Prostho-DentMat pre-boards exam PDF

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How does porcelain chemically bond to metal? a. Mixing of the metal atoms with the porcelain structure b. Mixing of oxidized metal layers with porcelain oxides c. Interposition of an intermediate metal layer d. Wetting of the porcelain onto the metal surface The process by which a casting is heated ...

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1. How does porcelain chemically bond to metal? a. Mixing of the metal atoms with the porcelain structure b. Mixing of oxidized metal layers with porcelain oxides c. Interposition of an intermediate metal layer d. Wetting of the porcelain onto the metal surface 2. The process by which a casting is heated in a porcelain furnace to a temperature of 980’C to burn off any remaining impurities prior to adding porcelain is called: a. Quenching b. Pickling c. Investing d. Degassing 3. Porcelain bonded to metal is strongest when a. Under compression b. Fired several times before completion c. Tempered after firing d. Air fired 4. All of the following are characteristics of ZOE impression paste except one. Which one is the exception? a. No shrinkage even if store for many days b. Dimensionally unstable c. Sets quickly d. Sets hard e. Excellent detailed reproduction 5. The property that most closely describes the ability of a cast gold inlay to be burnished is; a. Modulus of resilience b. Ultimate strength c. Modulus of elasticity d. Elastic limit e. Percentage elongation 6. The alginate mix is usable regardless of water temp as long as there is adequate working time. Changing water/powder ratio and the mixing time will alter the gelation time, but these methods also impair certain properties of the material. a. 1st false, 2nd true b. Both true c. 1st true, 2nd false d. Both false 7. Elongated grains in the microstructure of a wrought wire indicates that it has been; a. Hardened by heat treatment b. Stress relief annealed c. Cold worked d. Recrystallized 8. Which of the following impression material has the longest working time?

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a. Polyether b. Reversible hydrocolloid c. Polysulfide d. Polyvinyl siloxane Dental plaster and stone are vibrated after mixing to: a. Reduce setting time b. Minimize distortion c. Increase the setting time d. Eliminate air bubbles Dental plaster (type II) powder differs from dental stone (type IV) powder primarily in; a. Crystal structure b. Solubility in water c. Chemical formula d. Density Ceramics can mimic tooth ___ better than any other material. a. Esthetics b. Function c. Anatomy d. None of the above The residual sodium alginate has the nasty habit of readily giving up water which is called; a. Shrinkage b. Inhibition c. Expansion d. Syneresis In metal-ceramic crowns and FPD, the function of tin, indium and other readily oxidized minor components of the alloy is to; a. Improve bonding b. Improve thermal expansion matching between metal and porcelain c. React with the porcelain and make an opaque layer to mask the metal d. Decrease porosity When mixing alginate, the lower the temperature a. The shorter the gelation time b. Gelation time is not affected c. The longer the gelation time One advantage of dental porcelain restorations is: a. Poor esthetics b. Expansion c. Radioactivity d. Brittleness All gypsum products come from the mineral gypsum, which is the a. Dehydrate form of calcium sulfate b. Monohydrate form of calcium sulfate

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c. Hemihydrate form of calcium sulfate With which of the following impression materials is it advisable to wait 20 to 30 minutes before pouring of models for stress relaxation to occur? a. Condensation silicones b. Polysulfides c. Polyethers d. polyvinyl siloxanes low-fusing porcelain is usually used for the manufacture of: a. metal ceramic crowns b. all ceramic crowns c. denture teeth d. no answer provided Which of the following materials will produce the most rigid restoration for frameworks of the same dimension? a. Cobalt-chromium alloys b. Wrought gold c. Partial denture casting gold in the hardened condition d. Palladium alloys Dental stone and dental plaster both have a slightly different type of principal component (calcium sulfate hemihydrate) Dental plaster has: a. Gamma-hemihydrate and dental stone has beta-hemihydrate b. Beta-hemihydrate and dental stone has alpha-hemihydrate c. Alpha-hemihyrdate and dental stone has beta-hemihydrate When using which impression material can you delay pouring up the model for up to one week? a. Polyether b. Vinyl polysilicone c. Polysulfide d. Reversible hydrocolloid Which of the following syringe materials is the most rigid and, therefore, the most difficult to remove from the mouth? a. Condensation silicone b. Polyether c. Polysulfide d. Addition silicone e. Reversible hydrocolloid Which teeth should ideally provide the predominant guidance through the full range of movement in lateral mandibular excursions? a. 1st molars b. Incisors c. Canines d. Premolars

24. Which of the ff best explains why the dentist should provide a postpalatal sealin a complete maxillar denture? a. Tissue displacement b. Errors in fabrication c. Polymerization and cooling shrinkage d. Deformation of the impression material 25. The most likely tissue reaction to gross overextension of a complete denture that has been worn for a long time is: a. Epulis fissuratum b. Giant cell reparative granuloma c. Papillary hyperplasia d. Pyogenic granuloma 26. The incisal edges of the maxillary anterior teeth should just touch the wet/dry line of the lower lip when enunciating which sound(s). a. Linguoalveolar sounds or sibilhants (such as s,z,sc,and,ch) b. Fricatives or labiodental sounds (such as f,v,p) > b,p,m c. Linguodental sounds (such as this, that or those) 27. Where do the occlusal contact possibilities occur during a protrusive movement? a. On the maxillary distal inclines and mandibular distal inclines b. On the maxillary distal inclines and mandibular mesial inclines c. On the maxillary mesial inclines and mandibular mesial inclines 28. Which of the following materials available for recording centric relation when fabrictating a removable partial denture is the least satisfactory? a. Quick-setting impression plaster b. Metallic oxide bite registration plate c. Silicone impression materials d. Modeling plastic e. Wax 29. During non-working excursive movements, the permanent max 1 st molar’s mesiolingual cusp escapes through: a. The distobuccal groove on the mand 1st molar b. Lingual groove of the mandibular 1 st molar c. The MB groove of the mand 1st molar d. On the space bet the MB and DB cusps of the mand 1 st molar e. The buccal groove of the mandibular second molar 30. An edentulous px has slight undercuts on both tuberosities and also on the facial of the anterior maxilla. To construct a satisfactory maxillary complete denture, you should reuce which of the following? a. Both tuberosity undercuts b. The anterior undercut only c. All undercuts 31. All of the ff muscles are involved in elevating mandible (closing mouth) except:

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a. Lateral pterygoid muscles b. Master muscles c. Temporalis muscles d. Medial pterygoid muscle Which of the following is the most important reason for tx of hyperplastic tissue before construction of a complete or removable partial denture? a. It will make the face-bow transfer easier to perform b. The final impression material will flow better c. To provide a firm, stable base for the denture d. It will make the patient feel better Which of the following adverse conditions may arise if occlusal vertical dimension is increased? a. The opening muscles may become strained b. The closing muscles may become too relaxed c. Soreness may occur at the corners of the mouth. d. The closing muscles may become strained Which of the ff explains why mandibular molars should not be placed over the ascending area of the mandible? a. The occlusal forces over the inclined ramus would dislodge the mandibular denture. b. The teeth in this area would interfere with the action of the masseter muscle c. The teeth in this area would encroach on the tongue space d. The denture base ends where the ramus ascends e. The molars would interfere with the retromolar pad When the mandible is in its physiologic rest position, the distance between occluding surfaces of maxillary and mandibular teeth or occlusion rim is; a. Interocclusal distance b. Centric occlusion c. Vertical dimension of rest d. Vertical dimension In a complete maxillary denture, accurate adaptation of the border of the ax facial flange affects which of the ff the most? a. Speech b. Esthetics c. Stability d. Support Which of the ff jaw-relation records should be used for setting both the medial and superior condylar guides on an arcon articulator? a. Protrusive interocclusal records b. Lateral interocclusal records c. Centric relation d. Intercuspation In a complete denture px, when the teeth, occlusion rims and central bearing point are in contact and the mandible is in centric relation, the length of the face is known as the:

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a. Interocclusal rest space physiologic rest position b. Occlusal vertical dimension c. Vertical dimension rest vertical dimension Which of the ff statements concerning selective grinding in complete denture fabrication for centric relation are true? a. Ideally selectve grinding should result in harmonious cusp-fossa contacts of all upper and lower fossa (andmarginal ridges of bicuspids) b. Only grind cusp tips if they are premature in centric, lateral and protrusive movements c. Both true d. Both false When selecting shade, remove all distractions (e.g., lipstick, dark glasses, heavy make-up, etc). Quick rubber cup and paste prophylaxis can make shade selection more accurate a. 1st true 2nd false b. 1st false 2nd true c. Both true d. Both false Gingival electrosurgery involves the reduction of the ___ wall of the gingival sulcus (removal of a ___ layer of cervicular gingival tissue) a. Inner, thin b. Inner, thick c. Outer, thick d. Outer, thin When tx planning for fixed prostho, which of the ff info can be obtained by studying dx cast? a. The presence of ppockets b. The crown-to-root ration of potential abutment teeth c. Mesial/distal drifting rotation and faciolingual displacement of potential abutment teeth can be clearly seen d. Length of root of abutments Which luting agent (cement) has the lowest solubility? a. Zinc phosphate b. Glass ionomer c. Zinc polycarbonate d. Resin-modified glass ionomer The absolute max number of post teeth, which can be safely replaced with a fixed bridge a. 2 b. 4 c. 3 d. 1 The pontic design that leaves a space between pontiv and the ridge. This most commonly used where esthetics are not important(non-appearance zone, posterior mandible) a. Modified ridge-lap pontic design b. Saddle-ridge lap pontic design

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c. Sanitary (hygienic pontic design) The chamfer cervical finish: a. Greatly facilitates the adaptation of copper bands in making compound impressions b. Provides a well-defined finish line and adequate space in cervical region c. Requires building up the short mesial end of the crown d. Is the least conservative of the 3 types of cervical finish lines A porcelain JC will fracture when: a. Subjected to tensile forces by opposing teeth b. Used in an end-to end occlsion c. Fabricated for a mandibular incisor d. Subjectedto compressive forces by the opposing teeth e. Allowed to contact the opposing teeth in centric occlusion Margin design for metal ceramic with metal collars a. Shoulder with bevel or chamfer b. Bevel c. Shoulder d. None of the above The most important criterion for a gingival margin on a crown prep is that: a. It is a dull knife edge b. Its position be easily discernible c. Its position be subgingival d. Its position be supragingival When observing during shade selection, do not gaze for greater than ___ at a time. a. 5 sec b. 9 sec c. 8 sec d. 7 sec This component of the fixed bridge must provide patient comfort, convenient contours for hygiene, and be esthetic if indicated. a. Artificial tooth b. Pontic c. Abutment d. No anwer Metal ceramic crowns are rarely indicated for use on ___ teeth, and are not indicated at all for ___ teeth in a class III edge to edge relationship, where the occlusal forces can subject them to fracture. a. Ant, post b. Ant, ant c. Post, ant d. Post, post The shoulder cervical finish: a. Greatly facilitates the adaptation of copper bands in making compound impressions

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b. Requires building up the short mesial end of the crown c. Is the least conservative of the 3 types of cervical finish lines d. Provides a well-defined finish line and adequate space in cervical region The ideal crown-to-root ratio of a tooth to be utilized asa bridge abutment is: a. 2:1 b. 1:2 c. 1:1 d. 3:1 While doing shade selection, remember that ___fatigue accentuates ___ sensitivity. a. Orange, yellow b. Blue, yellow c. Green, red d. Blue, green Important point about gingival electrosurgery. Use ___ instruments (mirror, exploerer, etc) instead of ___ to prevent burning and tissue destruction of the surface contacted. a. Metal, plastic b. Plastic, metal c. Silver, copper The guidelines for usage of porcelain JC and all-ceramic crowns, such as tooth prep, are ___ critical and general ___complicated than for the metal-ceramic restorations. a. More, less b. Less, less c. Less, more d. More, more The __ is defined as the stress at which a material begins to deform to deform physically. a. Ductility b. Yield strength c. Yield point d. Hardness e. None of the above A post and core is preferred to a post crown for an abutment tooth because: a. Less chair time is required in its fabrication b. Better esthetics can be achieved c. It is stronger d. It can be treated as an independent abutment Half-closed eyes can increase the sensitivity of retinal rods to better choose the ___ of the color. a. Value b. Hue c. Chroma In constructing a fixed partial denture for a px, the dentist will use hygienic pontic. Which of the following will primarily determine the faciolingual dimension of the occlusal portion of this pontic?

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a. The width and crestal position of the edentulous ridge b. The position of the opposing contact areas c. The length of the pontic d. The masticatory force of the px Margin design for full gold crown a. Bevel (feather edge or chamfer) b. Shoulder c. Shoulder with bevel or chamfer d. None of the above The construction of a bridge is normally scheduled after the following is/are completed: a. operative dentistry b. surgery c. periodontal therapy d. surgery, periodontal therapy and operative dentistry a non-rigid connector is comprised of: a. keyway b. a key c. a key and a keyway a removable partial denture is preferred over a fixed one when: a. there is an uneven plane of occlusion with supraerupted or submerged teeth b. the needed abutments are malaligned c. there are bilateral edentulous areas d. the patient lack motivation or is incapable of cleaning a fixed bridge in designing tooth-borne removable partial dentures, where are the rest placed? a. Anywhere b. On the abutments next to the edentulous space c. Farthest possible from the edentulous space d. Rests can be omitted The patient complains of “looseness” with new bilateral distal extension RPD. This is probably caused by: a. Deflective occlusal contacts b. Insufficient facial overlap on post teeth c. Passive clasp pressure on abutment teeth d. Thin flanges on acryclic bases The relationship of denture base to bone that resists dislodgement of the denture in a horizontal direction is: a. Esthetics b. Stability c. Support d. Pressure Examination of the mounted diagnostic cast should help ascertain

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a. Evidence of premature contact, the presence of periodontal pockets and occlusal relationships b. The crown root ratio and the long axis relationship of proposed abutment teeth c. The long axis relationship of proposed abutment teeth, the amount of tooth reduction necessary to arrive at retentive prep and the compatible path of insertion d. The rel’tship of opposing teeth to abutment teeth and to the spaces, as well as the presence of periodontal pockets Major connectors of a maxillary partial denture may be beaded in order to: a. Produce a positive contact against tissue b. Form a finish line between metal and acrylic c. Produce a stronger framework d. Aid in the retention of the denture e. Retain the acrylic to the metal framework The most reliable method of recording centric occlusion when constructing a mandibular bilateral distal extension partial denture occluding with natural teeth is to construct a stabilized occlusion rim a. For the mandibular master cast and record the relationship with zinc oxide eugenol registration paste b. Attached to the finished partial denture frame and record the relationship with zinc oxide registration paste for the mandibular master cast and record the relationship with baseplate wax c. For the mandibular master cast and record the relationship with utility wax Which of the following design characteristics of a partial denture is most important to oral health: a. Bracing b. Support c. Retention d. Stability According to the rules of classifying edentulousspaces by Kennedy, which classification can never have a mod space? a. Class 4 b. Class 2 c. Class 1 d. Class 3 Which of the ff mechanical prop limits the amt ofadjustment of a base metal removable clasp arm? a. Tensile strength b. Hardness c. Stiffness d. Elongation Retention of the RPD should not be considered the prime objective of design. Instead efficacy esthetics, comfort and preservation of health are considered moreimportant.

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a. Both true b. 1st false, 2nd true c. 1st true, 2nd false d. Both false The cast-wrought combination clasp is desirable a. Because it offers no stress-breaking action b. Because it cannot be re-adapted c. Because of its ability to flex in all direction d. Only when used with extension base partial denture The most effective means of limiting applied loads to abutment teeth in distal extension partial denture is by a. Splinting abutments to adjacent teeth b. Maintaining a stable denture base tissue relationship c. Using stressbreaker d. Using acrylic replacement e. Using the abutment teeth without splinting Abutment teeth for RPD should be contoured so that the retentive clasp tips can be placed a. On the mid 3rd of the crown b. On the gingival 3rd of the crown c. In a mesial undercut d. In distal undercut Indirect retention is designed to a. Help resist tissueward movt of an extension base partial denture b. Engage an undercut area of an abutment tooth c. Help resist dislodgement of the free end base in an occlusal direction d. Stabilize tooth borne removable partial denture Most favorable clasp design for distal extension cases: a. Ring b. Circumferential c. RPI d. Bar A precision attachment removable partial denture is preferred when: a. Teeth are present on both ends of the edentulous areas b. No posterior abutment teeth are present c. Abutment teeth are well supported d. Abutment teeth require restoration e. The px is able to pay for the service In establishing the proper tilt of the surveyor table when surveying a cast, the dentist would 1 st: a. Adjust the tilt to permit the establishment of parallel bracing planes b. Locate undercuts with cast placed on a horizontal plane c. Use an arbitrary tilt to create undercuts d. Establish an anterior tilt for the maxillary cast and a posterior tilt for the mandibular cast

83. For an extension –base RPD which of the ff is the most important to maintain the remaining supporting tissues a. Using stress releasing clasps lim...