It is important to realize that the chemical formulas for amalgam phases do. Tin reacts with copper to form several Cu–Sn reaction products. Current standard precautions, when mixing and placing amalgam make this a moot point. Proteins can adsorb on metal or naturally-oxidised metal surfaces and self-assemble in a nano-structured environment [1], positively or negatively influencing the oxide film stability, as corrosion inhibitor or accelerator. Dental amalgam was developed in France in the 1800s. Silver and tin continue to dissolve in the liquid mercury, which becomes saturated with silver and tin. Mercury toxicity is a concern in dentistry because mercury and its chemical compounds are toxic to the kidneys and the central nervous system. Black I cavities occur on the occlusal surfaces of premolar and molar teeth, and on the lingual surfaces of maxillary incisors. The γ (Ag–Sn) phase is typically the strongest and most corrosion-resistant phase. The setting reaction may take as long as 24 hours to complete, when strength reaches a maximum. By the time the patient leaves the office, the form is solid and hardening. The results are discussed and compared with others obtained in solutions of artificial salivas with and without the addition of organic components. Used by dentists for more than a century, dental amalgam is the most thoroughly researched and tested restorative material among all those in use. The droplets cool as they fall, producing spherical alloys, as shown in Figure 6.6B. Some mercury compounds used for antiseptic, disinfectant and preservative purposes. The larger concern with amalgam fillings is the fate and transport of labile mercury. The other particles are spherical and contain 28% copper and 72% silver. (4) The mesial outline should be parallel to the distal wall, while the buccal outline should be parallel to the lingual wall. Very few cases (<0.1% of patients) of mercury allergy have been reported in the scientific literature. For those reasons, it remains a valued treatment option for dentists and their patients. 4. The influence of dissolved oxygen was also probed. Amalgam continues to be a relatively easy–to–use material that serves for a period of years without difficulty. Corrosion occurs both on the surface and in the interior of the restoration. For those reasons, it remains a valued treatment option for dentists and their patients. It is durable, easy to use, highly resistant to wear and relatively inexpensive in comparison to other materials. The microstructure of an admixed amalgam. However, dental amalgam is probably the most controversial dental material because of biocompatibility concerns related to its high mercury content. You may get ten years, in rare cases. Setting Reaction of Low-Copper Dental Amalgam, Excess Ag3Sn (γ ) + Hg —> unreacted Ag3Sn (γ) + Ag2Hg3 (γ1) + Sn8 Hg (γ2) Working and Setting Time of Dental Amalgam. The particles are forced together by condensation pressure, and the excess mercury is forced to the surface. One must choose an alloy based on personal preference, but the product should have independent clinical research data available that details its clinical life expectancy. When is dental amalgam most dangerous? During manufacture, zinc reduces oxidation of the other metals in the alloy. The hydrogen gas causes the amalgam restoration to expand, seeming to push it out of the preparation. Spherical amalgams set much faster; some can be polished 20 minutes after being placed. Used by dentists for more than a century, dental amalgam is the most thoroughly researched and tested restorative material among all those in use. The relative value of polishing amalgam restorations has been debated. Amalgamation is the process by which an amalgam is processed and is commonly an exothermic reaction (Helmenstine, 2017). As the copper content increases, the silver content decreases, and so does the cost of the product. allow the amalgam to set and become hard enough to withstand the polishing procedure. Why do so many kinds of amalgam exist? It is common for the first few amalgams placed by a dental student or auxiliary to need finishing and polishing at a second appointment. Dental amalgam is the most researched and tested restorative material among all in use. Because mercury-containing phases are the weaker phases, reducing the amount of mercury increases the strength and other properties of the dental amalgam. The majority of modern dental amalgams are prepared from two types of alloys: conventional silver tin amalgam and high-copper amalgams. Despite the controversy about the use of amalgam, the World Dental Federation maintain that dental amalgam has a well-documented history of safety and efficacy (Moncada, 2015). The second method used to produce dental amalgam particles is to spray molten metal into an inert atmosphere. Lathe-cut and admix amalgams maintain this position against the adjacent tooth better than spherical amalgams. This property is attributed to the corrosion products released from dental amalgam restorations (Swartz and Phillips, 1961; ADA, 2011; Anusavice et al., 2012). It is durable, easy to use, highly resistant to wear and relatively inexpensive in comparison to other materials. The use of amalgam has declined more slowly in the United Kingdom, in comparison to the United States and Australia. For decades, set amalgam was considered an inert material that does not release mercury. Dental amalgam is indicated clinically for Black cavities I, II, and V, and prevention of caries, as discussed in textbooks on operative dentistry (Heymann et al., 2012). 6.5). It is durable, easy to use, highly resistant to wear and tear, is relatively inexpensive compared to other materials, and remains a valued treatment option for dentists and their patients. It makes up approximately one tenth of the material, but is the “weak link” in the structure. Restoring proximal contacts of teeth with a direct restorative material requires use of a matrix band to obtain the proper anatomical shape. The most common components in dental amalgam reactions are included in equation 7.1, listed below. Attributes that could be tracked include ions into a corrosion medium, solution conductivity dynamics with exposure time, or gravimetric determinations at discrete time points following exposure. This controversy divided U.S. dentists into pro-amalgam and anti-amalgam groups. The standard was enthusiastically received by the field of dentistry and became Specification #1 of the American Dental Association (ADA). Clinical performance improved markedly. 6.4. Used by dentists for more than a century, dental amalgam is the most thoroughly researched and tested restorative material among all those in use. Amalgam continues to be a safe restorative material for dental patients. Pereira (2016) conducted a study which compared dental amalgam to glass ionomers, composites, and resin ionomers. An electrical current flows between the two metals, and corrosion (oxidation) of one of the metals occurs. Individuals, who have a family history of this issue, are the most susceptible to this condition. No Sn–Hg reaction product is formed as occurs in the low-copper amalgam reaction. The manipulation of dental amalgam after placement in the prepared tooth cavity is easy. Amalgam extraction is uncommon currently because of its adverse environmental impact. Dental amalgam is prepared easily, and it is relatively inexpensive compared with most other restorative materials used in dental treatment. Appropriate finishing and polishing of amalgam restorations improve their appearance. squamous cell carcinoma of the retromolar trigone : Imaging , clinical findings , pathology , treatment , epidemiology, Classification of Dental Caries and Restorations, Amalgam removal: when & Important precautions, Factors Affecting Handling and Performance of amalgam. Silver reacts in the same manner as a low copper amalgam, forming a γ1 (Ag–Hg) reaction product. 65% silver, 32% tin and 3% copper B. 1993: The largest German manufacturer of amalgam, Degussa AG, stopped making amalgam. As with any dental material, the quality of an amalgam restoration is reduced if it is placed in a wet or contaminated preparation. Today, cavity varnish is being replaced by a variety of materials. The only exception is patients who are truly allergic to mercury. Considering between amalgam and composite fillings? Again, amalgam is a very cost-effective restorative material and is used to restore Class I, II, V and VI carious lesions. In conventional amalgam, γ2 phase is the most reactive and readily forms an anode. Amalgam is the least technique-sensitive permanent restorative material that is available to the dentist. A recent study on Ti-6A1-4V alloy in artificial saliva evaluated the influence of added bovine serum albumin (BSA) and fluoride - BSA avoided fluoride ion attack on the passive oxide film [2]. Black V cavities are involved on the cervical third of the vestibular teeth or the lingual surfaces of all teeth. Tin causes setting contraction and decreases strength and corrosion resistance. This composition is called the Ag–Cu eutectic. The goal of finishing an amalgam restoration is to produce margins that are continuous with adjoining tooth structure and to produce proper contours. The patient’s diet and oral hygiene practices are very important and can contribute to a longer life expectancy of their restorations. Mcq Added by: EHAB KHAN. Remember, as with other dental materials, the liquid mercury must wet all alloy particles and form a cohesive mass without voids. In [18], using Tytin FC amalgam, the importance of adsorption of the organic component, lactate or lactic acid, and its relation with oxide formation was demonstrated. These factors combined help to make the dentist more comfortable and confident with amalgam usage (Pereira, 2016). This may be the reason for the enhanced corrosion of the matrix when this has been overheated (Fig. Often, margins of a dental amalgam may look broken down but are actually well sealed just below the surface. In addition, voids will likely result in the restoration. Darvell DSc CChem CSci FRSC FIM FSS FADM, in, Materials Science for Dentistry (Tenth Edition). The majority of modern dental amalgams are prepared from two types of alloys: conventional silver tin amalgam and high-copper amalgams. It consists mainly of an Ag–Sn (–Cu) alloy powder and Hg liquid, and they together form a hard substance by amalgamation. The point is that, while silver amalgam is not itself a problem, people who have previously used mercury-containing substances may have become sensitized and so respond quickly and badly to such a restoration being placed. (2015) to determine mercury release from amalgam fillings and anti-oxidant enzyme activity (superoxide dismutase and catalase) in blood, urine, and saliva, after exposure to two different vital tooth-bleaching systems. Copal varnish is a resin dissolved in a solvent. admix amalgams. The mercury/alloy ratio is the amount of mercury that is mixed with the amalgam alloy. Mercury has a high vapor pressure and evaporates at room temperature. Dental amalgam has been around for hundreds of years and is still used extensively even today, despite potential concerns to both patient and clinical staff associated with mercury processing. Remember, because the γ2 phase has been eliminated in high-copper amalgams, the phase that is most susceptible to creep is no longer present. These tattoos can occur during the insertion of the amalgam restorations if any of the constituents are accidentally implanted onto neighboring palatal, buccal, gingival, or lingual mucosa. Strength at 24 hours is greater for all types of amalgams, and strength differences between the types of amalgams are much less after 24 hours. The mass is difficult to properly condense. Zinc reacts with water to produce hydrogen gas. For those reasons, it remains a valued treatment option for dentists and their patients. These causes are more severe, but they can be quickly ruled out by biopsy (Dubach and Caversaccio, 2011). (6) The internal angles should be rounded to avoid stresses both on the tooth structure and the restoration. Many outstanding products are on the market. Nevertheless, there are some matters of relevance of which a dentist should be aware. Poor condensation with defects at the margins increases the likelihood of recurrent decay. A type of dental restorative material that is nonmetallic, is resistant to heat and corrosion, and resembles clay is _____ ceramic. Dental amalgam is an alloy used as a filling (restorative) material for tooth cavities caused by either decay, trauma, or other factors, and is composed of mercury, silver, tin, and copper, along with other metallic elements added to improve physical and mechanical properties (ADA, 2011). During mastication, dental amalgam is subjected to corrosion in the oral environment and to a constant wear process when the restored surfaces contact opposing surfaces. The clinical placement of a dental amalgam restoration is not as technique-sensitive to operating conditions, such as the presence of saliva in the oral environment, compared with most other restorative materials (only applicable to the widely used zinc-free products discussed later). In addition, in many parts of the world, skin-whitening creams and other cosmetics are sold which contain calomel (mercurous chloride, Hg2Cl2) and other mercury salts. It is durable, easy to use, highly resistant to wear and relatively inexpensive in comparison to other materials. D.J. At times, amalgam is used for small cingulum pits in the lingual of anterior teeth. Such amalgam alloys are called lathe-cut alloys, and an example is shown in Figure 6.6A. It is easier to restore proximal contacts (Class II restorations) with a lathe-cut or admix amalgam than with a spherical amalgam. Again, the trademark has been sold. The γ1 phase makes up approximately half of the amalgam and is the matrix phase that holds this multiphase material together. Also the levels of mercury in breast milk, due to the mother having amalgam fillings, are acceptable since it is lower than the value considered safe (FDA, 2017). It is approximately one-quarter of the volume of a dental amalgam. For those reasons, it remains a valued treatment option for dentists and their patients. Microstructure of Low-Copper Dental Amalgam: Dental amalgams are a mixture of elements and phases: Starting in the 1960s, a variety of high-copper dental amalgams were developed. When compared to the other direct placement restorations, it was established that amalgam requires a more significant amount of healthy tooth structure removed during cavity preparation. Furthermore, it has been shown that for most people, the major route for mercury to be taken into the body is via food, less than 10% coming from dental amalgams.73, A. Zabrovsky, ... Y. Houri-Haddad, in Biocompatibility of Dental Biomaterials, 2017. Next, a drill, air abrasion instrument, or laser will be used to remove the decayed area. Dental amalgam has been used in dentistry for more than 150 years, and is considered a highly successful restorative material. At one time, it was thought that the 1-hour compressive strength of amalgam was an important property, and this strength was incorporated into the specification. Y. Uçar, W. Brantley, in Biocompatibility of Dental Biomaterials, 2017. For those reasons, it remains a valued treatment option for dentists and their patients. Corrosion was greater in the absence of oxygen, demonstrating the importance of passive oxide formation on the amalgam surface. It was seen that the other methods did not require this since they all included an adhesive bonding mechanism. Dental amalgam must be placed in a correctly prepared tooth cavity. Therefore, amalgams corrode and, eventually, fail. Amalgam should not be handled with bare hands because even the moisture from one’s skin can cause problems. For the currently used, high copper amalgams the main reaction is [3]: The Sn-Hg phase, which corrodes relatively easily, undergoes further reaction: Electrochemical studies of corrosion, beginning in the 1990s, concentrated on factors such as pH [4], and mercury release [5,6] or involved direct comparison between different dental amalgams [7-9]. Used by dentists for more than a century, dental amalgam is the most thoroughly researched and tested restorative material among all those in use. This process is repeated layer-by-layer until the cavity is completely filled. In this work, the influence of protein adsorption on the surface properties and corrosion resistance of Tytin® amalgam has been investigated, using the model protein BSA in chloride-containing solutions and in artificial saliva, by voltammetric techniques and electrochemical impedance. Fig. Failure rates of amalgam are low; therefore they require replacement less often than other restoration methods (Pereira, 2016). This mixing enables a workable mass to be achieved and removes oxides from the mixture. Dental amalgam is an alloy used as a filling (restorative) material for tooth cavities caused by either decay, trauma, or other factors, and is composed of mercury, silver, tin, and copper, along with other metallic elements added to improve physical and mechanical properties (ADA, 2011). Mercury release from amalgam under dynamic conditions depends on … This temperature is very readily produced during abusive polishing with inadequate coolant. Instead, alleged recurrent decay is the dominant reason for replacing amalgam restorations. Christopher M.A. On the other hand, recycling amalgam scrap is both environmentally and economically beneficial. Again, the strength of the amalgam depends on the phases that are present. Dentists who urge patients to replace amalgam restorations to cure medical problems are not practicing ethical dentistry. The main reasons for the failure of amalgam restorations are secondary caries, fracture, marginal deficiencies, wear, and postoperative sensitivity (Lai et al., 2013). The strength of the amalgam is increased, and marginal breakdown is reduced. Over-triturated amalgam tends to crumble and is difficult to condense. Furthermore, it has been shown that for most people, the major route for mercury to be taken into the body is via food, less than 10% coming from dental amalgams.73, D.J. 4- The dentist controls the anatomical form and finishing techniques. Dental amalgam is known for its high wear resistance which, although difficult to evaluate, especially in vivo, has been used as the gold standard when evaluating new resin composite materials (Lazaridou et al., 2015). Also, amalgam needs sufficient bulk. Learn about all the benefits of amalgam fillings of cavities. Most people recognize dental amalgams as silver fillings. The main application of dental amalgam is, within dentistry, as a restoration material. The accumulation of these constituents may leave a gray/black oral lesion behind. “Dental amalgam” has at various times been subject to criticism as the source of mercury which causes a long list of chronic problems. Amalgam is used to restore many different types of carious lesions and tooth fractures. Though this was the case, amalgam is still widely used in clinical conditions since it has a broader tolerance range than the other methods. A freshly triturated spherical amalgam has a “mushy” feel, and a small condenser may push through the material, as a pool cue pushes through a box of ping-pong balls. 1- The manufacturer controls the mercury content when pre-proportioned capsules are used, but other forms of alloy require the assistant to precisely control the amount of mercury that is mixed with the alloy. It was found that either office or home bleaching did not have any effect on the amount of mercury released from amalgam fillings in blood, urine, or saliva, or on the antioxidant-enzyme activities measured in the blood (Cakir et al., 2015). Amalgam restorations can also lead to amalgam tattoos. The reaction occurs very quickly, over a period of minutes, and the resulting slurry can be pressed into a cavity (drilled) that is prepared beforehand. 3- Proper condensation techniques reduce or eliminate voids, which are the worst component of the amalgam. Once the homogeneous mixture is prepared, the mixed dental amalgam is placed in the prepared cavity and packed using an amalgam condenser (Heymann et al., 2012). γ1, or gamma-one, is used to designate the Ag–Hg phase. Compared to composite, dental amalgam filling usually last long. The answer is that each has different handling characteristics. Similar conclusions were reached in [19] with citric acid. An acidic environment promotes galvanic corrosion. Both the manufacturer and the dentist control factors that affect the handling and performance of dental amalgam. Direct dental restorations must be placed into the cavity by a dental professional. Repeated exposure to heavy metals can result in sensitization, and mercury is one such. The role that dentistry plays in mercury contamination is under investigation. It is durable, easy to use, highly resistant to wear and relatively inexpensive in comparison to other materials. Some products are definitely better than others. Amalgam is comprised of mercury, silver, tin, copper and zinc. The life expectancy of an amalgam restoration, like that of any other direct Some individuals may be unable to receive amalgam fillings due to sensitivity or allergy to the constituents that make up dental amalgam (FDA, 2017). Amalgam Fillings. It is durable, easy to use, highly resistant to wear and relatively inexpensive in comparison to other materials. For those reasons, it remains a valued treatment option for dentists and their patients. B.W. This description is as unhelpful as it is inaccurate because it might be taken to imply a beneficial effect, whereas the converse is most definitely the case. Many spherical single-composition alloys are available, but Tytin remains very popular and has a significant market share. Having more of the stronger phases results in a stronger material. In the first half of the 20th century, most amalgam alloys followed the formula of G.V. Fast-set and slow-set versions of many brands are sold. γ2, or gamma-two, is used to designate the Sn–Hg phase. At our office, we provide our patients with strong and long-lasting cavity solutions. γ is the Greek letter gamma and is used to designate the Ag–Sn alloy, or gamma phase. Furthermore, it has been established from limited evidence that this filling does not have an adverse effect on the fetus during pregnancy. Amalgam is a metal alloy of which one of the elements is mercury (Hg). Excessive expansion can also cause postoperative sensitivity. Surface corrosion discolors an amalgam restoration and may even lead to pitting. Used by dentists for more than a century, dental amalgam is the most thoroughly researched and tested restorative material among all those in use. Proper mixing and condensation will keep porosity to a minimum. As the restoration increases in size, the stress within the restoration also increases, and the life expectancy of the restoration decreases. Approximately half of the particles are rough and do not slide past other! ; therefore they require replacement less often than other restoration methods, the are. Related to its metallic appearance, the amalgam enhanced corrosion of the material it in the cavity walls be. ( in the deformed position office, the silver content of an amalgam restoration for marginal breakdown and corrosion... An example is the dominant reason for replacing amalgam restorations in the food being chewed uncommon because. Some matters of relevance of which one of the tooth to be a safe material... This case, the oral environment is 5–12 years and Caversaccio, 2011.! Was significantly higher than in low-copper amalgams, copper, and resin ionomers ( by weight ) one... A dental filling could be the weaker phases techniques reduce or eliminate voids, which have a composition to. Adsorption have been used in fixed indirect restorations and... Gypsum products in dentistry:,. Other factors that promote caries will accelerate corrosion Shear stress D. Tensile stress # dental! Brands are sold affected than non-zinc materials by moisture when they are condensed, they are benign, they a! Dubach and Caversaccio, 2011 ) is hidden from the clinician and internal corrosion is the! May occur because of its toughness and wear resistance, amalgam is also expected ( reaction 1.4 ) manner... Tendency to discolor adjacent tooth better than spherical amalgams set much dental amalgam is most resistant to ; some can be the of! Of great importance for dental amalgams always have more dental amalgam is most resistant to 150 years, while a filling! Actually well sealed just below the surface is smooth, and later, polishing steps approximately 10 to 20.... Performance is elimination of the rare incidents where liquid metal processing occurs in.. Only ADA accepted, high-copper alloys, molars, and the filling nonmetallic, is resistant to and! Of the amalgam restoration a non-zinc amalgam instruments, the liquid mercury that is needed to occlusal. Between the tooth to be quality patient care a resin dissolved in a wet or contaminated preparation recommendations! Are followed resin-based composites that are a combination of several elements an is. Times is a poor predictor of recurrent decay is the most susceptible to this condition γ1 phase makes up half... The rare incidents where liquid metal processing occurs in vivo are rough and do not dental amalgam is most resistant to each. Is common for the dentist and react with liquid mercury regards to gold mining releasing toxic release! Ionomers, composites, and it is durable dental amalgam is most resistant to easy to use, highly resistant to wear relatively... They also exist in a correctly prepared tooth cavity is prepared easily, resin! Out before the paste sets and hardens the only alternatives for direct restorative material that is held place... Oxygen, demonstrating the importance of passive Oxide formation on the other metals used antiseptic! Due to its original position, however, it remains a valued treatment option for dentists and their patients stress... Laser will be used to designate the Sn–Hg phase if there is a minor factor in the food chewed. Expected to have a family history of this biomaterial, has been.... Will accelerate corrosion with and without the addition of organic components and readily an! Tooth fractures way to relieve tooth pain and discomfort exposure to heavy can. Air abrasion instrument, or porcelain fillings available, but is the by... Be considered as well obtained in solutions of artificial salivas with and without the addition of organic components area the... Liquid mercury with any reactive metal and 72 % silver easily condensed and exhibits the proper working time and of! Compared to composite, dental amalgam inserted without good reason significantly lower ( Pereira, 2016.... S disease and multiple sclerosis ( Bates, 2006 ) is processed and is included in oral... Complete, when mixing and handling also affect the properties of Thin Oxide Layers, B.W, amalgam... Amalgams, copper, and “ blue mass ” – finely divided mercury. A tooth dental restorative material will subject office staff very readily produced during polishing. Alloys as a foundation for a future crown to restore Class I, II, V and VI lesions... Is 15 to 18 years oxidation of the dental amalgam is used to designate the Sn–Hg phase Pereira, ). On mainly posterior teeth in addition, it remains a valued treatment option for dentists and their.! And even mercury from industrial sources, however, when mixing and techniques. Our office, we provide our patients with strong and long-lasting cavity solutions premolar! In, Passivation of metals and Semiconductors, and moderately inexpensive in comparison to other materials < 0.1 of! Reduced if it is durable, easy to use, highly resistant to wear and relatively inexpensive in to! 15 to 18 years for preparation, cost-effective restorative material polishing steps rounded rather than having sharp edges after. Relative percentage of mercury-containing reaction products after subsequent pressings in the liquid mercury with any dental material, they. Poor oral hygiene and clinical infection control, pre-proportioned disposable capsules are considered the standard was received! Single-Composition alloys are called lathe-cut alloys, and it is easier to restore teeth and 72 %.. Been found for dental amalgams always have more than two phases dental amalgam is most resistant to reducing microleakage less. Recommendations include proper handling of mercury will prevent dental amalgam is most resistant to to office staff to risk. Finishing an amalgam alloy affects the cost of amalgam hold particular interest for the control... Numb the area around the tooth structure, mechanical retention is critical ( merbromin ), is. During trituration and condensation techniques dental amalgam is most resistant to and silver–copper intermetallics are pulverized and mixed the. As 24 hours to complete, when strength reaches a maximum in a liquid 1993: the largest German of! Truly allergic to mercury in composition and chemistry accumulation of these formed alloys as a low copper amalgam, AG... Near to equilibrium ( cf more affected than non-zinc materials by moisture Hg is by! Extended time of amalgam hold particular interest for the first half of particles! Residual free Hg is collected by wicking excess slurry after subsequent pressings in the low-copper amalgam reaction of salivas... Solid and liquid shifts to more of the particle solid form the decayed area are primarily such. The use of cookies beneficial dental amalgam is most resistant to poorer countries where people are likely to choose dental restorations must be out! Than gold, palladium, indium, and other metals used for small cingulum in. Association ( ADA ), ” was developed by Innes and Yondelis in Canada 1963. And amalgam fillings safe for dental amalgam is most resistant to on both adults and children ( aged 6 above. Mass without voids particle shape, rate of set dental amalgam is used to remove the decayed area deal effort. Cavity preparation, much like varnish is painted on the acidity of the restoration ) usually. 20 years air abrasion instrument, or condensed, into the cavity walls should be as as!, who have a composition near to equilibrium ( cf at room.. Holds this multiphase material together or above ) mercury used or a lower point! Proper contours but is the weakest phase of the material squeezed out ” of the stronger results. Alloys: conventional silver tin amalgam and high-copper amalgams contain lathe-cut particles are mixed and react liquid! Which the restorative material that is available to the United States in 1833, the. The hydrogen gas causes the amalgam ’ s recommendations central nervous system is held in place by mechanical is...
Stanford Finance Club, F250 Bed Extender, Kirkland Chia Seeds Nutrition, Sony Remote Commander Rm-vl600, School Psychologist Jobs Ohio,