An overview of dentin bonding agents

From the past, there has been a lot of use of the bonding agents in restorative dentistry. Choosing of bonding systems has become a challenge for the clinicians as there was a lot of advances regarding the usage of bonding agents. Each successive modification in the formulae has led to the classification of the bonding system into many “generations”. During the past few years, these bonding agents have been replaced by the same systems that are used on dentin. This change occurred because of the benefit of bonding resin to both enamel and dentin. Extensive research is still on the way to develop the best adhesive system that can produce reliable and permanent bonds to dentin

Resistance to greenbugs in the sorghum nested association mapping population

The greenbug, Schizaphis graminum, is a serious pest of sorghum (Sorghum bicolor). For the past several decades, resistant sorghum hybrids have been used to control greenbug populations. However, the durability of plant resistance is frequently challenged by evolution of new greenbug biotypes, and there is a continuous need for screening of resistant germplasm for its effective management in the field. Natural variation in sorghum plants/populations provides distinct approaches to identify novel sources of resistance against greenbugs. In this study, we used the recently developed sorghum nested association mapping (NAM) population parental lines to understand sources of sorghum resistance to greenbugs. Using choice and no-choice assays, we have identified SC265 and Segaolane as the resistant and susceptible lines, respectively, to greenbugs compared to the wild-type plants. The Electrical Penetration Graph (EPG) analysis revealed that the greenbugs spent significantly lesser time in the xylem and sieve element phases while feeding on the resistant NAM parental line, SC265, compared to the susceptible (Segaolane) and wild-type (RTx430) sorghum lines. In addition, the EPG results indicated that there is no significant difference in the time to first probe, time to reach first sieve element, pathway phase, and non-probing phase among the three sorghum plants, which suggests that the resistance factors present in the vascular tissues of the resistant line (SC265) potentially contribute to the resistance mechanisms against greenbugs. Overall, SC265 NAM parental line showed a combination of antixenotic and antibiotic-mediated resistance mechanisms against greenbugs, whereas the susceptible line Segaolane displayed the least resistance to greenbugs

Physics inspired quantum simulation of resonating valence bond states -- a prototypical template for a spin-liquid ground state

Spin-liquids -- an emergent, exotic collective phase of matter -- have garnered enormous attention in recent years. While experimentally, many prospective candidates have been proposed and realized, theoretically modeling real materials that display such behavior may pose serious challenges due to the inherently high correlation content of emergent phases. Over the last few decades, the second-quantum revolution has been the harbinger of a novel computational paradigm capable of initiating a foundational evolution in computational physics. In this report, we strive to use the power of the latter to study a prototypical model -- a spin-$\frac{1}{2}$-unit cell of a Kagome anti-ferromagnet. Extended lattices of such unit cells are known to possess a magnetically disordered spin-liquid ground state. We employ robust classical numerical techniques like Density-Matrix Renormalization Group (DMRG) to identify the nature of the ground state through a matrix-product state (MPS) formulation. We subsequently use the gained insight to construct an auxillary hamiltonian with reduced measurables and also design an ansatz that is modular and gate efficient. With robust error-mitigation strategies, we are able to demonstrate that the said ansatz is capable of accurately representing the target ground state even on a real IBMQ backend within $1\%$ accuracy in energy. Since the protocol is linearly scaling $O(n)$ in the number of unit cells, gate requirements, and the number of measurements, it is straightforwardly extendable to larger Kagome lattices which can pave the way for efficient construction of spin-liquid ground states on a quantum device

Self-sealing resin fixators in dentistry

Fixed indirect restorations bond to the prepared tooth surfaces with the use of a variety of luting agents depending upon the purpose of that rehabilitation. Success and failures of these restorations have been attributed to the quality of their bond with the tooth substrate. However, the advent of resin-based and self-adhesive resin luting agents have greatly changed this equation by altering the conventional bonding mechanisms and the durability of bond. The limited literature details of these self-adhesive resin luting agents require further exploration for the benefit of dental professionals. This review provides an overview of the composition, chemical interactions, favourable and unfavourable properties to be known for improving the scope of their utilization in dentistry

Corrosion in Titanium dental implants – a review

Titanium (Ti) is the most widely used biomaterial for dental implants as it exhibits excellent mechanical properties and biocompatibility. The biocompatibility of titanium is related to thin, protective surface titanium dioxide (TiO2) layer, which forms a boundary at the implant-biological medium interface, reducing its reactivity with the surrounding biological environment and prevents corrosion. However, the metallic materials used as implants are susceptible to corrosion due to variations in the internal electrolyte environment. The surface oxide layer can be destroyed during insertion of implant or micro-motion between implant and bone under loading conditions. The localized destruction causes corrosion of the implant and induces leak of metallic particles or ions into surrounding tissues. The presence of metallic particles in peri-implant soft and hard tissues may be due to frictional wear or corrosion, or simultaneous occurrence wear and corrosion which is known as tribocorrosion. The released metal ions may remain in the intercellular spaces near the site where they were released or may be taken up by macrophages, or they can migrate systemically. This review article highlights various aspects of corrosion, biological response to corrosion products and prevention of corrosion of titanium dental implants

Solubility of glass ionomer cement in various acidic beverages at different time intervals: an in vitro study

Background: Glass Ionomer is a widely used cement in dentistry for luting and restoration purposes. This cement leaches a large amount of fluoride ions leading to an increase in the early solubility and disintegration in the oral fluids. The solubility of the cement is further aggravated when it is exposed to an acidic medium. Aim: This study aimed to evaluate the solubility of glass ionomer cement (GIC) in various acidic beverages at different time intervals. Materials and Methods: Four commercially available beverages and distilled water was used as immersion media. The pH of the beverages was measured using a digital pH meter. Glass ionomer cement discs were prepared and immersed in beverages for 1 day, 24 hours and 7 days. After completing the immersion time in each beverage for a specific period, the specimens were retrieved and weighed. The solubility was calculated by subtracting the weight at the specific immersion period from the initial weight of the specimen.   Results: Immersion in distilled water demonstrated less solubility compared to immersion in acidic beverages. Among the acidic beverages, GIC immersed in MAAZA showed the maximum solubility compared to the other beverages. One-Way ANOVA displayed a significant difference (p=0.000) among the beverages at different time intervals. Conclusions: This study found that the GIC immersed in fruit juices with preservatives showed more solubility at all time intervals compared to the immersion in carbonated drinks

Surface modifications of dental implants: An overview

Osseointegration is the key for long term success of endosseous dental implants. Implant surface properties like surface roughness, surface topography, surface energy and surface composition are the major characters that influence the process of osseointegration. Several methods have been used to optimise implant surface roughness to increase surface area thereby improving the process of osseointegration. Blasting using alumina and titanium dioxide, acid treatment, anodization, and laser peeling are some of the subtractive methods used to optimize implant surface roughness. Additive methods used to coat HA onto the surface of endosseous implants include plasma sprayed HA, vacuum deposition technique, sol-gel and dip coating method, electrolytic process and nano-HA coating. Recently, biomimetic implant surfaces are produced with calcium phosphate coatings under physiological conditions. These coatings are also capable to act as vehicles for osteogenic agents like BMPs, GDFs and  biologically active drugs like bisphosphonates, gentamicin, tetracycline, etc.,. The methods used for surface modifications of endosseous dental implants are vast and continuously evolving with the recently developed technologies. This article gives an overview on various surface modifications and current trends followed in the field oral implantology

Prosthodontic rehabilitation of a mucormycosis patient: a case report

Maxillofacial defects can result from congenital disabilities, cancer surgery, trauma, infection, or disease. Facial deformities can affect how a person looks, feels about themselves, and interacts with others. It can significantly impair phonetics, mastication, and deglutition and cause facial deformation. Maxillectomy due to mucormycosis is one such maxillofacial defect and it becomes essential to rehabilitate these cases with modified techniques based on the extension of intraoral defect, the severity, the degree of resection, the type of mucormycosis, the stability of lesions over time, the presence of contiguous disease, the accessibility of dental and prosthetic resources, and patient expectations. The prosthetic reconstruction with a maxillofacial prosthesis can restore function and appearance, comfort, and quality of life. The prosthesis should be simple to handle, easy to maintain, biocompatible, light in weight, and convenient for future adjustments. The maxillofacial surgeon, oncologist, and reconstructive dentist should work together to develop a treatment plan based on these considerations. This case report provides the current treatment options for these patients and rehabilitation of the defect. It also discusses the issues that need to be addressed during the planning of prosthetic treatment and highlights some challenges the clinicians face in providing prosthetic treatment for mucormycosis patients

Disinfection of impression materials: A comprehensive review of disinfection methods

Impression making is one of the most common procedures that are performed by dentists in day-to-day practice. These impressions can act as vehicles of transmission and carry various types of microorganisms, which further cause diseases like Hepatitis B, C, HIV, Tuberculosis etc. This contamination and cross contamination of microorganisms can be prevented by disinfecting the impressions immediately after removing from the mouth and label them as disinfected. Usually the impressions are placed under running water to remove saliva and blood, but this will eliminate the disease-causing microorganisms, so a standard protocol to disinfect the impressions and casts should be known to dentists and dental personnel. Various methods of impression disinfection like chemical disinfection, Microwave, Autoclave, Ultraviolet radiation have been described in literature having their own advantages, disadvantages and effects on impression material and casts. Recently antimicrobials and nanoparticles have been incorporated into the impression material itself to make it self- disinfecting. This will not only disinfect the impression material from inside but also disinfect the impressions from the time it is inserted in patient’s mouth.  A broad search on the literature available was performed to provide knowledge about mechanism of action, concentration of usage along with commercial preparations available of different disinfectants. This review article will enhance the knowledge and improve the behavior of dental health care workers about impression disinfection

Resin-bonded fixed partial denture as a cost-effective prosthesis for missing maxillary lateral incisor in a cleft lip and palate patient: a case report

Literature suggests 66.7% of dental abnormalities among patients with cleft lip and palate (CLP). Besides posing functional difficulties, dental anomalies also raise significant aesthetic concerns among these patients, especially with missing teeth in the anterior region. Among various treatment choices like a removable partial denture, fixed and implant treatments available in the prosthetic rehabilitation of missing teeth in CLP subjects, Maryland bridges offer a conservative and cost-effective alternative in short-span edentulous spaces while carrying the advantages of supragingival marginal preparations and less intensive working times. The availability of advanced self-etch adhesive systems that chemically bond to both the tooth and metal surfaces offer these prostheses more longevity. This case report presents the fabrication of a resin-bonded fixed partial denture in the prosthetic rehabilitation of a missing maxillary lateral incisor in a 23-year-old female patient with CLP who was unwilling for orthodontic care