Adhesion of resin materials to tooth structure has been a challenge in the history of adhesive dentistry. Currently, bond durability is one of the main research topics in adhesive dentistry. Regardless of the improvements in bonding technology, resin dentin bonds show limited durability for both etch and rinse and self-etch adhesive systems. The main problem concerning the durability of resin-dentin is the hydrolytic degradation of the two components of the hybrid layer. These are the collagen matrix and the adhesive resin [8]. Many approaches to enhance long-term bonding were developed , these include the inhibition of dentinal endogenous proteases (matrix metalloproteinases and cysteine cathepsins)[22].Matrix metalloproteinases are thought …show more content…
Because of its ability to break down self-associative tendency of water , it may also reduce the number of water molecules entrapped between the polymeric chains, increasing the degree of postoperative polymerization In addition to post-curing increase in bond strength, the relative decrease in free water would eliminate or decrease the hydrolytic degradation of adhesive in or above the hybrid layer …show more content…
This positive effect was attributed to improved wetting of collagen by the adhesive [21] In the same study Tjaderhane suggested that, a considerably low concentration of dimethyl sulfoxide was shown to reduce dentin bond strength loss after aging. Considering di-methyl sulfoxide properties, higher concentrations might have a positive effect on dentin bonding. [21] Stape et al also found that dentin pre-treatment with low dimethyl sulfoxide concentrations improves long-term bonding at the expense of an extra step in the etch-and-rinse bonding technique. Therefore, solvation of adhesive monomers by dimethyl sulfoxide could possibly benefit dentin bonding in a similar manner, but without the need of an extra bonding step, as long as the resin mechanical/physical properties would not be compromised.
Khosravi K, Ataei E, Mousavi M, et al. Effect of Phosphoric Acid Etching of Enamel Margins on the Microleakage of a Simplified All-in One and Self-etch Adhesive System. Operative Dentistry 2009; 34(5):531-36.
...at more tentatively, with fluoride gels and varnishes or a chlorhexidine varnish. Some dentists may restore root caries with amalgam restorations. Another treatment option used by some dentists to restore root caries is Glass Ionomer Cements. Glass ionomer cements were first introduced in the early 1970s. They have good adherence to mineralized tooth tissue, which keeps the removal of tooth structure to a minimum. Glass ionomer cements also have the ability to leak and absorb fluoride into the tooth, which decreases the rate of secondary caries. These factors have increased the potential for glass ionomer cements to replace amalgam as a restorative material. (Hammel)
Dr. Gary Silva and his team are highly trained and experienced in providing restorations for all sorts of dental issues. We offer complete and partial dentures, tooth-colored fillings, crowns, bridges, and more. Dr. Silva’s unique background gave him real restorative experience early in his career. For more than 20 years, Dr. Silva has been offering patients the chance to gain a beautiful, functional smile with his restorative dentistry.
Positive results have been seen on periodic checkups and most of the patients didn’t complain. One patient suffered from plaque deposition on abutment teeth due to insufficient oral hygiene. Gold copings protect root surface but are expensive which makes the treatment overall expensive. Most of the time canines are used as abutments because they are frequently the last teeth to be lost in the jaw because of their large root surface
The biggest shortcoming of these archaic appliances was the fact that they were subject to decay in the wearer’s mouth. Thus, installed false teeth would have to be replaced on a regular basis, resulting in a very costly procedure. However, this problem was rectified in 1774 by Duchateau and Dubois de Chemant with their invention of the first full set of dentures that would not rot. This was due to their porcelain composition – a material that was much more conducive to the everyday wear and tear of one’s teeth. Although an incredible improvement, even the porcelain version had its difficulties. Unable to produce anything less than a full set of teeth (the surrounding porcelain was required to keep each tooth in place), patients who were missing only one or two teeth were out of luck, unless they were willing to have the rest of their teeth removed as well. And yet, in 1808, Giuseppangelo Fonzi developed the first individual appliance – a single porcelain tooth that could be held in place by a pin drilled into the jawbone. Finally, in 1845, Claudius Ash, known as the official “inventor of dentures”, produced the porcelain version that is now used today. His contributions included a suction method of adhesion for a full set of dentures, so that no form of attachment could be seen by an onlooker.
Improper nutrition and misbalance in our body may be the causes for tooth decay. Always pay attention to your nutrition when your teeth are considered, instead of choosing fluoride or dentistry. Our health can also be in danger when fluoride is used, even though the main reason for using fluoride is to make the teeth stronger. According to a recent study, mental disabilities are often made more difficult with the usage of fluoride. Among fluoride, mercury and arsenic are also dangerous in cases of autism
In answering the PICO question, silver diamine fluoride is more effective at arresting dentinal caries than sodium fluoride varnish. In reviewing these research studies, SDF is an affordable, effaceable alternative to restorative treatment that can be particularly helpful in areas without much dental personal, equipment, or facilities. Further study is needed to determine the recommended interval, exact application, and longer term outcomes. In conclusion, research suggests SDF would be a great carries treatment solution for people around the world, especially those in disparity groups.
Dental sealants are composed of plastic as a result, they will eventually wear down with use. However, eating hard foods can speed
These kinds of polymers have both some advantages and disadvantages. Although they are bioactive and biodegradable and provide high comppressive strength, Degradation of such polymers leads to undesired tissue response due to producing acid formation in degradation process. Metallic scaffolds are another method for bone repair and regenaration. They provide high compressive strength and enormous permanent strength. Metallic scaffolds are mainly made of titanium and talium metals. The main disadvantages of metallic scaffolds are not biodegradable and also discharge metal ions. Recent studies in metallic scaffolds mainly focus on biodegradable materials which can be used improve bioactivity of metals such as titanium.
Denture teeth can be made of acrylic poly(methyl methacrylate) (PMMA) or composite resins. PMMA is a polymer - a material made the from joining of methyl methacrylate monomers. Properties of PMMA include resistance to abrasion, chemical stability and a high boiling point. (Jun Shen et al. 2011). However, weak flexure and impact strength of PMMA are of concern as they account for denture failure. (Bolayir G, Boztug A and Soygun K. 2013). Composite denture teeth are made of a three distinct phases - filler, matrix and coupling agents. Out of the types of composite teeth available, nano-filled composite teeth are preferred. Composite teeth have a PMMA coating around the tooth and a high content of filler particles. This gives them strength, higher resistance to forces than acrylic teeth and provides compete polymerization due to the PMMA coating. (Anusavice, K. J., Phillips, R. W., Shen, C., & Rawls, H. R, 2012). If the interface between the PMMA denture base and PMMA or composite teeth was weak, the denture will not be able to sustain occlusal forces, making the base-teeth interface, an entity of significance.
chains instead of hydrogen atoms. Cross-linking is another way in which the polymer can be made stronger. This involves ultraviolet radiation that bombards the polymer with electrons and formulates bonds between the molecular chains of the polymers. This is like linear polyethylene but different in that it is more impact resistant, and it has a much higher density. This allows it to be stored or be used with different chemicals that would normally cause the polymer to desolve.3 This can start to become a problem because as the polymer continues to become chemically enhanced. So the ways of dissolving and recycling the polymer become more difficult.
Impression materials are used to register or reproduce the form and relations of the teeth and the surrounding oral tissues (1). Making an impression represents a critical step in processing and fitting of a dental prosthesis (2). Several types of impression materials are produced. These include silicones, polyether, polysulfide and alginate which are available for crowns and fixed partial denture impressions. Silicone impression materials are considered to be suitable impression materials to use for fixed prostheses (3). Also, it has been reported that silicone has the ability to remain dimensionally stable through disinfection procedures (4). Among silicone impression materials, one type of them, called polyvinyl siloxane (PVS) is reported
11. Bagis YH, Baltacioglu IH, Kahyaogullari S. Comparing Microleakage and the Layering Methods of Silorane-based Resin Composite in Wide Class II MOD Cavities. Oper Dent. 2009; 34(5): 578-585.
Advanced technologies have been discovered for repairing the distorted metal framework of the removable partial denture such as the laser welding technology which has had an effective role in fixing the framework by soldering techniques. There are two types of welding which are conduction and spot welding, spot welding is the most commonly used type especially when it comes to the laboratory procedures. There are some conditions that must be done and taken into consideration to achieve efficient welding such as the area being welded, the depth of welding and the intimate contact between objects being welded together. There are different types of lasers, the type of alloy being welded determines the specific type of laser needed for welding this specific alloy.(6)
Gandolfi MG et al 11 studied on chemical, physical properties of TLC and reported more calcium release than Pro-Root MTA and Dycal. It was reported that calcium silicate based materials showed apatite formation at a faster rate than calcium hydroxide based materials.12 However, there are contradictory findings reported in literature about the hydration characteristics of TLC.13 The role of moisture drawn in from the pulp and dentin is also unclear. TLC shows physio- chemical bonding to dentin and is well tolerated by immortalized odontoblast cells 14. Recently, Cantekin K15 proved that the bond strength of Theracal – methacrylate based composite was significantly higher than that with silorane-based composites and glass-ionomer cement. Currently, there is limited information in the literature on bonding ability of TLC to RC in comparison with other