Restorative Materials

Amalgalm Restorations

• Amalgam offers the best retention for pin restorations due to its strong mechanical properties and longevity. [Q0454]
• High copper amalgam is more corrosion-resistant than low copper amalgam, contributing to its longer lifespan. [Q0459]
• Low copper lathe-cut alloys are more prone to creep, which is the slow deformation of amalgam under stress over time. [Q0719]
• Amalgam is often preferred for core build-up in posterior teeth due to its strength, durability, and ability to withstand occlusal forces. [Q0927]
• Amalgam pins typically have a diameter of 1mm, providing strong retention in restorations. [Q3223]
• Copper in amalgam significantly improves marginal adaptation and resistance to corrosion, enhancing the restoration’s longevity. [Q3524]
• Copper is added to amalgam to provide extra strength, making the restoration more durable. [Q3525]
• Copper is added to dental amalgam to increase its strength and reduce corrosion, improving the material’s performance. [Q5639]
• More tin is added to amalgam to increase its working time, allowing for better manipulation during placement. [Q5801]

Bonding

• Enamel surface does not conform perfectly to bonding requirements without proper preparation, such as acid etching. [Q0717]
• Phosphoric acid etching is necessary for dentine bonding, similar to enamel, to create a suitable surface for adhesive bonding. [Q3582]

Cement Manipulation

• Cooling down the mixing slab prolongs the setting time of glass ionomer cement by slowing the chemical reaction. [Q0157]
• Glass ionomer cement sets due to an acid-base reaction between the powder and liquid components. [Q0300]
• Zinc oxide-eugenol (ZOE) is commonly used for temporary cementation due to its easy removal and sedative effect on the pulp. [Q0463]
• Glass Ionomer Cement (GIC) is less soluble in the oral cavity compared to other cements, making it more durable. [Q0467]
• The bonding between enamel and glass ionomer cement is strong due to chemical adhesion, enhancing the retention and stability of restorations. [Q3375]
• GI cement is more resistant to erosion than Zinc phosphate, making it more durable in the oral environment. [Q3818]
• GIC is considered the best lining under metal cast inlays due to its adhesive properties and fluoride release. [Q3820]
• Radiopacity in GIC allows for better visualization under X-rays, making it easier to monitor the restoration. [Q3821]
• Glass ionomer cement is hard, durable, adhesive to enamel and dentin, and useful in anterior teeth because of its good appearance. [Q3829]
• Glass ionomer cement is suitable for anterior teeth due to its hardness, durability, and adhesive properties. [Q3830]
• Resin cement is typically used for cementing porcelain veneers due to its strong bonding properties. [Q4871]
• Resin cement has the highest compressive strength among dental cements, making it suitable for load-bearing restorations. [Q6020]
• Zinc oxide and eugenol are the components of this dental material, commonly used for temporary restorations. [Q6131]
• Zinc oxide and eugenol cement is commonly used for temporary restorations due to its easy handling and sedative properties. [Q6132]
• Zinc oxide and eugenol pastes are bactericidal, providing an antimicrobial effect in temporary restorations. [Q6133]
• They are always used in temporary restorations without load on occlusal surfaces, ensuring patient comfort and material integrity. [Q6134]
• Zinc phosphate cement is soluble in saliva, which can compromise its integrity, making it less suitable for situations with high salivary exposure. [Q6135]
• Zinc-oxide eugenol is used as a temporary restorative material in dentistry, providing a sedative effect on the pulp. [Q6136]

Composite Resins

• Hybrid composite resins contain microfill particles that enhance their wear resistance, making them suitable for posterior restorations. [Q0211]
• Microfill resins typically have a higher coefficient of thermal expansion and lower crushing strength, affecting their performance in restorations. [Q0294]
• Zinc oxide and eugenol (ZOE) can inhibit the polymerization of composite resins, making them incompatible for use together. [Q0325]
• Class III resin restorations typically last the longest due to lower occlusal forces, making them more durable in anterior teeth. [Q0453]
• A high concentration of filler particles in composite resin increases its strength and wear resistance, enhancing the longevity of the restoration. [Q0478]
• Hybrid composites provide the best resistance to fracture at the acid-etched tooth-composite interface, making them suitable for small incisal fractures. [Q0479]
• A high filler content is essential for composite resins used in load-bearing areas to ensure sufficient strength and wear resistance. [Q0542]
• Hybrid composites, which contain a mixture of different sized filler particles, provide the strength and wear resistance needed for load-bearing areas. [Q0778]
• Resin-based materials are commonly used in composites, providing a strong and durable restoration. [Q3828]
• Micro-filled composites offer better polishability while larger filler particles provide better strength; the hybrid composite combines these properties. [Q5126]
• Silane is used to bond the filler to the resin matrix in composite dental fillings, enhancing the material’s mechanical properties. [Q5718]
• Bevelling cavity edges increases the surface area for bonding composite fillings, improving the adhesion and stability of the restoration. [Q5721]

Denture Materials

• Wrought stainless steel clasps can engage the deepest undercuts in removable partial dentures, providing strong retention. [Q0302]
• Silicone is more elastic and better at absorbing shock than acrylic, making it a superior material for denture bases in terms of comfort. [Q3654]

Endodontic Materials

• EDTA is a chelating agent used in endodontics to remove the smear layer and enhance canal cleaning. [Q5486]
• Formocresol solution is commonly used as a pulpotomy medicament, providing antibacterial properties and preserving pulpal tissue. [Q5607]
• Gutta-percha points are primarily made of gutta-percha, a plant-derived latex used for filling root canals. [Q5636]
• Super EBA is an endodontic sealer used for root canal therapy, providing a strong seal and preventing bacterial leakage. [Q5739]

Metal Restorations

• Class IV gold cannot be polished or burnished properly, making it unsuitable as a filling material. [Q0347]
• Proper condensation is critical in direct gold restorations for optimal results, ensuring a dense and durable filling. [Q0716]
• Copper elements were frequently used in the past for temporary restorations, providing a quick and effective solution. [Q3523]
• Gold can be polished to a high shine and smoothness, making it an excellent material for restorations with aesthetic requirements. [Q5988]

Polymerization and Curing

• Self-cured resin contains approximately 0.05 un-polymerized monomer, which can affect the material’s properties. [Q0143]
• Methyl methacrylate monomer exhibits about 0.21 volume shrinkage upon polymerization, affecting the fit and stability of the restoration. [Q0144]
• Light-cured composites tend to shrink more rapidly during setting, requiring careful management to minimize shrinkage stress. [Q0258]
• The powder in denture resins is referred to as polymer, which is mixed with liquid monomer to form a plastic dough. [Q0298]
• Insufficient pressure during flasking can cause porosity in acrylic dentures due to trapped air or inadequate compaction. [Q0460]
• Self-polymerizing acrylic resins have a higher content of residual monomers compared to heat-cured resins, which can affect biocompatibility. [Q0528]
• Gaseous porosity in full dentures, especially in thick areas, is caused by the release of gas during polymerization. [Q0643]
• Porosity on the internal portion of the resin is a common effect of excessive heat during the curing process. [Q0711]
• Benzoyl peroxide is used as an initiator in the polymerization process of self-cure acrylic resins, starting the curing reaction. [Q0739]
• Acrylic resin restorations are less commonly used due to significant shrinkage after polymerization, which can affect fit and function. [Q3155]
• Chemical composites typically have higher porosity than light-cured composites, impacting their mechanical properties. [Q4641]
• Composite polymerization shrinkage is typically 4-5%, requiring careful management to minimize the effects on the restoration. [Q5697]

Restorative Materials

• IRM stands for Intermediate Restorative Material, used for temporary restorations to provide a short-term solution. [Q5629]

Tooth Shade

• The gingival part of a tooth has a dentine background, giving it a different color compared to the incisal part, which is more translucent. [Q0690]

Casting and Prosthodontics

• The setting expansion of casting investment is approximately 0.1% to 0.5%, ensuring a precise fit for dental restorations. [Q0141]
• Gold alloys typically contract by about 0.014 during solidification, which must be accounted for in casting procedures. [Q0142]
• Type III hard alloys are suitable for bridges due to their strength and durability, making them ideal for prosthetic frameworks. [Q0161]
• Gypsum dies have weak edge strength and can lack surface detail, which can affect the accuracy of the final restoration. [Q0208]
• The gypsum-binder provides strength and rigidity to the investment material, ensuring a stable mold for casting. [Q0317]
• Type IV gold, which is 75% gold, is used for dental bridges due to its strength and durability. [Q0348]
• Casting gold in a hot mold compensates for the expansion of the investment material, ensuring a more accurate fit of the final restoration. [Q0462]
• Gaseous porosity is related to the presence of gases in the molten alloy, which can affect the quality of the casting. [Q0530]
• Die stones require less gauging water than dental plaster due to their denser nature, resulting in stronger casts. [Q0700]
• Using as little water as possible during mixing produces a harder surface on the cast, improving its durability. [Q0701]
• Immersion in saturated calcium sulfate solution causes negligible expansion, maintaining the accuracy of the cast. [Q0702]
• All the mentioned types of gold casting alloys are available, offering a range of options for different restorative needs. [Q0751]
• Flux is used during metal casting to protect the alloy from oxidation and to help distribute oxides evenly, ensuring a clean cast. [Q0782]
• Ductile alloys are commonly used for bridges due to their strength and ability to be shaped without breaking. [Q0907]
• Extra hard materials are typically used for the fabrication of Maryland bridges, providing the necessary strength and durability. [Q0908]
• The numbers represent the percentage of chromium (18%) and nickel (8%) in 18/8 wire, indicating its composition. [Q3008]
• According to the ADA classification, platinum and palladium are also considered noble metals used in alloys. [Q3151]

Dental Ceramics

• Lack of compression during the processing of porcelain can lead to porosity, resulting in a rough surface. [Q0155]
• Improper design or construction of the metal framework can cause failures in porcelain-fused-to-metal restorations. [Q0156]
• Firing porcelain in a vacuum reduces the size of air bubbles, decreasing porosity and improving the strength of the final product. [Q0529]
• Porcelain bonded to metal restorations are strongest in compression, resisting forces without fracturing. [Q0784]

Failures and Complications

• Rapid burnout of the investment can lead to cracking, compromising the quality of the cast. [Q0207]
• Using air as a cooler during cavity preparation can draw odontoblasts into the tubules, potentially causing hypersensitivity. [Q0520]
• Rapid wax burnout can cause the investment material to crack due to thermal shock. [Q0770]
• The lingual of lower molars is more prone to crack, indicating areas of stress concentration. [Q0823]
• An irregular shaped void on the surface of a gold cast indicates a fragment of investment was carried into the mould. [Q0828]
• Too much wax can cause fins in dentures during processing, affecting the fit and finish of the prosthesis. [Q3725]

Impression Materials

• Oil or water on impressions decreases the quality of the treatment cast, leading to inaccurate restorations. [Q0147]
• Polyvinyl siloxane impression materials are known for their dimensional stability and accuracy, making them the most stable choice. [Q0182]
• Wax patterns can distort if left on the bench for extended periods, affecting the accuracy of the final restoration. [Q0184]
• Vinyl polysiloxane is preferred for its dimensional stability over time, ensuring accurate impressions even after a delay. [Q0254]
• Perforation provides adequate retention for elastomeric impressions, ensuring they remain securely in place during the procedure. [Q0284]
• Alginate is the most flexible, followed by silicone, polysulfide, and zinc oxide eugenol, indicating their relative flexibility for different applications. [Q0297]
• Polyether impression materials are hydrophilic and can distort if kept in water, so they should not be kept in water within an hour. [Q0458]
• Polyether impression materials should be poured within 30 minutes after taking the impression to ensure accuracy and prevent distortion. [Q0465]
• Impression compounds should fuse above mouth temperature to maintain stability in the oral environment. [Q0703]
• A flow of 0.06% is acceptable for type I impression compound at oral temperature, ensuring appropriate viscosity and stability. [Q0704]
• Heating impression compound in a water bath can cause several issues including brittleness, graininess, and altered plasticity. [Q0705]
• The setting time of zinc oxide-eugenol impression pastes can vary significantly, affecting the final impression quality. [Q0706]
• Hydrocolloids used in dental impressions are of the emulsoid type, providing the necessary properties for accurate impressions. [Q0707]
• Elastomers are not water-loving and do not include potassium alginates, indicating their distinct properties compared to hydrocolloids. [Q0708]
• Polysulfide rubber impression materials are quite sensitive to temperature changes during curing, affecting their performance. [Q0709]
• The elastic properties of rubber impression materials can improve with time, ensuring better performance in dental applications. [Q0710]
• Polysulphide impression material requires a thin and dry layer of adhesive to ensure proper adhesion to the tray. [Q0735]
• Reversible hydrocolloids provide better detail and accuracy, especially in undercut areas, compared to alginate. [Q0737]
• Zinc oxide impression material can cause mucosal irritation in some patients, necessitating careful handling and application. [Q0818]
• Elasticity allows the impression material to return to its original shape after being deformed, preventing distortion when removing it from the mouth. [Q0876]
• Zinc oxide and eugenol impression paste is rigid and cannot be used in areas with significant undercuts as it may cause difficulty in removal and potential damage. [Q0930]
• Syneresis refers to the loss of water from a hydrocolloid impression material, leading to contraction and potential distortion of the impression. [Q0994]
• False, alginate impressions should be kept moist until the cast is poured to prevent distortion. [Q3199]
• Elastomers are a type of impression material that is flexible and used in dental applications. [Q3655]
• Addition silicone provides the most accurate detail reproduction, making it ideal for precise dental impressions. [Q5961]
• Addition silicone is used for custom-made posts due to its precision and stability. [Q5962]
• Polysulfide should be poured at least one hour after taking the impression to ensure accuracy and stability. [Q5963]
• Heat-curing silicone rubber provides superior mechanical properties, making it better suited for dental applications compared to cold-curing silicone. [Q5967]
• Agar is a reversible hydrocolloid impression material, known for its ability to be reused and provide detailed impressions. [Q6017]
• Zinc-oxide eugenol paste is ideal for obtaining a good impression for the resorbed lower ridge, providing accurate detail and stability. [Q6137]
• It is frequently used in spaced trays to obtain an impression, ensuring precise detail and accurate fit. [Q6138]

Material Science Innovations

• These are types of thermoplastics, thermosets, elastomers, biodegradable polymers, and fluoropolymers, each with unique properties and applications. [Q4635]
• Latex proteins in the gloves can chemically react with impression materials, preventing their setting and compromising the accuracy. [Q4636]
• Formaldehyde-containing sealants are considered toxic, requiring careful handling and application to avoid adverse effects. [Q5417]
• Diatek is a dental handpiece manufacturer, providing essential tools for dental procedures. [Q5484]
• Cermet is a composite material composed of ceramic and metal, offering a combination of properties from both materials. [Q5567]

Properties and Characteristics of Materials

• The modulus of elasticity is the measure of a material’s ability to deform elastically when a force is applied, expressed as the stress-strain ratio within the proportional limit. [Q0166]
• Both statements are true: gold clasps are more elastic, and Co-Chrome has a higher modulus of elasticity, indicating their different mechanical properties. [Q0188]
• Wrought metals are typically subjected to cold working processes, including annealing, to enhance their properties. [Q0213]
• The elastic limit is the minimum stress required to induce permanent deformation, indicating the material’s resistance to deformation. [Q0296]
• Strain is the deformation or displacement of material that results from an applied load, indicating its response to stress. [Q0526]
• Remnants of ameloblasts form the primary enamel cuticle, indicating the developmental process of enamel formation. [Q0546]
• Enamel rod prisms are generally perpendicular to the outer surface of the tooth, providing structural support and resistance to wear. [Q0720]
• The boiling point of acrylic is similar to that of water, indicating its thermal properties. [Q0783]
• Chroma refers to the saturation or intensity of the hue in shade matching, important for aesthetic restorations. [Q0836]
• Tungsten carbide is harder than porcelain, which is harder than enamel, followed by acrylic, indicating their relative hardness. [Q0844]
• A high noble alloy is defined by its high gold content, offering superior properties for dental restorations. [Q3080]
• Yes, aluminium polyacrylate is significantly stronger when used in glass ionomer, enhancing its mechanical properties. [Q3215]
• Pyrophosphate is an anticalculus agent found in toothpaste, preventing the formation of dental calculus. [Q3282]
• Chrome cobalt typically has a higher modulus of elasticity compared to gold, providing greater strength and rigidity. [Q3459]
• Cobalt chromium alloy is typically less flexible than stainless steel wrought wire, indicating their different mechanical properties. [Q3489]
• The corrosion index measures a material’s tendency to corrode, important for assessing the longevity of dental materials. [Q3528]
• Nickel titanium alloys exhibit shape memory properties, allowing them to return to their original shape after deformation. [Q3605]
• Yes, electrons are negatively charged, protons are positively charged, and neutrons are neutral, indicating their fundamental properties. [Q3658]
• The strength of amalgam depends on mixing time, particle size, setting time, and mercury ratio, indicating the factors affecting its properties. [Q4835]
• Streptococci are chains of cocci, not clusters, indicating their typical arrangement. [Q4836]
• Zinc acts as a scavenger in amalgam alloys by reacting with and removing impurities, enhancing its properties. [Q5524]
• Cementum is composed of hydroxyapatite, collagen, and water, indicating its structure and composition. [Q5576]
• Dentin is composed of hydroxyapatite, collagen, and water, providing its strength and resilience. [Q5577]
• Enamel is primarily composed of calcium, phosphorus, and fluoride in the form of hydroxyapatite crystals, indicating its composition. [Q5578]
• Glass ionomer cement is composed of glass particles and polyacrylic acid, providing its unique properties and applications. [Q5579]
• The depth of cure for composite resin is typically 2 mm, indicating the optimal thickness for effective polymerization. [Q5591]
• The minimum percentage of copper in modern dental amalgam is 0.3, enhancing its mechanical properties. [Q5653]
• Zinc acts as a scavenger in amalgam, reacting with and removing impurities to improve the alloy’s quality. [Q5923]
• Zinc causes corrosion in amalgam, necessitating careful handling and composition adjustments. [Q5924]
• Zinc causes black tattooing in amalgam restorations, indicating a potential side effect of its inclusion. [Q5925]

Safety and Handling

• Mercury vapor is dangerous because it can accumulate and cause brain poisoning. [Q0295]
• Triclosan is an antibacterial agent commonly found in toothpaste. [Q5543]
• The filter in a dental X-ray machine absorbs low-energy X-rays to reduce patient exposure. [Q5610]
• Impressions should be disinfected immediately to prevent cross-contamination. [Q5974]

Techniques and Procedures

• The reducing zone of the flame is used in melting gold to prevent oxidation of the metal. [Q0205]
• More blades and low speed result in less efficient cutting but a smoother surface finish when using carbide burs. [Q0263]
• Indirect wax techniques use wax that is hard at room temperature, making it easier to handle and carve. [Q0350]
• Burnishing helps eliminate excess mercury from amalgam restorations, improving their physical properties. [Q0771]
• 1.5mm is the minimal labial reduction needed to ensure sufficient space for the porcelain and metal structure of the crown. [Q0781]
• The range for the visible light cure beam is 470 nm or 450-500 nm. [Q0807]
• Using a cold glass slab slows the chemical reaction, extending the setting time of phosphate cements. [Q0849]
• The primary advantage of high-speed rotors is that they reduce vibration, providing a more comfortable experience for the patient. [Q0872]
• Investing the wax pattern promptly minimizes distortion, ensuring the accuracy of the final restoration. [Q0995]
• The primary distinguishing feature of roots forceps in a photo would be the type of extraction forceps. [Q3112]
• Good knowledge of all listed factors (tooth numbering system, extraction technique, forceps design, and tooth anatomy) is necessary. [Q3113]
• Acid etching dentin should typically be done for 20 seconds. [Q3749]
• Enamel should be acid etched for 30 seconds. [Q3750]
• Light-cured composites use a visible blue light with a wavelength of 400-450 nm to initiate polymerization. [Q5076]
• Type III etching refers to both enamel and dentin etching. [Q5384]
• Phosphoric acid is commonly used for acid etching in dentistry. [Q5736]
• Wet bonding involves applying adhesive to a moist tooth surface to enhance the bonding strength. [Q5756]
• The gingival wall is typically beveled in class II amalgam restorations to ensure proper adaptation and sealing of the restoration. [Q5813]