Gram-positive organisms in endodontic infections

Oral Microbiology and Immunology, 2004

Journal of Clinical Microbiology, 2002

International Endodontic Journal, 2003

Chávez de Paz LE, Dahlén G, Molander A, Möller A, Bergenholtz G. Bacteria recovered from teeth with apical periodontitis after antimicrobial endodontic treatment. International Endodontic Journal, 36, 500-508, 2003. To determine whether there is a pattern for certain bacteria to remain after chemo-mechanical treatment of root canals in teeth with apical periodontitis. Consecutive root-canal samples of 200 teeth receiving root-canal treatment, referred from general practitioners and endodontic specialists for analyses of cultivable microbes, were studied prospectively. To be included, samples had to be taken at a treatment session subsequent to the one at which endodontic therapy was initiated. All samples were from teeth that either presented with clinical or radiographic evidence of apical periodontitis or both. Bacteriological findings were linked to clinical and radiographic parameters including status of the root canal prior to treatment, namely, vital pulp, necrotic pulp or root filled. A total of 248 strains were isolated from 107 teeth giving bacterial growth. Gram-positives predominated (85%). Lactobacillus spp. (22%), nonmutans streptococci (18%), and Enterococcus spp. (12%) were the most common isolates. Gram-negative anaerobes were relatively sporadic. Large radiographic bone lesions, persistent pain and use of intracanal calcium hydroxide dressing correlated with bacterial presence (P < 0.05). Once established, nonmutans streptococci, enterococci and lactobacilli appear to survive commonly following root-canal treatment of teeth with clinical and radiographical signs of apical periodontitis.

Dentistry Journal

The primary objective of endodontic therapy is to create a biologically acceptable environment within the root canal system that allows for the healing and maintenance of the health of the peri-radicular tissue. Bacteria are one of the main causes of pulp problems, and they have different methods of penetrating and invading the endodontic space such as through carious lesions, traumatic pulp exposures, and fractures. The types of bacteria found range from facultative anaerobes to aerobes, up to the most resistant species able to survive in nutrient-free environments; the bacterial species Enterococcus faecalis belongs to this last group. Enterococcus faecalis is considered one of the main causes of recurring apical periodontal lesions following endodontic treatment, with persistent lesions occurring even after re-treatment. The review presented in this paper was performed in accordance with the PRISMA protocol and covers articles from the related scientific literature that were sour...

Journal of dental research, dental clinics, dental prospects, 2009

The aim of this study was to determine the microorganisms prevalent in the necrotic dental pulp and root canals of unsuccessfully treated teeth. The present study was conducted on 150 single-rooted teeth of patients referring to a dental clinic. Sampling was performed by placing a sterile paper point in the canal for 60 s. Bacterial samples were evaluated by a microbiological technique specific for anaerobic species, used for isolation and identification of sampled strains. From the 150 samples taken, 101 were from necrotic pulps (primary infection) and 49 were from the teeth with an unsuccessful endodontic treatment (secondary infection). Enterococcus faecalis was a prevalent species in the failed root canals evaluated.

Journal of Endodontics, 2014

The aim of the present study was to analyze the microbiota of primary and secondary/ persistent endodontic infections of patients undergoing endodontic treatment with respect to clinical and radiographic findings. Methods: Samples from the root canals of 21 German patients were taken using 3 sequential sterile paper points. In the case of a root canal filling, gutta-percha was removed with sterile files, and samples were taken using sterile paper points. The samples were plated, and microorganisms were then isolated and identified morphologically by biochemical analysis and sequencing the 16S rRNA genes of isolated microorganisms. Results: In 12 of 21 root canals, 33 different species could be isolated. Six (50%) of the cases with isolated microorganisms were primary, and 6 (50%) cases were endodontic infections associated with root-filled teeth. Twelve of the isolated species were facultative anaerobic and 21 obligate anaerobic. Monomicrobial infections were found for Enterococcus faecalis and Actinomyces viscosus. E. faecalis was most frequently isolated in secondary endodontic infections (33%). Moraxella osloensis was isolated from a secondary endodontic infection that had an insufficient root canal filling accompanied by a mild sensation of pain. A new bacterial composition compromising Atopobium rimae, Anaerococcus prevotii, Pseudoramibacter alactolyticus, Dialister invisus, and Fusobacterium nucleatum was recovered from teeth with chronic apical abscesses. Conclusions: New bacterial combinations were found and correlated to clinical and radiographic findings, particularly to chronic apical abscesses. M. osloensis was detected in root canals for the second time and only in German patients. (J Endod 2014;40:670-677)

Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2006

Objective. The objective of this study was to investigate the presence of Enterococcus faecalis in endodontic infections by culture and polymerase chain reaction analyses. Study design. Microbial samples were obtained from 50 teeth with untreated necrotic pulps (primary infection) and from 50 teeth with failing endodontic treatment (secondary infection). Culture techniques were used including serial dilution, plating, incubation, and biochemical identification. For PCR detection, samples were analyzed using a species-specific primer of the 16S rDNA and the downstream intergenic spacer region. Results. Culture and PCR detected the test species in 23 of 100 and 79 of 100 of the teeth, respectively. E faecalis was cultured from 2 (4%) of 50 necrotic canals and from 21 (42%) of 50 root-treated canals. PCR detection identified the target species in 41 (82%) and 38 (76%) of 50 primary and secondary infections respectively. Conclusion. E faecalis was detected as frequently in teeth with necrotic pulp as in teeth with failing endodontic treatment when a PCR analysis was used.

Biotechnology and …, 2006

Objective: The purpose of this study is to investigate the type of microorganisms isolated from necrotic pulp tissues and from failed endodontic treatments in infected root canals. Methods: This study is based on an experiment conducted on 90 patients between November, 2002 and November, 2003 using a sampling. One hundred single root canals were microbiologically sampled from these patients by using sterile paper points. Among 100 canals sampled, 61 had primary infection and 39 had a history of secondary infection. Microorganisms were isolated and identified by using established advanced microbiologic techniques for anaerobic species. Results: A total of 197 cultivable isolates were recovered, the microbial findings in both types of canals, such as the number of species isolated, the 68.0% of Gram-positives and 27.9% gram-negatives, the 52.8% of facultative and 43.1 % strict anaerobic microorganisms 4.1% fungi and so on. Ten canals presented no microbial growth. Conclusions: The prevalence of bacteria and fungi found in 100 root canals is the prevalence of the microbial genera in primary and secondary endodontic infection. Peptostreptococcus spp was the most predominantly isolated microbial genera,

Stomatoloski glasnik Srbije, 2010

Introduction. Bacteria from the root canal can penetrate beyond the apex and cause acute or chronic inflammation in periapical region. The aim of this study was to investigate the prevalence of different forms of apical periodontitis and to determine the presence of Gram-negative anaerobic bacteria in samples taken from the root canal and oral cavity. Materials and Methods. Study included 45 patients, 30 adults and 15 children. Three samples from the root canal and one from the oral cavity from the patients with apical periodontal inflammation were taken and grown on Schaedler agar enriched with 5% sheep blood, Schaedler agar enriched with 5% sheep blood and 20% bile, Schaedler agar enriched with 5 % sheep blood supplemented with 7.5 mg/L vancomycin and thyoglycolate broth (Biomerieux?). Final identification of bacteria was carried out by the API A system (Biomerieux?). Results. Based on clinical history and radiographic findings chronic granulomatous apical periodontitis was diagno...

Since 1890, when Miller first observed microorganisms associated with pulp tissue, microorganisms have been implicated in infections of endodontic origin. Microbes seeking to establish in the root canal must leave the nutritionally rich and diverse environment of the oral cavity, breach enamel, invade dentine, overwhelm the immune response of the pulp and settle in the remaining necrotic tissue within the root canal. During that time they have to compete in a limited space with other microbes for the available nutrition. It is no accident that microbes berth in a particular environment there are ecological advantages for them to establish and flourish if conditions are favorable. This review will highlight the recent facts and controversies related to endodontics microbiology.