[Comparison of subgingival plaque buccally and interdentally localized during 3-week experimental gingivitis in humans]. / Vergleich subgingivaler Plaque an bukkalen und interdentalen Lokalisationen während einer dreiwöchigen experimentellen Gingivitis beim Menschen.

During 21 days of abolished oral hygiene and developing gingivitis the microbial changes were studied in buccal and interdental sites. The subgingival plaque of 6 dental students was analyzed by darkfield microscopy. The microbiota found in interdental sulci showed a higher complexity than that of buccal sites. Buccally and interdentally there was a significant increase in the total number of microorganisms between days 0 and 21. Yet, the development of gingivitis was slower in the buccal than in the interproximal sites. For all bacteria, but specially for more disease-associated morphotypes the accumulation rate was higher interdentally than buccally.

[Microbiological findings of subgingival plaque during long-term experimental gingivitis in humans]. / Mikrobiologische Befunde in subgingivaler Plaque während einer experimentellen Langzeitgingivitis beim Menschen.

During six month of abolished oral hygiene and concomitant development of gingivitis, the buccal subgingival microbiota was studied by darkfield microscopy as well as by cultural methods. Five dental students gave written informed consent and participated in this trial. In darkfield microscopy there was a slow reduction in the proportion of coccoid forms concomitant with an increase in the proportion of rods, while spirochetes were rarely detected during the entire experimental period. However, the cultural data revealed a decrease of the Gram-positive facultative and an increase of the Gram-negative anaerobic microorganisms after 6 months of abolished oral hygiene. The bacteriological data show, that in buccal sites--even after 6 months of abolished oral hygiene--the subgingival microflora reflects a population typical only for an initial lesion.

Gingival health and gingivitis development during puberty. A 4-year longitudinal study.

The purpose of this investigation was to follow the development of the gingival conditions during puberty and to correlate oral clinical parameters with chronological age as well as with parameters used for the determination of the pubertal development. In 22 boys and 20 girls pubertal and skeletal development, as well as plaque index (PlI) and gingival index (GI) were monitored at 1-year intervals between the ages of 11 and 15 years. During this time, the papillary bleeding index (PBI) was assessed 10 times in all interdental spaces of the dentition. The bleeding tendency, represented by whole mouth mean PBI values, as well as the % of bleeding interdental sites, was found to increase significantly with the start of the pubertal phase. It reached a peak value after 1-5 years in 35% of the children. A significant trend of decrease was noted after the age of 14 years in boys and girls. In boys, mean PBI and the % of interdental sites with bleeding were correlated with testes growth, in girls with the Tanner index for secondary sex characteristics (breast development). PlI and GI, which were only recorded annually, did not show a significant trend of increase or decrease.

Microbial and clinical measurements of periodontal pockets during sequential periods of non-treatment, mechanical debridement and metronidazole therapy.

Microbial and clinical parameters were studied in 11 subjects with chronic inflammatory periodontitis. 2 periodontal pockets per subject were studied longitudinally. The microbial parameters included counts of different subgingival micro-organisms by dark field microscopy, counts of the total colony forming units (c.f.u.) on anaerobic blood agar, the facultative anaerobic counts and counts of black-pigmented Bacteroides, Fusobacterium and E. corrodens. The clinical parameters were probing pocket depth, bleeding after probing and crevicular fluid production. Clinical and microbial observations were compared during 3 consecutive periods of non-treatment, debridement and metronidazole therapy. The experimental sites were debrided by deep scaling while no debridement was carried out at the control sites. The effect of this treatment was studied over a period of 3 months. Then, at the experimental sites, a 2nd session of debridement was followed by administration of metronidazole. The effect of metronidazole alone and combined with mechanical debridement was studied during a subsequent 3-month period. The disease activity did not correlate with the microbial parameters and was evident in the presence as well as in the absence of black-pigmented Bacteroides. A single session of subgingival debridement resulted in significant reductions in probing depth, spirochetes, motile organisms, black-pigmented Bacteroides and E. corrodens. Repopulation of the subgingival sites was observed. However, the composition of the subgingival microbiota remained significantly changed during the 3 months after debridement. The re-isolation of the same Bacteroides-species and the same B. gingivalis type after treatment indicated an outgrowth of micro-organisms remaining at these sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Metronidazole concentrations in human plasma, saliva, and gingival crevice fluid after a single dose.

Metronidazole concentrations were estimated in four human volunteers after a single dose of 750 mg taken orally. Samples of blood, saliva, and gingival crevice fluid were collected before intake and during the following 24 hours. The concentrations of metronidazole in plasma and saliva were measured by high-performance liquid chromatography (HPLC). The concentrations in gingival fluid were estimated by a capillary agar-diffusion assay. The results of the metronidazole measurements as obtained by both methods were significantly correlated. The peak concentrations of metronidazole in plasma and saliva were in the same range, 8.7-13.8 micrograms/mL, and similar concentrations were found in the gingival fluid samples. It is concluded that metronidazole taken orally has similar pharmacokinetics in both saliva and plasma, and that a single oral dose of 750 mg metronidazole leads to a concentration of the drug in the gingival crevice fluid that exceeds the minimal inhibitory concentration for most anaerobic oral micro-organisms.

The effect of amoxicillin on destructive periodontitis. A case report.

In a 22-year-old female patient, advanced localized periodontal destruction was observed. The planned treatment consisted of oral hygiene instructions, professional plaque control, deep scaling and root planning and finally modified Widman flap surgery. One molar had to be extracted but was left untreated initially as a control. During the treatment period of 9 months and during 1 year thereafter, samples were taken of the subgingival plaque for dark-field microscopy. The unplanned use of amoxicillin by the patient for a middle ear infection resulted in a suppression below detection level of spirochetes at the investigated sites. At the nontreated control site, the absence of spirochetes was accompanied by a 3-mm reduction of pocket depth and a 2-mm gain in clinical probing attachment, while some formation of new alveolar bone was observed. At the treated sites, clinical improvement was observed. However, a distinction between the effect of the periodontal therapy and the nonscheduled use of amoxicillin could not be made at the treated sites. It is concluded that a single course of systematically administered amoxicillin changed the composition of the subgingival microflora over a long period of time (17 months) and had a beneficial effect upon the status of the periodontium.