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1.
Georgian Med News ; (298): 67-70, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32141852

RESUMEN

Although the pathogenesis of periodontal lesions has not been sufficiently studied, recent studies show that plaque formation and host immune response are important factors. The purpose of this study was improving efficiency of plaque-induced gingivitis treatment in children with immunological correction of saliva by administration of polyvitamins and lysozyme tablets. We have examined 60 12-year-old children diagnosed with plaque-induced gingivitis and divided them into the main and control groups consisted of 30 children in each accordingly. The children of both groups were treated by sanitation and professional oral hygiene. The children of the main group besides were prescribed with multivitamins complex "Supervit" and tablets "Lizak". The efficiency of the introduced complex we have assessed by contain of immunoglobulins A (IgA), immunoglobulins G (IgG), secretory immunoglobulin A (s-IgA), interleukin 1ß (IL-1ß), interleukin 4 (IL-4) and lysozyme in saliva. After 6 month the treatment children from the main group showed a decline in concentration of IL-1ß by 30,06 % (р<0,01), IgA by 33,34 %, IgG by 12,5 % (р<0,05). The present data support the high efficiency of the introduced treatment that has been proved by positive progress of immunological indexes in saliva taken within six and 12 month since the research.


Asunto(s)
Placa Dental/metabolismo , Gingivitis/tratamiento farmacológico , Muramidasa/administración & dosificación , Saliva/química , Vitaminas/administración & dosificación , Niño , Femenino , Gingivitis/inducido químicamente , Gingivitis/inmunología , Humanos , Inmunoglobulina A Secretora/análisis , Masculino , Saliva/inmunología , Comprimidos , Resultado del Tratamiento
2.
Appl Environ Microbiol ; 85(10)2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-30877119

RESUMEN

N-Acetylglucosamine (GlcNAc) and glucosamine (GlcN) enhance the competitiveness of the laboratory strain DL1 of Streptococcus gordonii against the caries pathogen Streptococcus mutans Here, we examine how amino sugars affect the interaction of five low-passage-number clinical isolates of abundant commensal streptococci with S. mutans by utilizing a dual-species biofilm model. Compared to that for glucose, growth on GlcN or GlcNAc significantly reduced the viability of S. mutans in cocultures with most commensals, shifting the proportions of species. Consistent with these results, production of H2O2 was increased in most commensals when growing on amino sugars, and inhibition of S. mutans by Streptococcus cristatus, Streptococcus oralis, or S. gordonii was enhanced by amino sugars on agar plates. All commensals except S. oralis had higher arginine deiminase activities when grown on GlcN and, in some cases, GlcNAc. In ex vivo biofilms formed using pooled cell-containing saliva (CCS), the proportions of S. mutans were drastically diminished when GlcNAc was the primary carbohydrate. Increased production of H2O2 could account in large part for the inhibitory effects of CCS biofilms. Surprisingly, amino sugars appeared to improve mutacin production by S. mutans on agar plates, suggesting that the commensals have mechanisms to actively subvert antagonism by S. mutans in cocultures. Collectively, these findings demonstrate that amino sugars can enhance the beneficial properties of low-passage-number commensal oral streptococci and highlight their potential for moderating the cariogenicity of oral biofilms.IMPORTANCE Dental caries is driven by dysbiosis of oral biofilms in which dominance by acid-producing and acid-tolerant bacteria results in loss of tooth mineral. Our previous work demonstrated the beneficial effects of amino sugars GlcNAc and GlcN in promoting the antagonistic properties of a health-associated oral bacterium, Streptococcus gordonii, in competition with the major caries pathogen Streptococcus mutans Here, we investigated 5 low-passage-number clinical isolates of the most common streptococcal species to establish how amino sugars may influence the ecology and virulence of oral biofilms. Using multiple in vitro models, including a human saliva-derived microcosm biofilm, experiments showed significant enhancement by at least one amino sugar in the ability of most of these bacteria to suppress the caries pathogen. Therefore, our findings demonstrated the mechanism of action by which amino sugars may affect human oral biofilms to promote health.


Asunto(s)
Amino Azúcares/metabolismo , Caries Dental/metabolismo , Placa Dental/metabolismo , Infecciones Estreptocócicas/metabolismo , Streptococcus gordonii/fisiología , Streptococcus mutans/fisiología , Simbiosis , Biopelículas/crecimiento & desarrollo , Saliva/microbiología
3.
Clin Oral Investig ; 23(9): 3527-3534, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30543027

RESUMEN

OBJECTIVES: Regulation of lipopolysaccharide (LPS) chemical composition, particularly its lipid A domain, is an important, naturally occurring mechanism that drives bacteria-host immune system interactions into either a symbiotic or pathogenic relationship. Members of the subgingival oral microbiota can critically modulate host immuno-inflammatory responses by synthesizing different LPS isoforms. The objectives of this study were to analyze subgingival lipid A profiles and endotoxin activities in periodontal health and disease and to evaluate the use of the recombinant factor C assay as a new, lipid A-based biosensor for personalized, point-of-care periodontal therapy. MATERIALS AND METHODS: Subgingival plaque samples were collected from healthy individuals and chronic periodontitis patients before and after periodontal therapy. Chemical composition of subgingival lipid A moieties was determined by ESI-Mass Spectrometry. Endotoxin activity of subgingival LPS extracts was assessed using the recombinant factor C assay, and their inflammatory potential was examined in THP-1-derived macrophages by measuring TNF-α and IL-8 production. RESULTS: Characteristic lipid A molecular signatures, corresponding to over-acylated, bi-phosphorylated lipid A isoforms, were observed in diseased samples. Healthy and post-treatment samples were characterized by lower m/z peaks, related to under-acylated, hypo-phosphorylated lipid A structures. Endotoxin activity levels and inflammatory potentials of subgingival LPS extracts from periodontitis patients were significantly higher compared to healthy and post-treatment samples. CONCLUSIONS: This is the first study to consider structure-function-clinical implications of different lipid A isoforms present in the subgingival niche and sheds new light on molecular pathogenic mechanisms of subgingival biofilm communities. CLINICAL RELEVANCE: Subgingival endotoxin activity (determined by lipid A chemical composition) could be a reliable, bacterially derived biomarker and a risk assessment tool for personalized periodontal care.


Asunto(s)
Periodontitis Crónica , Placa Dental , Endotoxinas , Microbiota , Periodontitis , Bacterias , Placa Dental/metabolismo , Placa Dental/microbiología , Endotoxinas/metabolismo , Humanos , Lípido A/metabolismo , Periodontitis/metabolismo , Periodontitis/microbiología
4.
BMC Oral Health ; 19(1): 246, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31722703

RESUMEN

BACKGROUND: The extent to which the composition and diversity of the oral microbiome varies with age is not clearly understood. METHODS: The 16S rRNA gene of subgingival plaque in 1219 women, aged 53-81 years, was sequenced and its taxonomy annotated against the Human Oral Microbiome Database (v.14.5). Composition of the subgingival microbiome was described in terms of centered log(2)-ratio (CLR) transformed OTU values, relative abundance, and prevalence. Correlations between microbiota abundance and age were evelauted using Pearson Product Moment correlations. P-values were corrected for multiple testing using the Bonferroni method. RESULTS: Of the 267 species identified overall, Veillonella dispar was the most abundant bacteria when described by CLR OTU (mean 8.3) or relative abundance (mean 8.9%); whereas Streptococcus oralis, Veillonella dispar and Veillonella parvula were most prevalent (100%, all) when described as being present at any amount. Linear correlations between age and several CLR OTUs (Pearson r = - 0.18 to 0.18), of which 82 (31%) achieved statistical significance (P < 0.05). The correlations lost significance following Bonferroni correction. Twelve species that differed across age groups (each corrected P < 0.05); 5 (42%) were higher in women ages 50-59 compared to ≥70 (corrected P < 0.05), and 7 (48%) were higher in women 70 years and older. CONCLUSIONS: We identified associations between several bacterial species and age across the age range of postmenopausal women studied. Understanding the functions of these bacteria could identify intervention targets to enhance oral health in later life.


Asunto(s)
Placa Dental , Microbiota , Posmenopausia , Anciano , Anciano de 80 o más Años , Bacterias , Placa Dental/metabolismo , Femenino , Humanos , Microbiota/genética , Persona de Mediana Edad , ARN Ribosómico 16S
5.
Wiad Lek ; 71(2 pt 2): 378-382, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29786589

RESUMEN

OBJECTIVE: Introduction: According to the 2003 WHO report, dental caries affects from 60% to 90% of school-age children and adults that makes it one of the most common diseases worldwide. The aim was to systematize data about the modern conception of plaque formation and role of microorganisms in its development. PATIENTS AND METHODS: Materials and methods: Biblosemantic, 50 medical literature sources were systematically reviewed as the material for the research. RESULTS: Review: According to Miller's theory, oral microorganisms can decompose dietary carbohydrates into acids, which in turn dissolve the calcium phosphates found in the enamel, causing it demineralisation Along with Streptococcus mutans, nowadays some other bacteria as Streptococcus sorbinus, Lactobacillus spp. and Actinomyces spp. have been well studied as caries contributors. However, the disease is related to plaque-mediated, because a much larger number of normal oral microflora representatives are involved in creating favourable preconditions for its development. There are a lot of original research papers about a role of bacteria in caries decay but compositions and characters of oral microflora are changing nowadays. Therefore, authors show the main cariogenic bacteria and their factors of pathogenicity which create special conditions for caries lesions. Modern concepts of dental plaque formation and pathogenesis of plaque-assosiative diseases are presented according to the new actual dental research. A lot of attention is paid to the biochemical properties of cariogenic bacteria and chemical process in biofilm. Role of acid and alkali production by oral bacteria in caries decay are shown in this article. Moreover, mechanisms of bacterial acid-fast and acid-tolerance are presented. CONCLUSION: Conclusions: Analysis of literature demonstrates a lot of bacterial pathogenicity factors which play key role in caries development.


Asunto(s)
Cariogénicos/efectos adversos , Caries Dental/metabolismo , Placa Dental/metabolismo , Dieta Cariógena/efectos adversos , Carbohidratos de la Dieta/efectos adversos , Desmineralización Dental/metabolismo , Cariogénicos/metabolismo , Niño , Humanos , Concentración de Iones de Hidrógeno
6.
Oral Health Prev Dent ; 15(2): 153-156, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28322358

RESUMEN

PURPOSE: To assess the inhibitory effects of nitrite on plaque acidogenicity and its relationship with caries experience. MATERIALS AND METHODS: Plaque (2 µl) was collected from 76 children (age 5.8 ± 2.6 years, dmft 2.9 ± 3.5, DMTF 0.6 ± 1.4) and mixed with nitrite solution (final concentration = 0.63 mM) or distilled water (control). The initial pH (pH-0) of each sample was measured using a portable pH meter. The samples were incubated for 10 min, then their pH (pH-1) was measured again. Next, glucose (final concentration = 0.67%) was added to the samples, which were then incubated for a further 10 min before their pH was assessed for a third time (pH-2). RESULTS: The pH-0, pH-1, and pH-2 values of the control samples were 7.25 ± 0.16, 6.07 ± 0.44, and 5.11 ± 0.48, respectively, and those of the nitrite-treated samples were 7.26 ± 0.16, 6.37 ± 0.45, and 5.34 ± 0.48, respectively. The pH-1 and pH-2 values of the nitrite-treated samples were higher than those of the control samples (p < 0.005). Greater plaque acid production was associated with stronger inhibition of plaque acid production by nitrite (p < 0.005). No relationship was detected between the inhibition by nitrite and caries experience. CONCLUSIONS: Nitrite inhibited both endogenous and exogenous plaque acid production. Nitrite inhibited acid production more markedly in plaque that exhibited greater acid production, suggesting that nitrite might be effective at preventing caries, as it contributes to pH homeostasis in plaque by countering excess acidification.


Asunto(s)
Ácidos/antagonistas & inhibidores , Placa Dental/metabolismo , Nitritos/farmacología , Niño , Preescolar , Caries Dental/metabolismo , Humanos
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(4): 491-494, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-28591948

RESUMEN

OBJECTIVES: To determine the role of high mobility group chromosomal protein N2 (HMGN2) in the development of periodontitis plaque biofilm. METHODS: Saliva samples were collected before clinical interventions in patients with periodontitis (25 Mild periodontitis, 25 Moderate periodontitis and 25 Severe periodontitis) and healthy controls ( n=25).Following an estimation of dental plaque index, the level of HMGN2 in saliva was determined by enzyme-linked immunosorbent assay (ELISA).The recombinant human HMGN2 protein was purified and tested, its inhibitive effects on Porphyromonas gingivalis (P.g)growth and formation of P.g bioflim were detected by K-B antibacterial annulus and crystal violet staining, respectively. RESULTS: The healthy controls had lower levels of HMGN2 in saliva than those with periodontitis, especially those with severe periodontitis ( P<0.01).The level of HMGN2 was negatively correlated with dental plaque index ( r=-0.363, P<0.05). HMGN2 inhibited the development of main periodontal bacteria biofilm ( P<0.05). CONCLUSIONS: HMGN2 is involved in the development of periodontitis plaque biofilm and plays an important role in the development of periodontitis.


Asunto(s)
Placa Dental/metabolismo , Proteína HMGN2/metabolismo , Periodontitis/metabolismo , Saliva/metabolismo , Estudios de Casos y Controles , Humanos , Porphyromonas gingivalis
8.
Caries Res ; 49(3): 291-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25924684

RESUMEN

Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.


Asunto(s)
Cariostáticos/análisis , Fluoruros/análisis , Antisépticos Bucales/uso terapéutico , Saliva/química , Dodecil Sulfato de Sodio/farmacología , Fluoruro de Sodio/uso terapéutico , Tensoactivos/farmacología , Adulto , Calcio/análisis , Calcio/farmacocinética , Cariostáticos/farmacocinética , Cariostáticos/uso terapéutico , Placa Dental/química , Placa Dental/metabolismo , Femenino , Fluoruros/farmacocinética , Humanos , Electrodos de Iones Selectos , Masculino , Persona de Mediana Edad , Saliva/metabolismo
9.
J Oral Maxillofac Surg ; 73(3): 451-64, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25544303

RESUMEN

PURPOSE: It is widely thought that inflammation and osteoclastogenesis result in hydroxyapatite (HA) resorption and sequestrum formation during osseous infections, and microbial biofilm pathogens induce the inflammatory destruction of HA. We hypothesized that biofilms associated with infectious bone disease can directly resorb HA in the absence of host inflammation or osteoclastogenesis. Therefore we developed an in vitro model to test this hypothesis. MATERIALS AND METHODS: Customized HA discs were manufactured as a substrate for growing clinically relevant biofilm pathogens. Single-species biofilms of Streptococcus mutans, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans and mixed-species biofilms of C albicans plus S mutans were incubated on HA discs for 72 hours to grow mature biofilms. Three different non-biofilm control groups also were established for testing. HA discs were then evaluated by means of scanning electron microscopy, micro-computed tomography metrotomography, x-ray spectroscopy, and confocal microscopy with planimetric analysis. In addition, quantitative cultures and pH assessment were performed. Analysis of variance was used to test for significance between treatment and control groups. RESULTS: All investigated biofilms were able to cause significant (P < .05) and morphologically characteristic alterations in HA structure as compared with controls. The highest number of alterations observed was caused by mixed biofilms of C albicans plus S mutans. S mutans biofilm incubated in medium with additional sucrose content was the most detrimental to HA surfaces among single-species biofilms. CONCLUSIONS: Our findings suggest that direct microbial resorption of bone is possible in addition to immune-mediated destruction, which has important translational implications for the pathogenesis of chronic bone infections and for targeted antimicrobial therapeutics.


Asunto(s)
Biopelículas , Durapatita/metabolismo , Carga Bacteriana , Técnicas Bacteriológicas , Biopelículas/crecimiento & desarrollo , Candida albicans/crecimiento & desarrollo , Candida albicans/metabolismo , Técnicas de Cocultivo , Recuento de Colonia Microbiana , Medios de Cultivo , Placa Dental/metabolismo , Placa Dental/microbiología , Durapatita/química , Humanos , Concentración de Iones de Hidrógeno , Imagenología Tridimensional , Microscopía Confocal , Microscopía Electrónica de Rastreo , Micología/métodos , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/metabolismo , Espectrometría por Rayos X , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/metabolismo , Streptococcus mutans/crecimiento & desarrollo , Streptococcus mutans/metabolismo , Sacarosa/metabolismo , Tomografía , Microtomografía por Rayos X
10.
J Mater Sci Mater Med ; 26(1): 5372, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25604698

RESUMEN

The aim of this study was to investigate the impact of resin matrix chemistry and filler fraction on biofilm formation on the surface of experimental resin-based composites (RBCs). Specimens were prepared from eight experimental RBC formulations differing in resin matrix blend (BisGMA/TEGDMA in a 7:3 wt% ratio or UDMA/aliphatic dimethacrylate in a 1:1 wt% ratio) and filler fraction (no fillers; 65 wt% dental glass with an average diameter of 7 or 0.7 µm or 65 wt% SiO2 with an average diameter of 20 nm). Surface roughness, surface free energy, and chemical surface composition were determined; surface topography was visualized using atomic force microscopy. Biofilm formation was simulated under continuous flow conditions for a 48 h period using a monospecies Streptococcus mutans and a multispecies biofilm model. In the monospecies biofilm model, the impact of the filler fraction overruled the influence of the resin matrix, indicating lowest biofilm formation on RBCs with nano-scaled filler particles and those manufactured from the neat resin blends. The multispecies model suggested a more pronounced effect of the resin matrix blend, as significantly higher biofilm formation was identified on RBCs with a UDMA/dimethacrylate matrix blend than on those including a BisGMA/TEGDMA matrix blend but analogous filler fractions. Although significant differences in surface properties between the various materials were identified, correlations between the surface properties and biofilm formation were poor, which highlights the relevance of surface topography and chemistry. These results may help to tailor novel RBC formulations which feature reduced biofilm formation on their surface.


Asunto(s)
Biopelículas , Resinas Compuestas/química , Streptococcus mutans/crecimiento & desarrollo , Materiales Dentales/química , Placa Dental/metabolismo , Vidrio/química , Humanos , Ensayo de Materiales , Metacrilatos/química , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Silanos/química , Propiedades de Superficie
11.
J Periodontal Res ; 49(1): 55-61, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23550893

RESUMEN

OBJECTIVE: To investigate the hypothesis that levels of interferon (IFN)-γ and interleukin (IL)-4, as well as the newer cytokines IL-33 and thymic stromal lymphopoietin (TSLP), in gingival crevicular fluid (GCF) samples differ from sites of patients at various clinical stages of periodontal disease and controls. BACKGROUND: Periodontal diseases result from the complex interplay between pathogenic bacteria and the host's immune responses. Several inflammatory mediators, such as IFN-γ and IL-4, have been detected in GCF samples in patients with periodontitis, but the results are mostly contradicting due to the lack of uniformity and collection of sites and methods of analysis. MATERIAL AND METHODS: GCF samples were collected from sites with different clinical characteristics (healthy, gingivitis and periodontitis sites) from periodontally healthy ( n = 14), plaque-induced gingivitis (n = 17) and chronic periodontitis (n = 11) subjects. The GCF samples were analyzed for the frequency of detection and levels of IFN-γ, IL-4, IL-33 and TSLP using a multiplex bead immunoassay. RESULTS: Inflamed sites in both patients with plaque-induced gingivitis and chronic periodontitis showed statistically significantly higher volume of GCF compared to non-inflamed sites in all patients. IFN-γ could be detected in about 50-70% of the samples analyzed and at significantly higher levels in sites with periodontitis compared to healthy sites in patients with chronic periodontitis (p = 0.035). We also show a statistically significant decrease of IFN-? in healthy sites of patients with chronic periodontitis as compared to gingivitis sites in patients with plaque-induced gingivitis (p = 0.047). Only some of the GCF samples showed detectable levels for IL-4 and TSLP, while IL-33 was below the detection level in all samples collected. CONCLUSIONS: These results suggest that IFN-γ levels in GCF depend on the clinical stage of the site and not on the disease stage of the patient, but need to be expanded to a greater number of subjects and additional analysis of corresponding gingival tissue biopsies for cytokine gene expression.


Asunto(s)
Citocinas/análisis , Líquido del Surco Gingival/química , Gingivitis/metabolismo , Interferón gamma/análisis , Interleucina-4/análisis , Interleucina-7/análisis , Interleucinas/análisis , Periodontitis/metabolismo , Adulto , Factores de Edad , Anciano , Pérdida de Hueso Alveolar/metabolismo , Periodontitis Crónica/metabolismo , Placa Dental/metabolismo , Femenino , Líquido del Surco Gingival/inmunología , Humanos , Interleucina-33 , Masculino , Persona de Mediana Edad , Pérdida de la Inserción Periodontal/metabolismo , Bolsa Periodontal/metabolismo , Periodoncio/metabolismo , Células del Estroma/patología , Timo/patología , Adulto Joven , Linfopoyetina del Estroma Tímico
12.
Caries Res ; 48(2): 174-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24401761

RESUMEN

The purpose of this study is to determine whether a calcium (Ca) prerinse used before a 228 µg/g (ppm) fluoride (F) rinse would induce the formation of 'calcium fluoride-like' (CaF2-like) deposits in human dental plaque. Sixty minutes after the use of the Ca prerinse/F rinse, plaque samples were collected from 10 volunteers, homogenized, and split into 2 aliquots. The plaque mass from one aliquot was then extracted with a 'plaque-like' solution that extracted all the CaF2-like deposits. The total F in both aliquots was then determined and compared. The results demonstrated that, as in previous studies, the Ca prerinse induced large increases in plaque fluid and total plaque F. However, unlike previous results without the Ca prerinse, 30% of the plaque F deposits were CaF2 or CaF2-like. Given that maintaining an elevated F concentration in the vicinity of a developing lesion may play an important role in the cariostatic effect of this ion, and the potential advantages of CaF2-like deposits as an F source, these results suggest that a Ca prerinse may increase the cariostatic effect of topical agents.


Asunto(s)
Fluoruro de Calcio/metabolismo , Calcio/uso terapéutico , Cariostáticos/uso terapéutico , Placa Dental/metabolismo , Antisépticos Bucales/uso terapéutico , Fluoruro de Sodio/uso terapéutico , Adulto , Calcio/administración & dosificación , Compuestos de Calcio/administración & dosificación , Compuestos de Calcio/uso terapéutico , Fluoruro de Calcio/análisis , Cariostáticos/administración & dosificación , Cariostáticos/análisis , Placa Dental/química , Femenino , Fluoruros/análisis , Humanos , Concentración de Iones de Hidrógeno , Lactatos/administración & dosificación , Lactatos/uso terapéutico , Masculino , Persona de Mediana Edad , Antisépticos Bucales/administración & dosificación , Fluoruro de Sodio/administración & dosificación , Fluoruro de Sodio/análisis , Adulto Joven
13.
Caries Res ; 48(1): 73-89, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24248036

RESUMEN

Using a one-dimensional mathematical model that couples tooth demineralisation and remineralisation with metabolic processes occurring in the dental plaque, two mechanisms for subsurface lesion formation were evaluated. It was found that a subsurface lesion can develop only as the result of alternating periods of demineralisation (acid attack during sugar consumption) and remineralisation (resting period) in tooth enamel with uniform mineral composition. It was also shown that a minimum plaque thickness that can induce an enamel lesion exists. The subsurface lesion formation can also be explained by assuming the existence of a fluoride-containing layer at the tooth surface that decreases enamel solubility. A nearly constant thickness of the surface layer was obtained with both proposed mechanisms. Sensitivity analysis showed that surface layer formation is strongly dependent on the length of remineralisation and demineralisation cycles. The restoration period is very important and the numerical simulations support the observation that often consumption of sugars is a key factor in caries formation. The calculated profiles of mineral content in enamel are similar to those observed experimentally. Most probably, both studied mechanisms interact in vivo in the process of caries development, but the simplest explanation for subsurface lesion formation remains the alternation between demineralisation and remineralisation cycles without any pre-imposed gradients.


Asunto(s)
Esmalte Dental/patología , Placa Dental/complicaciones , Modelos Biológicos , Desmineralización Dental/etiología , Equilibrio Ácido-Base/fisiología , Algoritmos , Cariostáticos/farmacología , Caries Dental/etiología , Caries Dental/metabolismo , Caries Dental/microbiología , Esmalte Dental/metabolismo , Solubilidad del Esmalte Dental/efectos de los fármacos , Placa Dental/metabolismo , Placa Dental/microbiología , Sacarosa en la Dieta/efectos adversos , Durapatita/metabolismo , Fermentación , Fluoruros/farmacología , Glucosa/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Hidroxiapatitas/metabolismo , Radical Hidroxilo/metabolismo , Ácido Láctico/metabolismo , Minerales/metabolismo , Oxidantes/metabolismo , Saliva/metabolismo , Streptococcus/metabolismo , Desmineralización Dental/metabolismo , Remineralización Dental
14.
Am J Dent ; 27(2): 100-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25000668

RESUMEN

PURPOSE: To evaluate the clinical effect on plaque metabolism of a dentifrice containing 1.5% arginine, an insoluble calcium compound and 1,450 ppm fluoride compared to a commercially available dentifrice containing 1,450 ppm fluoride in a silica base. METHODS: A 12-week, parallel, randomized, double-blind study using 48 subjects was conducted at the Colgate-Palmolive Technology Center (Piscataway, NJ, USA). One group used a test dentifrice containing 1.5% arginine, an insoluble calcium compound and 1,450 ppm fluoride as sodium monofluorophosphate (MFP), and the other group used a commercial silica dentifrice with 1,450 ppm fluoride as sodium fluoride (NaF) as a control. Plaque metabolism analyses were conducted at baseline and after 2, 4, 6, 8, and 12 weeks of assigned product use. The plaque analyses included pH measurements before and after a sucrose rinse, ammonia production and lactic acid production. RESULTS: Subjects using the test dentifrice had significantly higher plaque pH values before (P< or = 0.01) and after (P< or = 0.045) a sucrose challenge than those using the commercially available control dentifrice. Subjects using the test dentifrice also produced higher levels of ammonia and lower levels of lactic acid compared to subjects using the control dentifrice.


Asunto(s)
Arginina/uso terapéutico , Fosfatos de Calcio/uso terapéutico , Placa Dental/metabolismo , Dentífricos/uso terapéutico , Fluoruros/uso terapéutico , Fosfatos/uso terapéutico , Adulto , Amoníaco/análisis , Cariogénicos/farmacología , Cariostáticos/uso terapéutico , Placa Dental/química , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis , Masculino , Persona de Mediana Edad , Ácido Silícico/uso terapéutico , Fluoruro de Sodio/uso terapéutico , Sacarosa/farmacología , Pastas de Dientes/uso terapéutico , Adulto Joven
15.
BMC Gastroenterol ; 13: 7, 2013 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-23311469

RESUMEN

BACKGROUND: Numerous diagnostic tests are available to detect Helicobactor pylori (H. pylori). There has been no single test available to detect H. pylori infection reliably. We evaluated the accuracy of a new fluorescence quantitative PCR (fqPCR) for H. pylori detection in children. METHODS: Gastric biopsy specimens from 138 children with gastritis were sent for routine histology exam, rapid urease test (RUT) and fqPCR. 13C-urea breath test (13C-UBT) was carried out prior to endoscopic procedure. Gastric fluids and dental plaques were also collected for fqPCR analysis. RESULTS: 38 children (27.5%) were considered positive for H. pylori infection by gold standard (concordant positive results on 2 or more tests). The remaining 100 children (72.5%) were considered negative for H. pylori. Gastric mucosa fqPCR not only detected all 38 H. pylori positive patients but also detected 8 (8%) of the 100 gold standard-negative children or 11 (10.7%) of the 103 routine histology-negative samples. Therefore, gastric mucosa fqPCR identified 46 children (33.3%) with H. pylori infection, significantly higher than gold standard or routine histology (P<0.01). Both gastric fluid and dental plaque fqPCR only detected 32 (23.2%) and 30 (21.7%) children with H. pylori infection respectively and was significantly less sensitive than mucosa fqPCR (P<0.05) but was as sensitive as non-invasive UBT. CONCLUSIONS: Gastric mucosa fqPCR was more sensitive than routine histology, RUT, 13C-UBT alone or in combination to detect H. pylori infection in children with chronic gastritis. Either gastric fluid or dental plaque PCR is as reliable as 13C-UBT for H. pylori detection.


Asunto(s)
Fluorescencia , Gastritis/diagnóstico , Gastritis/microbiología , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Biopsia , Pruebas Respiratorias , Niño , Preescolar , Placa Dental/metabolismo , Femenino , Jugo Gástrico/metabolismo , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Gastritis/metabolismo , Infecciones por Helicobacter/metabolismo , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Estudios Prospectivos , Sensibilidad y Especificidad , Estómago/microbiología , Estómago/patología , Ureasa/metabolismo
16.
Odontology ; 101(1): 2-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23224410

RESUMEN

The Stephan Curve has played a dominant role in caries research over the past several decades. What is so remarkable about the Stephan Curve is the plethora of interactions it illustrates and yet acid production remains the dominant focus. Using sophisticated technology, it is possible to measure pH changes in plaque; however, these observations may carry a false sense of accuracy. Recent observations have shown that there may be multiple pH values within the plaque matrix, thus emphasizing the importance of the milieu within which acid is formed. Although acid production is indeed the immediate proximate cause of tooth dissolution, the influence of alkali production within plaque has received relative scant attention. Excessive reliance on Stephan Curve leads to describing foods as "safe" if they do not lower the pH below the so-called "critical pH" at which point it is postulated enamel dissolves. Acid production is just one of many biological processes that occur within plaque when exposed to sugar. Exploration of methods to enhance alkali production could produce rich research dividends.


Asunto(s)
Ácidos/metabolismo , Caries Dental/metabolismo , Esmalte Dental/efectos de los fármacos , Placa Dental/metabolismo , Ácidos/efectos adversos , Álcalis/metabolismo , Caries Dental/etiología , Humanos , Concentración de Iones de Hidrógeno , Desgaste de los Dientes/etiología
17.
J Clin Dent ; 24(3): 79-87, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24660269

RESUMEN

In spite of obvious achievements in prevention, caries remains a prevalent disease. Fluorides are effective by inhibiting enamel and dentin demineralization and enhancing remineralization, but have little or no influence on bacterial processes in dental plaque. Dental caries is a continuum of stages from reversible, early lesions to irreversible, pre-cavitated lesions and, ultimately, to cavities. Prevention should focus on strengthening protective and reducing pathological factors, and careful monitoring of the disease state. While fluoride and the mineral aspects of caries have been in focus for decades, new insights into the etiology of caries have generated novel concepts and approaches to its prevention and treatment. The observation that some plaque bacteria can produce alkali metabolites and, thus, raise pH or neutralize acid formed in plaque has long been known. Such pH rise factors are related to caries susceptibility. Nourishing the plaque with substrates that encourage alkali-producing reactions is a protective factor in the caries continuum. This article reviews the results of clinical studies with a novel toothpaste containing 1.5% arginine, an insoluble calcium compound, and fluoride which have demonstrated superior remineralization of white spot enamel lesions and rehardening of root surface lesions, favorable effects on the de-/remineralization balance, as well as superior cavity prevention efficacy compared to toothpaste with fluoride alone. Studies have also confirmed formation of ammonia and elevated pH levels in subjects using the arginine-containing toothpaste. This novel toothpaste effectively combines the established effects of fluoride on de- and remineralization with reduction of caries-inducing pathological factors resulting from plaque metabolism.


Asunto(s)
Arginina/uso terapéutico , Caries Dental/prevención & control , Pastas de Dientes/uso terapéutico , Adulto , Calcio/uso terapéutico , Niño , Índice CPO , Caries Dental/microbiología , Caries Dental/fisiopatología , Susceptibilidad a Caries Dentarias , Placa Dental/metabolismo , Fluorescencia , Humanos , Concentración de Iones de Hidrógeno , Lactobacillus , Streptococcus mutans , Remineralización Dental , Pastas de Dientes/química
18.
J Clin Dent ; 24 Spec no A: A45-54, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24156139

RESUMEN

OBJECTIVE: This paper presents the results of a clinical study assessing the in vivo effects on plaque metabolism of a new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride compared to a commercially available dentifrice containing 1450 ppm fluoride alone. METHODS: A four-week, parallel, randomized, double-blind clinical study using 54 subjects was conducted at the New York University College of Dentistry Bluestone Center for Clinical Research. Two study groups used the following products for two weeks: 1) a dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride as sodium monofluorophosphate (MFP; test); and 2) a commercial silica dentifrice with 1450 ppm fluoride as sodium fluoride (NaF; control). In the following two-week period, all subjects used the control product. The effects of product use on plaque metabolism in vivo were assessed by conducting ex vivo analyses at baseline, after two weeks of assigned product use, and after two weeks of control product use. These plaque analyses comprised pH measurements before and after an in vivo sucrose rinse, and measurements of ammonia production and lactate production. RESULTS: The study showed that subjects using the test dentifrice, containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, had significantly higher plaque pH values before the sucrose challenge than those using the commercially available control dentifrice (p < or = 0.01). Plaque samples from subjects using the arginine-containing dentifrice also produced significantly higher levels of ammonia (p < or = 0.01). Subjects using the arginine-containing dentifrice also had a directionally higher plaque pH after the sucrose challenge, and their plaque samples produced a directionally lower level of lactate during the two-week treatment period compared to subjects using the control dentifrice. Following two weeks of subsequent use of the control product, there were no significant differences in plaque metabolism measures between groups. CONCLUSION: A new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride has been shown in this study to modulate plaque metabolism, increasing ammonia production and decreasing lactate production, thereby increasing plaque pH to help restore a pH-neutral environment.


Asunto(s)
Arginina/uso terapéutico , Cariostáticos/uso terapéutico , Placa Dental/metabolismo , Dentífricos/uso terapéutico , Fluoruros/uso terapéutico , Fosfatos/uso terapéutico , Amoníaco/metabolismo , Calcio/uso terapéutico , Método Doble Ciego , Estudios de Seguimiento , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/metabolismo , Dióxido de Silicio/uso terapéutico , Fluoruro de Sodio/uso terapéutico , Sacarosa/metabolismo
19.
J Clin Dent ; 24 Spec no A: A32-44, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24156138

RESUMEN

OBJECTIVE: The primary objective of the three studies reported in this paper was to evaluate the effects of new dentifrices containing 1.5% arginine, an insoluble calcium compound, and fluoride for their ability to promote remineralization of demineralized enamel, and to prevent mineral loss from sound enamel specimens. A secondary objective was to determine the effects on plaque metabolism with respect to the conversion of arginine to ammonia and sucrose to lactic acid. METHODS: In Study 1, an intraoral remineralization/demineralization clinical model was used to assess the ability to promote remineralization of enamel of two dentifrices containing 1.5% arginine and 1450 ppm fluoride, as sodium monofluorophosphate (MFP), relative to a positive control with dicalcium phosphate dihydrate (Dical) and 1450 ppm fluoride, and a negative control with Dical and 250 ppm fluoride. One of the arginine-containing dentifrices contained Dical, and the other contained calcium carbonate as the source of insoluble calcium. Microradiography and image analysis were used to measure mineral changes. The study used a double-blind crossover design with a two-week treatment period. Each treatment period was preceded by a one-week washout period. Each product was used twice a day for two weeks. In the two other studies, the ability of dentifrices containing 1.5% arginine and fluoride to prevent demineralization of sound enamel blocks was assessed using an intraoral demineralization/remineralization clinical model and a double-blind crossover design with a five-day treatment period. A one-week minimum washout period preceded each treatment phase. Microhardness was used to assess mineral changes. Cariogenic challenges were administered by dipping each intraoral retainer into a 10% sucrose solution four times per day. Each product was used twice per day during the treatment period. Plaque was harvested from the specimens to measure the ability of the plaque to convert arginine to ammonia (Studies 2 and 3) and sucrose to lactic acid (Study 3) at the end of each treatment period. In Study 2, a dentifrice containing 1.5% arginine, Dical, and 1450 ppm fluoride as MFP was compared to a matched positive control containing 1450 ppm fluoride and to a matched negative control containing 250 ppm fluoride. In Study 3, a dentifrice containing 1.5% arginine, calcium carbonate, and 1000 ppm fluoride as MFP was compared to a matched positive control containing 1000 ppm fluoride and to a matched negative control containing 0 ppm fluoride. RESULTS: In Study 1, the percent mineral changes were +18.64, +16.77, +4.08, and -24.95 for the 1.5% arginine/Dical/1450 ppm fluoride, the 1.5% arginine/calcium carbonate/1450 ppm fluoride, the positive control, and negative control dentifrices, respectively. Study validation was successfully achieved by showing that the positive control was statistically significantly better that the negative control in promoting remineralization (p = 0.0001). The two arginine-containing test products were statistically significantly better than the positive control (p < 0.05). No significant difference was observed in efficacy between the two arginine-containing products, indicating that efficacy in promoting remineralization was independent of the choice of Dical or calcium carbonate as the source of insoluble calcium. In Study 2, the percent demineralization values were -8.50, +1.67, and +12.64 for the 1.5% arginine/Dical/1450 ppm fluoride, the positive control, and negative control dentifrices, respectively. Study validation was successfully achieved by showing that the positive control was statistically significantly better at preventing demineralization than the negative control (p < 0.0001). The arginine-containing dentifrice was shown to be statistically significantly better at preventing enamel demineralization than the positive control (p < 0.0001). Plaque metabolism measures for plaque exposed to the three treatments gave the following values for ammonia production after an arginine-sucrose challenge, expressed in nanomoles per milligram plaque: 162.7; 105.4; and 115.9 for the 1.5% arginine/Dical/1450 ppm fluoride, positive control, and negative control dentifrices, respectively. No statistically significant differences were observed between the three treatments, but the arginine-based dentifrice showed directionally higher ammonia production than both the positive and negative controls In Study 3, the percent demineralization values were +1.16, +4.96, and +15.34, for the 1.5% arginine/calcium carbonate/1 000 ppm fluoride, the positive control, and negative control dentifrices, respectively. Study validation was successfully achieved by showing that the positive control was statistically significantly better at preventing demineralization than the negative control (p < 0.0001). The arginine-containing dentifrice was shown to be statistically significantly better at preventing enamel demineralization than the positive control (p < 0.05). Plaque metabolism measures for plaque exposed to the three treatments gave the following values for ammonia production after an arginine-sucrose challenge, expressed in nanomoles per milligram plaque: 99.6; 56.2; and 42.2 for the 1.5% arginine/calcium carbonate/1000 ppm fluoride, the positive control, and negative control dentifrices, respectively. Plaque treated with the arginine- containing dentifrice produced significantly more ammonia than the positive and negative control dentifrices (p < 0.05). No significant difference in ammonia production was observed between the two controls. Lactic acid production after a sucrose challenge gave the following values, expressed as nanomoles per milligram plaque: 4.06; 5.12; and 4.64 for the 1.5% arginine/calcium carbonate/1000 ppm fluoride, the positive control, and negative control dentifrices, respectively. No significant difference was observed between the three treatments, but the arginine-based treatment showed directionally lower lactic acid production. RESULTS: The results of these three studies show that dentifrices containing 1.5% arginine, an insoluble calcium compound, and fluoride have a significantly improved ability to promote remineralization and prevent demineralization of enamel relative to dentifrices containing the same level of fluoride alone. Two different sources of insoluble calcium were evaluated, Dical and calcium carbonate. Dentifrices with Dical and with calcium carbonate, each in combination with 1.5% arginine and fluoride, provided superior efficacy as compared to matched dentifrices with fluoride alone, and the two products demonstrated comparable efficacy in promoting remineralization. The results of these studies demonstrate that the addition of 1.5% arginine to Dical-and calcium carbonate-based fluoride dentifrices provides superior efficacy in preventing demineralization and promoting remineralization, and, further, indicate that he arginine-containing dentifrices enhance the ability of plaque to metabolize arginine to ammonia.


Asunto(s)
Arginina/uso terapéutico , Cariostáticos/uso terapéutico , Esmalte Dental/efectos de los fármacos , Placa Dental/metabolismo , Dentífricos/uso terapéutico , Fluoruros/uso terapéutico , Fosfatos/uso terapéutico , Desmineralización Dental/prevención & control , Remineralización Dental/métodos , Adolescente , Adulto , Anciano , Compuestos de Amonio/metabolismo , Arginina/metabolismo , Calcio/uso terapéutico , Carbonato de Calcio/uso terapéutico , Fosfatos de Calcio/uso terapéutico , Estudios Cruzados , Método Doble Ciego , Femenino , Dureza , Humanos , Ácido Láctico/metabolismo , Masculino , Microrradiografía , Persona de Mediana Edad , Minerales/análisis , Sacarosa/metabolismo , Resultado del Tratamiento , Adulto Joven
20.
Expert Rev Proteomics ; 9(3): 311-23, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22809209

RESUMEN

This review covers developments in the study of polymicrobial communities, biofilms and selected areas of host response relevant to dental plaque and related areas of oral biology. The emphasis is on recent studies in which proteomic methods, particularly those using mass spectrometry as a readout, have played a major role in the investigation. The last 5-10 years have seen a transition of such methods from the periphery of oral biology to the mainstream, as in other areas of biomedical science. For reasons of focus and space, the authors do not discuss biomarker studies relevant to improved diagnostics for oral health, as this literature is rather substantial in its own right and deserves a separate treatment. Here, global gene regulation studies of plaque-component organisms, biofilm formation, multispecies interactions and host-microbe interactions are discussed. Several aspects of proteomics methodology that are relevant to the studies of multispecies systems are commented upon.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Placa Dental/microbiología , Bacterias Anaerobias Gramnegativas/aislamiento & purificación , Bacterias Anaerobias Gramnegativas/patogenicidad , Interacciones Huésped-Patógeno , Proteómica/métodos , Placa Dental/metabolismo , Fusobacterium nucleatum/aislamiento & purificación , Fusobacterium nucleatum/patogenicidad , Humanos , Interacciones Microbianas/fisiología , Enfermedades Periodontales/microbiología , Porphyromonas gingivalis/aislamiento & purificación , Porphyromonas gingivalis/patogenicidad , Prevotella intermedia/aislamiento & purificación , Prevotella intermedia/patogenicidad , Treponema denticola/aislamiento & purificación , Treponema denticola/patogenicidad , Virulencia
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