Occurrence of some oral potentially pathogenic microorganisms and their associated risk factors

Background: The human mouth harbors one of the most diverse microbiomes in the human body. Multiple factors might affect the composition of oral flora, such as oral hygienic practices. Disturbance in the composition of the oral flora might lead to local as well as systemic diseases

Objective[s]: To estimate the occurrence of some oral potentially pathogenic microorganisms and their associated risk factors, as well as their association with dental caries

Methods: Saliva samples were collected from 130 participants affiliated to the High Institute of Public Health [HIPH] including university teaching staff/ postgraduate students, administrative employees and workers. A questionnaire sheet was completed for everyone. It included demographic data, clinical data as well as oral hygienic practices. The DMFT index was recorded as an index for oral caries. All 130 saliva samples were examined for the presence of Enterobacteriaceae, Streptococcus mutans [S. mutans] and Candida spp. Demographic data, dental hygiene practices, dental complaints as well as the DMFT index were all studied in relation to the studied microbial agents

Results: The most prevalent microorganism among participants was S. mutans [64.6% of isolates] followed by Candida spp [20.8%] then Enterobacteriaceae spp [10%]. Isolates of Enterobacteriaceae spp were distributed as follows: Citrobacter koseri [4.6%], followed by Klebsiella pneumoniae [3.8%], then Klebsiella oxytoca. S. mutans was the only microorganism that was significantly affected by the type of snacks taken between meals [p=0.001]. Among those who had sugary snacks between meals, S. mutans was isolated in 81.3% of them. Candida spp was present in 27.3% of married participants, and this finding was statistically significant. The intake of drinks between meals was also significantly associated with positive Candida cultures [31.1% of participants who took drinks in between meals had positive Candida cultures]. Enterobacteriaceae were significantly less frequently isolated among participants with secondary and university education [5% and 6.5% respectively] compared to uneducated and primarily educated participants [13% and 40% respectively]. None of the studied microorganisms were associated with any specific dental hygienic practice, or specific dental symptoms and signs. The only organism isolated that was significantly associated with DMFT index was S. mutans [p = 0.001]. None of the microorganisms were found to be significantly associated with the presence of any of the other two microorganisms

Conclusion: S. mutans was the most prevalent microorganism among participants and was significantly associated with higher DMFT index. The presence of potentially pathogenic oral microorganisms was influenced mainly by the educational status as well as dietary habits [the intake of sugars and drinks between meals] rather than specific oral hygienic practices

Expression of epithelial membrane antigen [EMA] in oncocytic neoplasms of the salivary glands

Oncocytoma is a rare benign tumors that virtually. Only affect the parotids, particularly in the elderly. It consists of large eosinophilic cells with small compact nuclei [oncocytes] which are typically arranged in solid cords. Oncocytic carcinomas appear to arise from benign oncocytomas or may arise de novo. Seven cases of oncocytomas [Five benign and two malignant] were included in this study. They were stained with periodic acid schiff [PAS] stain for glycogen detection and with monoclonal antibody. Epithelial membrane antigen [EMA] for immunhistochemical staining using the avidin - biotin per-oxidase complex method [ABC]. Results revealed positive reaction of PAS stain in oncocytic cells of both benign and malignant oncocytomas. Homogenous and intra cellular reaction of EMA was detected in benign oncocytomas while patchy and intense reaction was observed in malignant cases revealing the malignant alteration of the cytoplasm as cell well as the cell membrane of these cells. Negative reaction of EMA in clear cells detected in malignant oncocytomas suggest the low grade malignant potentiality

Clinical and histological evaluation of [3-tricalcium-phosphate [cerasorb] alone or in combination with autologous platelet gel in management of osseous defects in chronic periodontitis

The purpose of the present study was to provide a clinical and histologic evaluation of b-tricalciunvphosphate [p-TCP] [cetasotb] alone 01 in combination with autologous platelet gel [APG] in management of osseous defects in chronic periodontitis A total of 16 infrabony interproximal osseous defects were chosen from 10 patients for this study. All patients were subjected to thorough clinical examination in selected sites including plaque index, gingival index, probing depth and probing attachment level. All these clinical parameters were taken prior to surgery and at 3 and 6 months post surgically. The interproximal osseous defects were divided into 2 groups, the first group comprised 8 osseous defects which were treated with full thickness mucoperiosteal flap and filled with cerasorb only. The second group comprised 8 osseous defects which were treated with cerasorb in combination with autologous platelet gel Intra oral standard periapical radiographs using long cone paralleling technique were obtained tor each defect treated in this study pre and 4 months post surgery An experimental study on 6 dogs was also included in this study, 12 surgically produced osseous defects were created in the 6 dogs. Two defects in premolar area in each dog. The defects were made similar as much as possible as regard number of osseous wall remaining depth and width. One defect was filled with cerasorb while the other was filled with cerasorb + platelet gel. 3 dogs were scarified at 2 weeks while the other 3 were scarified at 1 month. Mesio-distal sections were prepared and stained for histological examination It had been found that clinically, both treatment modalities resulted in significant improvement of probing depth and gain of attachment. Histologically, the adjunctive use of p-TCP + APG offered a more impressive regenerative potential than the use of p-TCP alone, thus it is considered to be an effective valuable mode of treatment of infrabony defects in chronic periodontitis

Overexpression of heat shock protein hsp-70 and Bcl-2 oncoprotein in oral lichen planus with malignant potentiality

Oral lichen planus [OLP] is a persistent lymphocyte mediate immunologic disorder in which basal keratinocytes appear to be the targets of T lymphocytes. In this study fifteen cases of OLP were diagnosed and assessed for both Bcl2 and HSP70 using Avidin-biotin complex [ABC] im-munohistochemical technique. The Bcl2 protooncogene is a known inhibitor of apoptosis. It is not expressed in normal stratified squamous epithelium. In cases of OLP and OLP with dysplastic changes, it shows mild reaction in sporadic cells in the suprabasal cells layer, as well as, in some lymphocytes infiltration. It is considered of cases undergoing malignant transformation and a key role in early stages of oral tumorigenesis. Heat shock proteins [HSPs] or stress proteins are expressed in the oral epithelium under physiologically normal and pathological conditions. In this respect, to assess the potential role of HSP70 in the pathogenesis of OLP, the present work is performed. In normal stratified, the expression of HSP70 is restricted to the supra-basal cell layers. Cases of OLP and OLP with dysplastic changes, revealed mild to intense positive, staining reaction in almost all layers of surface epithelium. The immunoexpression of the epithelial cells showed mainly cytoplasmic reaction of variable intensities. HSP70 expression is upregulated and showed elevated level in epithelial cells undergoing malignant transformation. Therefore it is likely to be a mrrker of malignant potential for oral epithelial cells

Expression of C-erbB2.Ki 67 and p53 in salivary gland tumors: an immunohistochemical study

Salivary gland tumors are diverse benign and malignant groups with pleomorphic adenomas as most common. The purpose of this study was to investigate the expression of apoptotic and proliferation index among cells of malignant and benign salivary gland tumors. Formalin-fixed, paraffin-embedded sections from 23 salivary gland tumors, 14 benign and 9 malignant, were studies by im-x munohistochemistry using c-erbB2, ki 67 and p53 antibodies. C-erb B2 and p53 were significantly expressed in benign and malignant tumors respectively. There was no significant difference between expression of ki 67 among benign and malignant tumors

Immunopathological study of apoptotic related factors in oral squamous cell carcinoma

Oral squamous cell carcinoma [OSCC] is considered the sixth most common malignancy , and a major cause of cancer morbidity and mortality world wide. One of the capabilities required for carcinogensis is evasion of apoptosis .This involves normal alteration in the Fas [Apo-1/ CD95] receptor ligand apoptotic pathway . Apoptosis is a physiological cell death , it plays a significant role in the pathogenesis of various diseases and tumors and also plays the main role in killing of cancer cells by chemo and radiotherapy. Twenty two cases of OSCC were studied in this research for the expression of both antigens Fas and Fas-L ligand .The correlation of their expression with the histopathological grading and with the immune escape behavior of the OSCC was the aim of this work. The correlation between the pattern of expression of Fas and the three histopathological grades of OSCC was highly significant [p< 0.004]. The apoptotic Fas receptor showed downregulation as we move to the high grade of OSCC. This results point out that it is one the of hallmark of immune escape behavior of OSCC. The altered expression of Fas antigen can be used as a marker for dys-plastic and premalignant changes. It is a prognostic factor for tumor aggressive behavior and as a predictor factor for response to chemo or radiotherapy. Primary tumors negative for the Fas-L is one of the immune escape policies of OSCC since its presence only attacks neutrophils Fas -L tumor cell expression is a late step in tumor progression and is mostly demonstrated in metastatic cases

Detection of EBV and immuno over expression of TNF alpha and C-ERB- b2 oncoproteins in giant cell grandlomas and neoplasms

Central giant cell granuloma [CGCG] is a reactive bone lesion that occurs mainly in the jaws. The giant cell tumor [GCT] is a benign locally aggressive neoplasm located near the articular end of tubular bones. Both lesions are characterized histologically by multinucleated giant cells in a back ground of ovoid to spindle shaped mesenchymal cells. Study of cell cycle associated proteins TNF a and C-erb-B[9] may give insinghts into clarifying whether both lesions are separate entities or variants of the same-disease. Also, considerable insight has been gained into EBV as an important etiologic factor in various tumors. Results demonstrate that despite the lack of EBV immunoreactivity in benign and inflammatory lesions, all the malignant tumors showed its expression in relation with the intense positivity or overexpression of C-erb-B2 . Thus, results suggest that EBV may be involved in the pathogenesis of the malignant tumors. The over expression of TNFalpha in reparative lesions as giant cell granulomas and its mild expression in malignant tumors revealed that it could be considered as an inhibitor for tumor growth through its antitumor and antiviral activities

Evaluation of absorbable collagen gel in bone fenestration and defect

This study was carried out oil six young male dogs. Following elevation of a mucoperiosteal flap, the bone and cementum were removed exposing the dentine of the canine root. A collagen gel was applied in the defect area of each dog, and the contralateral defect served as control site. The dogs were observed daily for signs of infection or graft rejection. Dogs were then sacrificed after 2, 4 and 8 weeks postoperatively. Sections of the teeth and adjacent alveolar bone were dissected immediately after scarification they were processed and escamined histologically. The Collagen gel was well tolerated with the host tissue with no adverse reactions. The untreated wound after 2, 4 and 8 weeks postperatively revealed downward epithelial migration along the root apex with more maturation of the collagen bunddles at the end of the 8 the week 8 weeks

Immunohistochemical study of some skin diseases with oral manifestations

Eleven cases of different skin diseases were investigated in the present work. These inclue 6 cases of lupus erythematosis [LE] and 2 cases of pemphigus vulgaris [PV]. These skin diseases resemble each other making their differentiation difficult. So by using clinial, histological and immunohistochemical studies attempts have been made to differentiate between these lesions and to clarify the possible viral etiologic factor. The sections were immunohistochemically stained for HPV, EBV, keratin and EMA using Avidin-Biotin peroxidase complex [ABC] method. In case of LP, intense immunoreaction to keratin throughout the epithelium was found. However, complete negative reaction was obtained with EMA, EBV and HPV. In case of LE, negative reaction to keratin was detected in the basal cell layer while a strong reaction was observed in the other epithelial layers. EMA gave mild reaction in some prickle cells. However, a strong reaction to HPV was detected. In case of PV, moderate reaction of the epithelium to keratin was detected exept the basal cell layer. A moderate reaction to EMA and HPV was found in case of PV