Sevgi Ciftci

Salivary detection of periodontopathic bacteria and periodontal health status in dental students.

OBJECTIVE Saliva may become a potential source of contamination through vertical and horizontal transmissions as well as cross-infections. This study aims to use saliva as a screening tool to detect putative periodontal pathogens in a young population with fairly good oral hygiene. MATERIALS AND METHODS Stimulated saliva samples were obtained from 134 dental students (20.5+/-1 years, range 18-22 years). Among those, 77 subjects also completed a periodontal examination including attachment loss, modified dental, gingival and plaque indices (AL, mDI, GI and PI). The test bacteria were identified using a 16S rRNA-based PCR detection method. RESULTS One or more of the test bacteria was found in 67% of the subjects. Prevotella nigrescens was detected as single bacterium in 16% of the subjects followed by Treponema denticola (4%), Porphyromonas gingivalis (2%), Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans (1%) and Tannerella forsythia (1%). Two or more pathogens were detected in 42% of the subjects. Clinical examination revealed health with no attachment loss (AL) in 84% of the students. In no AL group, 38% of the students were pathogen free while this was 25% for students in localized AL group (p>0.05). There was a statistically significant association between the detection of salivary periodontal pathogen in general and higher PI (p=0.018) and GI (p=0.043). CONCLUSION Within the limits of this study, it is possible to detect all six periodontal pathogens in the saliva of dental students. Although a correlation can be observed between the presence of salivary periodontal pathogen and clinical signs of inflammation such as plaque accumulation and gingival bleeding, detection of specific bacteria in saliva is not related to the presence of localized AL based on the presented study population.

Analysis of potential antiviral resistance mutation profiles within the HBV reverse transcriptase in untreated chronic hepatitis B patients using an ultra-deep pyrosequencing method ☆ ☆☆

The potential antiviral resistance mutations within hepatitis B virus (HBV) reverse transcriptase (RT) region for nucleos(t)ide analogues (NA) are not well known. Especially, the effect of pre-existing antiviral drug resistance mutations in untreated patients in comparison to the resistance developed after treatment is not still clear. Sixteen naive chronic hepatitis B patients were studied. None of the patients had received NA treatment prior to the serum samples being collected. Forty-two potential NA resistance (NAr) mutation sites were screened by ultra-deep pyrosequencing (UDPS). After therapy, mutations conferring treatment resistance were detected by LiPA. Serum samples taken before treatment showed no classic primary or compensatory/secondary drug resistance mutations. However, NAr mutations found in 6 isolates (37.5%) involved 7 positions including rtL91I, rtT128I, rtQ215P, rtF221Y, rtN238D, rtC256S, and rtI266G. Substitutions at 3 NAr mutation sites (rtT128I, rtN238D, and rtC256S) were detected in 3 unresponsive patients developing drug resistance after NA treatment. One patient with rtI266G mutation also developed drug resistance after lamivudine (LAM) therapy. However, the relationship between rtI266G mutation and NA drug resistance was not previously reported. These results suggest that association of potential mutations besides the primary and secondary/compensatory resistance mutations should be investigated. Investigation of NAr mutations before treatment may be important for the success of the treatment.

Relationship between oral anaerobic bacteria and otitis media with effusion.

Objective: In this study hypothesing the translocation of oral bacteria from oropharynx into the middle ear cavity may be involved in the pathogenesis of otitis media with effusion (OME), we aimed to investigate the presence and similarity of Fusobacterium nucleatum and Treponema denticola in saliva, nasopharyngeal secretion and the middle ear effusion samples from the children with OME. Methods: Totally 20 children with OME undergoing myringotomy and ventilation tube placement were attended. Stimulated saliva samples were collected after otorhinolaryngological and oral examinations were done. The middle ear effusion and nasopharyngeal secretions were collected during the operations. The presence of F. nucleatum and T. denticola were detected using 16SrRNA-based PCR. The clonal similarities of the bacteria were detected in the samples which the same bacteria had been detected in each samples of the same child. After DNA sequencing, clonal similarity was determined by 16SrRNA gene clone library analysis. The sequences from each clone were compared with similar sequences of reference organisms by FASTA search. Results: T. denticola was detected only in four (20%) saliva and in one (5%) nasopharyngeal sample. F. nucleatum was detected in 11 (55%) saliva, eight (40%) nasopharyngeal and six (30%) middle ear effusion samples. Sequences from F.nucleatum clones derived from three different anatomic sites within patients were similar in 33% of OME patients, indicating their genetic relatedness. Conclusions: Bacteria involved in this process most likely originate from the oropharynx since they show a close genetic relatedness with their oropharyngeal counterparts.

In Vitro Antifungal Activity of Ankaferd Blood Stopper Against Candida albicans

BACKGROUND Candida albicans is a memeber of the oral flora that can lead to various complications in immunosupresive patients after oral surgery processes. Ankaferd Blood Stopper® (ABS) is a medical plant extract that is safe to use in patients with dental surgery bleedings in Turkey. OBJECTIVE The study evaluated the antifungal activity of ABS medicinal plant extract against C albicans using the agar diffusion and broth microdilution methods. METHODS The plant extract antifungal activity was assessed in vitro either by applying the ABS extract directly and by applying different concentrations of ABS onto Candida culture. For these experiments, an agar diffusion method was used. To determine the minimum inhibitory concentration (MIC), a broth microdilution method was used. RESULTS Different volumes of the active substance (10, 20, 30, and 40 μL) were applied onto Candida (0.5 McFarland solution) cultivated plate; Candida growth was inhibited in accordance with the volumes of ABS. However, when various dilutions of ABS (1:2, 1:20, 1:40, and 1:80) were added as drops containing 20 μL, no antifungal effects were found. No MIC values were identified using broth microdilution. When different dilutions of ABS containing 100 μL of 0.5 McFarland solution of C albicans were cultured depending on the time (10, 20, 30, and 40 minutes), the effect of the duration was not significant. CONCLUSION The various tests were carried out to investigate antifungal effects of ABS on Candida, but none were found.

Detection of the anaerobic bacteria in the odontogenic cyst fluids using polymerase chain reaction (PCR) method

Odontogenic cysts are slow growing lesions which are formed by epithelium. They may reach to a substantial size without symptoms for a long time. Radicular cysts’ (RCs) and odontogenic keratocysts’ (OKCs) are common odontogenic cysts of jaws. The main purpose of this study is to evaluate if anaerobic bacteria play a role in the pathogenesis of the RCs and OKCs fluids by polymerase chain reaction (PCR). Odontogenic cyst fluid samples with a history of infection were collected from a total of 28 odontogenic cysts consisting of 16 samples of OKCs and 12 samples of RCs. Anaerobic bacteria detection were performed by PCR based on bacterial 16S rRNA genes. Porphyromonas gingivalis existed more frequently compared to the other bacteria, in all samples (39.2%). Following this, F. nucleatum (32.1%), Provetella intermedia and Campylobacter rectus ( 25.5%), Treponema denticola (25%), Provetella nigrescens and Tannerella forsythia (17.8%), Dialister pneumosintes (14.2%), Filifactor alocis (10.7%), Porphyromonas endodontalis and Provetella pallens (7.1%) were seen. The 58.3% of the Fusobacterium nucleatum positive cyst fluids were in the RCs group. In D. pneumosintes positive cysts liquid samples, C. rectus was found to be positive (p=0.025). The same correlation was observed between F. alocis and C. rectus (p= 0.003). On the other hand, in F. alocis positive cysts liquid samples, F. nucleatum also was found to be positive (p=0.026). Odontogenic cysts fluid contained numerous anaerobic bacteria of various types, thus suggesting that oral bacteria may cause symptoms in odontogenic cyst fluids. Further studies are needed to assess the role of these bacteria in the pathogenesis of odontogenic cysts.

An Atypical Form of Necrotizing Periodontitis

BACKGROUND Necrotizing ulcerative gingivitis/periodontitis are considered necrotizing periodontal diseases. This case report presents an atypical form of necrotizing periodontitis, which does not fit into this classification. METHODS A 12-year-old child was referred to our clinic for gingival inflammation, extensive alveolar bone loss, and tooth mobility. Clinical and microbiologic examinations were carried out, and radiographs were taken. Clinical examination revealed soft and hard tissue destruction up to the mucogingival junction at the right maxillary premolar and mandibular incisors. Unusual infections or abnormalities in systemic functions were not detected through clinical and laboratory evaluations made at the Pediatrics Department, Istanbul University. Although an intensive established treatment protocol for necrotizing periodontitis was completed, management of long-standing health conditions could not be achieved because of recurrence of the disease, which caused us to repeat this treatment protocol at short intervals. RESULTS Investigation led to a diagnosis of an atypical form of necrotizing periodontitis because the disease had a recurrent acute phase even under a standard treatment protocol. CONCLUSIONS Our patient exhibits an unusual, necrotizing form of periodontal disease. The reason for the rapid rate of periodontal disease progression remains unclear.

Species and number of bacterium may alternate IL-1β levels in the odontogenic cyst fluid

Abstract Objectives The role of oral bacteria in the etiopathogenesis of odontogenic cysts (OC) is controversial. Immune response is regulated by the cytokines secreted during infection. This study aims to describe the association in between bacteria and levels of cytokines in OC. Methods Infected OC fluid samples were obtained from 25 odontogenic keratocysts and 14 radicular cysts (RC). Bacteria detection was performed by polymerase chain reaction on bacterial 16S rRNA genes. Cytokine levels in OC fluids were determined using “luminex” method. Results Porphyromonas gingivalis was the most common bacteria in all samples (41.03%). Bacteria species number was higher in RCs. The significant difference was detected in terms of interleukine (IL)-1β levels to the number of bacteria contained in cyst fluids (p<0.05). IL1-β level of cyst fluid group containing three or more species of bacteria increased compared with cyst fluid group containing two types of bacteria (p<0.05). IL-1β level was high in cyst fluids with Campylobacter rectus and Treponema denticola or with three or more bacteria species. IL-1β level was higher in the cyst fluids with Enterococcus faecalis negative than E. faecalis positives. Conclusions Our results suggest that species and the number of bacterium may differ IL-1β levels in the OC fluid.