Antioxidant and antiproliferative potential of biosurfactants isolated from Lactobacillus casei and their anti-biofilm effect in oral Staphylococcus aureus strains.

Biosurfactants also called bioemulsifiers are amphipathic compounds produced by many microorganisms that allow them to exhibit a wide range of biological activities. The aim of this study was to determine the antioxidant and antiproliferative potential of biosurfactants isolated from Lactobacillus casei and to assess their anti-adhesive and anti-biofilm abilities against oral opportunistic Staphylococcus aureus strains. The antioxidant activity of biosurfactant was evaluated using the in vitro scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The antiproliferative activity was determined on epithelial cell line (HEp-2) by the Methylthiazole tetrazolium (MTT) reduction assay. The anti-adhesive and antibiofilm activity against S. aureus strains were achieved using crystal violet staining. Our results revealed that the DPPH scavenging activity of biosurfactants at 5.0 mg/mL concentration is between 74.6 and 77.3%. Furthermore, biosurfactants showed antiproliferative potency against studied epithelial cells as judged by IC50 and its value ranged from 109.1 ± 0.84 mg/mL to 129.7 ± 0.52 mg/mL. The results of the growth inhibition indicate that biosurfactant BS-LBl was more effective against oral S. aureus strains 9P and 29P with an IC50 of 1.92 ± 0.26 mg/mL and 2.16 ± 0.12 mg/mL respectively. Moreover, both biosurfactants displayed important antibiofilm activity with eradication percentages ranging from 80.22 ± 1.33% to 86.21 ± 2.94% for the BS-LBl, and from 53.38 ± 1.77% to 64.42 ± 2.09% for the BS-LZ9. Our findings demonstrate that biosurfactants from L. casei strains exhibited considerable antioxidant and antiproliferative potencies and were able to inhibit oral S. aureus strains with important antibiofilm efficacy. They could have a promising role in the prevention of oral diseases.

Assessment of adhesion, invasion and cytotoxicity potential of oral Staphylococcus aureus strains.

The oral cavity is regarded as a relevant site for Staphylococcus aureus colonization. However, characterization of virulence mechanisms of oral S. aureus remains to be uncovered. In this study, twenty one S. aureus strains isolated from the oral cavity of Tunisian patients were screened for adherence, invasion and cytotoxicity against HeLa cells. In addition, the presence of adhesins (icaA, icaD, can, fnbA and fnbB) and α-hemolysin (hla) genes in each strain was achieved by polymerase chain reaction (PCR). Our finding revealed that oral S. aureus strains were able to adhere and invade epithelial cells, with variable degrees (P < 0.05). Moreover they exhibited either low (23.8%) or moderate (76.2%) cytotoxic effects. In addition 76.2% of strains were icaA and icaD positive and 90.5% harbor both the fnbA and the fnbB gene. While the cna gene was detected in 12 strains (57.2%). Furthermore, the hla gene encoding the α-toxin was found in 52.4% of the isolates. All these virulence factors give to S. aureus the right qualities to become a redoubtable pathogen associated to oral infections.

Adhesive properties and extracellular enzymatic activity of Staphylococcus aureus strains isolated from oral cavity.

Staphylococcus aureus is one of prominent bacterial pathogen that occurs in oral region. In this study, 21 strains of S. aureus isolated from the oral cavity of Tunisian patients were investigated for slime production using Congo red agar method (CRA) and adherence assay. Biofilm formation of oral isolates on orthodontic biomaterials (Bis-GMA and PMMA) was also evaluated by MTT reduction assay. In addition, the production of hydrolytic enzymes by S. aureus strains was analyzed and the presence of protease, lipase and ß-hemolysin genes (sspA, sspB, geh, hlb) was achieved by polymerase chain reaction (PCR). Qualitative biofilm production tested on CRA revealed that 91% of strains were slime producers. The result of OD570 showed that five strains isolated from the oral cavity were highly biofilm positive. The metabolic activity of S. aureus biofilm formed on Bis-GMA and PMMA did not differ between tested strains. The atomic force micrographs demonstrated that biofilm formed by S. aureus strains was organized in typical cocci cells attached to each other through production of exopolymeric substances. The production of hydrolytic enzymes showed that all S. aureus strains were protease positive. Lipase (77%) and beta hemolytic (59%) activities were also detected. Among the tested strains, 17 were positive for sspA, sspB and hlb genes. While only ten S. aureus strains harbor the geh gene (48%). These data highlight the importance of evaluation of biofilm formation and exoenzyme production in oral S. aureus isolates to investigate the role of this pathogen and its impact in oral pathology.

Molecular detection of bacteria associated to dental caries in 4-12-year-old Tunisian children.

The occurrence of several microbial species in the oral cavity of 4-12-year-old Tunisian children was investigated. Samples were taken from 158 children (81 caries actives and 77 caries free). Genomic DNA was extracted and analyzed for the presence of 17 microbial species using a polymerase chain reaction assay. All samples were positive for at least one of the target microbial strains. Streptococcus mutans was the most prevalent species (76.5%) detected in genomic DNA collected from carious lesions. Other prevalent species were Candida spp (63%), Streptococcus salivarius (59%) and Streptococcus oralis (42%). The frequency of Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus casei-group in caries lesions was 29.5%, 34.5% and 22% respectively. Pathogenic bacteria such as Staphylococcus aureus was found in 28.5% of carious lesion samples compared to 15.5% in the control. Frequency of Porphyromonas endodontali, Actinomyces radicidentis and Treponema denticola recovery did not differ significantly between origins of samples. PCR analysis of genomic DNA detect various oral bacteria that differ between caries actives and caries-free children. In addition, the association of same aciduric bacteria (S. mutans, S. salivarius, L. acidophilus) and caries formation was noticed.

Herpes simplex virus infection: Management of primary oral lesions in children.

Primary herpetic gingivostomatitis (PHGS) represents the most observed clinical feature of primary herpes infection with the simplex virus (HSV). It is often caused by HSV-1 and affects children most of the time. Unlike, the majority of primary HSV infections that is asymptomatic. It may be preceded by some prodromal symptoms like fever, anorexia, irritability, malaise, and headache. After the resolution of the primary infection, the virus remains latent in a nervous ganglion. The aim of the present paper was to report a case of severe PHGS with herpetic whitlow in a 10-year-old child.

Antibiotic resistance and adhesion properties of oral Enterococci associated to dental caries.

BACKGROUND: Enterococci are increasingly associated with opportunistic infections in Humans but the role of the oral cavity as a reservoir for this species is unclear. This study aimed to explore the carriage rate of Enterococci in the oral cavity of Tunisian children and their antimicrobial susceptibility to a broad range of antibiotics together with their adherence ability to abiotic and biotic surfaces. RESULTS: In this study, 17 E. faecalis (27.5%) and 4 E. faecium (6.5%) were detected. The identified strains showed resistance to commonly used antibiotics. Among the 17 isolated E. faecalis, 12 strains (71%) were slime producers and 5 strains were non-producers. Among the 4 E. faecium, 2 strains were slime producers. All the tested strains were able to adhere to at least one of the two tested cell lines. Our result showed that 11 E. faecalis and 2 E. faecium strains adhered strongly to Hep-2 as well as to A549 cells. CONCLUSIONS: Drugs resistance and strong biofilm production abilities together with a high phenotypic adhesion to host cells are important equipment in E. faecalis and E. faecium which lead to their oral cavity colonization and focal infections.

An innovative technique to treat epulis fissuratum: A case report.

The purpose of this article is to present a case demonstrating the treatment of epulis fissuratum due to a poorly adapted prosthesis using a single surgical procedure involving conventional excision and free gingival graft. We, herein, present a case involving a 58-year-old patient with epulis fissuratum. Treatment of this case was essential due to the masticatory problems. This technique can be effective to deepen the height of the residual alveolar ridge and to increase the amount of keratinized tissue.

[The role of piezosurgery in the treatment of a rare case of superinfected cemento-osseous dysplasia caused by actinomyces: a case report]. / L´intérêt de la piézochirurgie dans le traitement d'une dysplasie cémento-osseuse surinfectée par actinomycose: à propos d'un cas.

Cemento-osseous dysplasia is a benign fibro-osseous lesion affecting the alveolar bone. It is classified into three forms: periapical, focal or florid dysplasia. It is often asymptomatic and fortuitously discovered during a routine radiological examination. However, it may become symptomatic after superinfection, after patient's exposure to oral bacterial flora. We here report a case of florid cemento-osseous dysplasia associated with actinomycosis of bone in a 53-year-old Tunisian woman. This superinfection has been rarely reported in the literature; Boolean Searching on PubMed for the keywords "cemento-osseous dysplasia AND actinomyces" displays a single article (Smith et al. 2011). The treatment of actinomycosis infection often requires long-term antibiotic therapy, sometimes associated with surgical debridement, as in the case of this patient who underwent piezosurgery to treat dysplasia and necrotic bone.

Epidermoid cyst of the buccal mucosa-An uncommon entity: Case report and literature review.

Epidermoid cyst of the buccal mucosa is rare. Nevertheless, it must be included in the differential diagnosis of swelling in this area. The diagnosis is based on anatomopathological examination. The surgical enucleation is the gold standard of treatment.

Cell surface hydrophobicity, biofilm formation, adhesives properties and molecular detection of adhesins genes in Staphylococcus aureus associated to dental caries.

Staphylococcus aureus is an important pathogen that forms biofilm. In this study, 22 S. aureus have been isolated from the oral cavity of Tunisian children and investigated for slime production using Congo red agar method (CRA) and semi quantitative adherence assay. The hydrophobicity of strains was evaluated by the microbial adhesion to solvent (MATS) test. The adherence of S. aureus to Hep2 cells was examined by light microscopy. The genes implicated in adhesion (icaA, icaD, fnbA, cna, clfA) were detected. Polymerase chain reaction was used. The affinity to hexadecane was low proving a hydrophilic character of all the studied strains. Qualitative biofilm production revealed that 50% of strains were slime producers. The result of OD(570) showed that four strains isolated from the caries-active children were highly biofilm positive. In addition, 50% of strains were icaA and icaD positive. The fnbA gene was present in 59.1% of isolated strains. Furthermore, 54.5% of strains harboured the cna gene, 9.1% were clfA positive and 50% were hla positive. Quantitative adherence varied considerably among the tested strains. All strains showed adherence to Hep2 cells. However, the level of adhesion varied between strains as follows. Seven strains were defined as moderately adherent, nine as strongly adherent and six as weakly adherent. The percentage of infected cells ranged from 15+/-0.0376 (B374) to 96+/-0.019 (B295) and the total number of bacteria per 100 cells ranged from 15+/-5.1 (B374) to 1824+/-30.1 (B295).

Adhesive properties and hydrolytic enzymes of oral Candida albicans strains.

Several virulence factors in Candida albicans strains such as production of hydrolytic enzymes and biofilm formation on surfaces and cells can contribute to their pathogenicity. For this, control of this opportunistic yeast is one of the factors reducing the nosocomial infection. The aim of this study was to investigate biofilm formation on polystyrene and polymethylmethacrylate and the production of hydrolytic enzymes in Candida albicans strains isolated from the oral cavity of patients suffering from denture stomatitis. All strains were identified by macroscopic, microscopic analysis and the ID 32 C system. Our results showed that 50% of the total strains produced phospholipase. Furthermore, protease activity was detected in seven (35%) strains. All Candida albicans strains were beta haemolytic. All C. albicans strains adhered to polystyrene 96-well microtiter plate at different degrees, and the metabolic activity of C. albicans biofilm formed on polymethylmethacrylate did not differ between tested strains. The atomic force micrographs demonstrated that biofilm of Candida albicans strains was organized in small colonies with budding cells.

Piezoelectric-Assisted Removal of a Mandibular Cementoossifying Fibroma: An Innovative Technique.

Diagnosis of cementoossifying fibroma is oriented by the clinical and radiological aspects of the lesion. Histology confirms the diagnosis. Treatment is surgical with enucleation-resection depending on the lesion size or wider resection with bone reconstruction in cases of large fibromas. The use of piezoelectric bone surgery is associated with low surgical trauma, exceptional precision, and fast healing response. It also allows easy performance of complex osteotomy and reduces the necessary dimensions of mucoperiosteal dissection. The purpose of the present article was to present the advantages of piezoelectric-assisted surgical removal of a cementoosseous fibroma of the mandible and to provide a precise description of the procedure using atraumatic surgery.

Gingival Melanin Depigmentation by 808 nm Diode Laser: Report of a Case.

Gingival hyperpigmentation frequently poses an aesthetic problem, especially in patients with gingival smile. This paper presents the use of a 808 nm pulsed diode laser for gingival depigmentation in a 22-year-old male patient, with a frequency of 20,000 Hz, a peak power of 5 W, and a pulse width of 26 microseconds, using a 400 nm flexible optic fiber. The hyperpigmented gingival tissue was removed without bleeding or postoperative pain. Three weeks later, the gum resumed its normal, firm, and pink appearance. No significant recurrence was noted after a follow-up of 4 months. However, perfect control of this device is necessary to avoid certain consequences such as bone exposure or gingival fenestrations.

Mucosal coronally positioned flap technique for management of excessive gingival display.

Improvement of smile esthetics is a major goal of modern dentistry. Various treatment modalities have been proposed to correct excessive gingival display, depending on intraoral or extraoral etiologies. This report aimed to document the use of mucosal coronally positioned flap called surgical lip repositioning technique for the management of a gummy smile associated with vertical maxillary excess. The procedure restricts the muscle pull of the elevator lip muscles by shortening the vestibule, thus reducing the gingival display when smiling. Rapid surgical healing with minimal postoperative sequelae was observed. The follow up examinations showed esthetic satisfaction up to 6 months postoperatively, at the end of one year a partial relapse was observed. Although the short-term stable results of lip repositioning surgery appear satisfying postoperatively, its utility as a long-term treatment option remains questionable. More studies with larger sample size and long-term follow-up are necessary to establish the level of scientific evidence of this procedure.

Cone-beam computed tomography exploration and surgical management of palatal, inverted, and impacted mesiodens.

Supernumerary teeth are extra teeth or toothlike structures which may have either erupted or unerupted in addition to the 20 deciduous teeth and the 32 permanent teeth. Mesiodens is one of these located in the midline between the two central incisors. Their presence may give rise to a variety of clinical problems. This paper describes a rare case of palatal placed, inverted and impacted mesiodens associated to two supernumerary teeth which were detected during a radiographic examination for delayed eruption of permanent central incisors in the case of a healthy 8-year-old girl monitored at the oral surgery service while discussing the usefulness of cone beam computed tomography for accurate diagnosis and management.

Peripheral Ossifying Fibroma: A Review and Case Report

The peripheral ossifying fibroma appears as a solitary nodule, frequently occurring in the anterior maxilla. It begins in the cells of the periodontal ligament, and it is more common in children and young adults. Recent lesions are asymptomatic and patients can ignore their presence. However, in the absence of any treatment, they slowly increase in volume. In this paper, we describe a case report of a 40-year-old female patient reported with growth on gingiva in the upper left maxillary region of 1 year ago. The definitive diagnosis is established by histological analyze, which reveals the existence of highly cellular connective tissue with focal calcifications. Surgery is the treatment of choice, though the recurrence rate can reach 20%.

Molecular investigation of macrolide and Tetracycline resistances in oral bacteria isolated from Tunisian children.

OBJECTIVE: This study aims to investigate the antibiotic susceptibility of strains isolated from the oral cavity of Tunisian children. DESIGN: Strains were isolated from the oral cavity of Tunisian children (60 caries-actives and 30 caries-free). Molecular characterization was assessed by PCR assay to detect erythromycin methylase gene (ermB), macrolide efflux (mefI) and tetracycline resistance genes (tetM and tetO). RESULTS: A total of 21 species were isolated and identified. Antimicrobial susceptibility revealed that the resistance rate to antibiotics was as follow: erythromycin (22%), tetracycline (15.6%), cefotaxim, (7.3%), trimethoprim-sulfamethoxazol (37.6%), nitrofurantoine (2.8%), pristinamycin (17.4%), quinupristin-dalfopristin (15.6%), and rifampicin (3.7%). The majority of mefI positive strains (31.2%) were isolated from the carious children (n=34) in comparison with 8.25% from the control group (n=9). In addition, frequency of strains caring resistance genes were as follow: 12.84% for ermB, 9.17% for tetM and 27.52% for tetO from the carious children in comparison to 0.092%, 3.67% and 3.67% from the caries free group respectively. CONCLUSION: Multi-resistance strains towards macrolides and tetracycline were recorded. The majority of strains carrying antibiotics resistance genes were isolated from the caries active children. The presence of multi-resistant bacteria in the oral cavity can be the major cause of antibiotic prophylaxis failure in dental practise.