Denture Adhesives in Prosthodontics- An Overview

Denture Adhesives in Prosthodontics- An Overview Dr Ranjith Kumar P, MDS; Dr Shajahan PA,MDS ; Dr Jyothis Mathew, MDS ABSTRACT Denture adhesives are used by an endless number of denture wearers and also by the dentists who fabricate them. Prescribing denture adhesives has been viewed by many prosthodontists as a means of compensating for deficiencies in clinical and technical procedures. Denture adhesives increase retention and thereby improve chewing ability, reduce wobble, improve comfort and confidence and reduce amount of food particles collecting under the dentures. Moreover, they undoubtedly provide the patients an increased sense of security and satisfaction. However, patients should use denture adhesives only on the advice of their dentists. INTRODUCTION Though their usage dates back to the late 18th century, they were first mentioned in dental literature in the 19th century. Earlier adhesives, formulated by mixing vegetable gums absorbed moisture from the saliva and swelled to a mucilaginous substrate that adhered to the mucosa of the mouth and the denture. Kapur’s 1 study in 1967 on 26 denture wearers, concluded that denture adhesives increased denture retention, thereby improving denture wearers’ incisive ability. Stafford and Russell, 2 using radio telemetry, measured the change in pressure, at the denture base-mucosa interface, with and without adhesives and found that denture adhesives allowed greater total occlusal pressure. The denture adhesives improved denture retention and stability (Tarbet et al 3), and found that patients perceived improved chewing ability, confidence and comfort, reduced wobble and collection of food particles under denture. Chew et al 4 determined the effectiveness of denture adhesive in improving the retention and stability of the complete maxillary denture in vivo using Kinseography. Abdelmelak and Michael 5 suggested that the denture adhesives acts as a cushion under complete denture; reducing the transmission of pressure and friction to the underlying mucosa. COMPOSITION The major constituents of denture adhesives can be broadly divided into three groups.6 Group 1 (Adhesive agents): Tragacanth, acacia, pectin, gelatin, methyl-cellulose, hydroxyl-methyl cellulose, Karaya Gum, sodium carboxyl-methyl cellulose and synthetic polymers (polyethylene oxide, acrylamides, acetic and polyvinyl). Group 2 (Anti-microbial agents) Sodium borate, sodium tetraborate, hexachlorophene and ethanol. Group 3 (Other agents) Plasticizers, wetting agents and flavouring agents such as oil of wintergreen, oil of peppermint, etc. Mechanism of Action Denture adhesives are supplied as paste, powder or cream. As the Adhesive powders absorb water, they swell to many times their original volume and the resulting anions are attracted to cations in the mucous membrane proteins. Sticky saliva thus formed increases the viscosity of the adhesive, thereby increasing the denture retention.7 Newer adhesive materials provide stronger bio-adhesive and cohesive forces. Free carboxyl groups formed by the hydration of adhesive such as methyl cellulose, hydroxyl methyl cellulose, sodium carboxyl-methyl cellulose or poly methyl vinyl-ether maleic anhydride (PVM-MA), etc. form electrovalent bonds that produce stickiness or bio adhesion. The increased viscosity of the adhesive creams result in their lateral spread excluding air and saliva thereby increasing the retention 8. Requirements of an ideal Denture Adhesive 9 Available as gels, creams and powders. Nontoxic, non-irritant, and biocompatible with the oral mucosa. It should have a neutral odour and taste. Easy application and removal from the tissue surface of the denture. Discourage microbial growth. Adhesiveness should be retained for 12-16 hrs. Increase the comfort, retention and stability of the denture Mode of application: Any residual adhesive should be removed from the tissue-bearing surface of the denture . The denture bearing tissues are wiped clean of any food debris. Wet dentures before application of adhesive. Small amounts of adhesive is applied to the tissue-bearing surface of denture. In the maxillary denture -Anterior alveolar ridge, the center of hard palate and posterior palatal seal region . In the mandibular denture apply to the sulcus of denture over the crest of the ridge extending from the anterior region sulcus to the distal extension. Denture should be seated and held in place firmly by hand pressure for 5-10 seconds. Gauze is used to remove excess adhesive . Patient is advised to close into centric occlusion several times to spread the adhesive as a thin even layer. Indications. Recording jaw relations and denture try in should be done using stable and retentive bases. The use of denture adhesive can stabilize the trail denture bases which show inadequate retention and stability due to various reasons. Use of adhesive will improve the accuracy of the denture try-in, and also decrease the patient apprehension about the fit of the final prosthesis. Use of adhesives in patients with compromised denture bearing areas adds to their confidence thereby increasing the ability to adapt to the new prosthesis. Immediate denture get loosened soon due to soft tissue healing and bony resorption requiring relining, rebasing, or a new denture fabrication. A soft liner used to augment the retention; comfort and function during the interim period are aided by the use of a denture adhesive. Reduced clinical findings of ulcers, tissue irritation, compression, and inflammation of the oral mucosa of denture wearers were seen with concomitant use of adhesives. Xerostomia in denture wearers either drug or radiotherapy induced can be alleviated with the use of denture adhesives. Stabilization of dentures in patients with hormonal changes and neuromuscular disorders such as myasthenia gravis, Parkinson’s and Alzheimer’s disease, etc., can be achieved with denture adhesives. Prosthesis to rehabilitate gross maxillofacial defects requires denture adhesives for retention. Denture adhesives are valuable adjuncts to the retention of radiation carriers or radiation protection prostheses. Usage of minimal amounts of adhesives provides high profile patients like attorneys, executives, speakers, etc. with psychological security in social situations. Contraindications Allergies to denture adhesives or any of its components. Gross inadequacies in retention and function. Excessive bone resorption and soft tissue shrinkage leading to loss of vertical dimension. Adhesives should not be used to retain fractured dentures or dentures with missing flange or with sectional fractures. Patients with inability to maintain proper hygiene of the denture should avoid use of denture adhesive. Conclusions Denture adhesives, when used properly are safe and beneficial to the patient in increasing retention and stability, enhanced comfort, improved function, and in providing psychological satisfaction. They should not be used as an aid to compensate for denture deficiencies even though adhesives enhance denture performance. Patients should not use denture adhesives inadvertently without proper guidance and instructions from the dentists.

Lvmh Case Study

The key question in this case is can LVMH continue to successfully manages of its different brands while making sure they are all profitable. I like the focus that the company puts on its â€Å"star brands†. Focusing on the brands that continue to grow and bring in profits will help the company stay profitable. While focusing on the star brands is a good strategy it is far from all that LVMH needs to do to be a successful conglomerate. It appears that in the fashion world human resources are the most valuable asset that a company can have, and LVMH needs to do a much better job treasuring these assets.The conglomerate damages its image and its profitability by mistreating its creative talent. The conglomerate’s image is damaged because key creative personnel, which in a sense are the face of the different brands, leave and publicize why they left which tarnishes the conglomerate’s image thus making it harder to attract the best talent in the market. The conglomer ate’s profitability is jeopardized because they lose the designers that make the products that make the companies profitable.LVMH could strengthen their relationships with the smaller companies by creating incentive programs that not only compensate based on volume of sales but incentive programs that compensate based on sales growth and maintained profitability. With this new incentive program the company would have more opportunity to recognize the Michael Kors of the company. LVMH should focus more on economies of scope. In some cases like advertising it appears the conglomerate uses its size and power to reduce the cost to the individual companies; however I feel that the conglomerate could do much more to reduce costs and increase profits for the firms.They could be using their negotiating power to force suppliers into lower prices. They should encourage the individual companies to work together and provide ideas for each other this way they can strengthen relationships among the companies and create a more unified feel for the conglomerate. Finally LVMH should make sure that they are avoiding managerialism. They need to make sure the companies that are acquired are actually valuable to the conglomerate as a whole and that they are not cannibalizing profits from one or more of the current companies.

Limiting Reagents Lab Essay

Problem: What mass of precipitate will form when 1.69g of CuCl2.2H20 reacts with 1.31g of aluminium? Aspect 3: Materials: > 150 mL beaker > Erlenmeyer Flask > 100ml Graduated Cylinder > Funnel; > Scoopula > Electronic Balance > Stir Rod > Aluminum Foil > CuCl2.2H20 > Distilled Water Procedure: Day 1 > Rinse beakerwith distilled water. > Mass 1.69g of CuCl2.2H2O. > Add to beaker and add 50mL of distilled water. > Mass aluminum. Fold in 1/2 & coil loosely. > Place in beaker and let sit overnight. Day 2 > Pull out Aluminum and rinse into beaker > Mass filter paper, put name on it > Put paper in funnel and funnel into the Erlenmeyer flas. > Pour in mixture. Rinse beaker three times. > Rinse funnel and paper twice. > Remove Paper and let dry overnight. Day 3 > Mass filter paper Data Collection and Processing (DCP) Aspect 1: Recording Raw Data: Mass of CuCl2.2H2O – 1.93g Mass of Al – ? (The massing of the aluminum was forgotten) Experimental mass of precipitate = .69g Aspect 2: Processing Data 2Al(s) + 3CuCl2.2H2O –> 3Cu(s) + 6H2O(l) + 2AlCl3(aq) m Al=1.93g M Al= 26.98 g/mol m 3CuCl2.2H2o = 1.69 g M 3CuCl2.2H2o = 152.47 g/mol (Chem 20 Data Booklet) m Cu = ? n CuCl2.2H2O = 1.93g / 170.49 g/mol n CuCl2.2H2O = .011320312 mol 3 mol CuCl2.2H2O = 3 mols Cu n Cu = .011320312 mol m Cu = .011320312 mol x 63.55 g/mol m Cu = .719g % yield = .69 / .719 = 96% Aspect 3: Experimental mass of Cu(s) precipitate = .69g Theoretical mass of Cu (s) precipitate = .719g % yield = 96% Conclusion and Evaluation (CE) Aspect 1: Conclusion: The mass of precipitate that forms when 1.93g of CuCl2.2H20 reacts with 1.31g of aluminum is .69 g. The % yield was 96%. The massing of aluminum was forgotten but when another piece was massed and the numbers were worked out, it was shown that there was an excess of aluminum and that the CuCl2.2H2O was the limiting reagent. Aspect 2: Evaluate: There were .029g of Cu precipitate less than expected. It is likely that some of the copper went into the Erlenmeyer or was stuck on the funnel. Despite thorough rinsing of the filter paper, some of the precipitate got through the filter paper and into the Erlenmeyer. Aspect 3 Improving Experimental Design: Instead of one piece of filter paper, two pieces should be used. This would lead to less precipitate going into the Erlenmeyer. Also, the water in the Erlenmeyer could be re-filtered.

Definition and Examples of Text in Language Studies

In linguistics, the term text refers to: The original words of something written, printed, or spoken, in contrast to a summary or paraphrase.A coherent stretch of language that may be regarded as an object of critical analysis. Text linguistics refers to a form of discourse analysis—a method of studying written or spoken language—that is concerned with the description and analysis of extended texts (those beyond the level of the single sentence). A text can be any example of written or spoken language, from something as complex as a book or legal document to something as simple as the body of an email or the words on the back of a cereal box. In the humanities, different fields of study concern themselves with different forms of texts. Literary theorists, for example, focus primarily on literary texts—novels, essays, stories, and poems. Legal scholars focus on legal texts such as laws, contracts, decrees, and regulations. Cultural theorists work with a wide variety of texts, including those that may not typically be the subject of studies, such as advertisements, signage, instruction manuals, and other ephemera. Text Definition Traditionally, a text is understood to be a piece of written or spoken material in its primary form (as opposed to a paraphrase or summary). A text is any stretch of language that can be understood in context. It may be as simple as 1-2 words (such as a stop sign) or as complex as a novel. Any sequence of sentences that belong together can be considered a text. Text refers to content rather than form; for example, if you were talking about the text of Don Quixote, you would be referring to the words in the book, not the physical book itself. Information related to a text, and often printed alongside it—such as an authors name, the publisher, the date of publication, etc.—is known as paratext. The idea of what constitutes a text has evolved over time. In recent years, the dynamics of technology—especially social media—have expanded the notion of the text to include symbols such as emoticons and emojis. A sociologist studying teenage communication, for example, might refer to texts that combine traditional language and graphic symbols. Texts and New Technologies The concept of the text is not a stable one. It is always changing as the technologies for publishing and disseminating texts evolve. In the past, texts were usually presented as printed matter in bound volumes such as pamphlets or books. Today, however, people are more likely to encounter texts in digital space, where the materials are becoming more fluid, according to linguists David Barton and Carmen Lee: Texts can no longer be thought of as relatively fixed and stable. They are more fluid with the changing affordances of new media. In addition, they are becoming increasingly multimodal and interactive. Links between texts are complex online, and intertextuality is common in online texts as people draw upon and play with other texts available on the web. An example of such intertextuality can be found in any popular news story. An article in The New York Times, for example, may contain embedded tweets from Twitter, links to outside articles, or links to primary sources such as press releases or other documents. With a text such as this, it is sometimes difficult to describe what exactly is part of the text and what is not. An embedded tweet, for instance, may be essential to understanding the text around it—and therefore part of the text itself—but it is also its own independent text. On social media sites such as Facebook and Twitter, as well as blogs and Wikipedia, it is common to find such relationships between texts. Text Linguistics Text linguistics is a field of study where texts are treated as communication systems. The analysis deals with stretches of language beyond the single sentence and focuses particularly on context, i.e. information that goes along with what is said and written. Context includes such things as the social relationship between two speakers or correspondents, the place where communication occurs, and non-verbal information such as body language. Linguists use this contextual information to describe the socio-cultural environment in which a text exists. Sources Barton, David, and Carmen Lee. Language Online: Investigating Digital Texts and Practices. Routledge, 2013.Carter, Ronald, and Michael McCarthy. Cambridge Grammar of English. Cambridge University Press, 2006.Ching, Marvin K. L., et al. Linguistic Perspectives on Literature. Routledge, 2015.