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Updated: Jul 13, 2026

Robust Ligature-Induced Model of Murine Periodontitis for the Evaluation of Oral Neutrophils
Published on: January 21, 2020
Periodontal pathogens in erupting third molars of periodontally healthy subjects
A Rajasuo1, O J Sihvonen, M Peltola
1Department of Oral and Maxillofacial Diseases, Mikkeli Central Hospital, Mikkeli, Finland. ari.rajasuo@esshp.fi
Abstract:
The presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Tannerella forsythensis in bacteriologic samples of 5-7-mm deep mandibular third-molar pericoronal pockets was analysed by polymerase chain reaction, to test the hypothesis that these sites would harbour the bacteria. The patients were periodontally healthy 20-year-old Finnish male conscripts. Sixteen had acute pericoronitis, 28 chronic pericoronitis, and 15 were symptom-free controls. A. actinomycetemcomitans was detected in only 7% of the samples from chronic pericoronitis cases, whereas P. gingivalis was positive in 20% of the symptom-free versus 69% (P = 0.018) of the acute and 57% (P = 0.044) of the chronic cases. The percentages for P. intermedia were 93, 94 and 93%, and for T. forsythensis 47, 63 and 57%, respectively. These results confirm that, apart from A. actinomycetemcomitans, periodontopathogens are common in third-molar sites in periodontally healthy individuals.
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