The effect of female sex hormones on subgingival plaque

The origin of periodontal infections

Periodontal diseases are recognized as bacterial infections, and some forms are associated with specific organisms, such as Actinobacillus actinomycetemcomitans in juvenile periodontitis, and Bacteroides gingivalis and others in adult periodontitis. The source of the periodontal organisms, whether they are part of the indigenous or resident flora and overgrow to become opportunistic oral pathogens, or whether they are exogenous oral pathogens, is important to determine. The chain of periodontal infection, microbial agent(s) and their transmission, and host response are reviewed with respect to the role of A. actinomycetemcomitans in localized juvenile periodontitis and B. gingivalis in adult periodontitis. The present data lead us to hypothesize that some periodontal organisms may be exogenous pathogens.

Prevention of periodontal diseases may be influenced by the knowledge of whether various forms are caused by opportunistic organisms or exogenous pathogens. If exogenous pathogens are responsible, prevention can be directed to intercepting transmission, thereby preventing colonization. On the other hand, if the organisms are opportunistic pathogens, prevention might be directed at interfering with initial acquisition of the flora earlier in life, as well as suppressing them to low levels consistent with health. For those exogenous periodontal infections, attempts at eradication and prevention of re-infection are likely to be effective. If the organisms are part of the indigenous flora, there is little hope of complete elimination of the organism.

Criteria for distinguishing exogenous periodontal pathogens from opportunistic periodontal pathogens include the prediction that exogenous pathogens would be transient members of the oral flora associated with periodontal disease, likely to be comprised of one or a few clonal types, and intrinsically virulent. In contrast, opportunistic periodontal pathogens would likely be members of the indigenous flora and would overgrow. They would likely be comprised of many clonal types, and have an intrinsically low level of virulence.

Relationships between periodontal health, salivary steroids, and Bacteroides intermedius in males, pregnant and non-pregnant women

Relationships between four steroids, determined by radio-immunoassay of whole saliva, and clinical and bacteriological parameters were studied in 90 subjects: males, menstruating females, and pregnant females. Pocket depths and both plaque and gingival bleeding scores were recorded. Total counts and percentages of Gram-negative organisms Bacteroides and B. intermedius were determined from anaerobic cultures of subgingival plaque from 9-14 subjects in each group. None of the clinical parameters for the pregnant females differed significantly from those of non-pregnant females, nor did these parameters show any significant correlation with progression of pregnancy. No correlations were detected between bacterial and clinical parameters in the pregnant group. There were no statistically significant differences between the total bacterial counts from the three groups, yet males had significantly higher proportions of Gram-negative bacteria, Bacteroides, and B. intermedius, than did pregnant and non-pregnant females. Proportions of B. intermedius did not differ significantly between the two female groups, nor was there any correlation with progression of pregnancy. While some steroids appeared to affect some clinical or bacteriological parameters in some groups, no obvious patterns consistent with different steroid levels were detected. The results do not indicate that increased hormone levels cause more severe periodontal disease in pregnant women, nor that high salivary steroid levels result in increased recovery of B. intermedius from subgingival plaque.

Relationship between lactate dehydrogenase and myeloperoxidase levels in human gingival crevicular fluid and clinical and microbial measurements

The present study was designed to determine, in a cross-sectional study, whether there was any relationship between levels of lactate dehydrogenase (LDH) and myeloperoxidase (MPO) in gingival crevicular fluid (GCF) and clinical periodontal status or microbial parameters. Another objective was to determine, in a longitudinal study, the effect of a single session of root planning on GCF levels of LDH and MPO and the relation to changes in clinical and microbial measurements. 15 and 12 test subjects with moderate to severe periodontal disease were seen in the cross-sectional and longitudinal study, respectively. 1 healthy and 2 diseased sites were evaluated in each subject. Higher LDH and MPO levels in GCF were closely associated with higher clinical and microbial signs of periodontal disease. Root planing was effective in reducing these enzymes in GCF, with an accompanying decrease in clinical and microbial signs associated with disease. The return of LDH to baseline levels at 3 months after instrumentation, without a corresponding return of clinical signs of disease, may serve as a marker for subclinical periodontal pathology.

Differences in periodontal disease-associated microorganisms of subgingival plaque in prepubertal, pubertal and postpubertal children

It is generally accepted that normal prepubertal children do not develop periodontitis, and that the severity of gingivitis in prepubertal children is usually less than that observed in children after puberty. One possible explanation is that the bacteria associated with periodontal diseases cannot become established in great numbers prior to puberty. Studies by Kornman and Loesche and others suggest that levels of black pigmented Bacteroides, especially B. intermedius, increase with increased levels of gonadotrophic hormones in pregnant women. Delaney and Kornman have found that there is a similar increase in levels of black pigmented Bacteroides with puberty. The present study involved cultural and microscopic characterization of the subgingival plaque flora of prepubertal, circumpubertal and postpubertal children with similar Silness and Löe plaque index scores. Puberty was confirmed through examination of wrist radiographs. Populations of black pigmented Bacteroides were very low in prepubescent children and were much higher in circumpubertal and postpubertal children. However, B. intermedius predominated only in circumpubertal plaques. Levels of total motile bacteria increased at each age level, but levels of spirochetes above 2% were observed only in the postpubertal group. These results support those of previous investigators who postulated a relationship between hormone levels and black pigmented Bacteroides levels in subgingival plaque and suggest that differences in the subgingival environment profoundly influence the proportions of suspected periodontopathic species in plaque.

Puberty gingivitis in insulin-dependent diabetic children. I. Cross-sectional observations

This cross-sectional study examined the gingivitis occurring at puberty in a population of insulin-dependent juvenile diabetics. Seventy-seven children between the ages of 6 and 15 years were examined for gingivitis levels, stages of pubertal maturation and blood levels of glucose and glycosylated hemoglobin. Bacterial plaque was sampled from one or more approximal tooth surfaces of every subject and cultured under anaerobic and aerobic conditions on nonselective and selective media. The total cultivable flora and percentage of certain presumptive periodontopathic bacteria were determined. Before puberty, children with "high" levels of glycosylated hemoglobin also had higher gingivitis levels than children with "normal" metabolic control of diabetes. During puberty, the level of gingivitis increased independently from both fasting blood glucose levels and per cent glycosylated hemoglobin. The microbiota of marginal plaque was predominantly composed of facultatively anaerobic bacteria. The percentages of Capnocytophaga sp and Actinomyces naeslundii were statistically higher at the onset of puberty, suggesting that a specific bacterial shift in the microbial composition of marginal plaque occurs in response to host changes in juvenile diabetic children at this age period.