Clinical Responses to Mechanical Periodontal Treatment in Chinese Chronic Periodontitis Patients with and withoutActinobacillus actinomycetemcomitans

Persistence of Porphyromonas gingivalis is a negative predictor in patients with moderate to severe periodontitis after nonsurgical periodontal therapy

OBJECTIVES

The aim of this study was to evaluate the quality of prediction for stable results after nonsurgical periodontal therapy by several microbiological variables of the subgingival biofilm and biomarkers of gingival crevicular fluid or oral lavage.

MATERIAL AND METHODS

Forty-six individuals with moderate or severe chronic periodontitis receiving nonsurgical periodontal therapy were monitored for clinical variables, selected microorganisms, and biomarkers at baseline and 3 and 6 months thereafter. Logistic regression analysis and general linear model (GLM) were applied for analysis of variance and covariance.

RESULTS

At 6 months, 20 patients showed a high response (HR) to treatment (at least 60 % of reduction of numbers of sites with PD >4 mm), whereas 26 did not (low response, LR). All clinical variables were significantly improved at 3 and 6 months within each group (p < 0.001, each compared with baseline). Modeling the impact of Porphyromonas gingivalis, Treponema denticola, and median of MMP-8 on to the response to treatment as continuous variables by GLM showed a significant influence of these variables (p = 0.045) with the strongest influence of P. gingivalis (p = 0.012) followed by T. denticola (p = 0.045) and no association with MMP-8 (p = 0.982). Samples tested positively for P. gingivalis decreased only in HR (3 months: p = 0.003; 6 months: p = 0.002). Calprotectin levels in GCF were lower in the HR group compared with the LR group at 3 months (p = 0.008) and at 6 months (p = 0.018).

CONCLUSION

Persistence of P. gingivalis combined with a high GCF level of calprotectin may have a negative predictive value on response to periodontal therapy.

CLINICAL RELEVANCE

Microbiological diagnostics for P. gingivalis before and 3 months after SRP may have a predictive value on response to periodontal therapy. The combination with MMP-8 in oral lavage or preferably calprotectin in GCF might give additional information.

Local Oxygen Therapy for Treating Acute Necrotizing Periodontal Disease in Smokers

BACKGROUND

The main aim of treatment for acute necrotizing periodontal disease is fast and effective reduction of anaerobic destructive microorganisms to avoid periodontal damage. The effect of adjunctive local oxygen therapy in the treatment of necrotizing periodontal disease was examined in this study.

METHODS

Thirty patients with acute necrotizing periodontal disease were treated with the systemic antibiotics amoxicillin, clavulanic acid, and metronidazole. In 15 out of 30 patients, adjunctive local oxygen therapy was administered. The patients were followed from the first to 10th day of treatment with clinical and bacteriological examinations. The clinical examination registered gingival bleeding, periodontal probing depth, and attachment loss; to follow up microbiological colonization of the periodontal sulcus, five representative bacteria were registered by a semiquantitative DNA polymerase chain reaction test.

RESULTS

In both groups of patients, colonization with Prevotella intermedia, Tannerella forsythensis, and Treponema denticola was initially positive. None of these three microorganisms were completely eradicated in any of the patients in the group without oxygen therapy within the first 10 days of treatment. In the group with adjunctive oxygen therapy, all patients either showed a reduction in or complete eradication of the microorganisms, resulting in more rapid clinical restitution with less periodontal destruction.

CONCLUSIONS

Adjunctive oxygen therapy results in early eradication of pathogenic anaerobic microorganisms in cases of acute necrotizing periodontal disease. The damage to periodontal tissue is reduced.

Characterization of Actinobacillus actinomycetemcomitans isolated from young Chinese aggressive periodontitis patients

OBJECTIVE

This study characterized Actinobacillus actinomycetemcomitans isolates from young Chinese aggressive periodontitis patients.

METHODS

Subgingival plaque samples (two/subject) were collected from diseased subjects < 25 years old (n = 9, mean age 21.1 +/- 1.6 years) and age-matched periodontitis-free controls (n = 47, mean age 22.0 +/- 1.1 years). Selective and anaerobic culture were used. The serotype, leukotoxin gene (ltx) operon promoter and the cytolethal distending toxin (cdt) genes complex of the A. actinomycetemcomitans isolates were investigated. Effects of the isolates on non-keratinizing periodontal ligament epithelial cells monolayer were studied.

RESULTS

Diseased subjects had significantly higher full-mouth bleeding score (p = 0.002) and total viable counts from plaque samples (7.2 x 10(6) vs. 2.1 x 10(5) CFU/paperpoint, p < 0.005). A. actinomycetemcomitans was isolated from 67%/56% or 6%/4% of diseased or controls subject/sites, respectively (p < 0.001). The proportion of A. actinomycetemcomitans isolatable from aggressive periodontitis or periodontitis-free associated subgingival plaque was low (0.7% vs. 0.1%, p < 0.02). The serotype of the isolates was characterized. All isolates possessed 652-like ltx gene promoter and all but one serotype c isolate from a diseased patient had intact cdtABC genes. That particular strain appeared to confer the least cellular damages on periodontal ligament epithelial monolayer compared to others.

CONCLUSION

This preliminary study confirmed the notion of increased prevalence and quantity of A. actinomycetemcomitans associated with aggressive periodontitis in young patients. The overall ltx promoter and cdt characteristics of the A. actinomycetemcomitans isolates, however, were similar among the diseased and control groups. A strain lacking the cdtABC gene appeared to be less damaging to a periodontal ligament epithelial cell model. Further studies therefore are warranted to clarify the pathogenic role and potentials of A. actinomycetemcomitans in aggressive periodontitis.