Abstract:
:Selected strains of oral Streptococcus and Actinomyces have been tested for their ability to grow in the presence of mercury. Strains were tested for growth on a semi-defined medium with low mercury-binding characteristics. Sensitivities were initially measured on agar plates, and subsequently, selected strains were grown in broth so that the impact of mercury on the growth characteristics could be determined. Streptococci were more resistant to mercury (5 micrograms/mL to 40 micrograms/mL) than Actinomyces (< 5 micrograms/mL to 30 micrograms/mL). The most resistant streptococci included S. mitis biovar 1, S. salivarius, S. sobrinus, and one strain of S. mutans, all of which grew on agar with 40 micrograms/mL of mercury. Two other S. mutans strains were more sensitive, being inhibited by 10 and 20 micrograms/mL mercury. The most resistant Actinomyces was A. naeslundii genospecies 1 (ATCC12104), which grew on medium with 30 micrograms/mL mercury; two strains of Actinomyces were completely inhibited by 5 micrograms/mL. Mercury caused increased lag times and reduced cell density in broth cultures. Enrichment cultures of samples of human dental plaque showed that streptococci were the most resistant organisms that could be cultured on the medium and that these strains could adapt to relatively high mercury concentrations. S. oralis and S. mitis biovar 1 were the most resistant organisms isolated from enriched cultures, growing in broth media with 65 micrograms/mL mercury. Mercury was bound to cell walls and cell cytoplasm of streptococci grown in the presence of mercury.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
J Dent Resjournal_title
Journal of dental researchauthors
Lyttle HA,Bowden GHdoi
10.1177/00220345930720091201subject
Has Abstractpub_date
1993-09-01 00:00:00pages
1325-30issue
9eissn
0022-0345issn
1544-0591journal_volume
72pub_type
杂志文章abstract::Weanling rice rats were fed either standard laboratory chow or Diet 2000. The animals were sacrificed at 4, 8, 12, and 15 weeks. There was an increasing amount of exposed root surface and root surface caries with age in the animals fed Diet 2000. There was exposed root surface but no caries in the animals fed laborato...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345770560091701
更新日期:1977-09-01 00:00:00
abstract::Previous studies have suggested that information provided by periodontal mechanoreceptors is particularly important for the fine motor control of the mandible, i.e., when humans hold and carefully manipulate food particles between the teeth with low biting forces. In the present study, we further evaluated this hypoth...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345980770041001
更新日期:1998-04-01 00:00:00
abstract::This study contains the first part of a research project in which the applicability of fracture mechanics parameters to predict failure of a restored tooth was investigated. Fracture mechanics parameters have been used in dental research before, but were restricted to comparative studies between various brands of comp...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345880670060601
更新日期:1988-06-01 00:00:00
abstract::Local anesthetic agents may be classified according to their intrinsic anesthetic potency and duration of activity. Procaine and chloroprocaine are relatively weak, short-acting drugs. Lidocaine, mepivacaine, and prilocaine represent agents of intermediate potency and duration of action. Tetracaine, bupivacaine, and e...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345810600080903
更新日期:1981-08-01 00:00:00
abstract::Stem cells from exfoliated deciduous teeth (SHED) possess multipotent differentiation and immunomodulatory properties. They have been used for orofacial bone regeneration and autoimmune disease treatment. In this study, we show that acetylsalicylic acid (ASA) treatment is able to significantly improve SHED-mediated os...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034514557672
更新日期:2015-01-01 00:00:00
abstract::The tongue plays an important role in mastication and swallowing by its contact with the hard palate. Using an experimental palatal plate with 7 pressure sensors, and recording jaw movement using mandibular kinesiography, we assessed, in healthy subjects, the coordination of tongue and jaw movements during the entire ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910608500214
更新日期:2006-02-01 00:00:00
abstract::Growing evidence suggests that individual genetic susceptibility may influence the host's response to infections. The aim of this project was to study whether gene polymorphisms of inflammatory markers are associated with the presence of viable periodontopathogenic bacteria. We extracted genomic DNA from 45 young adul...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910708600505
更新日期:2007-05-01 00:00:00
abstract::A sintered hydroxyapatite (HAP) ceramic for use in wear studies was prepared from a commercial tricalcium phosphate. The sintered HAP had physical properties close to those of human enamel. The coefficient of friction and wear of the sintered HAP ceramic as characterized by tangential force, track width, and surface f...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345780570070401
更新日期:1978-07-01 00:00:00
abstract::Zirconia-based restorations often fracture from chipping and/or delamination of the porcelain veneers. We hypothesized that veneer chipping/delamination is a result of the propagation of near-contact-induced partial cone cracks on the occlusal surface under mastication. Masticatory loading involves the opposing tooth ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910808701210
更新日期:2008-12-01 00:00:00
abstract::The purpose of the work described here was to investigate the mechanisms involved in the binding of salivary alpha-amylase to Streptococcus gordonii NCTC 7868 (Challis). Of six types of alpha-amylase studied, only mammalian forms of the enzyme were found to bind to S. gordonii cells. Salivary alpha-amylase binding was...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345900690110701
更新日期:1990-11-01 00:00:00
abstract::Vascular endothelial growth factor (VEGF) is a potent inducer of angiogenesis, vascular permeability, and edema. Up-regulation of VEGF expression in the dental pulp may result in increased intra-pulpal pressure, and contribute to pain and irreversible tissue damage. Lipoteichoic acid (LTA) is an amphiphilic molecule f...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910308200612
更新日期:2003-06-01 00:00:00
abstract::Because of the greater sensitivity of commonly used dental films near 40 kv and the inherently greater contrast between bone and other oral tissues that is achieved at lower energies than those conventionally used, a considerable reduction of radiation exposure can be obtained by the use of those quasimonochromatic ph...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345760550010801
更新日期:1976-01-01 00:00:00
abstract::Morphogenesis (germ-tube formation) in Candida albicans was induced gratuitously by N-acetylhexosamine derivatives (N-acetyl-glucosamine covalently linked to agarose, N-acetylmannosamine, hyaluronic acid, colloidal chitin, and mucin). These compounds were not taken up by the yeast cells and did not support growth. 2-D...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345840630031501
更新日期:1984-03-01 00:00:00
abstract::Thermal diffusivity, a property related to the thermal insulative efficiency of a material, was measured in nine glass-ionomer cements and compared with results from a silicate and a polycarboxylate cement. Each cement was mixed at various powder-liquid ratios (P/L) and moulded into a rectangular prism of approximate ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345870660051001
更新日期:1987-05-01 00:00:00
abstract::Odontoblasts and fibroblasts are suspected to influence the innate immune response triggered in the dental pulp by micro-organisms that progressively invade the human tooth during the caries process. To determine whether they differ in their responses to oral pathogens, we performed a systematic comparative analysis o...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910808700304
更新日期:2008-03-01 00:00:00
abstract::Using a hydraulic bellows system mounted on a maxillary partial denture, continuous force-displacement data were taken in an edentulous area in the maxillary bicuspid-molar region on ten adults. Both loading and unloading force-displacement curves showed three segments. Two visco-elastic properties - hysteresis and re...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345840630101901
更新日期:1984-10-01 00:00:00
abstract::Nearly 100% of patients experience trauma to the trigeminal nerve during orthognathic surgery, impairing sensation and sensory function on the face. In a recent randomized clinical trial, people who performed sensory re-training exercises reported less difficulty related to residual numbness and decreased lip sensitiv...
journal_title:Journal of dental research
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1177/154405910708600616
更新日期:2007-06-01 00:00:00
abstract::Dental porcelains that are designed to be fused to PFM (porcelain-fused-to-metal) alloys are formulated by their manufacturers to be closely matched in thermal expansion to these alloys. The high thermal expansion of the mineral leucite has been exploited to regulate porcelain expansion. Leucite, however, has been obs...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345000790081101
更新日期:2000-08-01 00:00:00
abstract::Glass-ionomer cements (GICs) are regarded as aqueous gels made up of polyalkenoic acid salts containing ion-leachable glass fillers. The consequence of water permeation across the GIC-dentin interface is unknown. This study used SEM, field-emission/environmental SEM (FE-ESEM), and TEM to examine the ultrastructure of ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910408300403
更新日期:2004-04-01 00:00:00
abstract::Bilateral resections of the superficial masseter, posterior temporal, and anterior digastric muscles of rats were done to determine their effects on mandibular growth. The macroscopic findings support the functional matrix theory of mandibular growth. The analysis of body weight and the statistical two-way analysis of...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345760550052301
更新日期:1976-09-01 00:00:00
abstract::Indigenous populations around the world experience a disproportionate burden in terms of oral diseases and conditions. These inequalities are likely due to a complex web of social determinants that includes poverty, historical consequences of colonialism, social exclusion, government policies of assimilation, cultural...
journal_title:Journal of dental research
pub_type: 杂志文章,评审
doi:10.1177/0022034518763605
更新日期:2018-07-01 00:00:00
abstract::Adenosine has various biological effects on human gingival fibroblasts (HGF) and epithelial cells closely associated with inflammation, such as cytokine production and cell adhesion. However, the mechanism of adenosine formation in periodontal tissues is not yet defined. In this study, we examined the involvement of C...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910308201108
更新日期:2003-11-01 00:00:00
abstract::Dental epithelial progenitor cells differentiate into various cell types during development of tooth germs. To study this mechanism, we produced immortalized dental epithelial progenitor cells derived from the cervical-loop epithelium of a rat lower incisor. The expression patterns of cytokeratin 14, nerve growth fact...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910408300209
更新日期:2004-02-01 00:00:00
abstract::Current knowledge regarding the sensitivity of the teeth to forces is based on psychophysical experiments that measured touch detection thresholds under static jaw conditions. It is not known whether jaw movements alter the perception of forces applied to the teeth, but, based on limb movement studies, it is hypothesi...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034510363101
更新日期:2010-04-01 00:00:00
abstract::The feasibility of immunizing monkeys with enzymes from oral streptococci in an attempt to reduce dental caries was investigated. Forty rhesus monkeys, Macaca mulatta, were used. Cariogenic streptococci, S mutans, were implanted into all the monkeys' mouths. There was no pathological effect resulting from immunization...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345770560123001
更新日期:1977-12-01 00:00:00
abstract::Antigenic alterations to the dentin organic matrix may be detected by an immunohistochemical approach. We hypothesized that alterations in the antigenicity of type I collagen and proteoglycans occur in sclerotic dentin under caries lesions. Transverse sections were prepared from carious teeth in the sclerotic zone and...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910608500204
更新日期:2006-02-01 00:00:00
abstract::Oxygen inhibits polymerization of resin-based materials. We hypothesized that compromised bonding to bleached enamel can be reversed with sodium ascorbate, an anti-oxidant. Sandblasted human enamel specimens were treated with distilled water (control) and 10% carbamide peroxide gel with or without further treatment wi...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910208100709
更新日期:2002-07-01 00:00:00
abstract::The effect of inflammation on the distribution of chondroitin sulfate and dermatan sulfate proteoglycans was assessed after normal and inflamed human gingivae were stained with monoclonal antibodies against these extracellular matrix macromolecules. The tissues were obtained following periodontal surgery and reacted w...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345920710090801
更新日期:1992-09-01 00:00:00
abstract::The aim of this meta-analysis, based on individual participant data from several studies, was to investigate the influence of patient-, materials-, and tooth-related variables on the survival of posterior resin composite restorations. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA...
journal_title:Journal of dental research
pub_type: 杂志文章,meta分析,评审
doi:10.1177/0022034514544217
更新日期:2014-10-01 00:00:00
abstract::In vitro wear data were determined for nine experimental composites and compared with two-year clinical data. The in vitro tests included single-pass wear and two-body abrasion. The in vivo data were obtained between 1978 and 1980 for 54 class 2 posterior composite restorations in 25 patients. Correlations between the...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345830620101801
更新日期:1983-10-01 00:00:00