old girl developed perioral dermatitis and swelling of the lips, having played a flute made of cocus wood for 2 years. Patch tests with wood shavings, as well as with subsequently isolated constituents named Cocus I and Cocus II, were strongly positive. After complete purification, both contact allergens were identified as isoflavan derivatives. While Cocus I was shown to be 7, 8-dihydroxy-2', 4', 5'-trimethoxyisoflavan, the structure of Cocus II could not be elucidated exactly. It could have been either 7, 8, 3'-trihydroxy-2', 4'-dimethoxyisoflavan or 7, 8, 2'-trihydroxy-3', 4'-dimethoxyflavan. The exact position of the hydroxy and methoxy group in C-2' and C-3' can be determined only by complete synthesis of both compounds or by isolation of greater amounts of Cocus II for further oxidation experiments. Due to the stronger patch test reaction and the higher yield of Cocus I in the wood, this hydroxyisoflavan must be recognized as the main contact allergen. [ABSTRACT FROM AUTHOR]

Australian Blackwood is known to be an important cause of allergic contact dermatitis in Australia. Previous investigations have shown that 2,6-dimethoxy-1,4-benzoquinone and acamelin are 2 of the responsible, but weak, sensitizers. When these 2 quinones are lacking, which is occasionally found, the wood still possesses allergenic properties. The present re-examination led to the isolation and identification of 4 hydroxyflavans, of which 3 proved to be allergens. Melacacidin, known to be the main constituent of these flavan derivatives in the heartwood, was isolated and its sensitizing capacity in guinea pigs determined. It showed a moderate sensitizing power. Melacacidin occurs abundantly in 125 Australian and 3 African Acacia species. [ABSTRACT FROM AUTHOR]

Experimental and chemical investigations revealed that common ivy (Hedera helix susp. helix) contains 3 compounds which are powerful irritants and moderate sensitizers. Only 2 of these constituents, falcarinol and didehydrofalcarinol, are present in the plant during the whole year. Besides Panax ginseng and Srchfflera arboricala, this is the third species of the Araliaceae in which these polyacetylenic sensitizers have been found. Falcarinol and didehydrofalcarinol also occur in Hedera helix subsp canariensis, 4 patients have been patch tested. Even in low concentrations (0.03%). the main allergin falcarinol elicited strong reactions in all of them. One of the authors became sensitized during the investigations. [ABSTRACT FROM AUTHOR]

A variety of parameters is available to assess the efficacy of oral antiseptics. Most study protocols select the parameters according to the specific study goal or according to preferences of the researchers. Beside general recommendations for home-use studies, no recommendations exist for other study types. Therefore, pre-selected parameters should be compared within several study designs and the most suitable parameters should be recommended for further application. The following parameters were selected before study start: plaque indices (PlI, Silness & Loe 1964, M-QHI, Turesky et al. 1970), plaque area (PlA), bacterial vitality (BV, Netuschil et al. 1989), gingivitis indices (GI, Loe 1967; M-GI, Lobene et al. 1986; BOP, Ainamo & Bay 1975), gingival crevicular fluid, colony forming units, and the discoloration index (DI, Brecx et al. 1993). The parameters were applied in four study designs: eight-hour substantivity studies, four-day plaque re-growth studies, 21-day experimental gingivitis studies, and six-month home-use studies. Pearson correlation coefficients were computed. The highest correlations were found between PlI and M-QHI and between GI and M-GI (p<0.01) in all corresponding studies and treatment groups. Few middle correlations existed between BOP and the other gingival indices. Neither GI nor M-GI correlated with GCF nor did BV with plaque indices. Inconsistent correlations were obtained between PlA and plaque indices and between PlI and GI. It is concluded, that primary parameters for these designs should be one plaque index and/or one gingivitis index to monitor plaque and gingivitis. The other parameters did not yield additional information about the study outcome.

In the literature and in the daily study routine, a wide range of study designs exists to test the efficacy of mouthrinses. Within these various designs, a considerable number of parameters is applied. Due to the different protocols currently used the outcome of these investigations is hardly to compare. Therefore, it was the aim of the present investigation to assess suitable study designs of different durations, to select and compare parameters, and to find suitable study participants in order to finally recommend more standardized protocols for future studies on oral antiseptics. Eight-hour substantivity studies, four-day plaque re-growth studies, 21-day experimental gingivitis studies, and six-month home-use studies were performed either cross-over or parallel. The clinical studies were randomized, controlled, and investigator-blinded. From most often applied clinical and laboratory parameters, two plaque indices, bacterial vitality, three gingivitis indices, gingival crevicular fluid, colony forming units, and the discoloration index were selected to assess plaque inhibition, gingivitis development, tooth staining, and possible bacterial shifts in the oral cavity. Four or five, respectively, treatment groups were formed that rinsed with the following solutions: chlorhexidine digluconate 0.06%, 0.12%, 0.20%, amine fluoride/stannous fluoride, and a negative control. In addition, all study designs were tested on two different study populations. Population alpha consisted of persons who had a gingival index <0.8 while population beta participants presented a mean gingival index of >/=0.8. Pearson correlation coefficients were calculated between parameters and between subsets of teeth and full-mouth recording. T-tests were applied to compare between populations alpha and beta.

Gingival recessions in the upper jaw were covered by a modified bridging flap and follow-up examinations were carried out over three years. After one year the covering result was 72% and after three years 66%.