final

  1. What is the study of dental materials? The science of the properties, manipulation, and application of materials used in dentistry.

  2. Until 1970, the only allied oral health practitioner permitted to perform intraoral functions was the? Dental hygienist.

  3. Dental materials are classified as ____________, ____________, and ____________ materials. Preventive, restorative, and auxiliary (or adjunctive) materials.

  4. What characteristics should the perfect dental material possess? Biocompatible; durable and strong; esthetic (matches natural teeth); easy to manipulate; stable in oral environment; resistant to wear, corrosion, and fracture.

  5. Define evidence-based decision making. The practice of making clinical decisions based on the best available scientific research, clinical expertise, and patient preferences.

  6. Who is considered the “father of modern dentistry”? Pierre Fauchard.

  7. The disagreement over the value and safety of amalgam came to be called the? Amalgam controversy.

  8. The Goodyear brothers formulated a patent for ____________, a rubber used for denture base material. Vulcanized rubber (vulcanite).

  9. In 659 A.D. the ____________ first mentioned silver paste. Chinese.

  10. Who is credited for the development of an acceptable amalgam formula? G.V. Black (Greene Vardiman Black).

  11. Who is responsible for noting dental fluorosis in Colorado Springs? Dr. Frederick McKay.

  12. What association is responsible for establishing guidelines for testing products? American Dental Association (ADA).

  13. What agency is responsible to ensure that products meet standards of safety and efficiency and for the regulation over dental devices? U.S. Food and Drug Administration (FDA).

  14. Dental materials are not subject to control and regulation by the FDA. False.

  15. Name the two international agencies that develop specifications and testing on dental products. ISO (International Organization for Standardization) and FDI (World Dental Federation).

  16. The agency that awards the Seal of Acceptance to dental products is? American Dental Association (ADA).

  17. When was the earliest mention of restorative dentistry? Around 7000 B.C.

  18. The process concerning the American Dental Association Seal (ADA) requires how long for completion? Approximately 9–12 months.

  19. What restorative technique was introduced in 1955 along with synthetic resins? Composite resin restorations.

  20. A glue-like material composed of two or more substances in which one substance is suspended within another substance rather than go into the solution? Suspension

  21. What irreversible hydrocolloid is the most used impression material in the dental office? Alginate

  22. Which agar impression material can be heated to change from a gel to a fluid state? Reversible hydrocolloid

  23. Which alginate impression material is mixed to a sol state and converts to a gel as it sets? Irreversible hydrocolloid

  24. What is a hydrocolloid? A water-based material that forms a gel when cooled or chemically set.

  25. A maxillary alginate impression tray should extend to include the hamular notch and the tuberosities.

  26. How should mixed alginate be loaded into the impression tray? Uniformly and completely, starting from the posterior and moving anteriorly, avoiding air bubbles.

  27. An alginate impression should be poured within 10–15 minutes.

  28. Why should containers of alginate be turned end-over-end a few times before use? To evenly distribute the powder and prevent settling or clumping.

  29. The completed impression forms a negative reproduction of the teeth and tissues. The replica or model forms a positive replica of the teeth and tissues.

  30. Define hysteresis. The property of reversible hydrocolloids to change from a gel to a sol on heating and back to a gel on cooling.

  31. When mixing alginate, if the water temperature is increased, the working time is shortened.

  32. When should impressions be disinfected? Immediately after removal from the mouth.

  33. Impression trays that are pre-manufactured, supplied in a variety of sizes for both adults and children, can be metal or plastic, solid or perforated are referred to as stock trays.

  34. Some moisture will be lost from an alginate hydrocolloid impression even in 100% humidity. True

  35. One of the common uses of alginate impressions is for the fabrication of diagnostic casts. True

  36. Diagnostic casts can also be referred to as study models.

  37. What type of tray is a u-shaped, plastic frame with a fiber mesh stretched between the frame? Edentulous tray (or custom mesh tray)

  38. Agar is derived from an extract of seaweed called Gelidium.

  39. Name the ingredient in alginate that is added to cancel out the retardant effect of borax and agar. Potassium sulfate

  40. _______________ is the time from the start of mixing a material to seating it in the mouth. Working time

  41. Setting time can be lengthened by using cold water or shortened by using warm water.

  42. How long should an alginate impression be left in the mouth? 1–2 minutes, depending on brand and setting time

  43. When mixing alginate, the powder is added to the water.

  44. How should an alginate impression be stored if it cannot be poured immediately? Wrap in a damp paper towel and place in a sealed plastic bag to prevent distortion.

  45. Name the two contributory factors that will compromise the tear strength of alginate. Undercutting and rapid removal from mouth

  46. An impression of the occlusal relationship of opposing teeth in centric occlusion is known as a bite registration.

  47. What is a gel? A semi-solid material in which a liquid is dispersed in a solid network.

  48. Give an example of a gel. Alginate impression material

  49. The act of an impression absorbing moisture is called imbibition.

  50. The replica of a single prepared tooth that is used for fabrication of a restoration in a dental laboratory is called a die.

  51. Why should an alginate impression be removed from the mouth with a rapid “snap”? To prevent distortion and tearing of the material.

  52. A glue-like material composed of two or more substances in which one substance is suspended within another substance rather than go into the solution? Suspension

  53. What irreversible hydrocolloid is the most used impression material in the dental office? Alginate

  54. Which agar impression material can be heated to change from a gel to a fluid state? Reversible hydrocolloid

  55. Which alginate impression material is mixed to a sol state and converts to a gel as it sets? Irreversible hydrocolloid

  56. What is a hydrocolloid? A water-based material that forms a gel when cooled or chemically set.

  57. A maxillary alginate impression tray should extend to include the hamular notch and the tuberosities.

  58. How should mixed alginate be loaded into the impression tray? Uniformly and completely, starting from the posterior and moving anteriorly, avoiding air bubbles.

  59. An alginate impression should be poured within 10–15 minutes.

  60. Why should containers of alginate be turned end-over-end a few times before use? To evenly distribute the powder and prevent settling or clumping.

  61. The completed impression forms a negative reproduction of the teeth and tissues. The replica or model forms a positive replica of the teeth and tissues.

  62. Define hysteresis. The property of reversible hydrocolloids to change from a gel to a sol on heating and back to a gel on cooling.

  63. When mixing alginate, if the water temperature is increased, the working time is shortened.

  64. When should impressions be disinfected? Immediately after removal from the mouth.

  65. Impression trays that are pre-manufactured, supplied in a variety of sizes for both adults and children, can be metal or plastic, solid or perforated are referred to as stock trays.

  66. Some moisture will be lost from an alginate hydrocolloid impression even in 100% humidity. True

  67. One of the common uses of alginate impressions is for the fabrication of diagnostic casts. True

  68. Diagnostic casts can also be referred to as study models.

  69. What type of tray is a u-shaped, plastic frame with a fiber mesh stretched between the frame? Edentulous tray (or custom mesh tray)

  70. Agar is derived from an extract of seaweed called Gelidium.

  71. Name the ingredient in alginate that is added to cancel out the retardant effect of borax and agar. Potassium sulfate

  72. Working time is the time from the start of mixing a material to seating it in the mouth.

  73. Setting time can be lengthened by using cold water or shortened by using warm water.

  74. How long should an alginate impression be left in the mouth? 1–2 minutes, depending on brand and setting time

  75. When mixing alginate, the powder is added to the water.

  76. How should an alginate impression be stored if it cannot be poured immediately? Wrap in a damp paper towel and place in a sealed plastic bag to prevent distortion.

  77. Name the two contributory factors that will compromise the tear strength of alginate. Undercutting and rapid removal from mouth

  78. An impression of the occlusal relationship of opposing teeth in centric occlusion is known as a bite registration.

  79. What is a gel? A semi-solid material in which a liquid is dispersed in a solid network.

  80. Give an example of a gel. Alginate impression material

  81. The act of an impression absorbing moisture is called imbibition.

  82. The replica of a single prepared tooth that is used for fabrication of a restoration in a dental laboratory is called a die.

  83. Why should an alginate impression be removed from the mouth with a rapid “snap”? To prevent distortion and tearing of the material.

  84. A glue-like material composed of two or more substances in which one substance is suspended within another substance rather than go into the solution? Suspension

  85. What irreversible hydrocolloid is the most used impression material in the dental office? Alginate

  86. Which agar impression material can be heated to change from a gel to a fluid state? Reversible hydrocolloid

  87. Which alginate impression material is mixed to a sol state and converts to a gel as it sets? Irreversible hydrocolloid

  88. What is a hydrocolloid? A water-based material that forms a gel when cooled or chemically set.

  89. A maxillary alginate impression tray should extend to include the hamular notch and the tuberosities.

  90. How should mixed alginate be loaded into the impression tray? Uniformly and completely, starting from the posterior and moving anteriorly, avoiding air bubbles.

  91. An alginate impression should be poured within 10–15 minutes.

  92. Why should containers of alginate be turned end-over-end a few times before use? To evenly distribute the powder and prevent settling or clumping.

  93. The completed impression forms a negative reproduction of the teeth and tissues. The replica or model forms a positive replica of the teeth and tissues.

  94. Define hysteresis. The property of reversible hydrocolloids to change from a gel to a sol on heating and back to a gel on cooling.

  95. When mixing alginate, if the water temperature is increased, the working time is shortened.

  96. When should impressions be disinfected? Immediately after removal from the mouth.

  97. Impression trays that are pre-manufactured, supplied in a variety of sizes for both adults and children, can be metal or plastic, solid or perforated are referred to as stock trays.

  98. Some moisture will be lost from an alginate hydrocolloid impression even in 100% humidity. True

  99. One of the common uses of alginate impressions is for the fabrication of diagnostic casts. True

  100. Diagnostic casts can also be referred to as study models.

  101. What type of tray is a u-shaped, plastic frame with a fiber mesh stretched between the frame? Edentulous tray (or custom mesh tray)

  102. Agar is derived from an extract of seaweed called Gelidium.

  103. Name the ingredient in alginate that is added to cancel out the retardant effect of borax and agar. Potassium sulfate

  104. Working time is the time from the start of mixing a material to seating it in the mouth.

  105. Setting time can be lengthened by using cold water or shortened by using warm water.

  106. How long should an alginate impression be left in the mouth? 1–2 minutes, depending on brand and setting time

  107. When mixing alginate, the powder is added to the water.

  108. How should an alginate impression be stored if it cannot be poured immediately? Wrap in a damp paper towel and place in a sealed plastic bag to prevent distortion.

  109. Name the two contributory factors that will compromise the tear strength of alginate. Undercutting and rapid removal from mouth

  110. An impression of the occlusal relationship of opposing teeth in centric occlusion is known as a bite registration.

  111. What is a gel? A semi-solid material in which a liquid is dispersed in a solid network.

  112. Give an example of a gel. Alginate impression material

  113. The act of an impression absorbing moisture is called imbibition.

  114. The replica of a single prepared tooth that is used for fabrication of a restoration in a dental laboratory is called a die.

  115. Why should an alginate impression be removed from the mouth with a rapid “snap”? To prevent distortion and tearing of the material.

  116. What is the purpose of a sealant? To prevent pit and fissure caries by forming a protective barrier over the enamel.

  117. List the criteria that should be considered before sealant placement.
    A. Tooth must be fully erupted
    B. No existing decay on the tooth
    C. Pits and fissures are deep and retentive
    D. Tooth must be clean and dry
    E. Patient’s caries risk
    F. Ability to maintain isolation during placement

  118. Which teeth are the most susceptible to pit and fissure caries? Permanent molars, especially first and second molars

  119. Sealants are placed in permanent teeth only.
    B. False

  120. Chemically, sealants are similar to resin composites.

  121. List the methods of sealant polymerization.
    A. Self-cured (chemical-cured)
    B. Light-cured (photo-initiated)

  122. ___________ is a condition that results in consumption of excess fluoride during teeth formation. Dental fluorosis

  123. What is the acceptable optimal level of fluoride in drinking water? 0.7 ppm (parts per million)

  124. What is demineralization? The loss of mineral content from the tooth enamel due to acids produced by bacteria or other sources.

  125. How does erosion differ from caries? Erosion is the chemical loss of tooth structure from acids not involving bacteria, whereas caries involves bacterial acid attack.

  126. Fluoride’s greatest anti-caries benefit is gained from topical fluoride exposure after the teeth have erupted.
    A. True

  127. At what pH does tooth mineral dissolve? Below 5.5

  128. What is normal pH? Approximately 7 (neutral)

  129. A prescription is needed for chlorhexidine gluconate mouth rinse.
    A. True

  130. List the common mouth rinses containing chlorhexidine.
    A. Peridex
    B. Periogard
    C. Corsodyl

  131. Why is APF used most often in children? Because it is effective, easy to apply, and safe for developing teeth.

  132. Fluoride application benefits only children.
    B. False

  133. The etchant for sealants contains 35–37% phosphoric acid.

  134. Why is it necessary to etch a tooth before sealant placement? Etching creates microporosities in the enamel that allow the sealant to mechanically bond.

  135. Which teeth most frequently lose sealants? Why? Mandibular molars, due to occlusal forces and difficulty in maintaining isolation.

  136. ___________ or UDMA is a dimethacrylate monomer that is the resin component of sealants. Bis-GMA

  137. List the steps in sealant placement.
    A. Clean the tooth surface
    B. Isolate the tooth
    C. Etch the enamel
    D. Rinse the etchant
    E. Dry the tooth thoroughly
    F. Apply the sealant
    G. Cure the sealant
    H. Check for voids or bubbles
    I. Check occlusion and adjust if necessary

  138. What is the main reason for sealant failure? Moisture contamination during placement

  139. Define substantivity. The ability of a material to adhere to the tooth surface and continue to release active agents over time.

  140. Baseplate wax

  141. ______________ wax is used to adhere components together temporarily during fabrication and repair.
    Sticky wax

  142. ______________ range is when waxes will begin to soften and flow.
    Melting range

  143. ______________ wax is used for the base portion of a gypsum model.
    Boxing wax

  144. ______________ wax is used for a direct wax technique.
    Inlay wax

  145. ______________ provide a better fit into the vestibule of the impression material and cover sharp brackets and wires for ortho patients.
    Utility wax strips (periphery wax)

  146. ______________ wax is also called utility wax.
    Periphery wax

  147. ______________ wax is used to construct the metal framework of partial and complete dentures.
    Casting wax

  148. ______________ of wax goes down as the temperature of the wax goes up.
    Viscosity

  149. ______________ wax is used to produce wax occlusal registration for model articulation.
    Bite-registration wax

  150. ______________ wax is used within another impression material to correct undercut areas.
    Corrective wax (or undercut blockout wax)

  151. ______________ wax is used to produce the patterns for metal casting using the lost wax casting technique.
    Inlay wax (pattern wax)

  152. This method was invented for casting gold for dental restorations.
    Lost-wax casting technique

  153. Name the three classifications of waxes.
    Pattern waxes
    Processing waxes
    Impression waxes

  154. Waxes used directly in the mouth are Type ___________. Give an example.
    impression wax or bite-registration wax

  155. To avoid distortion, waxes should be stored ___________________.
    At or slightly below room temperature and away from heat sources

  157. The breakdown of a metal caused by a chemical or electrochemical reaction is corrosion.

  158. Name and describe the three types of amalgam alloy particles.
    A. Lathe-cut particles – irregular, formed by milling a cooled ingot
    B. Spherical particles – smooth, formed by spraying molten alloy into droplets
    C. Admixed particles – combination of lathe-cut and spherical

  159. A/An ____________ is a mixture of two or more metals.
    Alloy

  160. Name the metals that are found in dental amalgam.
    Silver, tin, copper, and mercury (plus small amounts of zinc in some alloys)

  161. Oxidation affecting a thin layer of a metal at its surface and does not change the metal’s mechanical properties is tarnish.

  162. Name and describe the three phases of the chemical reaction of alloy and mercury.
    A. Gamma (γ) phase – silver–tin alloy; strongest, original alloy
    B. Gamma-1 (γ1) phase – silver–mercury; strong matrix phase
    C. Gamma-2 (γ2) phase – tin–mercury; weakest, most corrosive

  163. Which is the strongest and least corrosive stage?
    Gamma (γ)

  164. Which is the weak and most corrosive phase?
    Gamma-2 (γ2)

  165. What metal inhibits corrosion in amalgam?
    Copper

  166. The gradual change in shape of an amalgam restoration due to compression of occlusion is creep.

  167. The mechanical device used to mix a silver-based alloy with mercury to produce amalgam is a triturator or amalgamator.

  168. Spherical amalgams have ____________ resistance to condensation pressures and require the use of ____________ condensers.
    Lower; larger-diameter

  169. Properly triturated alloy has a ____________ appearance.
    Shiny, cohesive, smooth

  170. Why is it necessary to check the occlusion after amalgam placement?
    To prevent high spots that cause fracture, postoperative pain, or accelerated wear

  171. How should finishing and polishing of an amalgam be done?
    Under water and using a light, intermittent touch

  172. Which alloys require less mercury to wet the particles?
    Spherical alloys

  173. What polishing agents can be used to polish amalgams?
    Tin oxide, pumice, and abrasive rubber polishing points

  174. High copper amalgams do not have a gamma-2 phase.
    True

  175. Bonding an amalgam during placement of a restoration seals the margins and reduces microleakage.
    True

  176. Carpets and tiled floors with seams trap amalgam and mercury.
    True

  177. How should amalgam scrap be stored?
    In a tightly sealed, airtight unbreakable container submerged in used x-ray fixer or glycerin

  178. When does amalgamation occur?
    When mercury dissolves the alloy particles during trituration

  179. What is a triturator?
    A mechanical device that mixes alloy and mercury by shaking at high speed

  180. Describe an under-triturated amalgam.
    Dry, crumbly, dull, lacks cohesiveness, difficult to condense

  181. A patient should ideally wait at least ____________ to chew on a newly placed amalgam.
    24 hours

  182. Spherical alloys require less mercury and set ____________ than lathe-cut.
    Faster

  183. Composite resins are composed of an organic resin matrix and inorganic filler particles joined together by a silane coupling agent.

  184. What are the fillers used in composite resins called? glass or quartz particles

  185. What is the activator in the catalyst of a chemically cured composite resin? tertiary amine

  186. The increment size for light-cured composites should be no thicker than 2 mm.

  187. Why are flowable composites useful as liners in large cavity preparations?
    They adapt well to internal surfaces
    They seal small voids and irregularities
    They improve stress distribution under heavier composite layers

  188. Packable composites are used to restore posterior teeth in areas of high function.
    A. True

  189. Recent research indicates that the composite resin material does not shrink toward the light.
    A. True

  190. In composite materials, the greater the filler content the lower the coefficient of thermal expansion and the greater the resin content, the greater the coefficient of thermal expansion.

  191. What part of the tooth is closest to dentin in color? body (middle third)

  192. What two criteria must be met for incremental addition of composite to bond to the previous layer?
    uncured oxygen-inhibited layer present
    surface free of contamination

  193. Why should composite material be stored in the refrigerator?
    To prolong shelf life
    To slow premature polymerization

  194. What is the most popular curing light? LED

  195. What chemical is used to prepare the dentinal tooth surface for placement of glass ionomer cement? polyacrylic acid

  196. Name three uses of glass ionomers.

  197. Class V restorations

  198. Liners/bases

  199. Cement for crowns/bridges

  200. Some composite resin materials give off heat when cured. This is a/an exothermic reaction.

  201. Why should composite resins be placed in small increments?
    To reduce polymerization shrinkage
    To ensure complete curing throughout each layer

  202. Macrofilled composite resins would not be used in non-stress-bearing areas.
    B. False

  203. Glass ionomers release fluoride.
    A. True

  204. List three ways that color is matched to the patient’s existing tooth structure.

  205. Use natural daylight or color-corrected light

  206. Moisten teeth before shade selection

  207. Select shade prior to tooth dehydration

  208. The use of two different materials in the same restoration is referred to as the sandwich technique.

  209. Matching

  210. 22. Microfilled composite
    Composite that contains very small filler particles averaging 0.04 mm in diameter.

  211. 23. Flowable composite
    A light-cured, low-viscosity composite resin that may be lightly filled.

  212. 24. Hybrid composite
    Composite that contains both macrofill and microfill particles.

  213. 25. Macrofilled composite
    First-generation composite resins that contain filler particles ranging from 10 to 100 mm in diameter.

  214. 26. Packable composite
    Highly viscous microhybrids that contain a high volume of filler..

  215. List three different types of composites and describe how they polymerize.

  216. Self-cured (chemically cured): polymerizes via a chemical reaction between base and catalyst

  217. Light-cured: polymerizes when exposed to blue LED light

  218. Dual-cured: begins with light activation and continues with chemical curing in deeper areas

  219. ____________ are the cells in the pulp that form dentin.
    Odontoblasts

  220. List common causes of tooth sensitivity.
    A. Exposed dentin
    B. Recession
    C. Tooth whitening/bleaching
    D. Abrasion or erosion
    E. Cracked teeth
    F. Recent dental procedures

  221. ____________ depolarizes the nerve so it cannot fire and cause pain.
    Potassium nitrate

  222. List the three basic types of sports mouth guards.
    A. Stock (pre-made)
    B. Boil-and-bite
    C. Custom-made

  223. Sports guards protect the teeth only.
    B. False

  224. What is the desirable thickness of a sports guard worn for heavy-contact sports?
    4 mm

  225. When a night guard is worn for treatment of TMJ dysfunction, it is referred to as a ____________.
    Stabilization splint

  226. A guard should soaked in denture cleaner.
    B. False
    (They should be cleaned with mild soap and water, not harsh denture cleaners that can damage material.)

  227. Only vital teeth can be bleached.
    B. False
    (Non-vital teeth can be bleached internally.)

  228. In-office bleaching produces the same results as home bleaching but is faster.
    A. True

  229. Tea, coffee, red wine, cola, grape juice, and berries contribute to the formation of ____________________.
    Extrinsic stains

  230. ____________________ stains are easier to bleach than _________________ stains.
    Extrinsic, intrinsic

  231. ____________________ is the use of a strong whitening agent activated by high-intensity light.
    Power bleaching

  232. The chemical used in home bleaching is _________________________.
    Carbamide peroxide

  233. List the over-the-counter (OTC) bleaching products.
    A. Strips
    B. Paint-on gels
    C. Trays

  234. Bleaching strips deliver ____________ peroxide gel.
    Hydrogen

  235. What is the main purpose of most desensitizing agents?
    To block tubules or prevent nerve depolarization

  236. List the members of the dental team that can fabricate a mouth guard prescribed by the dentist.
    Dentist
    Dental hygienist
    Dental assistant (with training depending on state law)

  237. What is the main purpose of a mouth guard?
    To protect the teeth and soft tissues from injury

  238. Can teeth bleaching cause the teeth to be sensitive?
    Yes

  239. Addition Silicone – The impression material that requires utilization of vinyl gloves.

  240. Polyether – The most hydrophilic elastomer.

  241. Addition Silicone – The impression material that has the smallest dimensional change on setting.

  242. Polysulfides – The impression material that has the ability to tolerate moisture around the preparation.

  243. Addition Silicone – Also used as bite registration materials because of their accuracy, dimensional stability, and ease of use.

  244. Condensation Silicone – This impression material requires to be poured immediately to prevent hydrogen formation.

  245. Addition Silicone – This impression material has the best dimensional stability and accuracy.

  246. Condensation Silicone – The impression material that was developed as an alternative to polysulfide due to ease of mixing, pleasant taste, and lack of odor.

  247. Addition Silicone – The most popular impression material for crown and bridge procedures.

  248. Polysulfides – The catalyst of this impression material may cause skin irritation.

  249. Addition silicone material in an automatic mixing cartridge system is utilized to make dies for crowns and bridges.

  250. What is the timeframe for pouring a polyether impression?
    Within 60 minutes (1 hour)

  251. How long should casts set before disinfecting?
    At least 30 minutes

  252. Should the hamular notch be blocked out with utility wax prior to taking an impression?
    Yes

  253. Addition silicone has greater dimensional stability and accuracy than condensation silicone.
    True

  254. What are the main advantages of the combination of porcelain and metal for fixed crown and bridge prosthodontics?
    Strength of metal with esthetics of porcelain; durability, resistance to fracture, and good marginal fit

  255. The metals that are used as the core for the porcelain-fused-to-metal (PFM) crowns are alloys of specific metals that will form a (an) ____________ layer as the metal is heated.
    Oxide

  256. What is the first layer of porcelain applied to the metal during fabrication of porcelain-metal restorations known as?
    Opaque porcelain

  257. The best arrangement for the coefficient of thermal expansion of the porcelain and the metal to be compatible is for the porcelain to have ____________ thermal expansion than the metal.
    Slightly lower

  258. Computer-assisted machining for crown and bridge techniques does not require that dies be poured or a temporary made.
    True

  259. When should a shade of a tooth be taken?
    Before tooth preparation, under natural light, and before isolation with a rubber dam

  260. Shade tabs should be moistened and held adjacent to the teeth to be matched.
    True

  261. ____________ is the fusion of ceramic particles at their borders by heating them to the point of beginning to melt.
    Vitrification

  262. A CAD/CAM machined crown uses an optical scanner to ____________.
    Make the impressions (digital images)

  263. Noble dental casting alloys do not require any gold but must contain at least 25% noble metals by weight.
    True

  264. One of the noble metals used for dental casting alloys is platinum.
    True

  265. Chromium is a base metal with the highest incidence of allergic response.
    True

  266. ____________ is used when gold castings are soldered to remove surface oxides so the solder will flow freely and wet the alloy surfaces as it melts.
    Flux

  267. Which metal is added to gold and silver solders to lower the melting range?
    Tin

  268. What are silver-based solders primarily used for in dentistry?
    Joining metal frameworks or attachments, such as in partial dentures and orthodontic appliances

  269. What is dental wrought wire primarily used for in dentistry?
    Orthodontic appliances, ligatures, and clasps

  270. Why would zinc be added to a base-metal mixture?
    Reduces oxidation when the alloy is cast

  271. Calculate the percentage of gold: 24 Karat =
    100% gold

  272. Calculate the percentage of gold: 12 Karat =
    50% gold

  273. Matching:

  274. Alloy composed of non-noble metals
    Base-metal alloy

  275. A solid compound made of two or more elements, one of which is a metal
    Alloy

  276. Alloy containing at least 60% noble metals, 40% of which must be gold
    High-noble metal

  277. Classification of metal based on its high cost
    Precious metal

  278. Alloy composed of metals that do not corrode readily; at least 25% must be noble metals
    Noble alloy

  279. A prepared tooth without occlusal/incisal and proximal contact may migrate laterally or occlusally/incisally within a few hours.

  280. What could result if the provisional restoration is too high?
    Occlusal trauma, discomfort, pain, and possible fracture of the provisional or opposing teeth

  281. What is the most durable of the pre-formed crowns?
    Stainless steel crown

  282. What are pre-formed celluloid forms and polymer crowns filled with?
    Acrylic resin

  283. What is the most common choice of template material for multi-unit and indirect provisional techniques?
    Vacuum-formed thermoplastic or silicone putty

  284. The primary disadvantage of the use of acrylic provisional materials is high shrinkage, acrylic odor and taste.
    True

  285. Utilizing acrylic materials in the fabrication of provisionals must be pumped on and off the preparation after initial polymerization. Explain why.
    To prevent heat buildup, reduce polymerization shrinkage, and ensure a proper fit on the prepared tooth

  286. Cement provisionals are most frequently fabricated with zinc oxide-eugenol or temporary cement.

  287. Zinc oxide provisionals should not be used if a permanent restoration is to be cemented with a resin luting agent.

  288. Denture adhesive can be used by the patient to replace a provisional crown if it comes off during a time when the dental office is closed.
    True

  289. Why is a well-adapted margin or finish line important on an extracoronal provisional restoration?
    To prevent microleakage, protect the pulp, maintain gingival health, and ensure proper fit for the final restoration

  290. Irritation, inflammation, and recession of the gingival tissue associated with a provisional restoration is caused by poorly adapted margins, overcontoured restorations, or improper hygiene.

  291. Provisional restorations are recommended for 2–3 months.
    True

  292. A provisional crown should share the forces of the adjacent and opposing teeth.
    True

  293. An inlay prep is an example of a procedure requiring an intracoronal provisional restoration.
    True

  294. Pre-formed crowns can be used for three-unit posterior bridge prep.
    False

  295. Where is the most common use of a stainless steel crown?
    Primary teeth or temporary coverage of posterior teeth

  296. Define the following:

  297. Intracoronal Restoration – A restoration that is placed within the confines of the tooth structure, such as an inlay or onlay.

  298. Extracoronal Restoration – A restoration that covers the external surface of a tooth, such as a crown.

  299. Indirect Fabrication – A method of making a restoration outside the mouth on a model or die, then placing it in the mouth.

  300. Direct Fabrication – A method of making a restoration directly in the mouth on the prepared tooth.

  301. Finish Line – The boundary or margin of a tooth preparation where the restoration meets the tooth structure.

  302. What polymerized acrylic resin is formed when a liquid monomer is mixed with a powder of small polymer beads?
    Polymethyl methacrylate (PMMA) acrylic resin

  303. What laboratory device helps keep the monomer from evaporating during polymerization and creates a denser acrylic?
    Pressure pot or curing unit

  304. List the stages of correct representation when acrylic powder and liquid are mixed together.

  305. Powder and liquid separate – dry powder, monomer liquid

  306. Wet sand stage – mixture appears sandy and granular

  307. Dough stage – pliable, cohesive mass, ready to mold

  308. Rubbery stage – elastic, sticky; near final setting

  309. What area on a heat-cured acrylic resin denture is polymerization shrinkage seen?
    Posterior palatal seal area and the intaglio (tissue-fitting) surface

  310. Plastic denture teeth do not wear the opposing natural or artificial teeth or restorations.
    A. True

  311. The specialty of dentistry that may include the fabrication of maxillofacial prostheses to replace facial tissues lost as the result of trauma, disease, surgery, or birth defect is:
    Prosthodontics / Maxillofacial prosthodontics

  312. List the correct sequence to prepare a broken denture for denture repair with chemical-cured acrylic repair material:

  313. Clean and disinfect the broken pieces

  314. Roughen the fractured surfaces

  315. Apply monomer to wet the surfaces

  316. Mix repair acrylic and apply to the fractured area

  317. Assemble pieces and hold in position

  318. Allow polymerization

  319. Finish and polish the repaired denture

  320. Why are record bases used?
    To support the wax rims and establish occlusal relationships, jaw relation records, and proper positioning of teeth for dentures

  321. Calculus can be removed by placing the prosthesis in a denture cleaning solution inside a zippered bag placed in an ultrasonic cleaner. True or False?
    True

  322. Why must dentures be relined periodically?
    To maintain a proper fit as the alveolar ridge and supporting tissues change over time, preventing looseness, irritation, and uneven pressure

  323. List the materials denture teeth are composed of.
    Porcelain, acrylic, composite

  324. Porcelain denture teeth are hard, esthetic, easily repaired and stain resistant.
    B. False – They are hard and stain resistant, but difficult to repair and may wear opposing teeth.

  325. Dentures may be soaked in mouthwash containing alcohol.
    B. False – Alcohol can dry and damage acrylic.

  326. List the advantages of proper brushing, polishing and cleaning of tooth structures and restorative materials.
    Removes plaque and stains, prevents decay and periodontal disease

  327. What scale ranks materials by their relative resistance to abrasion?
    Mohs hardness scale

  328. Porcelain is harder than enamel and dentin.
    A. True

  329. Large and irregular abrasive particles will cut more effectively.
    A. True

  330. How are fine particle diamonds supplied for polishing composites and porcelain?
    In pastes, discs, or strips

  331. The powder form of ____________ is used in sandblasting restorations in preparation for cementation and air abrasion.
    Aluminum oxide

  332. What is a major component of many prophylaxis pastes used to polish tooth structure, amalgam, and acrylic bases?
    Silex (silica) or pumice

  333. The philosophy of ____________ polishing is regarded as the most appropriate approach in the selection of which teeth and surfaces to polish.
    Selective polishing

  334. Margination may be indicated if the overhang is ____________, the contact is ____________, and there is no indication of caries.
    Small, accessible

  335. What material is recommended for polishing composite restorations?
    Aluminum oxide or diamond polishing pastes/discs

  336. Staining at the margins of composite restorations due to microleakage can be polished away.
    B. False

  337. How is biofilm removed from implants without abrading the surface of the titanium?

  338. Use of plastic, nylon, or titanium-coated instruments

  339. Ultrasonic scalers with plastic tips

  340. Non-abrasive air polishing with glycine powder

  341. Air polishing utilizes a combination of ____________, air, and water at a pressure of approximately 40 psi as an effective and efficient means of removing stains and soft deposits from enamel surfaces.
    Sodium bicarbonate

  342. What is the difference between prophylaxis toothpaste and over-the-counter toothpaste?
    Prophylaxis toothpaste is more abrasive and intended for professional cleaning; OTC toothpaste is less abrasive and safe for daily home use

  343. Rubber cup polishing does not remove the fluoride-rich layer of enamel.
    A. True

  344. The ADA Seal of Approval for dentifrices assures the consumer that
    The product is safe, effective, and has met ADA standards

  345. A natural abrasive composed of quartz and silica is
    Pumice

  346. A synthetic material that produces an extremely hard and efficient abrasive material is
    Diamond

  347. A synthetic abrasive, the powder form used in sandblasting restorations in preparation for cementation is
    Aluminum oxide

  348. Volcanic silica manufactured as a loose abrasive is
    Pumice

  349. ____________ is an extremely fine abrasive used extensively as a final polishing agent for enamel and restorations.
    Tripoli

  350. 22. Define the following:

  351. Finishing:
    The process of removing excess material, shaping, and smoothing restorations to create the desired form and contour

  352. Polishing:
    The process of creating a smooth, glossy surface by removing microscopic scratches and irregularities after finishing

  353. Cleansing:
    The process of removing debris, plaque, and stains from teeth and restorations to maintain oral health