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PubMed1992

Management of oral health in persons with HIV infection.

Prevention and treatment of oral disease is required to maintain quality of life and to improve prognosis of patients infected with the human immunodeficiency virus (HIV). Management requires a team approach, and close collaboration with the appropriate responsible physicians and other health care workers is necessary. Oral infection is frequent and usually opportunistic, and management is based on certain principles. Infections may disseminate and can be persistent and severe; multiple concurrent or consecutive infections with different microorganisms are frequent; fungal, viral, and parasitic infections are rarely curable; and long-term antimicrobial therapy may be required. This article reviews the management of oral candidiasis, hairy leukoplakia, and infections with herpes simplex virus, varicella-zoster virus, and cytomegalovirus. The management of Kaposi's sarcoma, lymphomas, aphthous ulceration, gangrenous stomatitis, bleeding, xerostomia, and adverse drug reactions is also described. Treatment should avoid further immunosuppression and inducement of xerostomia or caries, and should be designed to avoid adverse drug reactions and possible drug interactions.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Quantitative analysis of multi-species oral biofilms by TaqMan Real-Time PCR.

Oral infectious diseases, including dental caries, various forms of periodontitis and oral malodor, are not caused by a single pathogen. The etiology of these diseases is known to be associated with bacterial accumulation and plaque composition on the hard and soft tissues of the oral cavity. Therefore, the quantitative, as well as qualitative, analysis of the microorganisms present in oral biofilms, namely dental plaque, subgingival plaque and tongue debris, is important for diagnosis and rational treatment decisions. The quantitative microbial analysis of oral multi-species biofilms also provides useful information for establishing the etiology of oral infectious diseases. Recently, a 5' fluorogenic, nuclease-based, real-time polymerase chain reaction (PCR) technique has been increasingly employed for the quantitative microbial assessment of the human oral cavity. We review the development and use of TaqMan real-time PCR for quantifying oral bacteria, its role in the diagnosis of oral infectious diseases and their microbial etiology.

Bacteria↗
PubMed1998

Antimicrobial activity of propolis on oral microorganisms.

Formation of dental caries is caused by the colonization and accumulation of oral microorganisms and extracellular polysaccharides that are synthesized from sucrose by glucosyltransferase of Streptococcus mutans. The production of glucosyltransferase from oral microorganisms was attempted, and it was found that Streptococcus mutans produced highest activity of the enzyme. Ethanolic extracts of propolis (EEP) were examined whether EEP inhibit the enzyme activity and growth of the bacteria or not. All EEP from various regions in Brazil inhibited both glucosyltransferase activity and growth of S. mutans, but one of the propolis from Rio Grande do Sul (RS2) demonstrated the highest inhibition of the enzyme activity and growth of the bacteria. It was also found that propolis (RS2) contained the highest concentrations of pinocembrin and galangin.

Actinomyces↗
PubMed1992

The role of oral microorganisms in cancer therapy.

It has been assumed that the principal changes that occur in the oral flora during cancer therapy are yeast and gram-positive coccal proliferation. Recent studies have shown that treatment with topical antifungals or disinfectants has failed to relieve such complications as irradiation mucositis that occur during anticancer therapy. Thus, many of the oral lesions observed during treatment are not due to candidiasis or streptococcal infection. It has been shown that anticancer therapy impairs or reduces the carriage defense of the oropharynx and is accompanied by colonization and proliferation of gram-negative bacilli. It is argued that if oral infectious complications are to be prevented during anticancer therapy, then the selective elimination of gram-negative bacilli may be indicated.

Antineoplastic Agents↗
PubMed1998

[Determination of the dispersion of microorganisms in the course of dental surgical activity].

The professionals and patients involved in dental examinations are at risk for infection by various disease-causing bacteria, viruses, and fungi, such as those responsible for hepatitis, tuberculosis, herpes, and AIDS. It is known that aerosols and spatter containing pathogenic microorganisms can spread during an examination. Nevertheless, some dental clinics are designed to have multiple examination areas in the same room, with no physical barriers between them. The objective of this study was to verify the reach of spatter resulting from the use of a triple syringe and high-rotation turbine during five simulated exams in a collective clinic, bearing in mind that spatter can contain the patient's saliva and blood. To facilitate tracking of the spatter, aniline dye (pink, blue, yellow, green, and brown) was added to the water in the appropriate receptacle in each of the five units. The room, the equipment, and the patient's and operator's clothing were covered with white paper. A high concentration of spatter was observed on the chair, the operator, and the floor of each unit, and it also appeared on the chairs and trays of the surrounding units. The maximum distance reached by spatter was 1.82 m from a point on the chair corresponding to the position of the patient's mouth. During real simultaneous examinations, the surrounding chairs and their patients and operators, as well as the trays containing sterilized instruments, are within spatter range. Therefore, there is a real possibility of cross-infection, and physical barriers should be placed between the units. This study also confirmed the need for protection of the operator's face, body, hair, and arms, since these regions were heavily affected by spatter.

Air Microbiology↗
PubMed1978

The in vitro inhibition of microbial growth and plaque formation by surfactant drugs.

Several cationic, mixed and amphoteric surfactants were tested for their antimicrobial activity and ability to inhibit the formation of in vitro plaque by oral microorganisms. All had antimicrobial activity against Actinomyces viscosus. Actinomyces naeslundii and Streptococcus mutans. Cationic surfactants were comparable to chlorhexidine in antimicrobial activity but were less effective in inhibiting plaque formation. Amphoteric surfactants were less effective than other detergents in antibacterial activity and had very limited capacity for the inhibition of plaque formation. Comparison of drug structure provides evidence that surfactant substantivity to saliva-coated enamel is a cation active process. Saliva was found to have an antagonistic effect on the activity of cetylpyridinium chloride but not on Triburon.

Actinomyces↗
PubMed1985

Treatment of orofacial infections of odontogenic origin.

Acute purulent orofacial infections are often of odontogenic origin. The microorganisms and the anatomical site involved, largely determine the clinical manifestations. The infections are usually self-limiting but serious complications may ensue. Direct invasion of different anatomical spaces may cause mediastinitis, airway obstruction and also intracranial spread. Anaerobic bacteria belonging to the normal oropharyngeal flora (anaerobic cocci, bacteroides and fusobacteria) are usually isolated from orofacial abscesses. Surgical treatment including incision and drainage is essential. The drug of choice for antimicrobial therapy is penicillin. Penicillin resistant anaerobic bacteria may however make penicillin ineffective and antimicrobial agents such as metronidazole or clindamycin are then recommended to be used.

Anti-Bacterial Agents↗
PubMed2003

Fluoride and organic weak acids as modulators of microbial physiology.

Fluoride is widely used as an anticaries agent in drinking water and a variety of other vehicles. This use has resulted in major health benefits. However, there are still open questions regarding the mechanisms of anticaries action and the importance of antimicrobial effects in caries reduction. Fluoride acts in multiple ways to affect the metabolism of cariogenic and other bacteria in the mouth. F(-)/HF can bind directly to many enzymes, for example, heme-containing enzymes or other metalloenzymes, to modulate metabolism. Fluoride is able also to form complexes with metals such as aluminum or beryllium, and the complexes, notably AlF(4)(-) and BeF(3)(-).H(2)O, can mimic phosphate with either positive or negative effects on a variety of enzymes and regulatory phosphatases. The fluoride action that appears to be most important for glycolytic inhibition at low pH in dental plaque bacteria derives from its weak-acid properties (pK(a)=3.15) and the capacity of HF to act as a transmembrane proton conductor. Since many of the actions of fluoride are related to its weak-acid character, it is reasonable to compare fluoride action to those of organic weak acids, including metabolic acids, food preservatives, non-steroidal anti-inflammatory agents and fatty acids, all of which act to de-energize the cell membrane by discharging DeltapH. Moreover, with the realization that the biofilm state is the common lifestyle for most microorganisms in nature, there is need to consider interactions of fluoride and organic weak acids with biofilm communities. Hopefully, this review will stimulate interest in the antimicrobial effects of fluoride or other weak acids and lead to more effective use of the agents for disease control and other applications.

Acids↗
PubMed1993

[Selective gut decontamination in ventilated intensive therapy patients].

Treatment of long-term artificially ventilated patients is often complicated by nosocomial infections. The infection that occurs with the highest frequency during intensive care treatment is pneumonia (22-63%). Ninety per cent of nosocomial infections of intensive care patients are endogenous infections caused by mainly gram-negative aerobic microorganisms that have colonized in the gastrointestinal tract. Selective decontamination of the intestine provides a method that prevents nosocomial infections. In a prospective study 13 patients whose oropharynx and gastrointestinal tract had been decontaminated (SDD) were compared to 17 patients in a control group. In a third group twelve patients were decontaminated in the gastrointestinal tract (SGD) only, and in a fourth group 16 patients were decontaminated in the oropharynx (SMD) only. Trachea, oropharynx and faeces of the patients belonging to the control group (KG) were colonized to almost 100% with gram-negative bacteria. Only 10% of the patients of the SDD and SMD groups showed gram-negative bacteria located in the trachea and oropharynx after one week of decontamination. No gram-negative aerobic bacteria were present after seven days in the faeces of the patients of the SDD and SGD groups. There was no difference with regard to the trachea and oropharynx between the control group and the SGD group. The gram-negative aerobic intestinal flora was not affected by the selective mouth decontamination. The average rate of pneumonia occurrence within the 15-day observation period was 28.2% for the control group, 14% for the SGD group, and 9.6% for the SDD group, and 4.1% for the SMD group. Decontamination of the oropharynx of patients is essential in order to successfully prevent pneumonia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1982

Humoral immune response to oral microorganisms in periodontitis.

Serum antibody titers from patients with periodontitis were compared with those from periodontally healthy subjects. With the micro-enzyme-linked immunosorbent assay, immunoglobulin G (IgG), IgA, and IgM antibody titers to isolates of Streptococcus sanguis, Actinomyces viscosus, Bacteroides gingivalis, Bacteroides melaninogenicus subsp. intermedius, Bacteroides gingivalis, Bacteroides melaninogenicus subsp. intermedius, Bacteroides ochraceus, and Fusobacterium nucleation were determined. Antibody titers of the IgG and IgA classes to B. melaninogenicus, B. ochraceus, F. nucleatum, and S. sanguis were found to be significantly higher in the controls than in the patients. No correlations were found with serum IgM titers. These findings indicate that periodonitis may be associated with depressed antibacterial serum antibody titers of the IgG and IgA classes.

Adult↗
PubMed1991

Antibacterial activity of crotalid venoms against oral snake flora and other clinical bacteria.

Despite heavy oral and fang contamination of crotalid species with a wide variety of potentially pathogenic bacteria, crotalid envenomation is associated with a low incidence of bacterial infection. Minimal inhibitory and bactericidal concentrations of venoms from three crotalid species were determined against six aerobic and eight anaerobic reference and oral crotalid microorganisms. All anaerobic isolates were resistant to greater than 20,480 micrograms/ml, whereas variable activity (range, 5-20,480 micrograms/ml) was observed for aerobic strains. Further studies against other aerobic clinical isolates demonstrated that venom had the greatest activity (MIC, less than or equal to 80 micrograms/ml) against staphylococci, Pseudomonas aeruginosa, and Enterobacter, Citrobacter, Proteus, and Morganella species. Inhibitory activity was lost with prolonged incubation for many gram-negative species. Crotalid venoms are broadly active against aerobic gram-negative and -positive bacteria. This activity may play a role in the low incidence of infection after envenomation injuries.

Animals↗
PubMed1998

Oral microbiota and implant type membranes.

Candida albicans (Ca), Staphylococcus aureus (Sa), Streptococcus sanguis (Ss), Actinomyces naeslundii (An), Actinomyces odontolyticus (Ao), Porphyromona spp (P spp), Candida glabrata (Cg), Candida krusei (Ck), and Rhodotorula spp (R spp) were tested with equal pieces of biodegradable membranes. Membranes pretreated with saliva or clorhexidine and nontreated control membranes were tested in three different culture media containing 0.1 mL homologous suspension for each strain under study. Incubation was performed at 37 degrees C for 48 hours for aerobiosis and for five days for anaerobiosis. Macroscopy and microscopy were carried out. Membranes were removed, washed, and resuspended. Samples were sonicated, and the supernatant was disseminated on brain heart infusion broth or blood agar. Incubation was repeated, colony-forming unit counts were performed, and statistical analysis was carried out using analysis of variance transforming results to Log10 (x + 1), the highest interaction level was used to calculate standard error. Orthogonal contrast was used to compare the different microorganisms under study. Highest adhesion was found with Ca, Cg, Ck, Sa, and Ss. A sufficient quantity of Actinomyces could not be recovered from the membranes. Results with P spp were poor, confirming lower gram-negative adhesion. Replicate flasks with Ss and Ca were cultivated. Membranes were removed after washing and subjected to scanning electron microscopy, as were untreated control pieces. A cavelike surface was observed. Streptococcus sanguis adhering to the membranes showed extracellular projections. Candida and gram-positive cocci showed great recovery capacity.

Actinomyces↗
PubMed1977

Dental aspects of patients with cystic fibrosis: a preliminary clinical study.

The oral conditions of 42 patients being treated for cystic fibrosis were evaluated. The patients were grouped by age and, in some aspects, were compared with a small control group of their siblings. The patient group had a lowered incidence of plaque and less gingival disease than did the control group in which every person had some amount of plaque or gingival disease. Calculus formation was minimal. The reasons for the finding of minimal plaque in the patient group could be related to several factors, including the life-long use of various antibiotic agents, the chewing of digestive enzyme supplements, the effect of medical management on tooth hardness, and the effect of stained teeth (possible tetracycline deposition) on the plaque microorganisms. It appears that the therapy for cystic fibrosis was beneficial to the periodontal health of these patients. Much further study is needed to understand the interrelationship between an altered oral environment (salivary changes in cystic fibrosis), altered microbial flora (by antibiotics, enzymes) and even altered tooth surfaces (possible tetracycline deposition). Most patients were found to have one or more oral habits. Tooth mobility was associated with tension habits. Patients who had clubbed fingers (indicating pulmonary compromise) and possibly a severe disease process, did not appear to have either stained teeth or the severity of the gingivitis associated with this. The relationship of tetracycline to tooth staining could not be pinpointed.

Cystic Fibrosis↗
PubMed2001

Adrenomedullin expression in pathogen-challenged oral epithelial cells.

Adrenomedullin, a multifunctional peptide, is expressed by many surface epithelial cells and, previously, we have demonstrated that adrenomedullin has antimicrobial activity. The oral cavity contains an epithelium that is permanently colonized by microflora, yet infections in a host are rare. We exposed oral keratinocytes to whole, live cells from four microorganisms commonly isolated from the oral cavity, Porphyromonas gingivalis, Streptococcus mutans, Candida albicans and Eikenella corrodens. There was upregulation of protein and gene expression in these cells in response to bacterial suspensions, but not with the yeast, Candida albicans. We propose there is a potential role for microbial products in enhancing mucosal defense mechanisms and that adrenomedullin participates in the prevention of local infection, thus contributing to host defense mechanisms.

Adrenomedullin↗
PubMed2004

Nutrition and oral health in Africa.

Poverty, low birth weight, low life expectation at birth, widespread malnutrition, numerous endemic infections, little or no access to safe water, poor oral hygiene, deplorable environmental sanitation and political instability among other problems, characterise the lives of many Africans, particularly in sub-Saharan Africa. In African countries undergoing rapid urbanisation, health problems associated with undernutrition and overnutrition coexist, and these result from lifestyle changes which promote physical inactivity, increased consumption of fats and refined carbohydrates, as well as abuse of tobacco and alcohol. Thus, in several African countries, inflammatory oral diseases (e.g. periodontal diseases, acute necrotising gingivitis, noma) resulting from inappropriate interactions between microorganisms and the malnourished, immunocompromised host, have continued to pose serious health problems. There are suggestions of increasing incidence of squamous cell carcinoma, probably related to increased use of alcohol and tobacco, which elicit nutrient deficiencies and oxidative stress. Additionally, there is an increase in caries prevalence particularly in the poor urban areas. The latter is related not only to increased availability of refined sugars, but also to limited access to the caries preventive effects of fluorides. Good dietary practices through judicious combination of available foods should therefore feature prominently in the promotion of optimal oral health in Africa.

Africa↗
PubMed1996

The effect of areca nut on salivary and selected oral microorganisms.

The aim of this study was to investigate the effect on the growth of salivary and selected oral microorganisms of areca nut, aqueous extracts of the nut, its major alkaloid arecoline and the components tannic acid and catechin of its tannin fraction. The antibacterial properties of the above were tested on Streptococcus mutans, Streptococcus salivarius, Candida albicans and Fusobacterium nucleatum and, as a control, Staphylococcus aureus. This was followed by investigating its effect on salivary organisms cultured from the saliva after chewing boiled areca nut. Extracts inhibited the growth of the selected organisms in a concentration dependent manner, baked and boiled nuts being significantly more potent than raw nut. Growth of C. albicans was the least affected by the nut extracts. Tannic acid was strongly antibacterial but not catechin or arecoline. No antibacterial effect could be demonstrated on salivary organisms after chewing the nut for 5 minutes but exposure of saliva to the cud for 1 hour caused a significant depression of bacterial growth. It is concluded that the hydrolysable tannins in the tannin fraction, which include tannic acid, are responsible for the antibacterial properties of the nut and that prolonged intraoral exposure to the nut can suppress bacteria in the mouth.

Analysis of Variance↗
PubMed1986

Effects of chlorhexidine gluconate in drinking water on dental caries and oral microorganisms in the Syrian hamster.

Hamsters infected with Streptococcus sobrinus (formerly Streptococcus mutans) strain 6715-1119 were given high-sucrose diet 2000. After 5 days, they were presented with 0.05 or 0.1 per cent w/v chlorhexidine gluconate (CHX) continuously in their drinking water, which was well-tolerated. Compared to infected but untreated controls, their caries scores were less by 84 and 97 per cent respectively after 42 days. Coronal dental plaque deposits were reduced in a dose-related fashion. Culture plates of oral swabs showed reductions in Strep. sobrinus and total streptococci after 10 and 35 days of CHX. Hamster oral streptococci were more sensitive to CHX than were lactobacilli but neither was completely eliminated. The incidence of stained tooth deposits after 0.1 per cent CHX was slightly but not significantly greater than in controls.

Animals↗
PubMed1992

Biochemical and clinical factors influencing oral malodor in periodontal patients.

The amounts of volatile sulfur compounds (VSC) and methyl mercaptan/hydrogen sulfide ratio in mouth air from patients with periodontal involvement were 8 times greater than those of control subjects. Our studies demonstrated that, in patients with periodontal disease: 1) the concentration of disulfide, which is converted to VSC, increased in proportion to the total pocket depth; 2) 60% of the VSC was produced from the tongue surface; 3) the amount of tongue coating was 4 times greater than in control subjects; and 4) VSC production and the methyl mercaptan/hydrogen sulfide ratio of the tongue coating were increased. 2-Ketobutyrate, which is a byproduct of the metabolism of methionine to methyl mercaptan, was higher in the saliva of patients with periodontal disease. This implies that metabolism of methionine to methyl mercaptan increases in the oral cavity of patients with periodontal pockets. Since free L-methionine, rather than protein, is the main source for methyl mercaptan, we estimated the methionine supply from the gingival fluid into the oral cavity of patients with periodontal involvement. The results showed that the ratio of methionine to whole free amino acids was significantly higher than that of cysteine. Our studies suggest that not only microorganisms, but also the tongue coating and gingival fluid are factors which enhance VSC production in patients with periodontal disease.

Halitosis↗