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PubMed1994

[Halitosis (fetor ex ore). A review].

About 15% of the Dutch population has, in a more or lesser degree, complaints about bad breath. This is caused particularly by the anaerobic metabolism of a number of oral microorganisms, in which putrefaction occurs and volatile sulfur compounds will be formed. Some of these compounds are also possibly involved in the pathogenesis of periodontitis. A good oral hygiene is of primary importance to prevent halitosis and to reduce bad breath. Antiseptic mouth-waters can be helpful in the reduction of the bacterial metabolism. In addition, stimulation of the salivary secretion has a dual favourable effect, firstly because of its antimicrobial salivary proteins, and secondly by reduction of the retention of nutrients in the oral cavity.

Bacteria, Anaerobic↗
PubMedDate not supplied

[Indications and contraindications of the administration of antibiotics in oral and maxillofacial surgery].

It's well known that antibiotics are among the most widely used drugs in medicine. The administration of antibiotics in oral surgery offers a great deal, as far as the prevention of post-operative complications as well as the cure of infections diseases are concerned. Antibiotics, as all other drugs, in cases of improper use can cause harmful effects on the body. Antibiotics are used irrationally in dentistry and even more so in oral surgery for the cure of diseases which are not indicative or for the prevention of probable. As a result, there has been an increase in the frequency of their toxic side-effects plus the prevalence of resistant microorganisms. This paper describes the indications and side-effects of antibiotics in oral and maxillofacial surgery.

Anti-Bacterial Agents↗
PubMed2004

Hydroxylapatite beads as an experimental model to study the adhesion of lactic acid bacteria from the oral cavity to hard tissues.

The oral environment contains many different types of microorganisms, including both Gram-negative and Gram-positive cocci, bacilli, and spirochetes. From the ecological point of view, the oral cavity is a perfect niche for certain bacteria such as lactobacilli because they interact, forming different types of communities. Lactobacilli have been associated with the generation of caries in some reports, secondary to the cariogenic Streptococcus. In previous papers, the isolation and identification of 145 strains from healthy subjects and from subjects with active caries were performed. Strains were characterized by their surface properties and also by the production of inhibitory substances. From all the strains, one isolated from the teeth of healthy patients and another from a patient with caries, sharing some surface properties, were selected for further study of their adhesion properties in an experimental model by using hydroxylapatite beads. Adhesion is the first step in the association of microorganisms with surfaces or mucous membranes. The first approach is a nonspecific interaction of both surfaces; later some other types of interactions can occur, involving more specific mediators of adhesions. Many different assays are available to study the adhesion phenomenon; some of them use predictive characteristics, and others use experimental models resembling the in vivo situation. Two model systems predominate. The most widely used has been saliva-coated hydroxylapatite or hydroxylapatite coated with buffers, proteins, and other substances. In an attempt to increase knowledge of the mechanisms of adhesion of oral lactobacilli with hard surfaces, this chapter describes an experimental model for studing the adhesion between lactobacilli and hard tissues represented by hydroxylapatite, the component most abundant in the teeth. The following steps were performed: 1. Obtaining the microorganisms. 2. Preparation of the hydroxylapatite beads. 3. Adhesion assay.

Dental Caries↗
PubMed2003

Ludwig's angina: a clinical review.

Ludwig's angina is caused by a rapidly expanding cellulitis of the floor of the mouth and is characterized by a brawny induration of the floor and suprahyoid region (bilaterally), with an elevation of the tongue potentially obstructing the airway. In the pre-antibiotic era, Ludwig's angina was frequently fatal; however, antibiotics and aggressive surgical intervention have significantly reduced mortality. We reviewed nine patients with Ludwig's angina between July 1996 and June 2002, all of whom presented with fever, neck swelling, bilateral submandibular swelling and elevation of the tongue. In eight patients (89%) a dental infection appeared to be the underlying cause. High-dosage intravenous antibiotics directed towards the suspected causative microorganisms were given to all of the patients: two were treated successfully with conservative medical management, while seven underwent surgical drainage (a tracheotomy was necessary in one patient). Routine aerobic cultures were done on samples of drained material and the predominant microorganisms were Streptococcus species in two patients; there were none in the other five. Two patients had post-operative complications, but all recovered.

Academic Medical Centers↗
PubMed1997

Oral carriage of Helicobacter pylori: a review.

Helicobacter pylori is a microaerophilic, motile bacterium, especially adapted to life in the human stomach. The presence of H. pylori in the stomach is strongly associated with chronic gastritis and ulcer disease and is a risk factor for gastric cancers. The microorganism may be transmitted orally and has been detected in dental plaque, saliva, and feces, but the hypothesis that oral microflora may be a permanent reservoir of H. pylori is still controversial. A review of the literature suggests that the recovery of H. pylori in the mouth is probably intermittent, associated with gastroesophageal reflux but not with specific oral disease. Nonetheless, the PCR identification of oral H. pylori may become helpful, particularly in cases of gastritis or ulcer relapse after antimicrobial therapy. Eradication of oral H. pylori by local medication or periodontal procedures would rely on the precise identification of its ecological niche. Within family groups, prophylactic methods should be practiced to avoid oral carriage of H. pylori. The risk of iatrogenic transmission during dental care, however, is already circumscribed by standard professional hygiene procedures.

Carrier State↗
PubMed1997

[Clinical examination of the effect of the "Corega Junior" cleaning tablets for removable orthodontic appliances].

According to the authors' macroscopic and microbiological examinations Corega Junior prevents plaque formation on the orthodontic appliances and the establishment and multiplication of microorganisms and therefore has a favourable effect to the oral flora and last but not least to the general state of health of the patients. The usage of the Corega Junior cleaning tablets incites young people for the regular use of orthodontic appliances and indirectly for mouth care.

Adolescent↗
PubMed1975

Denture stomatitis. A histological and microradiographic study of the alveolar mucosa.

The alveolar mucosa in the upper jaw from 12 patients suffering from severe denture stomatitis was examined histologically and microradiographically using ultrasoft X-rays. Pathological changes of the epithelial cell layers were observed in all cases. In 10 of the 12 cases examined no keratinization was found. A reduction in the number of epithelial cell layers was commonly observed. In most cases the connective tissue showed signs of moderate to severe inflammation. The inflammatory reaction and the degenerative changes of the tissue were presumably due to a combined effect of microorganisms and mechanical trauma.

Alveolar Process↗
PubMed2002

[Hexetidine--an oral antiseptic].

Hexetidine is very safe oral antiseptic with broad antibacterial and antifungal activity in vivo and in vitro. It has local-anesthetics, astringent and deodorant activity. Also, it has very strong antiplac effects. Resistention of microorganisms on hexetidine is short and transient. These characteristics give important therapeutic role in treatment of oral infections.

Anti-Infective Agents, Local↗
PubMed1994

Reduction of oral microbes by a single chlorhexidine rinse.

Because of the continued threat of human immunodeficiency virus and hepatitis B infection, as well as the possibility of cross-infection from microbes, such as the herpesviruses and staphylococci, infection control remains a critical issue in dentistry. A traditional response to the infection-control issue is the use of barrier protection by the practitioner and staff. Little attention has been paid to reducing the number of potential pathogens in the oral cavity before dental procedures as a means of minimizing the potential spread of contagion between patients and treatment providers. A study to determine the effectiveness and duration of a single rinse with 0.12% chlorhexidine gluconate oral antiseptic in reducing the number of microorganisms in the oral cavity is presented.

Bacteria, Aerobic↗
PubMed2004

Genotyping of Cryptosporidium isolates from Chamelea gallina clams in Italy.

Chamelea gallina clams collected from the mouths of rivers along the Adriatic Sea (central Italy) were found to harbor Cryptosporidium parvum (genotype 2), which is the lineage involved in zoonotic transmission. The clams were collected from the mouths of rivers near whose banks ruminants are brought to graze. This paper reports the environmental spread of C. parvum in Italy and highlights the fact that genotyping of seaborne Cryptosporidium isolates is a powerful tool with which to investigate the transmission patterns and epidemiology of this microorganism.

Animals↗
PubMed1989

Arginolytic and ureolytic activities of pure cultures of human oral bacteria and their effects on the pH response of salivary sediment and dental plaque in vitro.

Thirty-nine different microorganisms commonly found in supragingival plaque and salivary sediment were screened for their ability to raise the pH by producing base from arginine, lysylarginine and urea. Only Actinomyces naeslundii and Staphylococcus epidermidis showed significant pH-rise activity with all three compounds. Eleven bacteria demonstrated such activity with arginine and lysylarginine but not with urea. Only one, Actinomyces viscosus, produced a pH-rise with urea but not with the two arginine compounds. The remaining 26 bacteria showed little or no base-forming activity with any of the three test substrates. The ability of the different oral bacteria to produce base (especially from urea) was a less universal function than their ability to produce acid from fermentable carbohydrate. Substituting pure cultures of arginolytic or non-arginolytic bacteria for portions of the mixed bacterial populations of plaque or sediment in test incubations containing glucose and arginine altered their ability to produce pH-fall-pH-rise responses shaped like those of the Stephen curve in vivo. In general, addition of arginolytic bacteria made these in vitro pH responses less acidic, whereas addition of non-arginolytic bacteria made the responses more acidic. Because of the relatively high arginolytic activity of the plaque harvested in this study, the effect of adding non-arginolytic bacteria was more readily seen than the converse. Similar changes in levels of ureolytic microorganisms and incubation with glucose and urea had little effect on sediment or plaque being able to produce a pH-fall-pH-rise type of response. When increasing proportions of the mixed bacteria in salivary sediment were replaced with the highly cariogenic Lactobacillus casei or Streptococcus mutans, the pH minimum became slightly more acidic and then slightly more alkaline, whereas the pH-rise became progressively and significantly less. Thus arginolytic bacteria have a different and greater effect on shaping the pH response of plaque or sediment than ureolytic bacteria. A large change in the proportions of arginolytic or non-arginolytic microorganisms may be needed to make a plaque microflora potentially non-cariogenic or cariogenic, respectively.

Arginine↗
PubMedDate not supplied

[Adhesion of lactic acid bacteria to epithelium of different cavities of the human organism].

During investigation of adhesive properties of lactic acid bacteria it was found out that 11 strains adhered to buccal intestinal and vaginal epithelium of human. The highest adhesive activity was detected in enterococci (adhesive index 7.75-14.26), lower one--in streptococci (6.40-9.16). In lactobacilli adhesive properties manifested in different ways: Lactobacillus acidophilus strains adhered more often to buccal epithelium (2.58-4.60) and rarely--to intestinal and vaginal. L. plantarum manifested high adhesive activity (8.03 -9.69) to buccal epithelium and lower one--to the rest of epithelium types. Monosaccharide composition of glycocalix of 6 strains of lactic acid bacteria was studied to understand the adhesion mechanism. It was shown that surface structures of this microorganism interact with plant lectins, specific to certain monosaccharides.

Bacterial Adhesion↗
PubMed1986

Scanning electron microscopic study of surface of human oral mucosa.

The surface ultrastructure of the healthy oral mucosa of humans was studied using SEM as follows: dorsum of the tongue (10 specimens), buccal mucosa (5), floor of the mouth (3), hard palate (5), and gingiva (10). One part of each formalin-fixed sample was processed routinely using the system of critical point drying for scanning electron microscopy. The other part of the specimen was embedded in paraffin blocks and stained with hematoxylin-eosin for light microscopy. With SEM at low magnification, the surface structure of the oral mucosa at different areas of the oral cavity was smooth with some desquamating cells. Only the tongue mucosa with its papillae formed a specialized mucosa. The hairs of the filiform papillae were covered by microorganisms, whereas on the oral mucosa there usually was little or no colonization by microorganisms. At high magnification, the surface structure of the superficial epithelial cells was pitted or microplicated. On keratinized epithelium the surface structure was pitted, whereas on non-keratinized epithelium it was microplicated. On cell boundaries some variation could also be seen; in keratinized epithelium these boundaries were overlapping and in non-keratinized epithelium they were tight.

Gingiva↗
PubMed1992

An analysis of the quantitative relationship between oral temperature and severity of illness in experimental shigellosis.

The relationship between oral temperature and other parameters of illness was examined in 139 adult volunteers infected experimentally with Shigella sonnei. In subjects developing clinical disease, peak temperature correlated positively with total number of signs and symptoms other than fever (rxy = .71, P < .001), stool volume (rxy = .41, P < .001) and number of stools produced during the illness (rxy = .46, P < .001). Peak temperature correlated negatively with incubation period (rxy = -.34, P = .007) but exhibited no apparent correlation with duration of illness. The average oral temperature during illness correlated positively with number of other signs and symptoms of infection but not with stool volume or stool number. These results suggest that in clinical investigations involving S. sonnei, and perhaps with other pathogenic microorganisms, oral temperature is a useful quantitative marker for estimating disease severity.

Adult↗