1. Periodontal objectives prior to restorative dentistry procedures are
a. Elimination of all diseased gingival attachments with the resultant crevicular depth as close to zero as possible
b. Elimination of all diseased root structure utilizing resection techniques
c. Elimination of all etiological factors responsible for periodontal disease
d. A and B
e. A and C
f. None of the above
Answer. D. B is incorrect because diseased root structure can be treated in other than resection techniques.
2. A modified ridge lap pontic
a. Is a sanitary pontic
b. Causes chronic inflammation
c. Is an all convex pontic except the occlusal surface
d. Should cfontact the ridge with pressure
e. Is difficult to maintain
Answer. C. A modified ridge lap pontic is all convex in design except for the occlusal surface. The ridge lap area on the lingual is removed enabling patients to maintain the infrapontic area.
3. A pontic should be what part of the facial lingual width of the tooth it replaces
a. Four-fifths
b. Seven-eigths
c. One-fifth
d. The same
e. Five-eighths
f. None of the above
Answer. D. A pontic which is smaller than the tooth it replaces will cause food impaction areas, resulting in trauma to the tissue. A pontic which is larger than the tooth it replaces will obliterate the embrasure area and cause both soft and hard tissue destruction.
4. Ridge lap pontics cause pressure atrophy of the residual ridge resulting in
a. Chronic inflammation of the ridge and papillae
b. Ulceration of the ridge tissue
c. Destruction of support of the abutment teeth
d. A and B
e. A and C
f. All of the above
Answer. F. Pressure athrophy caused ny ridge lap pontics will produce chronic ulcerative lesion of the ridge tissue which may spread to the proximal of the abutment teeth, resulting in destruction of both hard and soft tissue.
5. Restorative procedures following vestibular surgery should be delayed
a. Three weeks
b. One month
c. Three months
d. Five month
Answer. C. Restorative procedures should be postponed because of the creeping attachment theory; that is, the tissue will continue to migrate coronally during the healing process.
6. The primary reason for the delay is because of
a. The kinetic theory
b. Hypersensitivity
c. Creeping reattachment
d. The bleeding problems associated with performing restorative procedures
Answer. C. The “creeping re-attachment theory” states that tissue will continue to grow after the healing process in completed. Therefore, adequate time should be allowed before starting restorative procedures that involve the gingival marginal tissues.
7. The controlling factor to preserve adequate embrasure spaces in full coverage restoration is
a. Contacts placed at the occlusal third
b. Tooth preparation
c. Surgical removal of the papillary tissue
d. The elimination of veneering material on the proximal surfaces
Answer. B. Inadequate interproximal tooth preparation will result in blockage of the embrasure space with the restorative material, consequently causing a destruction of the papillary tissue in that area.
8. To prevent marginal inflammation, the most critical area in restoring contours on a tooth is the
a. Normal
b. Occlusal surface
c. Middle third
d. Gingival third
e. Lingual margin
Answer. C. The middle third of a tooth is the ares responsible for the deflection of food away from the marginal gingival; if this contours is neglected food will be directed into that area, causing marginal inflammation.
9. The tissue on the infrapontic surface of a pressure ridge lap pontic is usually
a. Normal
b. Painful
c. Chronically inflamed
d. Plaque free
e. Highly keratinized
Answer. C. The tissue in the infrapontic area of a ridge lap pontic is usually chronically inflamed because of the pressure from the restorative material. It is never painful and is usually full of plaque.
10. The treatment of choice for tilted teeth is
a. Extraction
b. Telescopic crowns
c. Full crowns
d. Orthodontics
e. Endodontics and full coverage
Amswer. D. The idea treatment for tilted teeth for a prosthetic device is orthodontics. Restorative procedures utilizing telescopic crowns or full coverage don’t effectively rid the area of food entrapment and plaque formation.
11. One primary advantage of polycarboxylate cements is that they
a. Are insoluble in oral fluids
b. Have very high compressive strength
c. Cause minimal pulp irritation
d. Have a long setting time
e. Are reliable inhibitors of secondary caries
Answer. C. The high pH of polycarboxylate cements results in minimal pulpal irritation.
12. A patient complains of a toothache triggered by heat and relieved by cold. The involved tooth is best treated by which of the following?
a. Cold application
b. Root canal theraphy
c. Pulpotomy
d. Corticosteroids
e. Antibiotics
Answer. B. A tooth triggered by heat indicates that a necrotic process is occurring in the pulpal chamber. The heat causes expansion of gases created by bacteria which in turn exerts pressure on the remaining vital tissue. Cold causes contraction of the gases resulting in a soothing effect. The theraphy of choice for a tooth that is necrotic is root canal theraphy.
13. The earliest apical radiographic change seen in a pulpally involved tooth is
a. Apical resorption
b. Thinning of the lamina dura
c. Thickening of the periodontal ligament space
d. Loss of lamina dura
e. Hypercementosis
Answer. C. Thickening of the periodontal membrane space in a pulpally involved tooth is the result of bacterial forming in the apical region and distending the periodontal ligament space.
14. The radiographic procedure of choice for use in periodontal examination is the
a. Paralleling technique
b. Bisecting technique
c. Bite-wing
d. Pantograph
e. Laminograph
Answer. A. paralleling technique or long cone technique gives a better represention of the bony architechture for diagnosis of periodontal diseased by elimination of elongation and foreshortening.
15. What is the role of pins in restoring a large amount of lost tooth structure in a molar tooth? They are
a. Used to reinforce the restorative material
b. Used to reduce the setting expansion of the amalgam
c. Used to retain the amalgam in the cavity preparation
d. Used only in teeth to be crowned
e. To be used only as temporary restoration
Answer. C. The grooves on the pins used for restoring a large amount of lost tooth structure are designed to retain amalgam in the cavity preparation.
16. Which of the following types of base materials must not be placed in contact with polymethyl methacrylate?
a. Zinc phosphate cement
b. Calcium hydroxide
c. Zinc oxide eugenol cements
d. Germicidal cements
Answer. C. Cements containing an essential oil such as eugenol will attach methyl methacrylate crowns and temporaries and inhibit the polymerization of the resin. The material will remain soft.
17. A patient returns to the office two days after a dentist has placed an MOD inlay in a maxillary premolar. The patient complains that the tooth is hypersensitive especially under chewing pressure. This indicates
a. Chemical irritation
b. Periodontal ligament involvement
c. Pulpal hyperemia
d. High coefficients of thermal conductivity
Answer. B. Periodontal ligament is involved because undue pressure is placed on that tissue when a restoration is high or in malocclusion. The resulting pressure from a high restoration is transmitted by the tooth to the periodontal ligament.
18. Cement bases wshould have which of the following characteristics?
a. High edge strength
b. Low coefficient of thermal expansion
c. Low coefficient of thermal conductivity
d. High ductility
e. Adhasiveness
Answer. C. The rationale behind the use of a base cement is to insulate the tooth; therefore one would expect to have a low coefficient of thermal conductivity.
19. Which of the following does not aid in retention of a two surface inlay?
a. Cavosurface bevel
b. Reverse bevel
c. Dovetail
d. Parallel walls
e. Sharp line angles
Answer. A. The primary function of the cavosurface bevel is to enable the operator to work the metal and close the margins. It is difficult to close a butt joining margin because of casting, investment and wax discrepancies.
20 . Of the following, the greatest disadvantage of precision intracoronal attachments when they are used in partial denture construction is that they
a. Present esthetic problems
b. Are unstable
c. Are costly
d. Require extensive preparation of the abutment teeth
Answer. D. To allow for the insertion of a female attachment more tooth structure should be removed from the abutment teeth, to accommodate the attachment. It is desirable that the attachment be entirely intracoronal in order to prepare normal tooth contours.
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