Nanomagnetic-Mediated Drug Delivery for The Treatment of Dental Disease

Maintaining the vitality of the dental pulp, the highly innervated and highly vascular, innermost layer of the tooth, is a critical goal of any dental procedure. Upon injury, targeting the pulp with specific therapies is challenging because it is encased in hard tissues. This project describes a method that can effectively deliver therapeutic agents to the pulp. This method relies on the use of nanoparticles that can be actively steered using magnetic forces to the pulp, traveling through naturally occurring channels in the dentin (the middle layer of the tooth). This method can reduce the inflammation of injured pulp and improve the penetration of dental adhesives into dentin. Such a delivery method would be less expensive, and both less painful and less traumatic than existing therapeutic options available for treatment of injured dental pulp. This technique would be simple and could be readily translated to clinical use

Myristyltrimethylammonium Bromide (MYTAB) as a cationic surface agent to inhibit Streptococcus mutans grown over dental resins: an in vitro study

This in vitro study evaluated the effect of myristyltrimethylammonium bromide (MYTAB) on the physical, chemical, and biological properties of an experimental dental resin. The resin was formulated with dental dimetacrylate monomers and a photoinitiator/co-initiator system. MYTAB was added at 0.5 (G0.5%), 1 (G1%), and 2 (G2%) wt %, and one group remained without MYTAB and was used as the control (GCtrl). The resins were analyzed for the polymerization kinetics, degree of conversion, ultimate tensile strength (UTS), antibacterial activity against Streptococcus mutans, and cytotoxicity against human keratinocytes. Changes in the polymerization kinetics profiling were observed, and the degree of conversion ranged from 57.36% (±2.50%) for G2% to 61.88% (±1.91%) for G0.5%, without a statistically significant difference among groups (p > 0.05). The UTS values ranged from 32.85 (±6.08) MPa for G0.5% to 35.12 (±5.74) MPa for GCtrl (p > 0.05). MYTAB groups showed antibacterial activity against biofilm formation from 0.5 wt % (p 0.05). In conclusion, the addition of 0.5 wt % of MYTAB did not alter the physical and chemical properties of the dental resin and provided antibacterial activity without cytotoxic effect

Developing a new generation of therapeutic dental polymers to inhibit oral biofilms and protect teeth

Polymeric tooth-colored restorations are increasingly popular in dentistry. However, restoration failures remain a major challenge, and more than 50% of all operative work was devoted to removing and replacing the failed restorations. This is a heavy burden, with the expense for restoring dental cavities in the U.S. exceeding $46 billion annually. In addition, the need is increasing dramatically as the population ages with increasing tooth retention in seniors. Traditional materials for cavity restorations are usually bioinert and replace the decayed tooth volumes. This article reviews cutting-edge research on the synthesis and evaluation of a new generation of bioactive dental polymers that not only restore the decayed tooth structures, but also have therapeutic functions. These materials include polymeric composites and bonding agents for tooth cavity restorations that inhibit saliva-based microcosm biofilms, bioactive resins for tooth root caries treatments, polymers that can suppress periodontal pathogens, and root canal sealers that can kill endodontic biofilms. These novel compositions substantially inhibit biofilm growth, greatly reduce acid production and polysaccharide synthesis of biofilms, and reduce biofilm colony-forming units by three to four orders of magnitude. This new class of bioactive and therapeutic polymeric materials is promising to inhibit tooth decay, suppress recurrent caries, control oral biofilms and acid production, protect the periodontium, and heal endodontic infections

Incorporation of amoxicillin-loaded microspheres in mineral trioxide aggregate cement: an <i>in vitro</i> study.

Objectives: In this study, we investigated the potential of amoxicillin-loaded polymeric microspheres to be delivered to tooth root infection sites via a bioactive reparative cement.Materials and methods: Amoxicillin-loaded microspheres were synthesized by a spray-dray method and incorporated at 2.5% and 5% into a mineral trioxide aggregate cement clinically used to induce a mineralized barrier at the root tip of young permanent teeth with incomplete root development and necrotic pulp. The formulations were modified in liquid:powder ratios and in composition by the microspheres. The optimized formulations were evaluated in vitro for physical and mechanical eligibility. The morphology of microspheres was observed under scanning electron microscopy.Results: The optimized cement formulation containing microspheres at 5% exhibited a delayed-release response and maintained its fundamental functional properties. When mixed with amoxicillin-loaded microspheres, the setting times of both test materials significantly increased. The diametral tensile strength of cement containing microspheres at 5% was similar to control. However, phytic acid had no effect on this outcome (p > 0.05). When mixed with modified liquid:powder ratio, the setting time was significantly longer than that original liquid:powder ratio (p Conclusions: Lack of optimal concentrations of antibiotics at anatomical sites of the dental tissues is a hallmark of recurrent endodontic infections. Therefore, targeting the controlled release of broad-spectrum antibiotics may improve the therapeutic outcomes of current treatments. Overall, these results indicate that the carry of amoxicillin by microspheres could provide an alternative strategy for the local delivery of antibiotics for the management of tooth infections

Avaliação do uso do Elixir de Pau’Darco como terapia complementar ao tratamento do câncer

Objective: to evaluate the follow-up of the use of Elixir of Pau D'arco (Handroanthus Avellanedae (Lorentz Ex Griseb) Mattos (Sin: Tabebuia Avellanedae Lorentz Ex Griseb) in complementary therapy to the treatment of neoplasms, produced and dispensed in the Phytotherapy Sector of the Coordination of Pharmaceutical Assistance Policies of the Health Department of the State of Ceará Methods: this is a basic, descriptive, documental research based on secondary data with a qualitative and quantitative approach. Results: 387 files were analyzed with clinical records of patients with cancer between the months of March 2016 to March 2020, whose Elixir was dispensed with medical prescription (34.5%) and pharmaceutical guidance (65.5%).As for the therapeutic response to treatment, these patients reported significant improvement with the complementary use of Pau D'Arco Elixir and did not know of other integrative practices.Diterpene alkaloids extracted from medicinal plants such as Taxol, also have have been used in the treatment of several types of cancer, among others. Conclusion: These results demonstrate the importance of using alternative complementary medicine in the treatment of neoplasms.Este trabalho objetiva avaliar o acompanhamento do uso do Elixir de Pau D’arco (Handroanthus Avellanedae (Lorentz Ex Griseb) Mattos (Sin: Tabebuia Avellanedae Lorentz Ex Griseb) na terapia complementar ao tratamento de neoplasias, produzido e dispensado no Setor de Fitoterapia da Coordenadoria de Políticas de Assistência Farmacêutica da Secretaria de Saúde do Estado do Ceará.Trata-se de uma pesquisa básica, descritiva e documental a partir de dados secundários com abordagem quali-quantitativa, tendo sido analisadas 387 fichas com cadastros clínicos de pacientes portadores de câncer entre os meses de março de 2016 a março de 2020, cujo Elixir era dispensado com prescrição médica (34,5%) e orientação farmacêutica (65,5%). Quanto à resposta terapêutica ao tratamento, estes pacientes referiram melhora significativa com o uso complementar do Elixir de Pau D’Arco e não conheciam outras práticas integrativas. Os alcalóides diterpênicos extraídos de plantas medicinais como o Taxol, também têm sido usados no tratamento de diversos tipos de câncer, entre outros. Os resultados demonstram a importância do uso da medicina complementar alternativa no tratamento de neoplasias

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file