Angelika S. Callaway
Research interests
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InterestsMicrobial Ecology, Microbiology Techniques, Microbial Culture, PCR, Electrophoresis
Other
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Scientific MembershipsAmerican Society for Microbiology
VAAM
ORCA
International Association of Dental Research/Continental European Division
Publications
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0.64Impact points
Modeling of S mutans and A naeslundii acid production in vitro with caries incidence of low- and high-risk children.
Quintessence international (Berlin, Germany : 1985). 05/2012; 43(5):413-20.
Objectives: Nowadays, the extended ecological plaque hypothesis equates dental health with the occurrence of acidogenic generalists in the plaque flora and explains disease?the irreversible demineralization of the dental hard tissue?by an ecologic shift in plaque composition, favoring acidogenic and... [more] Objectives: Nowadays, the extended ecological plaque hypothesis equates dental health with the occurrence of acidogenic generalists in the plaque flora and explains disease?the irreversible demineralization of the dental hard tissue?by an ecologic shift in plaque composition, favoring acidogenic and aciduric specialists, following repeated conditions of high sugar. In the present study, aspects of the extended ecological plaque hypothesis were examined in retrospect. Method and Materials: Serving as a basis were data on (1) the caries incidence of children, classified according to their DMFT as having low or high caries risk; (2) the qualitative plaque composition of the children with the prevalence of mutans streptococci and actinomyces; (3) the amounts of acid and acid tolerance, determined by pH state titration (glucose), of representatively isolated strains of mutans streptococci and actinomyces; (4) the extrapolation of the acid amount to the occurrence of mutans streptococci and actinomyces in the plaque of children; and (5) the relationship between the extrapolated acid amount in plaque and caries incidence and the respective classification of the children into low and high caries risk. Results: The synoptic consideration of the numbers of A naeslundii and S mutans in plaque of children, with their capacity for acid production in vitro, reflected the caries risk classification. Conclusion: The analysis of the clinical, microbiologic, and in vitro findings concerning the virulence of the plaque isolates supports the extended ecological plaque hypothesis. Children with low caries risk had developed one new decayed surface within 4 years; children with high caries risk developed four within the same time period. (Quintessence Int 2012;43:413?420).
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Comparison between scaling-root-planing (SRP) and SRP/photodynamic therapy: six-month study.
Head & face medicine. 04/2012; 8(1):12.
ABSTRACT: INTRODUCTION: The purpose of this long-term clinical study was to examine the additional efficacy of photodynamic therapy (PDT) to scaling and root planing (SRP) in patients with chronic periodontal disease. METHODS: A total of 22 patients (mean age: 59.3 +/- 11.7 years) with chronic perio... [more] ABSTRACT: INTRODUCTION: The purpose of this long-term clinical study was to examine the additional efficacy of photodynamic therapy (PDT) to scaling and root planing (SRP) in patients with chronic periodontal disease. METHODS: A total of 22 patients (mean age: 59.3 +/- 11.7 years) with chronic periodontal disease and four teeth with probing depth [greater than or equal to] 5 mm were enrolled in the study. Inclusion criteria were: no systemic disease, no smoking, no pregnancy and no long-term medication. Beside the anamnesis, the following clinical parameters were assessed at baseline (one week before therapy), and one, three and six months after the therapy: bleeding on probing (BOP), plaque index (PI) probing depth (PD), and clinical attachment loss. All measurements were done by the same examiner with a fixed periodontal probe (PCP 12, Hu-Friedy) at six measurements/tooth. In each patient, two teeth were treated with SRP alone and two teeth with SRP and PDT (Periowave, Ondine Biopharma,Vancouver, Canada). The nonparametric Wilcoxon test for paired samples was used for comparison of the effect of the two treatments (p [less than or equal to] 0.05). RESULTS: After both types of treatment, the number of teeth positive for BOP declined. At baseline, the CAL measured 7.2 +/- 1.2 mm (SRP) or 8.1 +/- 1.3 mm (SRP/PDT); one, three and six months after both types of treatment an improvement was observed. At baseline, the probing depth was 5.9 +/- 0.8 mm (SRP) or 6.4 +/- 0.8 mm (SRP/PDT); after six months, an improvement of 2.4 +/- 0.6 mm (SRP) or 2.9 +/- 0.8 mm (SRP/PDT) was found. The greater reduction of the PD, achieved by a combination of SRP/PDT, was statistically significant after six months (p = 0.007). CONCLUSION: This clinical study demonstrates that SRP in combination with PDT seems to be effective and is therefore suitable as an adjuvant therapy to the mechanical conditioning of the periodontal pockets in patients with chronic periodontal diseases.
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1.13Impact points
The influence of micronutrients on oral and general health.
European journal of medical research. 11/2011; 16(11):514-8.
The aim of the present clinical pilot study was to examine the influence of a combination of micronutrients on individuals with high stress experience. 40 healthy students (28 female, 12 male) with a mean age of 27.1 ± 3.0 years, experiencing high examination stress, were chosen. After approval of t... [more] The aim of the present clinical pilot study was to examine the influence of a combination of micronutrients on individuals with high stress experience. 40 healthy students (28 female, 12 male) with a mean age of 27.1 ± 3.0 years, experiencing high examination stress, were chosen. After approval of the ethics commission, one group of students (n = 19) took a combination of micronutrients (Orthomol vital m/f) for three months, whereas other students (n = 21) served as control group. All participants underwent at the beginning and at the end of the trial a dental examination, a determination of 10 periodontal pathogens, a salivary and a blood analysis. In addition, the participants filled in a questionnaire on nutrition, quality of life and degree of stress experienced during their final examinations. The evaluation of the results, obtained at the end of the trial period, showed that for all students a slight worsening of oral hygiene and an increased consumption of unhealthy food could be observed. The intake of the micronutrients led to a slight improvement of the degree of gingival inflammation in comparison to the control group. The blood analysis showed an increase in vitamin (vitamin C, vitamin E) and zinc concentrations, and a lower increase in CRP. In the male subjects, a decrease in the serum concentrations of triglycerides (p = 0.073) and LDL (p = 0.048) was observed. This pilot study shows that micronutrients, taken during periods of high stress experience, had a beneficial effect on inflammatory processes and helped reduce the level of some of the plasma lipids in males, and thus can be recommended for supplementing the diet. However, additional studies with a higher number of subjects, also suffering from periodontal disease, are necessary to show the effect of a micronutrient supplementation more clearly.
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In vitro analysis of the cytotoxicity and the antimicrobial effect of four endodontic sealers.
Head & face medicine. 08/2011; 7:15.
The aim of this study was to investigate in vitro the cytotoxicity and antibacterial properties of four different endodontic sealers using human periodontal ligament fibroblast cell proliferation and visual analysis of growth inhibition. A silicone (GuttaFlow), silicate (EndoSequence BC), zinc oxide... [more] The aim of this study was to investigate in vitro the cytotoxicity and antibacterial properties of four different endodontic sealers using human periodontal ligament fibroblast cell proliferation and visual analysis of growth inhibition. A silicone (GuttaFlow), silicate (EndoSequence BC), zinc oxide eugenol (Pulp Canal Sealer EWT) and epoxy resin (AH Plus Jet) based sealer were incubated with PDL fibroblasts (10⁴ cells/ml, n=6) up to 96 h. Cell proliferation (RFU) was determined by means of the Alamar Blue assay. Cell growth and morphology was visualized by means of fluorescent dyes. Possible antibacterial properties of the different sealers were visualized by means of SEM (Enterococcus faecalis; Parvimonas micra). Fibroblast proliferation depended on sealer and cultivation time. After 72 and 96 h GuttaFlow and EndoSequence BC showed relatively non-cytotoxic reactions, while Pulp Canal Sealer EWT and AH Plus Jet caused a significant decrease of cell proliferation (p<0.001). Visualization of cell growth and morphology with various fluorescent dyes supplemented the results. No antibacterial effect of EndoSequence BC to P. micra was found, whereas GuttaFlow showed a weak, Pulp Canal Sealer EWT and AH Plus Jet extensive growth inhibition. Also, no antibacterial effect of GuttaFlow, EndoSequence BC or AH Plus Jet to E. faecalis could be detected. These in vitro findings reveal that GuttaFlow and EndoSequence BC can be considered as biocompatible sealing materials. However, prior to their clinical employment, studies regarding their sealing properties also need to be considered.
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1.65Impact points
Influence of different biomaterials on the viability of Aggregatibacter actinomycetemcomitans.
Archives of oral biology. 03/2011; 56(9):917-23.
The aim of the present in vitro study was to evaluate the effects of different biomaterials used for regenerative periodontal surgery on the growth of the periodontopathogen Aggregatibacter actinomycetemcomitans. Three commercially available biomaterials of synthetic origin (hydroxyapatite/beta-tric... [more] The aim of the present in vitro study was to evaluate the effects of different biomaterials used for regenerative periodontal surgery on the growth of the periodontopathogen Aggregatibacter actinomycetemcomitans. Three commercially available biomaterials of synthetic origin (hydroxyapatite/beta-tricalcium phosphate, nanostructured hydroxyapatite paste, oily calcium hydroxide suspension), a bovine-derived xenograft as well as an enamel matrix derivative (EMD) were added in different concentrations to calibrated suspensions of A. actinomycetemcomitans ATCC 43718/33384 (serotype b/c). Equal aliquots (0.1 ml) for the viability assay were taken after 5 min, 1h, 3h, 8h and 24h, plated on blood agar and incubated in an anaerobic environment for 48 h at 37°C. Viable cell counts were expressed as colony forming units (cfu)/0.1 ml. The results demonstrated that none of the investigated biomaterials could inhibit the growth of A. actinomycetemcomitans serotype b. A marked growth reduction of A. actinomycetemcomitans serotype c was observed in the presence of oily calcium hydroxide suspension and nanostructured hydroxyapatite. In contrast, no significant growth inhibition could be observed in the presence of hydroxyapatite/beta-tricalcium phosphate, enamel matrix derivative and bovine-derived xenograft. The results of the present study suggest that none of the investigated biomaterials possesses antimicrobial properties against A. actinomycetemcomitans serotype b. Therefore, the use of these biomaterials for regenerative procedures should be weighted critically in the presence of A. actinomycetemcomitans serotype b.
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0.80Impact points
Influence of bleaching agents on surface roughness of sound or eroded dental enamel specimens.
Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]. 12/2010; 22(6):391-9.
The aim of the present in vitro study was to assess the effect of bleaching agents on eroded and sound enamel specimens. Enamel specimens prepared from human permanent anterior teeth were incubated with different bleaching agents containing active ingredients as 7.5 or 13.5% hydrogen peroxide or 35%... [more] The aim of the present in vitro study was to assess the effect of bleaching agents on eroded and sound enamel specimens. Enamel specimens prepared from human permanent anterior teeth were incubated with different bleaching agents containing active ingredients as 7.5 or 13.5% hydrogen peroxide or 35% carbamide peroxide, ranging in pH from 4.9 to 10.8. The effect of the tooth whitening agents on surface roughness was tested for sound enamel surfaces as well as for eroded enamel specimens. To provoke erosive damage, the enamel specimens were incubated for 10 hours with apple juice (pH = 3.4). Afterwards, pretreated and untreated dental slices were incubated with one of the bleaching agents for 10 hours. The surface roughness (R(a)) of all enamel specimens (N = 80) was measured using an optical profilometric device. A descriptive statistical analysis of the R(a) values was performed. The study demonstrated that exposure to an acidic bleaching agent (pH = 4.9) resulted in a higher surface roughness (p = 0.043) than treatment with a high peroxide concentration (pH = 6.15). If the enamel surface was previously exposed to erosive beverages, subsequent bleaching may enhance damage to the dental hard tissue. Bleaching agents with a high concentration of peroxide or an acidic pH can influence the surface roughness of sound or eroded enamel.
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Diversity of Lactobacillus species in deep carious lesions of primary molars.
European archives of paediatric dentistry : official journal of the European Academy of Paediatric Dentistry. 08/2010; 11(4):181-6.
This was to determine the prevalence of Lactobacilli (LB) species in different stages of caries progression and are considered as secondary invaders of existing carious lesions and specialists for caries progression. Carious dentine samples were collected from 70 primary molars (M) during step-wise ... [more] This was to determine the prevalence of Lactobacilli (LB) species in different stages of caries progression and are considered as secondary invaders of existing carious lesions and specialists for caries progression. Carious dentine samples were collected from 70 primary molars (M) during step-wise (S1, S2: n = 35 M) or one-step (O1: n = 35 M) caries treatment and after 11 months of temporary restorations (S3, O2). LB were identified by selected physiological and biochemical characteristics, ratio of lactic acid isomers, electrophoretic mobilities of lactic acid dehydrogenases, and shotgun mass mapping by MALDI mass spectrometry. LB were isolated from 46% of soft dentine samples (S1). The prevalence of LB from hard dentine collected during caries excavation (O1) reached 34%, after 8 weeks of temporary filling (S2) 11%, and 9% each after 11 months of temporary restoration (S3, O2). The mean total bacterial counts (cfu) of soft dentine (S1) were 3.6 x 10⁵. From hard dentine during caries excavation (O1) 4.4x10⁴ cfu were calculated, at S2 3.7 x 10³ cfu, at S3 0.1 x 10³ cfu, and at O2 1.8 x 10³ cfu. The percentages of LB in the cfu for LB positive dentine samples were for S1 / S2 / S3 / O1 / O2: 60% (16 M)/34% (4 M)/54% (3 M)/57% (9 M), and 64% (3 M). Five LB species were identified from carious dentine: L. paracasei subsp. paracasei, L. paracasei subsp. tolerans, L. rhamnosus, L. gasseri, and L. alimentarius. Conclusions: While L. rhamnosus and L. paracasei subsp. paracasei occurred in all caries progression stages, the other species were found only sporadically. L. paracasei subsp. paracasei and L. rhamnosus might be the specialists of the LB in carious progression.
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Accuracy of a chair-side test for predicting caries risk compared with established methods. A pilot study.
Schweizer Monatsschrift für Zahnmedizin = Revue mensuelle suisse d'odonto-stomatologie = Rivista mensile svizzera di odontologia e stomatologia / SSO. 01/2010; 120(5):409-14.
The aim of this study was to determine the prognostic accuracy of a new chair-side test, determination of lactic-acid production on the tongue, for caries-risk assessment according to caries increment within two years. 35 children (6-8 years old) participated in the study. The past caries experience... [more] The aim of this study was to determine the prognostic accuracy of a new chair-side test, determination of lactic-acid production on the tongue, for caries-risk assessment according to caries increment within two years. 35 children (6-8 years old) participated in the study. The past caries experience (df-t1, DF-T1), caries at second deciduous molars (df-2.mol), approximal plaque index (API) were the clinical, and salivary counts of mutans streptococci (MS)/lactobacilli (LB) and lactic-acid production on the tongue (LAP) the subclinical predictors recorded at baseline. Two years later, the dental examination was repeated (df-t2/DF-T2). According to the increase in DF-T (delta DF-T), caries-risk groups (delta DF-T = 0 versus delta DF-T > or = 0) were built. To assess the prognostic accuracy sensitivity and specificity were calculated. Statistical analysis was performed using Spearman's test for nonparametric correlations. The DF-T increased from 0.3 +/- 0.8 to 1.2 +/- 1.6. 20 children were in the no-caries-risk and 15 in the caries-risk group. The p-value for the correlation of delta DF-T to API was 0.007 and to LB counts 0.069. The highest sensitivity and specificity levels were found for LB (65%/70%), LAP reached a maximum sensitivity of 33% with a specificity of 55%. According to the results, because of its insufficient prognostic accuracy the LAP test is not suitable as a sole screening-tool for an accurate caries-risk assessment.
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1.20Impact points
Prolonged in vitro exposure to white wines enhances the erosive damage on human permanent teeth compared with red wines.
Nutrition research (New York, N.Y.). 08/2009; 29(8):558-67.
The aim of this in vitro study was to determine and compare the erosive potentials of red and white wines, exerted on enamel surfaces prepared from extracted human permanent teeth. European wines (50 red, 50 white wines) from different regions were purchased, and the pH values were measured. Eight w... [more] The aim of this in vitro study was to determine and compare the erosive potentials of red and white wines, exerted on enamel surfaces prepared from extracted human permanent teeth. European wines (50 red, 50 white wines) from different regions were purchased, and the pH values were measured. Eight wines with different pH values were selected. Enamel samples with an average surface area of 25 mm(2) were prepared from 25 extracted permanent teeth from male and female patients aged 40 to 65 years and incubated with wines for up to 24 hours; the amounts of released calcium were determined colorimetrically, and mean surface roughness was measured with a profilometer. A quantitative elemental analysis for Ca was carried out in various depths (5-50 microm), using an electron probe microanalyzer. Incubation of the enamel surfaces with different wines caused a time-dependent release of calcium. After 24 hours, white wines caused a significantly higher (P = .003) Ca release (range: 8.74-28.56 mg dL(-1) 25 mm(-2)) than red wines (range: 4.85-19.43 mg dL(-1) 25 mm(-2)), whereas the values for surface roughness were similar (white wines: 2.67 +/- 0.92 microm; red wines: 2.64 +/- 0.66 mum). Incubation with white wines resulted in a higher loss of Ca down to a depth of 60 microm. In this study, it was demonstrated that white wines have higher erosive potentials than red wines. Within the limits of this in vitro study, it can be predicted that a frequent consumption of white wines might lead to severe dental erosion.
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1.13Impact points
Influence of apple juice on human enamel surfaces of the first and second dentition - an in vitro study.
European journal of medical research. 08/2008; 13(7):349-54.
Dental erosion caused by acidic beverages is common and occurs with increasing tendency. The aim of this in vitro study was to analyse the erosive potential of apple juice on human enamel samples from the first and second dentition. Apple-juice-containing beverages (n = 23) were selected, and pH and... [more] Dental erosion caused by acidic beverages is common and occurs with increasing tendency. The aim of this in vitro study was to analyse the erosive potential of apple juice on human enamel samples from the first and second dentition. Apple-juice-containing beverages (n = 23) were selected, and pH and buffering capacity were determined. Enamel samples were prepared from impacted, surgically removed wisdom teeth (20 mm superset2) and from deciduous teeth (16 mm superset2). Prepared enamel slices were incubated with a selected apple juice (pH = 3.5) for up to 24 h; the amounts of released calcium were determined colorimetrically, and mean surface roughness (Ra) of the enamel was measured using an optical profilometric device (perthometer, Mahr, Göttingen, Germany). Controls were incubated with a 0.9 % sodium chloride solution under the same conditions (37 degrees C, humidified atmosphere of 5% CO subset2 and 95 % air). The surfaces of the enamel samples were visually examined by CLSM (Leica TCS SP2). The pH-values of the apple juices ranged from 3.3 to 4.2. Incubating the enamel slices (from both dentitions) with a selected apple juice caused a time dependent release of calcium. After 24 h, the primary dentition showed Ca-release values of 0.61 +/- 0.035 mg/ 20 mm superset2 and the second dentition of 0.41 +/- 0.085 mg/ 20 mm superset2; the surface roughness for the primary teeth was 6.8 +/- 1.09 microm and for the second dentition 6.2 +/- 0.41 microm. CLSM show structural changes on all surfaces when compared to the controls. In this in vitro study, the erosive potential of apple juice on teeth of the first and second dentition could be demonstrated. However, it must be considered that numerous modifying factors influence the human enamel surface in vivo; therefore, a direct translation from in-vitro conditions can only be done with caution.
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Comparison of a new chairside test for caries risk assessment with established methods in children.
Schweizer Monatsschrift für Zahnmedizin = Revue mensuelle suisse d'odonto-stomatologie = Rivista mensile svizzera di odontologia e stomatologia / SSO. 02/2008; 118(8):702-8.
PURPOSE: The aim of this study was to compare the results of a new method, measurement of lactic-acid production on the tongue (LAP), with established methods of caries risk assessment in children. METHODS: One hundred nineteen children (6-10 years old) participated in the study. Data collection inc... [more] PURPOSE: The aim of this study was to compare the results of a new method, measurement of lactic-acid production on the tongue (LAP), with established methods of caries risk assessment in children. METHODS: One hundred nineteen children (6-10 years old) participated in the study. Data collection included number of carious lesions (D-T) and filled teeth (F-T), approximal plaque index (API), LAP, buffering capacity (BC), counts of mutans streptococci (MS) and lactobacilli (LB) in stimulated saliva. According to caries presence, the children were divided into low risk (LR group; D-T = 0) and high risk (HR group; D-T > or = 1) groups. Statistical analysis was performed using Chi-square test, Spearman's test for nonparametric correlations, uni- and multivariate regression analysis. RESULTS: Seventy-two children (F-T = 0.4 +/- 1.4) were in the LR and 47 (D-T = 2.5 +/- 2.7; F-T = 1.5 +/- 1.9) in the HR group. The correlation analysis verified statistically significant correlations between D-T and the salivary counts of MS/LB and between D-T and F-T. API correlated with F-T and LB, while F-T and LB also correlated with each other significantly. The counts of MS and LB showed also a significant correlation. The LAP showed a significant correlation only to F-T. Significances in univariate regression analysis were found for F-T, counts of LB and MS in saliva, and for LAP. The multivariate regression analysis indicated significances only for F-T and LB in saliva, but not for LAP. CONCLUSION: LAP might be useful only as a supplementary screening tool for caries risk assessment, but not as a sole predictor.
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Course of changes in salivary pH-values after intake of different beverages in young children.
Oral health & preventive dentistry. 01/2008; 6(2):159-64.
The aim of the study was to determine possible differences in decrease of pH-values of whole saliva, following the intake of different beverages. Twelve boys and 13 girls (4.9 +/- 0.9 years old) participated in this study. A dental examination was performed (dmft). Orange juice (pH = 3.67), instant ... [more] The aim of the study was to determine possible differences in decrease of pH-values of whole saliva, following the intake of different beverages. Twelve boys and 13 girls (4.9 +/- 0.9 years old) participated in this study. A dental examination was performed (dmft). Orange juice (pH = 3.67), instant fennel tea (pH = 7.38), whole milk (pH = 6.84) and mineral water (pH = 5.88) were tested. All beverages were given at the same time of day. Salivary pH and buffering capacities of the beverages were determined with a portable pH-meter. Immediately after intake of a beverage, and 5, 10, 15 and 25 minutes later, whole saliva was collected, and the pH-value was measured again. The statistical evaluation was performed using the Wilcoxon test for paired samples. Fifteen children had healthy dentitions. Ten subjects had a mean dmft of 1.1 +/- 2.3. The mean base salivary pH was 7.09 +/- 0.07, without differences between the children with and without dental decay. Mineral water led over the whole period of measurements to a significant rise in salivary pH (P < 0.05). Orange juice caused a significant reduction in the salivary pH during the first 10 minutes. After intake of instant tea or milk, significant reductions were found in the period of 5 to 10 minutes. After the intake of instant tea, the reduction was still significant after 15 minutes. During the period of 5 to 10 minutes, the change in pH (deltapH) in whole saliva differed significantly only between consumption of mineral water and other beverages (P < 0.01). With regard to dental health, a regular consumption of orange juice or sweetened instant teas should be discouraged.
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1.13Impact points
Antibiotic resistance testing of the total implant-associated micro-flora and its pure isolates.
European journal of medical research. 04/2007; 12(3):120-8.
OBJECTIVE: The aim of the present study was to examine antibiotic resistant strains among the implant-associated microorganisms in vitro, first as mixed cultures and again as pure isolates for resistance to one of five antibiotics. METHODS: Samples were taken with sterile paper points from the deepe... [more] OBJECTIVE: The aim of the present study was to examine antibiotic resistant strains among the implant-associated microorganisms in vitro, first as mixed cultures and again as pure isolates for resistance to one of five antibiotics. METHODS: Samples were taken with sterile paper points from the deepest pocket of one implant per patient (n = 24) to culture the total oral micro-flora. The samples were streaked on agar (Schaedler or BHI) and incubated for 7 d in an anaerobic atmosphere. All colonies were rinsed off the plates, aliquots were added to top-agar. Susceptibility against antibiotics (ampicillin, ampicillin + sulbactam, azithromycin and penicillin, moxifloxacin) was determined using the Etest. Resistant strains were picked, purified and characterized, and the Etests were repeated with a selection of the pure isolates. RESULT: The majority of the mixed cultures (67 - 100 %) showed complete antibiotic resistance. No association with clinical parameters like pocket depth, bleeding on probing or insertion of implants into transplanted bone could be found. Smoking and the surface of the implant also had no influence. 23 % of the 597 resistant colonies contained only yeasts, mostly isolated from irradiated tumour patients. Of the 458 resistant bacteria, the majority were Gram-positive cocci or rods. Staphylococci and M. micros were detected occasionally. The resistance for the 138 selected pure isolates was in most cases lower than for the total micro-flora, irrespective of the antibiotic. CONCLUSIONS: The higher resistance of the total flora might be explained by synergistic interactions between its members.
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1.13Impact points
Polymerase chain reaction-based simultaneous detection of selected bacterial species associated with closed periapical lesions.
European journal of medical research. 09/2005; 10(8):333-8.
PURPOSE: The aim of this study was to identify microorganisms which might be present in closed periapical lesions and to determine their relationship to conventional clinical parameters. - METHODS: In 11 patients, samples were taken with paper points from 14 teeth with periapical radiolucency, in se... [more] PURPOSE: The aim of this study was to identify microorganisms which might be present in closed periapical lesions and to determine their relationship to conventional clinical parameters. - METHODS: In 11 patients, samples were taken with paper points from 14 teeth with periapical radiolucency, in seven cases two samples were taken from two different sites of the same tooth (n=21). Clinical parameters were determined. The 16S rDNA of eleven bacterial species could be simultaneously detected via a modified polymerase chain reaction (PCR) based technique. - RESULTS: All samples contained more than one bacterial species. Most frequently, M. micros was detected alone or in combination with E. faecalis, P. aeruginosa, E. coli, F. nucleatum or S. sanguinis. When apical palpation was positive, often M. micros and F. nucleatum were both present. Other clinical symptoms like tenderness to percussion were not associated with a particular microflora. - CONCLUSIONS: In closed periapical lesions detected by radiography, specific bacteria were identified by means of a modified PCR technique. No clear associations between clinical symptoms and these bacteria were found. Surgical intervention might be indicated for some of the persistent lesions.
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1.14Impact points
Comparison of the efficacy of chemomechanical caries removal (Carisolv) with that of conventional excavation in reducing the cariogenic flora.
International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children. 06/2004; 14(3):182-91.
OBJECTIVES: The usage of minimally invasive procedures and attention to patient comfort are of great importance, especially for dental treatment in small children. This has led to the development of chemomechanical methods for caries removal. The aim of this study was to compare the efficacy of chem... [more] OBJECTIVES: The usage of minimally invasive procedures and attention to patient comfort are of great importance, especially for dental treatment in small children. This has led to the development of chemomechanical methods for caries removal. The aim of this study was to compare the efficacy of chemomechanical caries removal with that of conventional excavation in reducing the count of the cariogenic flora. DESIGN AND SETTING: Subjects for this study were chosen from children admitted to dental clinic for restorative procedures under general anaesthesia. SAMPLES AND METHODS: Twenty-one children (mean age 43.5 +/- 12.0 months) with early childhood caries were included in this study. Two primary teeth with comparable degrees of carious destruction were chosen in each child (n = 42) for caries removal with Carisolv' or by means of rotary instruments. Samples from carious dentine were taken with a sterile scraping instrument, then all softened dentine was removed and a second sample was taken. All samples (n = 84) were serially diluted and plated on two different nutrient agar plates. RESULTS: After 24 h of incubation, colony forming units were determined for total bacterial counts and lactobacilli. Twelve per cent of the samples from carious dentine contained more than 10(6) bacteria, 23.8% contained more than 10(5) lactobacilli. Both methods of caries removal produced a statistically significant reduction in the bacterial counts (P = 0.0001). In at least 90.5% of the samples taken after the removal, the total bacterial count was below 10(2), and in 95.2% lactobacilli fell below 10(2). CONCLUSION: These results indicate that the efficacy of chemomechanical removal of carious dentine in children by means of Carisolv' is comparable to the results obtained by conventional methods, and thus might serve as a suitable alternative.
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1.13Impact points
Effects of selected immunouppressive drugs on prostaglandin release, protein synthesis and cell proliferation in human gingival fibroblasts and on the growth of plaque bacteria.
European journal of medical research. 02/2003; 8(1):25-32.
BACKGROUND: Immunosuppressants play an essential role in transplantation therapy. In view of the side effects, e.g. gingival overgrowth, the present in vitro study was performed in order to investigate the effect of selected immunosuppressants on metabolic activities of gingival fibroblasts. Further... [more] BACKGROUND: Immunosuppressants play an essential role in transplantation therapy. In view of the side effects, e.g. gingival overgrowth, the present in vitro study was performed in order to investigate the effect of selected immunosuppressants on metabolic activities of gingival fibroblasts. Furthermore, the effect on the growth of six oral microorganisms was investigated. METHODS: Human gingival fibroblasts were incubated in the presence of azathioprine (Aza), cyclosporin A (CsA), tacrolimus (Tac) or mycophenolatmofetil (Myc). PGE subset 2 release was determined by means of a specific competitive enzyme immunoassay, using monoclonal antibodies specific for PGE subset 2 (clone E2R1). The protein content was measured spectrophotometrically. A redox indicator system was employed to assess the proliferation activity. In an additional trial the growth of six strains of oral bacteria (A. viscosus T14V, S. oralis H1, S. mutans 10449, C. gingivalis DR2001, A. actinomycetemcomitans Y4, and M. micros 33270) in the presence of the immunosuppressants was measured. RESULTS: In comparison with the controls, the PGE subset 2 release was increased by 39.3% following incubation with Aza, and by 77.0% with CsA. The protein concentrations (1 g immunosuppressant / ml medium) were reduced by 26.0% for Aza and 17.0% for Myc. Furthermore, a drug-dependent inhibition in the cell proliferation rate was noted after an incubation period of 6 hours (Aza 70.7%, CsA 78.2%, Myc 69.8%, Tac 64.0%). The most pronounced growth-inhibiting effects were observed for CsA at values ranging from 21.0% (S. mutans 10449) to 48.6% (A. viscosus T14V) growth inhibition. CONCLUSIONS: The present study with common immunsuppresants demonstrated both a medication- and dose-dependent alteration in the metabolic activity of gingival fibroblasts. Furthermore, growth-inhibitory effects on the selected bacterial strains could be observed.
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Reduction of the pH-values of whole saliva after the intake of apple juice containing beverages in children and adults.
Oral health & preventive dentistry. 01/2003; 1(3):229-36.
PURPOSE: The aim of the present study was to compare changes in salivary pH after intake of apple juice and its various dilutions with mineral water, in children and adults. MATERIALS AND METHODS: 15 children (mean age 4.4+/-0.9 years), and 15 adults (mean age 30+/-2.4 years) participated in this st... [more] PURPOSE: The aim of the present study was to compare changes in salivary pH after intake of apple juice and its various dilutions with mineral water, in children and adults. MATERIALS AND METHODS: 15 children (mean age 4.4+/-0.9 years), and 15 adults (mean age 30+/-2.4 years) participated in this study. Carbonated mineral water, apple juice and its various dilutions with carbonated mineral water were tested. The pH-value of unstimulated whole saliva was measured at the same time of day. The pH-value was measured again immediately after intake of a beverage, and 5, 10, 15 and 25 min later. The flow rate and buffering capacity of stimulated saliva, and the buffering capacity, calcium and phosphorus contents of the beverages were measured. The statistical evaluation of the data was performed employing the Wilcoxon test for paired samples. RESULTS: The mean base value of the pH of whole saliva was 7.0+/-0.2 (children), and 6.8+/-0.3 (adults). The differences in the flow rates of stimulated saliva in children and adults were statistically significant (p = 0.0003). The intake of mineral water led to a statistically significant rise in the salivary pH-value (p < 0.05). Undiluted and diluted apple juice caused a reduction in the salivary pH-values. Within the first 10 min the changes of pH in saliva only differed significantly between mineral water and the other beverages (p < 0.01). In the pH range of 5.8 - 7.0, mineral water had a weak buffering capacity, while undiluted apple juice had a high buffering capacity. CONCLUSIONS: With regard to dental and general health, only mineral water can be recommended for children.
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1.13Impact points
Effect of three mouthrinses, containing amine/stannous fluoride, herbal extracts or Emser salt on the growth of oral bacteria--an in vitro study.
European journal of medical research. 01/2001; 5(12):523-9.
BACKGROUND/AIMS: Clinical studies have shown the efficacy of mouthrinses in reducing plaque accumulation and inflammation of oral tissues. The aim of this in vitro study was to compare the effect of three mouthrinses: Meridol, an organic amine/ stannous fluoride solution; Parodontax, containing herb... [more] BACKGROUND/AIMS: Clinical studies have shown the efficacy of mouthrinses in reducing plaque accumulation and inflammation of oral tissues. The aim of this in vitro study was to compare the effect of three mouthrinses: Meridol, an organic amine/ stannous fluoride solution; Parodontax, containing herbal ingredients; and an 0.8 % Emser salt solution, on the growth of oral bacteria and dental plaque. METHODS: Growth of Actinomyces viscosus T14V, Capnocytophaga ochracea 25, C. sputigena 4, Actinobacillus actinomycetemcomitans (A.a.) Y4, and pooled supragingival plaque in the presence of the various mouthrinses, applied to paper discs, was tested in an agar diffusion test. In a second series of tests, the 4 bacterial strains were exposed to the agents for about 3 min to simulate rinsing, then the agent was removed, and the bacteria were inoculated into fresh nutrient broth. After 48 h bacterial growth was measured in a spectrophotometer and compared with the controls. RESULTS: In the agar diffusion test only Meridol, the organic amine/stannous fluoride-containing solution, could inhibit bacterial growth, except for A. a. Y4. When the bacteria where in contact with the agents for only a few minutes these results were confirmed. Neither Paradontax nor Emser salt inhibited the growth of the bacteria, and A. a. Y4 proved to be resistant to all three agents. Growth of the other three strains was inhibited by Meridol 92-99% (undiluted), 85-96% (1:5) and 83-98% (1:10). CONCLUSIONS: We conclude that only Meridol contains ingredients capable of inhibiting the growth of oral bacteria in vitro. The efficacy of the other two mouthrinses in reducing plaque accumulation in vivo has to be explained by other mechanisms.
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2.11Impact points
International Committee on Systematic Bacteriology Subcommittee on the taxonomy of Bifidobacterium, Lactobacillus and related organisms. Minutes of the meetings, 4 and 6 July 1994, Prague, Czech Republic.
International journal of systematic and evolutionary microbiology. 06/2000; 50 Pt 3:1391-2.
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0.63Impact points
In vitro colonisation of acrylic resin denture base materials by Streptococcus oralis and Actinomyces viscosus.
International dental journal. 05/2000; 50(2):79-85.
AIM: The aim of the study was to compare the attachment of two typical strains of oral bacteria to four denture base materials. DESIGN: In vitro study. METHOD: Discs of acrylic resin denture base materials (Paladon 65, polished and unpolished; Palapress; Microbase, polished and unpolished, and Triad... [more] AIM: The aim of the study was to compare the attachment of two typical strains of oral bacteria to four denture base materials. DESIGN: In vitro study. METHOD: Discs of acrylic resin denture base materials (Paladon 65, polished and unpolished; Palapress; Microbase, polished and unpolished, and Triad VLC) were placed into Petri dishes with Schaedler's medium, inoculated with Streptococcus oralis 34 or Actinomyces viscosus T14V. MAIN OUTCOME MEASURES: After 24 h or 48 h the numbers of adhering bacteria were measured. RESULTS: The bacteria adhered to all discs in similar numbers: 3-9 x 10(6)/ml (viable cell count) and 9-22 x 10(8)/ml (total cell count) for T14V, and 2-6 x 10(6)/ml (viable cell count) and 1.5-3 x 10(8)/ml (total cell count) for 34. CONCLUSIONS: Polishing had little effect on adherence. Denture base materials are not resistant against adherence and possible surface damage by oral bacteria. Therefore, thorough oral hygiene is important for denture wearers.
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Birgül Azrak
Johannes Gutenberg-University
