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PubMed1996

Clinical/biological outcomes of treatment for pericoronitis.

PURPOSE: This prospective clinical study was designed to determine the clinical and biologic outcomes of treatment for minor signs and symptoms of pericoronitis. PATIENTS AND METHODS: Patients (n = 20) with all third molars, presenting consecutively to an academic clinical center for treatment of minor signs and symptoms of pericoronitis, were enrolled in the study. At the initial visit, gingival crevicular fluid (GCF) samples to assess levels of the cytokines interleukin- 1b (IL-1b) IL-1b and prostaglandin E2 (PGE2) as a measure of the host inflammatory response, and plaque samples to identify microorganisms, were collected from the distal of all second molars and the mesial of first molars. Standardized vertical bite wing radiographs were taken to assess alveolar bone height on the distal of the second molars and the inclination and the degree of eruption of the third molar. Full-mouth periodontal probing was conducted to determine probing depths and relative clinical attachment levels (CAL). Pain levels were assessed with Gracely verbal descriptor scales for sensory intensity and unpleasantness and 10-cm visual analog scales. Symptomatic third molar sites were treated with local debridement and irrigation after baseline data collection. One week after entry, data were collected again. Subsequently, the patients were scheduled for removal of all third molars. Data collection was repeated 3 months postsurgery. As controls, data were collected from 12 subjects who had asymptomatic third molars removed previously. RESULTS: At entry, symptomatic mandibular third molars (n = 21) were mostly vertical (n = 18) and at or above the occlusal plane (n = 19). No maxillary teeth had symptoms. Microbial counts were elevated for specific anaerobic microorganisms. GCF IL-1b levels were elevated at the distal of second molars adjacent to symptomatic third molars, as compared with asymptomatic third molars and second molars in control patients. Alveolar bone levels and CAL on the distal of second molars were normal. At 1 week, patients' pain symptoms and IL-1b levels were reduced, but microbial counts remained high. Three months after surgery, patients had no pain symptoms, and alveolar bone levels and CAL were similar to entry levels. IL-1b levels were elevated at both the distal of second molars and the mesial of first molars for all patients; microbial counts decreased, although not to levels of control patients. No increase in microbial counts for Porphyromonas gingivalis or Bacteroides forsythus, or GCF PGE2 levels, risk factors for progressive periodontal disease, was detected in samples taken from the study patients. CONCLUSION: Pericoronitis expressed by minor signs/symptoms in these patients was associated with considerable discomfort. Symptomatic mandibular third molars were vertical and at or near the occlusal plane. Additionally, this condition was characterized by microbial flora and GCF inflammatory mediator levels that are more consistent with gingivitis than periodontitis. Removal of third molars eliminated symptoms, but the microbial burden and an affected patient's inflammatory response, as measured by IL-1b levels, remained elevated as compared with controls. Further study is needed to determine which of these factors can be used to identify patients at risk for pericoronitis before symptoms arise.

Adolescent↗
PubMed1978

Altered bacterial flora and clinical course with intraoral cancer.

Nineteen consecutive patients with intraoral cancer were cultured and tested for cell-mediated immunity. They were then treated and followed for three years. The recurrence rate for those patients with normal flora was similar to that reported for dinitrochlorobenzene (DNCB) reactors; and the recurrence rate for those patients with abnormal microorganisms was similar to that reported for DNCB non-reactors.

Carcinoma, Squamous Cell↗
PubMed2002

Contaminants in feed for food-producing animals.

Outbreaks of Bovine Spongiform Encephalopathy (BSE) and food borne microbial infections, dioxin contaminated animal products, the presence of veterinary drug residues, microbial resistance to antibiotics, mycotoxins, agricultural and industrial chemicals, etc. are serious concerns for the food industry in many countries. Since the direct links between feed safety and safety of foods of animal origin are obvious, feed production and manufacture should be considered as an integral part of the food production chain. Industry is responsible for the quality and safety of food and feed that is produced. This paper is a brief review of some microorganisms as source of infections for farm animals that could result in human illnesses. These include Salmonella enterica, Bacillus anthracis, Toxoplasma gondii, Trichinella spiralis, prions, Listeria monocytogenes, EHEC, Campylobacter, Clostridium botulinum, Hog Cholera virus, Foot and Mouth Disease virus, etc. as well as other contaminants associated with animal feed such as mycotoxins, veterinary drugs, dioxins and PCB and Genetically Modified Organisms.

Animal Feed↗
PubMedDate not supplied

Effects of a two-phase oil-water mouthwash on halitosis.

Many oral microorganisms possess hydrophobic outer surfaces. A two-phase, oil-water mouthwash has, therefore, recently been developed to remove such oral microorganisms. The oil phase consists of olive oil and other essential oils. The aqueous phase includes cetylpyridinium chloride, which is a disinfectant that promotes the adhesion of microorganisms to oil droplets. This study determined the effects of this mouthwash on the production of volatile sulfide in vivo and in vitro. Neither rinsing with water nor brushing teeth decreased the concentration of sulfide in mouth air at 3.5 h after treatment. A reduction of only 30% of sulfide was observed when a commercial mouthwash was used. However, this study demonstrated that use of the two-phase mouthwash led to approximately 80% reduction of sulfide. Furthermore, volatile sulfide and 2-ketobutyrate productions from methionine in a saliva putrefaction system were completely inhibited by the two-phase mouthwash; and consumption of methionine was decreased by 65 percent. It is concluded that the two-phase mouthwash strongly inhibits the production of volatile sulfide.

Adolescent↗
PubMed1988

C31G, a new agent for oral use with potent antimicrobial and antiadherence properties.

C31G, an equimolar mixture of alkyl dimethyl glycine and alkyl dimethyl amine oxide, was evaluated for antimicrobial and antiadherence properties. The efficacy of C31G, its two components, and several commercial mouth rinses was determined in assays measuring inhibition of glycolysis, inhibition of bacterial adherence, and MICs. Inhibition of glycolysis was determined by using a saliva sediment model, with glycolytic activity expressed as the change in pH relative to that of a control. Adherence studies were undertaken with Streptococcus sobrinus 6715 to measure inhibition of adherence to nichrome wires. MICs were determined against selected microorganisms by standard methods. C31G demonstrated broad-spectrum antimicrobial properties, with activity against both gram-positive and gram-negative organisms and Candida albicans, a yeast. C31G inhibited both glycolysis by salivary bacteria and adherence of Streptococcus strains to wire mesh. C31G was more effective in the assays conducted than any commercial formulation tested and was as effective as chlorhexidine. A synergistic effect was demonstrated between the individual components of C31G, and no loss of activity was noted when it was formulated into a mouth rinse vehicle.

Anti-Bacterial Agents↗
PubMedDate not supplied

Effects of solutions used in infants' oral hygiene on biofilms and oral microorganisms.

The purpose of this work was to evaluate the effects of oral hygiene solutions used for infants on biofilms formed in vitro from infants' saliva and dental plaque: ATCC reference strains A. viscosus; C. albicans; L. casei; S. mitis; S. mutans; S. oralis; S. sanguis; S. sobrinus and clinically isolated microorganisms (saliva) C. albicans, S. mitis, S. mutans, S. oralis, S. sanguis and S. sobrinus. After exposure of the oral biofilms to H2O2 diluted 1/4 to 1/16; and NaF 0.02 percent, concentrated and diluted 1/2, for 1 and 3 minutes, the viable count of microorganisms, compared to the controls was significantly reduced (p < 0.05). They also showed a significant antimicrobial effect for all the microorganisms evaluated, when compared to the control (p < 0.05). Exposure to sodium bicarbonate solution and a camomile solution, for 1 and 3 minutes, was not significantly lethal to oral biofilms nor to any microorganism evaluated, regardless of whether they were concentrated or diluted. We do not recommend the use of H2O2 but suggest using the camomile solution and NaF 0.02 percent in a rational manner for cleaning the infant's mouth.

Biofilms↗
PubMed1977

Microorganisms in recurrent aphthous ulcerations.

Qualitative and quantitative examinations of the cultivable bacterial flora in biopsies from recurrent aphthous ulcerations (RAU), experimental oral ulcerations (EOU), and normal oral mucosa (NOM) were carried out under aerobic and continuous anaerobic conditions. An attempt was made to culture yeasts, mycoplasma, and virus from the biopsies of RAU, which were also tested for the presence of herpes virus antigen by the fluorescent antibody method. The predominant bacteria recovered in RAU were alpha-hemolytic streptococci, coagulase-negative staphylococci, and Neisseria. In EOU the main recoveries were alpha-hemolytic streptococci, Corynebacterium, Veillonella, Neisseria, and Haemophilus. In NOM alpha-hemolytic streptococci dominated the cultures. Yeasts were only cultured from one patient with RAU. No mycoplasmas or viruses were isolated, nor was herpes virus antigen demonstrated in any of the RAU specimens. The role of the microorganisms in the pathogenesis of RAU is discussed.

Adolescent↗
PubMed2002

Production and characterization of an in vitro engineered human oral mucosa.

The role of epithelial cells in oral pathologies is poorly understood. Until now, most studies have used normal or transformed epithelial cell monolayers, a system that largely bypasses oral mucosal complexity. To overcome these limitations, an engineered human oral mucosa (EHOM) model has been produced and characterized. Following histological and immunohistochemical analyses, EHOM showed well-organized and stratified tissues in which epithelial cells expressed proliferating keratins such as Ki-67, K14, and K19 and also differentiating keratin (K10). In this model, epithelial cells interacted with fibroblasts in the lamina propria by secreting basement membrane proteins (laminins) and by expressing integrins (beta1 and alpha2beta1). Cytokine analyses using cultured supernatants showed that cells in EHOM were able to secrete interleukins (IL) including IL-1beta and IL-8 and tumor necrosis factor alpha (TNF-alpha). Finally, cells in this engineered model were able to secrete different metalloproteinases such as gelatinase-A and gelatinase-B. In conclusion, using tissue engineering technology, we produced well-organized EHOM tissues. It is anticipated that this model will be useful for examining mechanisms involved in oral diseases under controlled conditions by modeling the interactions between mucosa and microorganisms in the oral cavity.

Animals↗
PubMed1980

Streptococcus mutans in plaque after mouth-rinsing with buffers of varying pH value.

After a period of mouthrinsing with a phosphoric buffer solution with low pH the proportional distribution of Streptococcus mutans in plaque from occlusal retention sites was significantly higher than after a control period. This indicates that colonization with S. mutans may be favored or that other microorganisms competing with S. mutans are inhibited under these circumstances.

Buffers↗
PubMed1993

Engineered plant phosphorylase showing extraordinarily high affinity for various alpha-glucan molecules.

alpha-Glucan phosphorylases are characterized by considerable difference in substrate specificities, even though the primary structures are well conserved among the enzymes from microorganisms, plants, and animals. The higher plant phosphorylase isozyme designated as type L exhibits low affinity for a large, highly branched glucan (glycogen), presumably due to steric hindrance caused by a unique 78-residue insertion located beside the mouth of the active-site cleft, whereas another isozyme without the insertion (designated as type H) shows very high affinity for both linear and branched glucans. Using the recombinant type L isozyme from potato tuber as a starting framework and aiming at altering its substrate specificity, we have genetically engineered the 78-residue insertion and its flanking regions. Firstly, removal of the insertion and connection of the newly formed C- and N-terminals yielded a totally inactive enzyme, although the protein was produced in Escherichia coli cells in a soluble form. Secondly, a chimeric phosphorylase, in which the 78-residue insertion and its flanking regions are replaced by the corresponding region of the type H isozyme, has been shown to exhibit high affinity for branched glucans (Mori, H., Tanizawa, K., & Fukui, T., 1993, J. Biol. Chem. 268, 5574-5581), but when two and four unconserved residues in the N-terminal flanking region of the chimeric phosphorylase were mutated back to those of the type L isozyme, the resulting mutants showed significantly lowered affinity for substrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1990

Salivary conditions and cariogenic microorganisms in 55, 65, and 75-year-old Swedish individuals.

Secretion rate, buffer capacity, and cariogenic microorganisms of resting and stimulated whole saliva were examined in 208 55-, 65-, and 75-yr-old Swedes. The secretion rate for both resting and stimulated saliva decreased with age. When the use of drugs was taken into account the difference in terms of age group was significant for resting saliva alone (P less than 0.01). In 22% the resting saliva was less than 0.1 ml/min, and in 5% the stimulated saliva was less than 0.7 ml/min. Persons with subjective dryness in the mouth had a lower salivary flow. Men had higher secretion rates than women irrespective of medication (P less than 0.05). The buffer capacity was strongly correlated to the secretion rate of both resting and stimulated saliva (r = 0.39 and r = 0.44, respectively). The number of mutans streptococci and lactobacilli increased with age, although significant in terms of age group for lactobacilli alone (P less than 0.05). The number of these microorganisms was lower in resting saliva than in stimulated saliva (P less than 0.0001). Individuals harboring both Streptococcus mutans and Streptococcus sobrinus had higher values of mutans streptococci in resting and stimulated saliva than those harboring only S. mutans (P less than 0.001). Actinomyces viscosus and Actinomyces naeslundii comprised greater than or equal to 1% of the total CFU in 89% of the plaque samples. The corresponding figures for lactobacilli and mutans streptococci were 6% and 38%, respectively.

Actinomyces↗