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Published on: December 17, 2015
[Study of association between Parvimonas micra and pulp dominant pathogens in the infected root canals with chronic
1Department of Cariology and Endodontology, Capital Medical University School of Stomatology, Beijing 100050, China.
Objective:
To study the prevalence of Parvimonas micra (Pm) and the associations between Pm and pulp dominant pathogens in order to reflect the colonization of Pm in the infected root canals with chronic periradicular periodontitis.
Methods:
A total of 120 teeth diagnosed as chronic periradicular periodontitis from 104 patients were included into the study. The teeth were allocated into untreated (primary infectious) and root-canal- treated (secondary infectious) groups with 60 in either group. Samples were collected from the root canals using sterile files and paper points, and subsequent extraction of bacterial DNA was undertaken. The Pm 16S rDNA level was evaluated using 16S rDNA PCR. The prevalence of Pm in chronic periradicular periodontitis was determined accordingly. Then, the associations of Pm and Enterococcus faecalis (Ef), Porphyromonas endodontalis (Pe) as well as Porphyromonas gingivalis (Pg) were analysed.
Results:
Pm was detected in 40% (24/60) of the samples from the primary infectious group, 5% (3/60) from the secondary infectious group. The prevalences of Pm from the two groups were different significantly (χ² = 21.06, P < 0.05). Significant correlations (untreated group OR = 5.98, root-canal-treated group OR = 33.50) between Pm and Pe were identified in both groups, while the correlations between Pm and Pg as well as Ef were not of significance, respectively.
Conclusions:
A significantly higher relevance ratio of Pm was estimated in the primary infectious group than the secondary infectious one. Pm and Pe were correlated significantly in the infected root canals, suggesting a symbiotic relation between these two bacteria.
Insights
Parvimonas micra (Pm) is more prevalent in untreated root canals. This study found a significant association between Pm and Porphyromonas endodontalis (Pe), suggesting a symbiotic relationship in chronic periradicular periodontitis.
Area of Science:
- Microbiology
- Endodontics
- Periodontology
Background:
- Chronic periradicular periodontitis involves complex microbial communities.
- Understanding the role of specific bacteria like Parvimonas micra (Pm) is crucial for effective treatment.
Purpose of the Study:
- To determine the prevalence of Pm in infected root canals.
- To investigate the association between Pm and key pulp pathogens: Enterococcus faecalis (Ef), Porphyromonas endodontalis (Pe), and Porphyromonas gingivalis (Pg).
Main Methods:
- 120 teeth with chronic periradicular periodontitis were analyzed.
- Samples were categorized into untreated (primary) and root-canal-treated (secondary) infectious groups.
- 16S rDNA PCR was used to quantify Pm, and associations with other bacteria were statistically analyzed.
Main Results:
- Pm was detected in 40% of primary infectious samples versus 5% in secondary infectious samples.
- A significant correlation was found between Pm and Pe in both untreated (OR = 5.98) and treated (OR = 33.50) groups.
- No significant correlations were observed between Pm and Pg or Ef.
Conclusions:
- Pm shows a higher prevalence in primary root canal infections compared to secondary ones.
- The significant correlation between Pm and Pe suggests a potential symbiotic relationship in infected root canals.
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