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– Often, polysulfide materials are called “rubber” or “rubber base” materials, even though polyether and silicone materials are also rubber materials. All impression materials that were poured immediately and evaluated using a custom tray and adhesive consistently demonstrated superior results in comparison to those tested without the custom tray. (Agar). ¾It can be achieved by vulcanization - an irreversible chemical reaction usually at high temperatures, and usually involving the addition of sulphur compounds. Irreversible. The focus is on primary impression, spacer design , secondary impression and the choice of impression materials. Hold ™ Tray Adhesive provides that extra confidence. Elastomeric materials were intended for impressions for inlays, crowns, and FPDs. elastomeric Impression DENTAL material 1. Insurance data show drop in opioid prescriptions by dentists June 25, 2019 -- An insurance company studied internal data and found that general dentists reduced the number of days of supplied opioids prescribed by 9% over a three-year period, according to research presented at the 2019 International Association for Dental Research meeting. Impression materials 1. Aim: The study aim was to assess present practice concerning impression techniques and materials used for making complete denture in Saudi Arabia. Quazi, Krishnakumar S. – Other impression materials set by a physical change when they cool, either by solidification or by gelation. Traditional vs. Impression Techniques and Materials for Complete Denture Construction. Of the rigid types, impression plaster was the first material used for both edentulous and dentulous impressions. Single-use, plastic impression trays provide a disposable alternative to heat sterilization. Conclusion This article describes fabrication The initial setup includes choosing the correct impression material (whether alginate or polyvinyl), setting up the mixing pads, spatulas, adhesive, lubricating agents, mixing bowls, and a whole slew of different tray size options. Our new CrystalGraphics Chart and Diagram Slides for PowerPoint is a collection of over 1000 impressively designed data-driven chart and editable diagram s guaranteed to impress any audience. What is the triple tray technique, why is it gaining popularity. com/Dental-Material-Lectures-by-Dr-Rash PDF | Dental impression making is the process of creating a negative form of the teeth and oral tissues, into which gypsum or other die materials can be processed to create working analogues. Find PowerPoint Presentations and Slides using the power of XPowerPoint. Some of the older impression materials (eg, zinc oxide eugenol impression paste, impression plaster, and impression compound) are still used in certain applications but are limited in use because they cannot be removed past undercuts without distorting or fracturing the impression . Base paste-Low  There are four main types of impression material that are routinely used in dentistry. and various online dental courses having best faculty of world wide repute An ideal impression material should also have good elastic recovery when it is used in undercut situations and should have good tear resistance. Regarding alginate impression material: a. In the wax beading and boxing technique, casts may be lopsided (high on one side & low on the other side) because of the difficulty of proper orientation of the impression prior to boxing, while in hybrid technique, this kind of problem is prevented by What is Elastomeric Impression Materials? Definition of Elastomeric Impression Materials: Silicone or polyether materials used to obtain an accurate replica of the hard and soft tissue for the fabrication of patient diagnostic and working casts. While conventional elastomeric impression materials are still being used to generate excellent impressions, the future of impression-taking is undoubtedly with digital intraoral scanners. 2 There are a Representative linear contraction of four elastomeric impression materials www. This is affected by use A dental impression is a negative imprint of hard (teeth) and soft tissues in the mouth from which a positive reproduction (cast or model) can be formed. The impression material used is usually an elastomeric impression material; the two types most widely used and shown to be the most appropriate are polyether and polyvinyl siloxane impression BASIC SCIENCES AND APPLIED PHYSICS 1BASIC SCIENCES. This can be more critical when using all-ceramic materials, as they require minimum thicknesses to perform as expected. This is in accordance with Curso M 4 who stated that cooling of the elastomeric impression from mouth temperature to room temperature has been correlated with a decrease in dimensional accuracy because of a high coefficient of thermal contraction of elastomeric impression materials. recent advances. The limit of reproduction is also lower, indicating that less fine detail will be obtained. So, to overcome all these problems, campagna impression technique was employed due to its greater potential for more accurate impression of the labial vestibules. The elastomeric impression materials available are silicones (addition and condensation cured) and polyethers. Consistent with dental infection-control guidelines for semicritical instruments, chrome-plated and aluminum impression trays can be cleaned, packaged, and heat-sterilized. Meanwhile, the dimensions of the impression should remain stable during the production of dies or casts. com - id: 70f57a-OTViM REVIEW OF DENTAL IMPRESSION MATERIALS R. Abstract. LOW copper amalgam alloy b. The selective impression technique is recommended for removable prosthodontics. Additionally, impression materials should also have optimal elastic recovery properties. – Impression materials set by che mical reactions to form elastic rubber materials are called thermoset. At least 43 different brands of polyvinyl siloxane impression materials are offered by at least 29 different companies. they can be easily streched and easily recovered their original dimension when applied stress is realesed. ZOE paste. Creep value of all the above mentioned alloys is same e. 1. Polyether. pptx (Size: 6. In the history of operative dentistry, direct restorative materials have principally included: lead, mastic, gold, tin, amalgam, fusible metal of Darcet, gutta percha, silicate cement, directfilling methyl methacrylate resin, composite resin and glass ionomer cement. Elastomeric Materials (temporary cement) Used when an accurate impression is essential. Learn vocabulary, terms, and more with flashcards, games, and other study tools. 1955 Pearson reported on the polysulfide base materials. High copper amalgam alloy. 2. However, since it is rigid on setting, it must be carefully fractured (at the cupids and A dental impression is a negative imprint of hard (teeth) and soft tissues in the mouth from which a positive reproduction (cast or model) can be formed. [4]Impression materials disinfected by immersion, however may be subjected to dimensional changes which may have a direct effect on the prosthetic results achieved in dental practices. [Article in Hebrew]. However, the viscoelastic rheological properties of impression materials, particularly the time-dependent viscoelastic changes in impression material immediately after tray seating, are unknown. single composition alloys d. To simplify the selection process, clinicians should look for a smooth-flowing, hydrophilic material that has good tear strength, shrinks very little upon setting, and can be poured Elastic impression materials. SCIENCE OF DENTAL MATERIALS MODEL PAPER (MCQs) 38. Elastomeric impression materials (addition silicones and polyethers) offer high elastic recovery and Download Presentation Elastomeric Impression Materials An Image/Link below is provided (as is) to download presentation. • 1950s elastomeric impression materials introduced: polysulfide, silicone base • 1955 Pearson reported on the polysulfide base materials. Thus a greater force is needed to remove a impression tray from undercuts in mouth. Clinicians Reaping Benefits of New Concepts In Impressioning. Rubber-like qualities, self-curing and supplied as a base and catalyst (accelerator). 36 MB / Downloads: 71) INTRODUCTION The goal of dentistry is to maintain or improve the quality of life of dental patients and this requires the replacement or alteration of tooth structure and selection of biocompatible, long lasting , prosthetic material that can withstand most of the conditions in oral cavity. Elastic Impression Materials and Denture Adhesives – A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow. The object of making an impression in implant dentistry is to accurately relate an analogue of the implant or implant abutment to the other structures in the dental arch. Impression Materials PPT - Download as Powerpoint Presentation (. 1 The use of custom fabricated trays with elastomeric impression materials can improve the accuracy of the working model. Elastomeric impression materials (polyethers, polyvinyl siloxanes, and hybrids) are popular because of their excellent physical and mechanical properties, including precise detail reproduction, high elastic recovery, and dimensional The results clearly show that only alginate is being used by a large percentage in the nonmetro areas in spite of the proven fact that elastomeric impression materials are better than alginate for impression making, the reason being the cost which is higher for elastomeric impression materials. Polymers have a major role in most areas of restorative dentistry. The first high accuracy impression material, elastomeric impression material, was used for dental purposes in the 1950s (1, 7). Clinically relevant mechanical properties of elastomeric impression materials. Oct 13, 2016 Among the broad range of elastomeric impression materials, the vinyl for each impression technique (Table 2). com Slide 17: For visco-elastic material slow elastic recovery may control for sometime after withdrawal of the impression, producing dimensional change. Designed for outstanding flow over a long working time, 3M™ Impregum™ Polyether Impression Materials deliver precise, void-free impressions even The philosophy behind making the final impression with custom trays is to provide a well-fitting impression tray that is comfortable for the patient, contains an adequate amount of impression material to obtain an impression that reproduces fine details, minimizes waste of expensive impression materials, and assures proper intraoral seating of Advantages of elastomeric impression materials over the hydrocolloid Elastomeric impression materials have higher tear strength than hydrocolloid. till the impression becomes elastic enough to resist deformation during its withdrawal from the mouth Impression com-pounds ZnO-eugenol (ZOE) Impression plaster Inelastic/rigid Alginate Agar hydrocolloid Elastomeric: Polysulfide Polyether Silicone Elastic Irreversible Reversible Classification of impression materials Elastomeric Impression materials: These are basically synthetic rubber based materials which were initially called as Rubber Impression materials but currently they are known as Non aqueous Elastomeric Impression materials. Putty-Wash Techniques for Polyvinyl Siloxane Impres sions: A Review Mohsin A. A polyether material have greater stiffness than all other elastomeric impression materials. Purpose. Elastomeric impression materials (addition silicones and polyethers) offer high elastic recovery  Elastomeric Impression Materials Polysulfide Polyether Polyvinylsiloxane (known as addition silicone) All are supplied as 2-paste systems (tubes): Base +  Refuat Hapeh Vehashinayim (1993). txt) or view presentation slides online. Impression Use 2-step techniques: Impression Tray (a) Light-Heavy Body, OR (b Precleaning removes additional bioburden and any adherent impression materials. If the metal flexes, the porcelain veneer on it might crack or separate. Burgess, DDS, MS, Guest Editors. Although new elastomeric impression materials have been introduced into the market, there are still insufficient data about their mechanical features. indiandentalacademy. G. Except for the polyethers, all other elastomeric impression materials are hydrophobic. Light body elastomeric impression materials is placed on the area covering the window portion and then while the first tray is still in the mouth the pickup tray is positioned over it and border moulding movements are repeated (Fig 6,7). ELASTOMERIC IMPRESSION MATERIALS BY Dr Rashid Hassan for more lectures on Dental materials visit https://www. Materials and Methods: This study was conducted between December 2013 and February 2014 through self-administered survey. Another major type of polymeric dental material is the composite filling material for anterior teeth. Impression; Techniques; Materials; Complete; Denture; Dental; Saudi Arabia . Chart and Diagram Slides for PowerPoint - Beautifully designed chart and diagram s for PowerPoint with visually stunning graphics and animation effects. CRAIG Department of Biomaterials, School of Dentistry, University of Michigan, Ann Arbor, Michigan 48109 Adv Dent Res 2(l):51-64, August, 1988 ABSTRACT Major advances in impression materials and their application have occurred during the last decade, Blog. How to present a project and impress your audience: Top 6 tips; 27 June 2019. 1). The accuracy of these final restorations is highly dependent on the impression materials and techniques utilized. Newer elastomeric materials for combination impression technique with double custom impression trays4,5 but it leads to over-extended labial flange. William H. First, in the sol (solution) phase, the material is in a liquid or semi-liquid form. >Second, in the gel (solid) phase, the material is semisolid, similar to a pudding dessert. Such a material would possess a comparative high modulus of elasticity. area. Polyether Impression Materials 3M polyether dental impression materials and tools give you the control you need for multi-unit restorations, implant impressions and other challenging indications. Many dentists are reluctant to embrace the new technologies because they simply believe elastomeric impression materials and techniques have been in use for so long and work so well that they are irreplaceable. The compressive and tear strengths increase with increasing rates of deformation. surface of elastomeric impression is difficult. Our traditional dental impression materials, tools and kits can help you efficiently create accurate dental impressions for a variety of applications, including crowns, bridges, inlays, overlays and implants. Jun 4, 2014 elastomeric Impression DENTAL material. Most of elastomers can be electroplated. What is Elastomeric Impression Materials? Definition of Elastomeric Impression Materials: Silicone or polyether materials used to obtain an accurate replica of the hard and soft tissue for the fabrication of patient diagnostic and working casts. Taggart demonstrates the method for use in dentistry in 1907. Not recommended for use with elastomeric impression materials. Please enter a Patterson Item Number in the correct format. Lahoti, Jaykumar R. The primary impression in this technique makes use of low MSE 2090: Introduction to Materials Science Chapter 15, Processing of Polymers 26 Elastomers: Vulcanization (I) ¾Croslinking is one of the requirements for elastomeric behavior. Theories of impression making have evolved trough trial of a variety of materials and techniques. Digital Impression Techniques Accurate impressions depend on proper technique and materials. In prosthodontics, impression materials are used to record intraoral structures for the fabrication of definitive restorations. Tear strength Elastomeric impression materials are viscoelastic, and their mechanical properties are time dependent. introduction elastomer refers to the group of ruberry polymers, which are either chemically physically cross linked. – Often, polysulfide  of an alginate impression is not acceptable, As such elastomers were developed to capture  Elastomeric: Polysulfide. Regular Permlastic is recommended for partial- or full denture impressions because it has a high degree of flow that will register the finest detail. It is made by placing an appropriate material in a stock or custom dental impression tray which is designed to roughly fit over the dental arches. Egypt Dent J 41: 1409-1416, 1995 Hung SH, Purk JH, Tira DE, Eick JD: Accuracy of one-step versus two-step techniques with use of putty/wash addition silicone impression materials. Wax Non Elastomeric. Peer-reviewed articles, published in English and in French between 1954 and 2007, were identified through a MEDLINE search (Pubmed and Elsevier) and a hand search of relevant textbooks and annual publications elastomeric impression materials. A dimensionally accurate impression is one of the primary determinants for a precise fitting indirect restoration. The most commonly used impression technique, as seen in our dental laboratories, is the all-in-one, which utilizes a full- or dual-arch impression tray with a combination of heavy-body tray material and a flowable wash (Fig. First practical research with the material in complete denture construction. i ; 3* 3 Q». The clinical success of the indirect restoration requires a precise working model and thus depends upon the accuracy of the final impression. SHRINKAGE MANAGEMENT Elastomeric impressions. Classification of impression materials. Exceeding working time . am) L13, was: £16,447 . Aim: Dental impressions often carry microorganisms that may cause cross infection from patients to dental staff. How to use Prezi Analytics to learn from your presentations Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats and courses we offer Dental Implantology, fixed orthodontics, rotary endodontics,General dentistry. When we classify dental restorative materials we see three major groups. Updated on: July 10, 2017 A. Confusion abounds and is further complicated by the omission from marketing literature of some information about PVS materials that is instrumental in using them and understanding how to get the best results from them. Feb 19, 2015 Contents Introduction History Elastomers Polysulphide rubber impression material Composition Setting reaction Properties of  dependent on the impression materials and techniques utilized. Aug 2, 2016 Polysulfide impression material was the first non aqueous elastomeric “rubber” impression material developed for dentistry. This in-vivo study evaluated microbial load on impressions (dentulous and edentulous) and the effectiveness of various disinfectants on the reduction of microorganisms from the impression surfaces after immersion and spray disinfection of impressions using five Materials with high tensile strength will display less of such side effects. >Hydrocolloid impression materials have two physical phases. Polyether material consistently yielded superior results with or without a custom tray when compared to the other impression materials. Polymer (high shrinkage) Filled Polymer (low shrinkage) Impression During setting shrinkage, distortion of impression is toward tray. Modern materials are robust, precise, fast, hydrophilic, and can be automatically mixed – but still the patient needs to keep a filled impression tray in the mouth for some very long minutes, The condensation silicone impression materials are supplied as a base paste and a low-viscosity liquid or catalyst paste. Juniordentist. 2011 Apr;28(2):54-64, 75. The gel strength of hydrocolloid is not as great as that of elastomeric impression materials. The tensile properties of 17 hydrophilic impression materials with different consistencies were compared. elastomeric impression materials to their surface: metal standard impression tray for the upper jaw framed with an adhesive tape (1), application of adhesives on the trays (2) Standard impression trays are available in sets and come in different sizes. Creep value of w hich of the following is highest? a. Impressions can be used to create mouth guards, whitening trays, retainers, crowns, bridges, veneers, dentures, and accurate models, among other things. Unless otherwise noted, the content of this course material is licensed under a Creative For Elastic Impression Materials ELASTOMERIC IMPRESSIONS. IRREVERSIBLE HYDROCOLLOIDS (ALGINATE) Alginate impression materials are used for full-arch impressions because of their low cost and good wetting properties,2 making them a popular choice to fabricate diag-nostic casts. Admix alloy c. Or else, that 3D digital scanning technologies are so recent that they are not yet ready for clinical use. Elastomeric = Rubber-like polymers that show an elastic  Sep 15, 2017 different types of elastomers. com, find free presentations research about Agar Impression Material PPT It will be weak and filled with air spaces Summary of Module Key Terms Elastomeric impression materials Gypsum materials Laboratory Materials and Techniques: Diagnostic Casts Part A: Elastomeric Impression Materials Part B: Gypsum Materials Polysulfide Polyether Polysiloxane Polyvinal siloxane Two-Part Pastes Putty Extruding Gun Accelerator tissues under a mucostatic impression act as a confined liquid. If you have ever had serious dental work done, it is likely that you had had a dental impression taken dental impressions are very common and are used for a variety of purposes in the dental field. mary of the properties of elastomeric impression materials is shown in (Table 1). Despite perforations in metal or plastic impression trays to help retain alginates, many practitioners prefer a stronger adhesive bonding between alginate and tray. Silicone-based impression materials are elastomeric impression materials used View and Download PowerPoint Presentations on Agar Impression Material PPT. These materials are often used as an interocclusal registration material. applications. Recently, manufacturers have marketed alginate impression materials, in that it governs elastomeric impression materials and specifies that the dimensional  ELASTOMERIC IMPRESSION MATERIALS: Polysulfide Rubber Impression Material: Polysulfide rubber impression material consists of. 9. Key: a 39. (C) Institute of Medical Biochemistry, 1st Fac. Elastic. They can be categorised into either rigid impression materials (zinc oxide  Failure of the impression material to adapt to the teeth. Amongst the elastomeric impression technique, Over the years, a lot of materials and impression techniques were developed to achieve perfect detail reproduction of the oral environment. View Dental Materials Review from LEVEL II Dental Ass at Everest College. Elastomers. However, the elastomeric impression materials we refer to in dentistry can very well be described as "condensation" polymerized impression materials, because the release by-products which cause shrinkage of these materials over time after setting. Silicone. Elastomeric Impression Materials 2. Because elastomeric impression materials have so many physical and mechanical components, selecting the proper one for a given application can be quite tedious. Pekkton® ivory - Step-by-Step (Press method) with anaxFORM LC Kit and Creopal Shell (EN) - Duration: 11:13. Gade Department of Prosthodontics, Swargiya Dadasaheb Kalmegh Smruti Dental College & Compromised ridges, abused tissues, impression techniques Krishna Prasad D. Even if selective pressure is the most accepted and followed impression philosophy; there are variations in designing of the custom tray for the same, as advocated by different academicians [3-14]. Crown and bridge impressions can either be described as an all-in-one impression or a two-step impression technique. It is not intended to replace your Dental Visit. It has higher permanent deformation upon stretching to pass over undercuts. System makes the impression-taking process, including all preparatory and subsequent work, easier and more convenient. Permlastic is a polysulfide, condensation-cured, elastomeric impression material in three viscosities. methods of manipulation. Use of a wash impression is difficult in a completed inlay/onlay impression, as complete seating can be complicated and lead to either a “stepped” or distorted impression. Classification of Elastomeric Impression materials: Till now the elastomeric impression materials are divided into 3 types This article reviews the current trends in materials used for complete denture impression. ppt), PDF File (. Start studying Dental Materials Ch 21 Disinfection of Impressions & Ch 30 Elastomeric Impressions. Start studying Chapter 46 - impression materials. Plaster. Download: PPT. Literature review endorsed using existing elastomeric impression materials such  . These are metals, ceramics and polymers. Aqueous. Dies tend to be oversize and so the casting is oversize. e U . Levartovsky S(1), Folkman M, Alter E, Pilo  Elastomeric Impression materials: These are basically synthetic rubber based materials which were initially called as Rubber Impression materials but currently . The patient’s mouth is a challenging environment in which to make an accurate impression, the moisture control is probably one of the most important aspects of successful impression making. Examples are: 123-1234, 123 1234, 1231234, 071231234, 07-123-1234 Depending on the distribution and degree of the chemical bonds of the polymers, elastomeric materials can have properties or characteristics similar to thermosets or thermoplastics, so elastomeric materials can be classified into: Thermoset Elastomers - are those elastomer materials which do not melt when heated. 1973 First moldable acrylic material. 1950s elastomeric impression materials introduced: polysulfide, silicone base. Jun 18, 2007 Impression materials. Habib AN, Shehata MT: The effect on the type and technique used for impression making on the accuracy of elastomeric impression materials. This standard is for elastomeric dental impression materials based, for example, on polysulfides, polysiloxanes, polyethers, or other non-aqueous materials capable to reacting to form a rubber-like material which can be used for taking impressions. A dental impression is defined as the negative record of thetissues of the mouth . Use of Gypsum Products in Dentistry – Gypsum products are supplied as fine powders that are mixed with water to form a fluid mass that can be poured and shaped and that subsequently hardens into a rigid, stable mass. The impression technique takes into consideration the varying histological characteristics of the soft and hard tissues in the mandible. He also reported that storage of impressions at a temperature elastomeric impression materials in terms of accuracy and dimensional stability, with respect to obtaining multiple casts from a single elastomeric impression at various times of pours. Nathaniel C. The more di- The Lost Wax Technique: From Impression to Restoration Centuries old technology used in jewelry making, art, and many other applications. The synthetic elastomeric materials in general meet these high demands. Then, we have to select the correct maxillary and mandibular tray, prep the tray, and start mixing the materials. All types of elastomeric impression materials undergo Properties of Elastomeric Impression Materials. It is used to reproduce the form of theteeth and surrounding tissues. thumbnail. Compound. Updated on: July 11, 2017Polysulfide impression material – Polysulfide impression material was the first non aqueous elastomeric “rubber” impression material developed for dentistry. Only a proper dental Checkup by a professional in person can help diagnose the problem you are suffering from and help give you the required treatment. Elastic recovery is the ability of the alginate material to recover its shape after it has been deformed during removal from the mouth. com is intended for educational, informative and entertainment purposes only. Elastomers have no synersis or imbibition like hydrocolloids. 3 July 2019. Elastomeric = Rubber-like polymers that show an elastic behavior at the time of load application These polymer molecules have weak interaction in between (Van der Wall forces), although they are tied together in 3D network. The goal of impression making is to produce an accurate impression that can yield a cast or die that reproduces the surface details and precise shape of the original tissue as closely as possible. facebook. – The chemical reaction invo lves chain lengthening, cross-linking, or both. For example, the higher the rate of deformation, the higher the tear strength From greatest to least polysulfide > addition silicone > polyether > condensation silicone . pdf), Text File (. Materials and methods: Three master dies were prepared for the impression making, two of these were made of brass containing a central hole with undercuts. [1] TYPES OF IMPRESSION MATERIALS: Major advances in impression materials and their application have occurred during the last decade, with Dental impressioning materials from 3M are designed for less mess, less stress and more control at every step. Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Reversible hydrocolloid. Beeswax represents the first impression material, while important bechmarks during the historical evolution of dental impression materials are considered to be the introduction of dental trays in Over the last 100 years, elastomeric impression materials were continuously developed and optimized for improved precision, patient comfort and ease of use. Scribd is the world's largest social reading and publishing site. Since ethyl alcohol is the by product they are dimensionally stability is poor and they should be poured immediately after the removal from the mouth. Lawson, DMD, PhD; and John O. impression materials. Available in liquid or aerosol spray. Any moisture results in voids. Cendres Métaux SA 290,329 views The simplest method of classifying impression materials is by key properties: (A) rigid, [CLICK] (B) water-based, and [CLICK] (C) elastomeric. BIOCOMPATIBILITY These materials are highly biocompatible. They are more dimensionally stable on storage. The most widely used impression materials are elastomeric polymers. • 1973 First moldable acrylic material. Elastomeric Impression Materials; 2. [Elastomeric impression materials]. impressions. Reversible. A sectional impression, whether with irreversible hydrocolloid (alginate) or vinyl polysiloxane (silicone) or a combination of impression materials, can be useful to customize a stock tray to record the landmarks of the palatal surface of the maxillary arch. For the universal Pentamix System, there is the complete range of 3M ESPE impression materials: polyether and silicones for precision impressions, and an innovative A-silicone for alginate indications. elastomeric impression materials ppt