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Dentists` Involvement in Applying the New Early Childhood Preventive Procedures In Different German States
Get PDFBackground:
Early childhood caries is one of the most relevant problems that could
interfere with the children's quality of life and their general health. Early caries prevention could be a key solution to reduce caries development in children.
Aim:
Early childhood caries is one of the most relevant problems that interferes with children’s quality of life and sometimes their general health. Prevention could be a key solution to reduce caries development in children. Therefore, the aim of this study was to assess the involvement of specialists in pediatric dentistry and the non-specialists in Germany in early dental prevention, the frequency of different preventive procedures as well as the difficulties in performing them. Furthermore, the study aimed to assess if there are potentially significant differences between specialists and non-specialists.
Materials and Methods:
A questionnaire was designed and distributed in both online and analog version with 5-point Likert scales. 6 German states were included in this study. Both descriptive and statistical analysis (t-test) were made to evaluate the gradual approval or rejection to the different Statements and eventually to compare between both specialists (PD) and non-specialists (GD) in pediatric dentistry. Data were collected anonymously.
Results:
511 questionnaires meet the inclusion criteria and included in the study (mean age 47±11 year, 63.8% females, 36.7% PD). GD and PD recommended diagnostic dental visit routinely (1= never, 5= always; GD: mean 3.6±1.2, PD: 4.0±1.1; p<0.01), while parental oral hygiene training on their own children seems to be done more by PD (GD: mean 2.7±1.2, PD: 3.4±1.2; p<0.01). PD recommended tooth brushing with fluoridated toothpaste after first tooth eruption significantly more often than GD (GD: mean 3.9±1.4, PD: 4.1±1.2; p=0.03). Amazingly fluoride-free toothpaste was also recommended by a relevant number (GD: mean 1.7±1.3, PD: 1.8±1.3; p=0.9). Little cooperation of the child during the examination was the main problem for dentists in both group with 58.7%. Conclusion: GD in participants German states seem to have been engaged in the prevention of early childhood caries, even before the introduction into the National Health System, which was topped by dentists with special training in pediatric dentistry
Investigation of real-life drug intake behaviour in older adults and geriatric patients in Northern Germany – A biopharmaceutical perspective
Get PDFDosing conditions (type and amount of accompanying fluid, the type of food, the time of administration, and dosage form modifications such as crushing tablets) are critical and affect the performance of oral dosage forms in the gastrointestinal tract and thus bioavailability. Because older adults are the primary users of medications and are more susceptible to adverse effects, it is important to understand how they take their medications in order to reduce risks and increase benefits of the pharmacotherapy. The aim of the study was to investigate the real-life drug intake behaviour in geriatric patients and older adults and discuss their influence on drug absorption after oral administration. The data from two settings home vs. hospital and genders women vs. men were presented. A questionnaire study was performed among people aged at least 65 years from two settings (hospital vs. home), recruited mostly from community pharmacies and a regional hospital in Mecklenburg – Western Pomerania. The obtained data demonstrates that older adults and geriatric patients take their medications in the same way regardless of the setting and gender. There were no significant differences. Interviewed participants were mostly adherent to the doctor's recommendations and mostly took their medications in the same way every day. Medications are most commonly taken with a small (100 mL) or large (200 mL) glass of noncarbonated water, after food (during or after breakfast 64 % of intakes in the morning and during or after dinner 81 % of intakes in the evening). Meal usually consisted of bread, either with jam or honey (breakfast), or ham and cheese (dinner). All reported dosage form modifications were made to tablets. In almost all cases it was splitting the tablet, which was performed due to doctor's indication
Temporally transferable crop mapping with temporal encoding and deep learning augmentations
Get PDFDetailed maps on the spatial and temporal distribution of crops are key for a better understanding of agricultural practices and for food security management. Multi-temporal remote sensing data and deep learning (DL) have been extensively studied for deriving accurate crop maps. However, strategies to solve the problem of transferring crop classification models over time, e.g., training the model with data for a recent year and mapping back to the past, have not been fully explored. This is due to the lack of a generalized method for aggregating optical data with regard to the irregularity in annual clear sky observations and the scarcity of multi-annual crop reference data to support a more generalized DL model. In this study, we tackled these challenges by introducing a method namely Temporal Encoding (TE) to capture the irregular phenological information. Subsequently, we adapted and integrated two methods, i.e., Random Observations Selection (ROS) and Random Day Shifting (RDS) to simulate the variability of temporal sparsity as well as the shifts of crop phenology over different years. We tested this approach with a 1-dimensional Convolutional Neural Network (1D-CNN) and a Transformer Network models. Our results for both classifiers showed that models trained with crop reference data from 2018 and a dense time series of Landsat 7/8 and Sentinel-2 A/B data can be transferred with little decreases in accuracy to map 12 consecutive years from 2010 to 2021. The Transformer Network was slightly more accurate, while the 1D-CNN was much three times faster. Furthermore, the proposed models could achieve similar performances in the same years with and without fully available satellite information. The TE with ROS and RDS appears well suited for improving temporal transferability to support long term historic crop mapping
Predicting gastric emptying of drug substances taken under postprandial conditions by combination of biorelevant dissolution and mechanistic in silico modeling
Get PDFPhysiologically based pharmacokinetic (PBPK) models can help to understand the effects of gastric emptying on pharmacokinetics and in particular also provide a platform for understanding mechanisms of food effects, as well as extrapolation between different postprandial conditions, whether standardized clinical or patient-oriented, non-clinical conditions. By integrating biorelevant dissolution data from the GastroDuo dissolution model into a previously described mechanistic model of fed-state gastric emptying, we simulated the effects of a high-calorie high-fat meal on the pharmacokinetics of sildenafil, febuxostat, acetylsalicylic acid, theobromine and caffeine. The model was able to simulate the variability in Cmax and tmax caused by the presence of the stomach road. The main influences investigated to affect the gastric emptying process were drug solubility (theobromine and caffeine), tablet dissolution rate (acetylsalicylic acid) and sensitivity to gastric motility (sildenafil and febuxostat). Finally, we showed how PBPK models can be used to extrapolate pharmacokinetics between different prandial states using theobromine as an example with results from a clinical study being presented
Direct asymmetric synthesis of β-branched aromatic α-amino acids using engineered phenylalanine ammonia lyases
Get PDFβ-Branched aromatic α-amino acids are valuable building blocks in natural products and pharmaceutically active compounds. However, their chemical or enzymatic synthesis is challenging due to the presence of two stereocenters. We design phenylalanine ammonia lyases (PAL) variants for the direct asymmetric synthesis of β-branched aromatic α-amino acids. Based on extensive computational analyses, we unravel the enigma behind PAL’s inability to accept β-methyl cinnamic acid (β-MeCA) as substrate and achieve the synthesis of the corresponding amino acids of β-MeCA and analogs using a double (PcPAL-L256V-I460V) and a triple mutant (PcPAL-F137V-L256V-I460V). The reactions are scaled-up using an optimized E. coli based whole-cell biotransformation system to produce ten β-branched phenylalanine analogs with high diastereoselectivity (dr > 20:1) and enantioselectivity (ee > 99.5%) in yields ranging from 41-71%. Moreover, we decipher the mechanism of PcPAL-L256V-I460V for the acceptance of β-MeCA and converting it with excellent stereoselectivity by computational simulations. Thus, this study offers an efficient method for synthesizing β-branched aromatic α-amino acids
Individual use of self-medication and other remedies in COVID-19 outpatients in Western-Pomerania
Get PDFWe analyzed data from positively tested COVID-19 outpatients to describe self-medication with OTC drugs and use of other remedies against symptoms of SARS-CoV-2 infection. We specifically considered their type and frequency, as well as associations with patient characteristics, and reasons for use. Data were collected between May 1, 2020 and February 22, 2021 with two questionnaires in an observational cohort study with PCR-confirmed SARS-CoV-2-positive adult outpatients in the district of Western Pomerania in Germany. 523 out of 710 outpatients (74%; 340 women and 183 men) reported using drugs and other remedies to relieve COVID-19-symptoms. Overall, participants reported utilization of 1282 finished dosage products or remedies, including 213 different ingredients. In the population of 710 outpatients, utilization of ibuprofen (26%), acetaminophen (21%), metamizole (14%), and acetylsalicylic acid (10%) was most commonly reported. Phytopharmaceuticals, herbal and animal products as well as vitamins and minerals were also frequently reported. Among the 523 participants who used drugs and other remedies, most commonly mentioned reasons for use were headache (40%), other kinds of pain (e.g. myalgia; 37%), fever (24%) and cough (16%). Our analysis showed that a majority of the participants tried to alleviate COVID-19-symptoms using drugs and other remedies. Especially analgesic and antipyretic agents, followed by herbal medicines, were used very frequently. Trial registration: German Register for Clinical Studies DRKS00021672, first registration on December 1st, 2020
Impact of Maternal Pre-Pregnancy Underweight on Cord Blood Metabolome: An Analysis of the Population-Based Survey of Neonates in Pomerania (SNiP)
Get PDFIntrauterine growth restriction leads to an altered lipid and amino acid profile in the cord blood at the end of pregnancy. Pre-pregnancy underweight is an early risk factor for impaired fetal growth. The aim of this study was to investigate whether a pre-pregnancy body mass index (ppBMI) of <18.5 kg/m 2 , as early as at the beginning of pregnancy, is associated with changes in the umbilical cord metabolome. In a sample of the Survey of Neonates in Pomerania (SNIP) birth cohort, the cord blood metabolome of n = 240 newborns of mothers with a ppBMI of <18.5 kg/m 2 with n = 208 controls (ppBMI of 18.5–24.9 kg/m 2 ) was measured by NMR spectrometry. A maternal ppBMI of <18.5 kg/m 2 was associated with increased concentrations of HDL4 cholesterol, HDL4 phospholipids, VLDL5 cholesterol, HDL 2, and HDL4 Apo-A1, as well as decreased VLDL triglycerides and HDL2 free cholesterol. A ppBMI of <18.5 kg/m 2 combined with poor intrauterine growth (a gestational weight gain (GWG) < 25th percentile) was associated with decreased concentrations of total cholesterol; cholesterol transporting lipoproteins (LDL4, LDL6, LDL free cholesterol, and HDL2 free cholesterol); LDL4 Apo-B; total Apo-A2; and HDL3 Apo-A2. In conclusion, maternal underweight at the beginning of pregnancy already results in metabolic changes in the lipid profile in the cord blood, but the pattern changes when poor GWG is followed by pre-pregnancy underweight
Construction of biocompatible and electrically conductive coatings consisting of carbon nanotubes and polyelectrolytes
Get PDFThe combination of the Layer-by-Layer (LbL) method, a nano-material such as carbon nanotubes (CNTs), and charged polyelectrolytes (PEs) is a reliable approach to produce highly functionalized surface coatings. These coatings are stable, controllable, ultra-thin, and most importantly, biocompatible. The ability to tune their properties by varying the preparation conditions and the terminating layer opens up a wide range of applications in the fields of biology and medicine. Here, the goal was to create electrically conductive coatings on which cells grow and proliferate. To achieve this goal, a coating with a stable conductive film structure, a suitable film surface topography, and suitable surface potential (and -potential) must be prepared.
At the beginning of this thesis, the focus was on the fabrication of electrically conductive multilayer films, whose electrical properties should be stable and adjustable in a controlled manner (Article 1). The combination of chemically modified CNTs as polyanions, a strong linear polycation like poly(diallyldimethylammonium chloride) (PDADMA), and the LbL-method allowed us to prepare such films. Their characterization was carried out in air at ambient conditions. Since PDADMA is non-conductive, the charge transfer within the film and thus the electrical conductivity itself depends mainly on the CNTs and their arrangement. It was found that four CNT/PDADMA bilayers (BL) were always necessary to create a lateral network structure with multiple CNT crossing points to enable and support electron transport within the film. Moreover, additional CNT/PDADMA BL resulted in decreasing sheet resistance, while the conductivity remained constant at ≈ 4 kS/m regardless of the number of bilayers. Increasing the PDADMA molecular weight (Mw) from 44.4 kDa to 322 kDa did not affect film properties such as thickness or electrical conductivity.
However, increasing the CNT concentration from 0.15 mg/ml to 0.25 mg/ml in the deposition suspension resulted in thicker and less conductive films. This is attributed to a faster adsorption process of the CNTs leading to more adsorption sites for the polycation. We found an increased PDADMA monomer/CNT ratio compared to films prepared with the lower CNT concentration in the deposition suspension. The electrical conductivity decreased by a factor of four down to 1.1 kS/m, which can be attributed to fewer contact points between the CNTs. Overall, we were able to prepare stable and electrically conductive multilayer films. Additionally, by varying the preparation conditions tuning of the electrical conductivity is possible.
To fulfill requirements regarding i.e., medical implants, film properties not only have to be stable and controllable in a dry state (described in Article 1) but also in a biological aqueous environment. Therefore, in Article 2 we immersed our coated samples in three different solutions usually employed in biological research and compared their properties with their dry state, respectively. Also, hydration/swelling effects that normally occur for polyelectrolyte multilayer films (PEMs) in solutions were investigated.
For the film preparation, PDADMA (Mw = 322 kDa) and a deposition suspension of modified CNTs with two different concentrations (0.15 mg/ml and 0.25 mg/ml), which aged for two years, were used. Independent of the CNT suspension concentration, it turned out that the film thickness of the samples, prepared from the aged suspension, decreased significantly compared to the film thickness previously measured in Article 1. As a cross-check a new and fresh CNT suspension was made, which allowed us to reproduce the film thickness described in Article 1.
These results indicated that something happened with the CNT suspension over a two-year period. An analysis via X-ray photoelectron spectroscopy (XPS) showed a decrease in the percentage of functional groups in the CNTs from the aged suspension. The loss of functional groups resulted in less negatively charged CNTs and thus in fewer adsorption sites for the polycation PDADMA. Consequently, the PDADMA monomer/CNT ratio decreased, which lowered the thickness per bilayer by a factor of three, compared to films prepared with a freshly prepared CNT suspension. The lower linear charge density of the aged CNTs also enhanced their hydrophobicity, which is, in combination with the electrostatic forces, another important factor for multilayer cohesion. In contrast to PEMs made from polycations and polyanions, no swelling of the films occurred when immersed in solutions. This can be attributed to the fact that the increased hydrophobicity of the CNTs and the hydrophobic nature of the PDADMA backbone prevent the incorporation of water into the multilayer film. In solution, the films slightly shrink (by ≈ 2 nm), which makes them even more compact. Yet they remain stable. The result is an increased electrical conductivity from 9.6 kS/m, in the dry state, up to 15.3 kS/m immersed in solutions. To summarize, we showed that by tuning the interpolyelectrolyte forces the swelling and the ensuing decrease of the electrical conductivity of the films can be prevented.
Regarding the application in biology and medicine, we must consider that long-term exposure of cells to nano-materials like CNTs could lead to damage and inflammation of adjacent tissue. Therefore, it is necessary to prevent direct contact between the electrically conductive multilayer, i.e., CNT/PDADMA film, and the cells. The solution to this problem is a biocompatible top film that covers the CNT/PDADMA multilayer completely and still provides a lateral surface structure that supports cell adhesion and proliferation. Additional layers consisting solely of PEs could provide such a top film.
In Article 3 we investigated the self-patterning of PEM films as function of deposition steps. After preparation in water, the films were dried, characterized in air, and in vacuum. The films were built with high and low molecular weight PEs. PDADMA was used as polycation and poly(styrene sulfonate) sodium salt (PSS) as polyanion. The observation via Atomic Force Microscopy (AFM) showed that films prepared with high molecular weight PEs are laterally homogeneous and form no patterns, due to the chain immobility. The flat surfaces are ineligible as a substrate for cell adhesion.
In contrast, films built with a short PSS, especially at Mw, PSS = 10.7 kDa, began to self-pattern after seven deposited PDADMA/PSS bilayers. With each additionally deposited bilayer, the surface got more and more structured, from grooves over stripes to circular domains. Increasing film thickness led to an increased lateral mean distance between the surface structures. Scanning Electron Microscopy (SEM) images showed that exposure to a vacuum resulted in a decrease in the film thickness attributed to water removal, while the mean distance between the domains increased. Thus, by using this self-pattering process we are able to prepare PEMs with a highly structured surface. By adding PDADMA/PSS bilayers, not only the CNT/PDADMA film can be covered completely, but also a suitable surface morphology for cells can be created. Controlling the number of deposited bilayers allows the preparation of suitable coatings for cells.
To further improve the interaction of the cell and coated substrate not only the lateral structure but also the interacting electrostatic forces between cells and substrate are important for the nature of cell adhesion, function, and proliferation. In Article 4 we investigated PEMs, consisting of strong PEs with a low (PDADMA) and high (PSS) linear charge density. We performed asymmetric force measurements with the help of the colloidal probe technique (CP). Here, the forces between a PEM-covered surface and a colloidal probe (silica sphere) glued to a cantilever were investigated. The colloidal probe was either bare or covered with polycation poly(ethylenimine) (PEI). The surfaces were immersed in NaCl solutions with different ionic strengths (INaCl), starting with deionized water, then enriched up to 1 mol/L NaCl. The interaction force between a CP and the surface was measured. Thus, insight into the surface potential/charge was obtained.
During film preparation, two growth regimes (parabolic and linear) exist. These regimes and the terminating layer determine the surface force of the PEM. PEMs with a terminating PSS layer are predominantly flat and negatively charged when the ion concentration is low and the film is in the parabolic growth regime (between 1 and ≈ 15 BL). This indicates charge reversal on PSS adsorption. At the transition point between the parabolic and linear growth regimes, the ratio between polyanion and polycation monomers starts to switch and some cationic monomers are neutralized not by anionic monomers but by monovalent ions. Therefore, the surface charge density in diluted NaCl solutions changed from slightly positive near the transition to positive in the linear growth regime. At the lowest ionic strengths (INaCL) the range of the surface potential goes from – 40.5 mV (9 BL, parabolic) up to + 50 mV (19 BL, linear).
In contrast, polycation (PDADMA) terminated films are overall positive in diluted NaCl solutions. At the beginning of the parabolic growth regime, the layers are more compact and flat. However, with each additional layer deposited, the film becomes less compact and the chains begin to loosen. The now more loosely bound chains start to protrude into the solution and form pseudo-brushes. This could already be observed for 10.5 BL.
It intensifies in the linear growth regime (begin at ≈ 15 BL) and results in steric surface forces. Changing the surrounding INaCl affects this behavior and the pseudo-brushes scale as polyelectrolyte brushes.
By controlling the number of bilayers (thus the growth regime), the surrounding ionic strength, and the conformation of PEs at the PEM surface, it is possible to prepare a suitable range of surface properties i.e., for cell adhesion and proliferation. To prove that these multilayers can provide a suitable surface and have a positive effect on cell behavior, we coated in Article 5 titanium-covered samples with PEMs. Investigated was the cell interaction with the surface at different zeta(ζ) - potentials, a parameter for dynamic surface potential. Here the cell activity is measured by the mobilization of calcium (Ca2+) within the cell as a function of the ζ - potential of the substrate and the externally applied electrical potential. The cell activity indicates if the ζ - potential, provided by the sample surface, is suitable or not for the cells. The favorable interaction with the substrate is also reflected in the cell morphology and proliferation. The results showed that highly negative ζ - potentials between - 90 and - 3 mV led to a decreasing/reduced Ca2+ mobilization which correlates with reduced cell activity. Nearly neutral to moderate positive surfaces (ζ - potential + 1 to + 10 mV) i.e., PSS-terminated PEMs are able to promote cell adhesion and growth as demonstrated by an increased Ca2+ mobilization. The access to the intracellular Ca2+ stores, provided by the external stimulus, is now more effective and suggests a higher cell activity. Increasing the ζ - potentials up to ≈ + 50 mV (highly positive), i.e., PDADMA - terminated PEMs with pseudo-brushes, resulted in restricted cell viability and impaired Ca2+ mobilization, which led to a disturbed cell morphology and proliferation. In conclusion, only surfaces, terminated with i.e., PEI, with moderate positive charges (ζ - potential + 1 to + 10 mV) are able to improve the Ca2+ mobilization and thus the cell activity and proliferation. PEMs with a PSS termination provide negative −potentials, onto which cells adhere, and proliferate. Therefore, they are a good alternative for surface functionalization for implant surfaces. In summary, the objective set at the beginning of the thesis is addressed within articles written as part of this thesis. It is possible to fabricate PEMs with modified CNTs to produce coatings that are electrically conductive with tunable sheet resistance, whether dry in air or immersed in an aqueous solution (Articles 1 and 2). Also, for pure PEMs, it is shown that with the right molecular weight of PEs and a certain number of bilayers, a suitable surface structure for cell adhesion can be produced (Article 3). Additional surface properties such as a suitable surface charge density can be provided by PEMs which can improve the cell activity as monitored with Ca2+ mobilization (Articles 4 and 5). The next step is to combine the knowledge gained from Articles 1 – 5 and link it to the application of external electrical fields to cells
Weltdarstellungen in Text und Bild in Drucken zwischen 1450 und 1500
Get PDFDie Untersuchung widmet sich der Analyse von Darstellungen von Erde und Kosmos in ausgewählten Drucken der Inkunabelzeit zwischen 1450 und 1500. Das Forschungskorpus umfasst verschiedene Werke, darunter das „Buch der Natur“ von Konrad von Megenberg, den „Lucidarius“, den „Schatzbehalter“ von Stephan Fridolin und die „Weltchronik“ Hartmann Schedels. Im Fokus steht die Untersuchung des Verhältnisses von Text und Bild sowie der Funktionen der Holzschnitte bei der Vermittlung von Wissen über die Welt. Bei der Analyse werden Aspekte wie Layout, Bildformeln, Kolorierung und das Zusammenspiel von Text und Bild bei der Rezeption berücksichtigt. Die Werke repräsentieren unterschiedliche Textgattungen und ermöglichen Einblicke in die sich wandelnde Rezeption von Wissen über Erde und Kosmos im Übergang von der Handschrift zum Druckmedium
Untersuchungen zum Färbeverhalten von Zahnoberflächen nach Anwendung unterschiedlicher Prophylaxepulver. Eine in-vitro Studie an extrahierten Zähnen
Get PDFEin wichtiges Nachsorgekonzept nach erfolgter Parodontitistherapie besteht im Angebot einer Unterstützdenden Parodontitis Therapie (UPT). Hierfür stehen herkömmliche Methoden wie Hand-, Schall- und Ultraschallinstrumente einerseits sowie Luft-Pulver-Wasserstrahlgeräte andererseits zur Verfügung.
Die vorliegende Arbeit untersucht in diesem Kontext einen spezifischen Aspekt der Luft-Pulver-Wasserstrahltechnik. Es soll betrachtet werden, welche Wirkung niedrig-abrasive Prophylaxepulver auf die Farbstabilität von Zahnschmelz haben und wie dieser Effekt sich im Vergleich zu herkömmlicher Zahnpolitur mit Polierpaste darstellt. Ein weiterer Beitrag der Studie besteht in der eigenständigen Entwicklung eines in-vitro Modells, in dem das Färbeverhalten von Zahnoberflächen reproduzierbar erfasst werden kann.
Insgesamt liegen aus dieser Untersuchung Daten von 152 extrahierten Zähnen vor, welche durch verschiedene Verfahren oberflächlich behandelt und anschließend in eine Färbelösung aus Kaffee gegeben wurden. Die Zahnfarben wurden zu verschiedenen Zeitpunkten mittels digitaler Bildanalyse bestimmt.
Im gewählten Versuchsaufbau (Durchlauf 1 und 2) ließ sich zunächst kein signifikanter Unterschied im Färbeverhalten nach Behandlung mit den Prophylaxepulvern Airflow Plus, Airflow Perio (EMS, Nyon, Schweiz) oder der Polierpaste Cleanic Prophy Paste flouride (Kerr Hawe, Bioggio, Schweiz) feststellen. Die Anwendung der verglichenen drei Produkte nach Herstellerangaben in der Studiensimulation erbrachte demnach keine signifikanten Verfärbungsunterschiede. Erst eine Modifikation des Versuchsablaufs im 3. Durchlauf, bei welchem die Zahnproben zusätzlich mit einer gesättigten Lösung aus Prophylaxemittel und Aqua Dest exponiert wurden, konnte einen signifikanten Einfluss des Prophylaxepulvers Airflow Plus auf das Färbeverhalten zeigen. Es ist von einem chemischen Einfluss des Inhaltsstoffes Chlorhexidin im Pulver Airflow Plus auszugehen, welcher in einer Konzentration von ≤0,3% im Pulver enthalten ist.
Diese Nebenwirkung ist aus der Praxis und aus der Literatur bekannt und wurde bereits in zahlreichen Untersuchungen bestätigt.
Gegenstand zukünftiger Arbeiten könnte die Untersuchung des Einflusses des Hauptbestandteils Erythritol auf das Färbeverhalten von Zahnoberflächen sein, oder der Einfluss höherer Druck- und Wassereinstellungen des Prophylaxegerätes. Des weiteren könnte ein Einfluss speziell auf das Färbeverhalten von Dentin oder Kompositrestaurationen durch das Prophylaxepulver EMS Airflow Plus und seine einzelnen Bestandteile untersucht werden