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J J Morrier

Publications and source records attributed to J J Morrier.

At least 19 recordsLinked to original sources
PubMed2001

Clinical usefulness of microbiological diagnostic tools in the management of periodontal disease.

Periodontal diseases comprises a group of chronic inflammatory conditions affecting tooth supporting structures. It has been known for a long time that pathogenic oral bacteria colonizing the tooth surface are associated with the initiation of the disease process. However, to date, a dozen or so bacterial species have been implicated in the pathogenesis of periodontal disease and no one species by itself is synonymous with disease onset. This multibacterial etiology renders the diagnosis of active periodontal disease based on microbiological data difficult. Numerous studies have attempted to relate the usefulness of microbiological diagnostic aids such as microscopy, bacterial culture, immunological and enzymatic assays. Furthermore, recent technical advances have resulted in the use of nucleic acid probes and amplification techniques for the identification of genetic material belonging to potential periodontal pathogens. Despite the availability of a large number of microbiological testing protocols, identification of the microbial etiological agents remains hampered by the complexity of the microbial challenge during periodontal disease. This review discusses the clinical usefulness of these tests in detection and management of periodontal disease.

Bacteria↗
PubMed2000

Effect of hydrophobicity on in vitro streptococcal adhesion to dental alloys.

Non-specific interactions such as electrostatic interactions, and surface free energy are of importance in bacterial adhesion to dental surfaces as they determine whether or not bacteria are attracted to the surface. The relationship between adherence of Streptococcus mitis, S. mutans, S. oralis and S. sanguinis on precious and non-precious dental alloys, and the bacterial and alloy surface hydrophobicities (a measure of the surface free energy) was studied. The number of adhering bacteria was determined by fluorescence microscopy counts. The hydrophobicity of the bacteria and alloy surfaces were evaluated by adhesion to hexadecane and water contact angles, respectively. Our results showed that (i) the surfaces of the tested alloys were hydrophobic, (ii) S. sanguinis, S. mutans and S. oralis were hydrophobic, and (iii) S. mitis was hydrophilic. S. oralis, the more hydrophobic strain, demonstrated the highest adherence on the tested materials, whereas S. mitis adhered least on the hydrophobic surfaces. For the tested alloys, bacterial adherence was highest for the high gold content alloy, and lowest for the non-precious alloy. Our results showed that for the tested bacterial strains, there was a significant correlation between bacterial adhesion and substratum hydrophobicity: hydrophobic metal surfaces favor adhesion of hydrophobic bacteria.

Journal Article↗
PubMed1999

Automatic enumeration of adherent streptococci or actinomyces on dental alloy by fluorescence image analysis.

The aim of the present study was to develop an automated image analysis method to quantify adherence of Streptococcus sanguinis or Actinomyces viscosus on surfaces of a currently used dental alloy. Counting such bacterial strains was difficult because of their arrangement, thus S. sanguinis being a coccus arranged in chains or pairs, and A. viscosus a long complexly arranged polymorph rod. Direct counting of fluorescently stained adherent bacteria was done visually and with image analysis methods. To differentiate these two morphotypes, two programs were developed: (i) for streptococci, thresholding and selection of the object maxima, and (ii) for actinomyces, two step thresholding and processing of the characteristic points of the object skeletons. The triplicate enumerations for each bacterial strain were not significantly different (p > 0.005) and correlations between visual counting and automated counting were significant (r = 0.91 for S. sanguinis and r = 0.99 for A. viscosus, p <00.0001). These rapid and reproducible methods, allowed us to count either cocci or rods, adherent on an inert substratum, in high density conditions.

Actinomyces viscosus↗
PubMed1998

Antimicrobial activity of amalgams, alloys and their elements and phases.

OBJECTIVES: This in vitro study aimed to evaluate the antibacterial effect of amalgams, alloys, elements and phases against two cariogenic bacteria, Actinomyces viscosus and Streptococcus mutans. METHODS: Test materials comprised: (i) commercial amalgams comprising Amalcap (Vivadent), Cavex Avalloy LC and DP (Cavex), Cupromuc (Merz), Fluoralloy and Synalloy (Dentoria); (ii) Ag-Cu alloy; (iii) gamma, gamma 1, gamma 2 and Cu6Sn5 phases; (iv) pure metal samples and chloride solutions of copper, mercury, tin and zinc; and (v) aqueous sodium fluoride. Bacterial suspensions of each of the two bacteria were grown in the presence of the test materials for 24 h. Antimicrobial effectiveness was assessed by measuring reduction in optical density at 640 nm using a visible spectrophotometer. RESULTS: Cupromuc/Fluoralloy, non gamma 2 amalgams and Amalcap displayed high, moderate and no antibacterial activity, respectively. Antibacterial effectiveness was not related to copper content. Whereas mercury, copper, Ag-Cu alloy, fluoride and zinc showed antibacterial activity (Hg > Cu > F > Zn), tin, gamma phases and Cu6Sn5 showed no such activity. SIGNIFICANCE: Although the fluoride and copper solutions were most effective at 50 micrograms ml-1 concentration, their antibacterial action was still significant, albeit reduced, at 10 micrograms ml-1 concentration. This was not the case for mercury chloride which was just as effective at both concentrations. Our results show that although mercury and copper contribute significantly to the antibacterial properties of amalgams, a high copper content does not necessarily relate to high antibacterial effectiveness. These elements could be useful in conferring antibacterial properties to amalgam although their effects on host cells must be investigated.

Actinomyces viscosus↗
PubMed1998

Interactions between non-immune host cells and the immune system during periodontal disease: role of the gingival keratinocyte.

Periodontal disease and inflammatory dermatoses, such as psoriasis, are characterized by the accumulation of dense inflammatory infiltrates immediately beneath the epithelial cell layer of the gingiva and skin, respectively. Dermatologists are increasingly aware that the epidermal keratinocyte probably contributes to inflammatory disease progression by secreting a number of pro-inflammatory cytokines and expressing various adhesion molecules. In psoriatic lesions, it is now believed that epidermal keratinocytes may also act as antigen-presenting cells and participate directly in the superantigenic activation of T-cell clones, some of which may initiate, contribute to, or maintain the disease process. Although the role of the host response in periodontal disease has been extensively studied over the years, very little is known about the contribution of the gingival keratinocyte to the inflammatory response. The available published information is discussed in this review, and we suggest that, like its epidermal counterpart, the gingival keratinocyte may participate actively in the pathogenesis of periodontal disease.

Antigen-Presenting Cells↗
PubMed1997

In vitro evaluation of the antibacterial effects of intracanal micro plasma system treatment.

Forty freshly extracted single-rooted teeth were prepared to a size 25 master apical file, autoclaved, and inoculated with a known quantity of Actinomyces naeslundii. The teeth were divided into four groups (n = 10), including an untreated control group. The three treatment groups were exposed to Micro Plasma System (MPS), 0.5% NaOCl and 0.5% NaOCl + MPS respectively. The content of each root canal was absorbed by sterile paper points, diluted in 2 ml Schaedler Broth Medium, and incubated on blood agar. The number of CFU was determined. Data analysis, using an analysis of variance and Scheffe's test at the 1% level (Statview II software), indicated a significant reduction in CFU count for the three treatment groups compared to the control group. For the three treatment groups, no significant intergroup differences were observed.

Actinomyces↗
PubMed1994

rRNA gene restriction patterns as possible taxonomic tools for the genus actinomyces.

Species delineation in the genus Actinomyces remains unclear, particularly regarding the two taxa, A. naeslundii and A. viscosus. The ribotyping patterns of 64 strains of Actinomyces, representing 8 species and comprising different serotypes, were studied as possible taxonomic tools, using an acetyl-aminofluorene (AAF)-labelled E. coli 16S + 23S rRNA probe. Similarities between patterns were assessed using Jaccard's coefficient and clustering achieved using the unweighted pair-group method with average linkage (UPGMA) on a Macintosh II (Apple, Cupertino, USA) computer. The dendrogram obtained from the ribotypes gave results which were in reasonable agreement with many previous reports: A. bovis, A. gerensceriae, A. israelii, A. meyerii, A. odontolyticus and A. pyogenes were found to be distinct species but the two taxa A. naeslundii and A. viscosus remained unclear. Further investigations, using a larger number of A. naeslundii and A. viscosus strains and other endonucleases, need to be carried out to provide more information concerning the relatedness of these two taxa. Nevertheless, these preliminary results suggested that the Actinomyces chromosome contains multiple rRNA operons which may be used as an epidemiological and taxonomical tool.

Actinomyces↗
PubMed1993

An investigation into the use of restriction endonuclease analysis for the study of transmission of Actinomyces.

DNA fingerprints of 28 reference strains of Actinomyces, comprising representatives of different species and serotypes, and 19 isolates recovered from 16 periodontal patients was performed. The aim was to determine the potential of the method for detecting strain differences in terms of discriminatory power and to evaluate its usefulness in the typing of Actinomyces strains for eco-epidemiological studies. Among the 17 restriction endonucleases tested, Bst EII, Pvu II and Sma I proved to be the most suitable for the genus Actinomyces restriction digest analysis. Visual comparisons of Bst EII, Pvu II and Sma I digest patterns of chromosomal DNA revealed clear differences within species but also within serotypes of Actinomyces that are otherwise identical. The method offers the qualities for use as an epidemiological tool for identifying sources and tracing routes of transmission of Actinomyces: stability, reproducibility, ease of preparation and interpretation and enough sensitivity for detection of differences between morphologically and serologically similar strains of Actinomyces.

Actinomyces↗
PubMed1990

[Secretary IgA and the oral cavity: general review].

The authors present a synthesis of the knowledge concerning the nature and origin of secretory IGA as well as its main components (J chain and secretory component) in the oral cavity. This IgA is the main mediator of humoral immunity and is the most frequently identified immunoglobulin in saliva. Its role in the protection of mucosae as well as in the anti-caries immunity is presented.

Dental Caries↗
PubMed1989

Antibacterial properties of five dental amalgams: an in vitro study.

The antibacterial activity of five commercially available amalgams (Cupromuc, Dispersalloy, Fluoralloy, Predalloy, and Synalloy) against two bacterial species frequently isolated from dental plaque and caries (Actinomyces viscosus and Streptococcus mutans) was studied by use of a modification of the method of Orstavik (1985). All amalgams displayed some antibacterial properties. This antibacterial activity was amalgam- and bacteria-dependent. Cupromuc and Fluoralloy were the most active, and the non-gamma 2 amalgams showed intermediate activity. Combined with mechanical and biological properties, these differences should be taken into account when one is choosing an amalgam for clinical use.

Actinomyces↗
PubMed1988

Improved SDS-Page method for protein profiles analysis of actinomyces species.

A simple, rapid SDS-Page method for protein profiles analysis of Actinomyces species was developed. Eighteen strains (12 reference strains and 6 fresh isolates) representing four species were used in this study. Eight detergents were tested for protein extraction. Cell extracts were obtained by shaking the bacteria suspended in a solution containing a detergent and glass beads. After electrophoresis, according to the Laemmli's technique, two protein stain procedure were tested (Coomassie blue and silver stain). Best results were obtained with 0.5% Triton X-100 for 4 h and the silver stain procedure of Oakley. Protein profiles analysis showed that the method is reproducible and distinguishes not only species but sometimes also subspecies.

Actinomyces↗