scholarly journals The Effects of Three Remineralizing Agents on the Microhardness and Chemical Composition of Demineralized Enamel

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6051
Author(s):  
Ivan Salinovic ◽  
Zdravko Schauperl ◽  
Marijan Marcius ◽  
Ivana Miletic

This study aimed to determine the effects of three different varnish materials (containing casein phosphopeptide-amorphous calcium phosphate, nano-hydroxyapatite, and fluoride) on enamel. Thirty-three extracted human third molars were used for specimen preparation. These were demineralized using phosphoric acid. Three experimental groups (n = 11) were treated with 3M™ Clinpro™ White Varnish, MI Varnish®, and Megasonex® toothpaste, respectively, every twenty-four hours for fourteen days. Analysis of the microhardness of the specimens’ enamel surfaces was carried out via the Vickers method, and by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Analysis was performed at three stages: at baseline value, after demineralization, and after the period of remineralization. Data were subjected to Scheffe’s post hoc test. The mean microhardness values (HV0.1) obtained for the group of samples treated with MI Varnish® were higher compared with the other two groups (p = 0.001 for both comparisons), while the first and third groups did not differ significantly from each other (p = 0.97). SEM analysis showed uneven patterns and porosities on all samples tested. EDS results showed an increase in the mineral content of the examined samples, with the highest mineral content observed in the MI Varnish® group. It can be concluded that MI Varnish® use has a better remineralization effect on enamel than the other two materials.

2017 ◽  
Vol 41 (4) ◽  
pp. 275-279 ◽  
Author(s):  
Eda Arat Maden ◽  
Özge Acar ◽  
Ceyhan Altun ◽  
Günseli Güven Polat

Objective: This study aimed to investigate the effect of acidulated phosphate fluoride (APF) gel and casein phosphopeptide/amorphous calciumphosphate (CPP-ACP) on the dental erosion produced by carbonated soft drink in primary teeth. Study Design: This study evaluated by an in vitro model the effect of APF gel and CPP-ACP on the dental enamel previously subjected to erosive challenge with carbonated soft drink. Sixty sound human primary molars were prepared by embedding the crown sections in acrylic resin blocks leaving the enamel surfaces exposed. The surface roughness of the enamel was measured with prophilometry at baseline. Specimens were randomly divided into three treatment groups (n:20): artificial saliva, CPP-ACP, 1.23% APF gel. All specimens were then exposed to an erosive challenge of carbonated soft drink and artificial saliva for 20 cycles of 20 seconds each. Demineralization-remineralization cycles was repeated twice at eight-hour intervals and roughness values were measured. Enamel samples were treated with artificial saliva, CPP-ACP, 1.23% APF gel applied for 10 min after erosive challenge. The arithmetic average roughness (Ra) readings were recorded after remineralization agents were applied. Results: The mean surface roughness in all groups increased significantly after erosion process and decreased after remineralization treatment. After treatment, the mean surface roughness of the 1.23% APF gel group was significantly less than the other groups and the mean surface roughness of the artificial saliva group was significantly more than the other groups. 1.23% APF gel showed the highest protective effect against erosive enamel loss. Conclusions: Under the conditions of this study, artificial saliva, CPP-ACP and 1.23% APF treatments were able to reduce erosive enamel loss produced by carbonated soft drink in primary teeth. However, 1.23% APF gel showed the highest protective effect against erosive enamel loss.


2005 ◽  
Vol 19 (4) ◽  
pp. 256-260 ◽  
Author(s):  
Maria Francisca Thereza Borro Bijella ◽  
Fernanda Lourenção Brighenti ◽  
Maria Fernanda Borro Bijella ◽  
Marília Afonso Rabelo Buzalaf

There is a relationship between the use of fluoride, the reduction of dental caries and the increase of dental fluorosis. The purpose of this study was to analyze the fluoride kinetics in saliva after using the HappydentTM chewing gum, which contains 3.38 mg of fluoride as monofluorophosphate. Fifteen 7-9-year-old volunteers were instructed to chew the gum TridentTM (control) and HappydentTM on different days. Total saliva was collected for 3 minutes, at 0, 3, 6, 9, 15, 30 and 45 minutes after starting chewing. Salivary fluoride was analyzed with a fluoride-specific electrode (Orion 96-09) after acid hydrolysis. The data were analyzed by two-way analysis of variance and by Tukey’s post hoc test (p < 0.05). The mean amounts ± sd (mg) of fluoride released in saliva were 0.276 ± 0.126 and 0.024 ± 0.014 for HappydentTM and TridentTM respectively. The fluoride amount in the saliva samples after the use of Happydent was significantly higher than after the use of TridentTM in all experimental periods, except after 30 and 45 minutes. The high fluoride presence in saliva after the use of Happydent may be significant to prevent dental caries and this should be evaluated in clinical researches. On the other hand, children at an age of risk for dental fluorosis should avoid the use of HappydentTM.


2001 ◽  
Vol 13 (3) ◽  
pp. 151 ◽  
Author(s):  
Takeshige Otoi ◽  
Aya Ooka ◽  
Masako Murakami ◽  
N.W. Kurniani Karja ◽  
Tatsuyuki Suzuki

The present study was conducted to examine the effects of the stage of the oestrous cycle on the meiotic competence of canine oocytes and also to investigate the relationship between the stage of the oestrous cycle and the relative size distribution of oocytes obtained from bitches at three stages of the cycle (anoestrus, follicular phase and dioestrus). Only healthy-looking cumulus–oocyte complexes were used for in vitro maturation and these were divided into three groups based on diameter (<110, 110 to <120 and ≥120 µm). The mean diameter of oocytes from ovaries at anoestrus, the follicular phase and dioestrus was 103.6, 119.2 and 107.7 µm, respectively. The percentage of large oocytes (120 µm) collected at the follicular phase was higher (P<0.01) than that collected at dioestrus and the percentage of oocytes ≥120 µm collected from ovaries at dioestrus was higher (P<0.01) than that collected at anoestrus. After culture for 72 h, significantly more oocytes reached metaphase II (MII) in the follicular phase than in the other stages (P<0.01), and more oocytes reached MII in dioestrus than in anoestrus (P<0.05). In the ≥120 µm group, the frequency of oocytes that resumed meiosis in the follicular phase was higher (P<0.05) than in the other stages. However, in the smaller diameter (<120 µm) groups, there were no significant differences between ovaries at different stages of the oestrous cycle with respect to the proportion of oocytes reaching each stage of meiosis. Thus, the oestrous cycle stage influences maturation frequency. Moreover, oocytes demonstrated a size-related ability to undergo meiotic maturation, irrespective of the stage of the oestrous cycle. These results suggest that the effects of the stage of the oestrous cycle may result from differences in the distribution of large oocytes.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 792.1-792
Author(s):  
P. J. Mease ◽  
L. C. Coates ◽  
F. Van den Bosch ◽  
D. D. Gladman ◽  
L. Gheyle ◽  
...  

Background:Psoriatic arthritis (PsA) is a heterogeneous, inflammatory disease involving multiple clinical domains including arthritis/synovitis, enthesitis, dactylitis, spondylitis and psoriasis. Effects on each domain should be assessed to determine the overall quality of treatment. Filgotinib (FIL) is a novel preferential Janus kinase 1 inhibitor that is in development for inflammatory conditions including PsA. EQUATOR (NCT03101670) was a 16-week, Phase 2, double-blind, randomised, placebo (PBO)-controlled trial of FIL for patients with active PsA.1 EQUATOR2 (NCT03320876) is an open-label extension (OLE) of the study.Objectives:This post-hoc analysis of EQUATOR and EQUATOR2 assessed the patient-level correlation between changes over time in the three PsA clinical disease domains of skin, joint and enthesitis in patients treated with FIL.Methods:In EQUATOR, patients with active moderate-to-severe PsA (≥5 swollen joints and ≥5 tender joints, fulfilling Classification for PsA criteria) were randomised 1:1 to receive oral FIL 200 mg or PBO once daily (QD) for 16 weeks. At Week 16, patients could continue into the 304-week OLE, with all patients receiving FIL 200 mg QD regardless of previous treatment in EQUATOR. This post-hoc analysis was limited to patients with skin involvement (≥3% body surface area), joint involvement and enthesitis at baseline, with changes from baseline in the three domains assessed using the Psoriasis Area and Severity Index (PASI), swollen/tender joint count (S/TJC), and the Leeds Enthesitis Index (LEI) and Spondyloarthritis Research Consortium of Canada (SPARCC) index, respectively. Analyses that used LEI as the enthesitis index to assess change from baseline included patients with LEI score ≥1 at baseline; those using SPARCC included patients with SPARCC score ≥1 at baseline.Results:The EQUATOR study enrolled 131 patients and 122 patients continued into the EQUATOR2 OLE. Of the 131 patients enrolled in EQUATOR, 49 and 56 patients had PsA involving all three domains at core study baseline when enthesitis was assessed using LEI and SPARCC index, respectively. Pooled data for all patients receiving FIL during the OLE indicate that improvements from baseline in the clinical domains continued with long-term treatment, with 22/42 (52%) and 23/38 (61%) patients having both SJC66 and LEI resolution at Weeks 52 and 100, respectively. For the 22 patients with both SJC and LEI resolution at Week 52, the mean percent change from baseline for PASI was –64%; for the 23 patients with both SJC and LEI resolution at Week 100, the mean percent change from baseline for PASI was –60%. The Figure 1 shows correlation between SJC, LEI and PASI at Week 100. A relationship between the three clinical domains was observed at the individual level; within a single patient, an improvement in one domain was generally followed by improvements in the other two domains. With regard to the sequence in which changes were observed, joints improved first, followed by improvements in the skin and enthesitis. There were no notable differences between changes in LEI and SPARCC enthesitis index in terms of their correlation with improvements in joint and skin involvement. Similarly, there were no notable differences in correlation between the three domains when joints were assessed using TJC rather than SJC.Conclusion:Patients with improvements in skin, joints or enthesitis following treatment with FIL generally also had improvements in the other clinical domains of PsA. The joints were found to be the first of the three domains to improve.References:[1]Mease P et al. Lancet 2018;392:2367–77Acknowledgements:EQUATOR and EQUATOR2 were sponsored by Galapagos NV (Mechelen, Belgium) and co-funded by Galapagos NV and Gilead Sciences, Inc (Foster City, CA, USA). Medical writing/editorial support was provided by Debbie Sherwood, BSc, CMPP (Aspire Scientific, Bollington, UK), funded by Galapagos NV.Disclosure of Interests:Philip J Mease Speakers bureau: AbbVie, Amgen, Eli Lilly, Janssen, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol-Myers Squibb, Eli Lilly, Galapagos, Gilead Sciences, GlaxoSmithKline, Janssen, Novartis, Pfizer, SUN and UCB, Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Eli Lilly, Galapagos, Gilead Sciences, Janssen, Novartis, Pfizer, SUN and UCB, Laura C Coates Speakers bureau: AbbVie, Amgen, Biogen, Celgene, Eli Lilly, Gilead, Janssen, Medac, Novartis, Pfizer and UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Eli Lilly, Gilead, Janssen, Novartis, Pfizer and UCB, Grant/research support from: AbbVie, Amgen, Celgene, Eli Lilly, Novartis, and Pfizer, Filip van den Bosch Consultant of: AbbVie, Celgene, Eli Lilly, Galapagos, Gilead, Janssen, Merck, Novartis, Pfizer, and UCB, Grant/research support from: AbbVie, Merck and UCB, Dafna D Gladman Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, Pfizer, and UCB, Grant/research support from: AbbVie, Amgen, Celgene, Eli Lilly, Janssen, Novartis, Pfizer and UCB, Lien Gheyle Shareholder of: Galapagos, Employee of: Galapagos, Mona Trivedi Shareholder of: Gilead Sciences, Amgen, Employee of: Gilead Sciences, Muhsen Alani Shareholder of: Gilead Sciences, Employee of: Gilead Sciences, Eline Vetters Employee of: Galapagos, Franck Olivier Le Brun Shareholder of: Galapagos, Employee of: Galapagos, Robin Besuyen Shareholder of: Galapagos, Employee of: Galapagos, Philip Helliwell Speakers bureau: Janssen and Novartis, Paid instructor for: Pfizer, Consultant of: Eli Lilly.


2016 ◽  
Vol 138 (8) ◽  
Author(s):  
Hakim Mecheri ◽  
Xavier Robert-Lachaine ◽  
Christian Larue ◽  
André Plamondon

The aim of this study was to evaluate eight methods for aligning the orientation of two different local coordinate systems. Alignment is very important when combining two different systems of motion analysis. Two of the methods were developed specifically for biomechanical studies, and because there have been at least three decades of algorithm development in robotics, it was decided to include six methods from this field. To compare these methods, an Xsens sensor and two Optotrak clusters were attached to a Plexiglas plate. The first optical marker cluster was fixed on the sensor and 20 trials were recorded. The error of alignment was calculated for each trial, and the mean, the standard deviation, and the maximum values of this error over all trials were reported. One-way repeated measures analysis of variance revealed that the alignment error differed significantly across the eight methods. Post-hoc tests showed that the alignment error from the methods based on angular velocities was significantly lower than for the other methods. The method using angular velocities performed the best, with an average error of 0.17 ± 0.08 deg. We therefore recommend this method, which is easy to perform and provides accurate alignment.


1993 ◽  
Vol 69 (01) ◽  
pp. 035-040 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina

SummaryFour thromboplastin reagents were tested by 18 laboratories in Europe, North-America, and Australasia, according to a detailed protocol. One thromboplastin was the International Reference Preparation for ox brain thromboplastin combined with adsorbed bovine plasma (coded OBT/79), and the second was a certified reference material for rabbit brain thromboplastin, plain (coded CRM 149R). The other two thromboplastin reagents were another rabbit plain brain thromboplastin (RP) with a lower ISI than CRM 149R and a rabbit brain thromboplastin combined with adsorbed bovine plasma (RC). Calibration of the latter two reagents was performed according to methods recommended by the World Health Organization (W. H. O.).The purpose of this study was to answer the following questions: 1) Is the calibration of the RC reagent more precise against the bovine/combined (OBT/79) than against the rabbit/plain reagent (CRM 149R)? 2) Is the precision of calibration influenced by the magnitude of the International Sensitivity Index (ISI)?The lowest inter-laboratory variation of ISI was observed in the calibration of the rabbit/plain reagent (RP) against the other rabbit/plain reagent (CRM 149R) (CV 1.6%). The highest interlaboratory variation was obtained in the calibration of rabbit/plain (RP) against bovine/combined (OBT/79) (CV 5.1%). In the calibration of the rabbit/combined (RC) reagent, there was no difference in precision between OBT/79 (CV 4.3%) and CRM 149R (CV 4.2%). Furthermore, there was no significant difference in the precision of the ISI of RC obtained with CRM 149R (ISI = 1.343) and the rabbit/plain (RP) reagent with ISI = 1.14. In conclusion, the calibration of RC could be performed with similar precision with either OBT/79 or CRM 149R, or RP.The mean ISI values calculated with OBT/79 and CRM 149R were practically identical, indicating that there is no bias in the ISI of these reference preparations and that these reference preparations have been stable since their original calibration studies in 1979 and 1987, respectively.International Normalized Ratio (INR) equivalents were calculated for a lyophilized control plasma derived from patients treated with oral anticoagulants. There were small but significant differences in the mean INR equivalents between the bovine and rabbit thromboplastins. There were no differences in the interlaboratory variation of the INR equivalents, when the four thromboplastins were compared.


1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.


1985 ◽  
Vol 54 (04) ◽  
pp. 739-743 ◽  
Author(s):  
Federica Delaini ◽  
Elisabetta Dejana ◽  
Ine Reyers ◽  
Elisa Vicenzi ◽  
Germana De Bellis Vitti ◽  
...  

SummaryWe have investigated the relevance of some laboratory tests of platelet function in predicting conditions of thrombotic tendency. For this purpose, we studied platelet survival, platelet aggregation in response to different stimuli, TxB2 and 6-keto-PGFlα production in serum of rats bearing a nephrotic syndrome induced by adriamycin. These animals show a heavy predisposition to the development of both arterial and venous thrombosis. The mean survival time was normal in nephrotic rats in comparison to controls. As to aggregation tests, a lower aggregating response was found in ADR-treated rats using ADP or collagen as stimulating agents. With arachidonic acid (AA) we observed similar aggregating responses at lower A A concentrations, whereas at higher AA concentrations a significantly lower response was found in nephrotic rats, despite their higher TxB2 production. Also TxB2 and 6-keto-PGFlα levels in serum of nephrotic rats were significantly higher than in controls. No consistent differences were found in PGI2-activity generated by vessels of control or nephrotic rats.These data show that platelet function may appear normal or even impaired in rats with a markedly increased thrombotic tendency. On the other hand, the significance of high TxB2 levels in connection with mechanisms leading to thrombus formation remains a controversial issue.


2004 ◽  
Vol 9 (3) ◽  
pp. 233-240 ◽  
Author(s):  
S. Kim

This paper describes a Voronoi analysis method to analyze a soccer game. It is important for us to know the quantitative assessment of contribution done by a player or a team in the game as an individual or collective behavior. The mean numbers of vertices are reported to be 5–6, which is a little less than those of a perfect random system. Voronoi polygons areas can be used in evaluating the dominance of a team over the other. By introducing an excess Voronoi area, we can draw some fruitful results to appraise a player or a team rather quantitatively.


1997 ◽  
Vol 35 (2-3) ◽  
pp. 131-138 ◽  
Author(s):  
Pirjo-Riitta Rantala ◽  
Hannu Wirola

The aim of the study was to determine if solid, slightly soluble compounds can be used as nutrient source in activated sludge treatment plants instead of liquid phosphoric acid. Four different solid materials were tested in lab-scale solubility tests to find compounds which are least soluble. Two materials were chosen for further studies: apatite and raw phosphate. The use of apatite and raw phosphate as nutrient source was studied in lab-scale activated sludge reactors along with a control reactor where phosphorus was added in liquid form. The phosphorus dosage, measured as elementary phosphorus, was the same for all three reactors. The reactors were fed with pre-clarified chemi-thermomechanical pulp mill (CTMP) wastewater. There were no significant differences in the reductions of organic matter between the three reactors. The mean effluent concentration of total phosphorus was 3 mg P/l in the control reactor and less than 1 mg P/1 in the other two reactors. The soluble phosphorus concentration was more than 2 mg P/l in the control reactor and less than 0.5 mg P/l in the other two. Apatite was an even better nutrient source than raw phosphate. Further lab-scale tests were conducted using two different grain sizes of apatite. No significant differences were found between the studied grain sizes (&lt;0.074 mm and 0.074 mm-0.125 mm). Apatite was then used in full-scale at a CTMP-mill two different times. The experiments showed that the mean concentrations of phosphorus can be reduced radically by using apatite as a nutrient source instead of liquid phosphorus. Solid phosphorus compounds are a viable alternative to reduce the phosphorus load from forest industry wastewater treatment plants.


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