Streptococcus gwangjuense sp. nov., Isolated from Human Pericoronitis.

A novel facultative anaerobic, Gram-stain-negative coccus, designated strain ChDC B345T, was isolated from human pericoronitis lesion and was characterized by polyphasic taxonomic analysis. The 16S ribosomal RNA gene (16S rDNA) sequence revealed that the strain belonged to the genus Streptococcus. The 16S rDNA sequence of strain ChDC B345T was most closely related to those of  Streptococcus mitis NCTC 12261T (99.5%) and Streptococcus pseudopneumoniae ATCC BAA-960T (99.5%). Complete genome of strain ChDC B345T was 1,972,471 bp in length and the G + C content was 40.2 mol%. Average nucleotide identity values between strain ChDC B345T and S. pseudopneumoniae ATCC BAA-960T or S. mitis NCTC 12261T were 92.17% and 93.63%, respectively. Genome-to-genome distance values between strain ChDC B345T and S. pseudopneumoniae ATCC BAA-960T or S. mitis NCTC 12261T were 47.8% (45.2-50.4%) and 53.0% (51.0-56.4%), respectively. Based on these results, strain ChDC B345T (= KCOM 1679T = JCM 33299T) should be classified as a novel species of genus Streptococcus, for which we propose the name Streptococcus gwangjuense sp. nov.

Application of Denaturing Gradient Gel Electrophoresis to the Analysis of Bacterial Communities Associated With Asymptomatic and Symptomatic Pericoronitis.

PURPOSE: Denaturing gradient gel electrophoresis (DGGE) was used to investigate the bacterial communities associated with asymptomatic and symptomatic pericoronitis. The aim of the study was to compare the fingerprinting patterns of these 2 clinical conditions. MATERIALS AND METHODS: The microbiota of mandibular third molar pockets associated with asymptomatic or symptomatic pericoronitis cases were collected and profiled by the polymerase chain reaction DGGE method. Banding patterns were compared by cluster analysis techniques. RESULTS: Thirteen symptomatic pericoronitis and 7 asymptomatic pericoronitis samples were collected. Comparative analysis of the 2 clinical conditions showed bands that were common to the symptomatic and asymptomatic cases, but most DGGE bands appeared to be unique to the clinical condition. No single band occurred in all profiles. The mean number of bands detected in the 16S rDNA community profiles was 23.8 ± 4.2 (range, 19 to 34) for samples from symptomatic cases and 24.1 ± 2.4 (range, 21 to 29) for those from asymptomatic cases. Cluster analysis and multidimensional scaling analysis of the DGGE banding pattern showed a distinction in the similarity of banding patterns according to the presence or absence of symptoms. CONCLUSIONS: These results suggest that the diversity of pericoronal pocket microbiota in asymptomatic pericoronitis cases differs markedly from that of symptomatic cases.

Herpesviral-bacterial co-infection in mandibular third molar pericoronitis.

OBJECTIVE: The aim of this study was to assess the presence of herpesviruses and periodontopathic bacteria and to establish their potential association with pericoronitis. MATERIALS AND METHODS: Fifty samples obtained with paper points (30 from pericoronitis and 20 controls) were subjected to polymerase chain reaction (PCR) analysis. A single-stage and nested PCR assays were used to detect herpesviruses: human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) and six periodontopathic anaerobic bacteria: Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Parvimonas micra, Treponema denticola, and Tannarella forsythia. RESULTS: Pericoronitis samples harbored HCMV and EBV at significantly higher rates than the control group (70 vs. 40 % and 46.7 vs. 15 %, P = 0.035, P = 0.021, respectively). P. micra and T. forsythia (66.7 vs. 0 %, and 40 vs. 10 %, P = 0.001, P = 0.021, respectively) were significantly more common in pericoronitis compared to the control group. Multivariate logistic regression analysis showed that the presence of T. forsythia was associated with pericoronitis development (OR 7.3, 95 % CI, 1.2-43.2, P = 0.028). CONCLUSION: The occurrence of HCVM and EBV extends our previous knowledge on microbiota in pericoronitis. These PCR-based findings demonstrated that bacterial and viral DNA occurred concomitantly in pericoronitis samples. T. forsythia appeared to be significantly associated with pericoronitis development in the examined sample. CLINICAL RELEVANCE: Herpesviral-bacterial co-infections might exacerbate the progression of pericoronitis.

Evaluation of periodontal pathogens of the mandibular third molar pericoronitis by using real time PCR.

OBJECTIVES: The aim of this study was to investigate the mandibular third molar pericoronitis flora by using real-time polymerase chain reaction (PCR). MATERIALS AND METHODS: The quantitative values of Aggregatibacter actinomycetemcomitans (Aa), Campylobacter rectus (Cr), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi) and Tannerella forsythia (Tf) were evaluated in comparison with the healthy third molar flora by using real time PCR. RESULTS: Aa, Cr, Pg, and Pi were not statistically significant but numerically higher than the pericoronitis group. In contrast to samples from control subjects, statistically significant higher numbers of Tf were detected in samples from pericoronitis patients. The study revealed the strong relation between risk of pericoronitis and the presence of Tf. Individuals who have Tf in their samples present with an almost eight times relative risk of pericoronitis as the individuals with an absence of Tf in their samples. CONCLUSION: Tf plays an important role in the development of clinical symptoms related to pericoronitis.

[PCR rationale for use of oral cephalosporins by oral surgery procedures].

The article presents the experience of PCR detection of DNA of pathogenic germs inducing odontogenic inflammation. Pus samples of 48 patients aged 18 to 68 years undergoing oral surgery because of apical periodontal lesions and pericoronitis. The results showed microorganisms associations revealed by PCR are sensitive to III generation cephalosporins. Effective oral regimen included 400 mg Ceftibuten once daily. The PCR results thus served as a rationale for use of oral cephalosporins by oral surgery procedures proved by clinical and immunological data in postoperative period.

Molecular analysis of 16S rRNA genes identifies potentially periodontal pathogenic bacteria and archaea in the plaque of partially erupted third molars.

PURPOSE: Small subunit rRNA sequencing and phylogenetic analysis were used to identify cultivable and uncultivable microorganisms present in the dental plaque of symptomatic and asymptomatic partially erupted third molars to determine the prevalence of putative periodontal pathogens in pericoronal sites. MATERIALS AND METHODS: Template DNA prepared from subgingival plaque collected from partially erupted symptomatic and asymptomatic mandibular third molars and healthy incisors was used in polymerase chain reaction with broad-range oligonucleotide primers to amplify 16S rRNA bacterial and archaeal genes. Amplicons were cloned, sequenced, and compared with known nucleotide sequences in online databases to identify the microorganisms present. RESULTS: Two thousand three hundred two clones from the plaque of 12 patients carried bacterial sequences from 63 genera belonging to 11 phyla, including members of the uncultivable TM7, SR1, and Chloroflexi, and difficult-to-cultivate Synergistetes and Spirochaetes. Dialister invisus, Filifactor alocis, Fusobacterium nucleatum, Porphyromonas endodontalis, Prevotella denticola, Tannerella forsythia, and Treponema denticola, which have been associated with periodontal disease, were found in significantly greater abundance in pericoronal compared with incisor sites. Dialister invisus and F nucleatum were found in greater abundance in sites exhibiting clinical symptoms. The archaeal species, Methanobrevibacter oralis, which has been associated with severe periodontitis, was found in 3 symptomatic patients. CONCLUSIONS: These findings have provided new insights into the complex microbiota of pericoronitis. Several bacterial and archaeal species implicated in periodontal disease were recovered in greater incidence and abundance from the plaque of partially erupted third molars compared with incisors, supporting the hypothesis that the pericoronal region may provide a favored niche for periodontal pathogens in otherwise healthy mouths.

Is dental treatment of an infected tooth a risk factor for locally invasive spread of infection?

PURPOSE: To determine the impact of antecedent dental procedures and dental health on the course of odontogenic maxillofacial infections requiring hospital care. PATIENTS AND METHODS: In this retrospective cohort study in a referral center, we evaluated medical records and panoramic radiographs of all patients admitted because of odontogenic maxillofacial infection (n = 84). The predictor variables were preceding dental treatment, antimicrobial therapy, and dental health. The outcome variables comprised infection parameters, length of stay, need for intensive care, and management during hospitalization. RESULTS: The mean age of the patients was 43.2 ± 16.5 years and 60% were men. Dental procedure preceded the spread of the infection in 49 cases (58%): endodontic treatment (n = 22), tooth extraction (n = 19), and minor first aid (n = 8). Twenty-seven patients had not received any dental or antimicrobial treatment in the recent past. Antimicrobial treatment alone had been given to 8 patients. Patients without preceding treatment had the highest C-reactive protein levels on admission and at maximum (P = .020 and P = .011) and the highest white blood cell counts on admission (P = .011). Their length of stay was also longer, and they needed intensive care more often than the other patients. Maximum C-reactive protein levels and white blood cell counts between treatment groups did not significantly differ from each other. CONCLUSIONS: The systemic response to the infection was strongest and the course of the infection most severe in the absence of preceding dental treatment and in patients with poor dental health. All types of dental treatment contributed to a less severe course of infection.

Spread of odontogenic infections in Port Harcourt, Nigeria.

PURPOSE: Odontogenic infections constitute a substantial portion of diseases encountered by oral and maxillofacial surgeons. Infections start from dental tissues and sometimes rapidly spread to contiguous spaces. The consequence is a fulminant disease with significant morbidity and mortality. The study was aimed at studying the pattern of spread, approach to management, and outcome of these infections at a Nigerian teaching hospital. PATIENTS AND METHODS: A retrospective study of all patients with orofacial infections who presented to our center over an 18-month period was carried out. The medical records were reviewed to retrieve the following: age, gender, source of infection, anatomic fascial spaces involved, associated medical conditions, various treatment modalities, types of antibiotics administered, causative micro-organisms, length of stay in the hospital, and any complications encountered. Infections were classified into 2 categories: those that are confined to the dentoalveolar tissues belong to category I, and those that have spread into the local/regional soft tissue spaces and beyond belong to category II. RESULTS: Odontogenic infections constituted 11.3% of the total oral and maxillofacial surgery cases. A total of 261 patients were treated for odontogenic infections. There were 146 female patients (59.8%) and 98 male patients (40.2%) in the first category, whereas the second category comprised 10 male patients (58.8%) and 7 female patients (41.2%). The fascial spaces involved, in descending order, were submasseteric in 10 (22.7%), submandibular in 9 (20.5%), and sublingual in 6 (13.6%). The causative micro-organisms commonly found were Klebsiella and Streptococcus spp. Incision and drainage were performed in the 17 cases with spreading infection. Amoxicillin, amoxicillin/clavulanate, and metronidazole were the most routinely administered antibiotics. CONCLUSIONS: Our experience shows that delay in presentation, self-medication, aging, male gender, and unusual causative agents are some of the factors associated with spread. Therefore efforts must be made to further improve public dental awareness.

Microbial profile of symptomatic pericoronitis lesions: a cross-sectional study.

OBJECTIVE: The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd. METHODOLOGY: Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique. RESULTS: Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites. CONCLUSION: The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.

Effect of Mercurius solubilis on the bacteriological response in the alveolitis process in rats.

OBJECTIVE: The purpose of this study was to assess the bacteriological response in alveolitis in rats treated with the homeopathic medicine Merc solubilis (Merc sol.) 12 cH. METHODS: The study was randomized and observer blind. The animals were anesthetized and the upper right incisor extracted resulting in alveolitis. Animals were randomly assigned to groups (n=18/group): Water control, Alcohol control and Merc sol. 12 cH. These groups were subsequently divided into 3 subgroups (n=6/subgroup): Early Euthanasia (EE), Mid Euthanasia (ME) and Late Euthanasia (LE), killed at the 6th, 15th and 21st days respectively. The perialveolar microbiota was collected by swab in Brain Heart Infusion (BHI) for seeding and bacterioscopy. After seeding, the Petri dishes were incubated at 37 degrees C for 48 h. RESULTS: Quantitative and qualitative changes were observed in the perialveolar microbiota when the groups were compared. Water control and Alcohol control had the highest counts of pathogenic bacteria, the microbiotica of the Merc sol. group remained closer to normal. CONCLUSIONS: Merc sol. 12 cH did not reduce bacterial growth, but the microbiotica remained within the parameters of normality, obtaining the best results at 21 days after treatment.

Update on bacteraemia related to dental procedures.

The oral microbiota is highly diverse consisting of more than 700 bacterial species. Notably, only half of these species can so far be cultivated. This may have an impact on how to interpret negative findings in blood cultures. The present paper gives an overview of the current knowledge on bacteraemia after common oral procedures such as tooth extraction, root scaling, periodontal probing, suture removal, orthodontic treatment, tooth restoration, non-surgical root canal treatment, chewing, tooth brushing, flossing, and use of tooth sticks. The possible relationship between periodontitis-related bacteraemia and cardiovascular diseases is also considered, as well as bacteraemia after oral procedures compared to procedures representing irritation or minor trauma to other mucosae. It may be that patients never seeing a dentist are more unfitted as blood donors than those recently having seen one.

The relationship between pericoronitis, wisdom teeth, putative periodontal pathogens and the host response.

PURPOSE: To review the literature concerning pericoronitis, in particular the nature of the lesion and its aetiology, what factors may be used to predict if some patients would benefit from early removal of third molars, and if a scoring system can be developed for this purpose. METHOD AND MATERIALS: A literature search using PubMed and the facilities of the Dublin Dental Hospital (DDH) library were used to gather the relevent information. PubMed lists all of the journals available in the DDH library and was used to identify relevent papers, which were then retrieved from the shelves and stacks with the help of library staff. The key word used was 'pericoronitis'. RESULTS: The studies reviewed assert that the bacteriology of pericoronitis is predominantly anaerobic in character, yet no causative species has been identified. Marker organisms for periodontitis were not generally isolated. Host factors examined in various studies were the inflammatory markers interleukin 1b and prostaglandin E2, and the immunological responses of neutrophils, macrophages, natural killer cells, T cells, helper T cells and suppressor/cytotoxic T cells. While all of these factors, with the exception of prostaglandin E2, tend to be elevated in cases of pericoronitis, both symptomatic and asymptomatic, no clearcut measurable entity has emerged that can be used as a predictive marker. CONCLUSION: A hypothesised scoring system to predict which patients would benefit from early removal of asymptomatic impacted lower third molars would be clinically advantageous in justifying prophylactic third molar surgery, but is not yet feasible or proven.

Periodontal pathogens in erupting third molars of periodontally healthy subjects.

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.

Antibiotic susceptibility of the bacteria causing odontogenic infections.

AIMS: An evaluation is made of bacterial species and susceptibility to various antibiotics used in application to odontogenic infections of periapical location and in pericoronitis of the lower third molar, with the aim of optimizing the antibiotherapy of such infections and thus preventing unnecessary side effects and over-treatment. MATERIAL AND METHODS: Sixty-four patients with odontogenic infection were selected on the basis of a series of inclusion and exclusion criteria. Samples were collected from lesions under maximally aseptic conditions, avoiding oral saprophytic contamination. The samples were cultured and incubated under aerobic and anaerobic conditions, followed by bacteriological identification and antibiotic susceptibility testing. RESULTS: A total of 184 bacterial strains were isolated and identified, comprising grampositive facultative anaerobes (68%), gramnegative strict anaerobes (30%) and grampositive facultative anaerobes (2%). Regardless of the origin of the odontogenic infection, the causal bacteria yielded the best results in terms of increased sensitivity and lesser resistance with amoxicillin / clavulanate and amoxicillin, respectively (p<0.05). DISCUSSION: There are increasingly numerous reports in the literature of growing bacterial resistance to antibiotics in infectious processes affecting non-buccodental territories. This same tendency has not been observed in relation to oral infections, though important resistance has been documented for certain concrete antibiotics. According to our results, the common-use antibiotics with the greatest sensitivity and lowest resistance were shown to be amoxicillin/clavulanate followed by amoxicillin alone.

Microbial profile of symptomatic pericoronitis lesions: a cross-sectional study

Abstract Objective: The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd. Methodology: Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique. Results: Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites. Conclusion: The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.

Malignant lymphoma presenting as pericoronitis. A case report.

A case of diffuse, large-cell non-Hodgkin's lymphoma presenting as pericoronitis in the oral cavity is described. The diagnostic pitfalls are briefly discussed.

Inflammatory cells and bacteria in pericoronal exudates from acute pericoronitis.

The present work is one in a series of studies carried out to verify the relationship between bacteria and gingival tissues in pericoronitis. Exudates from 6 cases of acute pericoronitis were examined by light and electron microscopy, including ultrathin sections and negative staining. While bacterial phagocytosis was prevalent in all the exudates studied, spirochetes, which were the predominant microorganisms, were not observed being phagocytized by PMNs or macrophages. The presence of spirochetes in pericoronitis as compared with acute necrotizing ulcerative gingivitis is discussed.

Pericoronitis and tonsillitis: clinical and darkfield microscopy findings.

OBJECTIVE: Upper respiratory tract infections and tonsillitis and pharyngitis in particular increase the risk of lower third molar pericoronitis. The study was made to investigate clinical and microbiologic associations between pericoronitis and tonsillitis. STUDY DESIGN: The subjects were 20-year-old Finnish male conscripts. Thirty-eight patients had tonsillitis without and 33 patients had tonsillitis with a symptom-free erupting lower third molar; 27 patients had pericoronitis but healthy tonsils. All subjects were examined clinically. Bacterial samples were taken from healthy and diseased tonsils and from healthy and diseased third molar pericoronal pockets. The microbes were classified morphologically with the use of a darkfield microscope. RESULTS: Eighty-two percent of infected tonsils had deep crypts and 52% of them exudated pus compared with 36% (p < 0.001) and 0% (p < 0.001) in healthy tonsils, respectively. Infected lower third molars were less than half erupted and had on average 8.8 mm deep pericoronal pockets compared with pockets 5.5 mm deep recorded in symptom-free cases (p < 0.001). Spirochetes were more common in infected pockets than in symptom-free cases comprising 8.2% versus 3.0% of the total bacterial count (p = 0.044). Rods were more common in infected tonsils than healthy ones (8.9% versus 4.8%, p = 0.041). CONCLUSION: There were similarities in morphologic microbiota of pericoronitis and tonsillitis. However, clinical findings of tonsils did not appear to link with the findings of third molars.

Bacteriologic features and antimicrobial susceptibility in isolates from orofacial odontogenic infections.

OBJECTIVE: The aim of this study was to obtain information for an effective antimicrobial therapy against orofacial odontogenic infections; such information was obtained from recent bacteriologic features and antimicrobial susceptibility data. STUDY DESIGN: The bacteriology and antimicrobial susceptibility of major pathogens in 163 patients with orofacial odontogenic infections to 7 antibiotics was examined. RESULTS: Mixed infection of strict anaerobes with facultative anaerobes (especially viridans streptococci) was observed most often in dentoalveolar infections, periodontitis, and pericoronitis. Penicillin (penicillin G) was effective against almost all pathogens, although it did not work well against beta-lactamase-positive Prevotella. Cefmetazole was effective against all test pathogens. Erythromycin was ineffective against viridans streptococci and most Fusobacterium. Clindamycin exerted a strong antimicrobial activity on anaerobes. Minocycline was effective against almost all the test pathogens. The antimicrobial activity of levofloxacin against viridans streptococci was not strong. CONCLUSIONS: An antibiotic that carries out antimicrobial activity against both viridans streptococci and oral anaerobes should be suitable for treatment of dentoalveolar infection, periodontitis, and pericoronitis. Penicillin remains effective as an antimicrobial against most major pathogens in orofacial odontogenic infections. Cefmetazole, clindamycin, and minocycline may be effective against most pathogens, including penicillin-unsusceptible bacteria.

Microbiology of mandibular third molar pericoronitis: incidence of beta-lactamase-producing bacteria.

OBJECTIVES: The purpose of this study was to evaluate the predominant flora associated with pericoronitis in third molars and to investigate the presence of beta-lactamase-producing strains. STUDY DESIGN: The third molars in 26 adults were evaluated by cultures with nonselective media and with selective media containing amoxicillin, pristinamycin, spiramycin, metronidazole, and spiramycin plus metronidazole. RESULTS: In the majority of cases (19/26), the flora found in an anaerobic atmosphere predominated. Obligate anaerobes were present in 21 of the 26 samples. The bacteria most commonly detected were alpha-hemolytic streptococci (26/26) and the genera Prevotella (15/26), Veillonella (15/26), Bacteroides (9/26), and Capnocytophaga (9/26). Amoxicillin and pristinamycin were the most active in reducing the anaerobic cultivable counts. beta-Lactamase-producing strains were detected in 9 samples and were mostly bacteria of the genera Prevotella, Staphylococcus, and Bacteroides. CONCLUSIONS: These results highlight (1) the diversity of the microflora associated with pericoronitis and the importance of the anaerobic flora and (2) the existence of selection pressure related to the use of beta-lactams that may culminate in failure of prescribed penicillins.