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Updated: Aug 13, 2026
11:15
In Situ Detection of Bacteria within Paraffin-embedded Tissues Using a Digoxin-labeled DNA Probe Targeting 16S rRNA
Published on: May 21, 2015
Epithelium and bacteria in periapical lesions
Domenico Ricucci1, Elizeu A Pascon, Thomas R Pitt Ford
1dricucci@libero.it
Summary
Bacteria were present in all periapical lesions studied, primarily in abscesses or cysts. Granulomas were the most common lesion type, while cysts were frequently epithelialized.
Area of Science:
- Dentistry
- Oral Pathology
- Microbiology
Background:
- Periapical lesions are common in endodontic and oral surgery practices.
- Understanding the microbial and epithelial components of these lesions is crucial for diagnosis and treatment.
Purpose of the Study:
- To investigate the presence and distribution of bacteria and epithelium in 50 human periapical lesions.
- To classify the types of periapical lesions and correlate findings with clinical presentation.
Main Methods:
- Histological examination of serial sections from 50 extracted human teeth with periapical lesions.
- Identification and characterization of bacterial presence and epithelial lining within the lesions.
Main Results:
- Bacteria were universally found, colonizing necrotic tissue and present in the periapical lesions of 18 abscesses or cysts.
- Epithelium was observed in 21 lesions; granulomas (20) were the most frequent type, followed by cysts (16) and abscesses (14).
- Apical ramifications were more common (37 cases) than single foramina (13 cases), and inflamed tissue was found in the apical root canal in one-third of cases.
Conclusions:
- Granulomas represent the most prevalent periapical lesion type.
- Epithelialized lesions were predominantly cysts.
- Periapical bacteria were specifically associated with abscesses and cysts, not granulomas.
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