MULTIPLE CHOICE TEST
Manual of Dental Implants
BASIC PRINCIPLES
Question 1: Implants are most often made of: A. Titanium
B. Hydroxyapatite C. Stainless steel D. Gold alloy
Answer: A.
Implants are made of titanium, because bone cells attach to it easily. B is wrong because some implants are coated with hydroxyapatite, but the implant body is a titanium alloy. C and D are wrong, because stainless steel and gold alloy would not be favorable to osseointegration.
Question 2: The rough surface of implants is: A. Due to fabrication errors
B. Not desirable for osseointegration
C. Important to remove at the neck so that gingival plaque does not attach D. Desirable for improved osseointegration
Answer: D.
Bone cells react best to titanium surfaces that are rough, and, thus, roughening improves osseointegration. A is wrong because implant surfaces are smooth when fabricated, and roughness is purposely added. B is wrong because, although roughness is not necessary, it improves osseointegration. C is wrong because it is not possible to smooth a rough surface clinically. Most implants have a smooth collar to avoid increased plaque collection in the event that the neck becomes exposed to the oral cavity.
Question 3: Osseointegration means:
A. Full contact between bone and the implant body
B. Fibrous attachment to the implant C. 40% to 70% bone/implant contact
D. Clinical detection of a particularly stable implant
Answer: C.
An implant is considered osseointegrated when bone is attached to 40% to 70% of the implant surface. A is wrong because bone attachment to implants is never continuous. B is wrong because a fibrous attachment to an implant would mean failure. D is wrong because clinical detection of osseointegration does not distinguish quality of integration.
Question 4: The first event leading to osseointegration that occurs after implant placement is:
A. Growth of new bone cells B. Formation of a blood clot C. Growth of fibrous tissue D. Gingival downgrowth
Answer: B.
A blood clot forms between bone and the implant within the first few minutes. A is wrong because bone cells grow slowly and invade the implant surface at a much later date. C and D are wrong because growth of fibrous or soft tissue would not be replaced by bone and would result in failure.
Question 5: Excessive force on implant crowns results in: A. Trauma to bone
B. Immediate fracture of implant components
C. Fatigue of implant components, leading to fracture
D. No damage to implants because of their high resistance to force
Answer: C.
Excessive force leads to component fatigue, and, eventually, fracture. A is wrong because although there may be some damage to adjacent bone, the implant complex suffers most. B is wrong
because immediate fracture is unlikely. D is wrong because implants and their components are fragile.
Question 6: Preload is:
A. Placement of a screw without the application of adequate torque B. Pressure on a provisional crown
C. Tension placed by screws to protect implant components from displacing forces D. The force transmitted by the crown to the implant
Answer: C.
Preload is tension that prevents the movement of implant components, thereby protecting them from biting forces. A is wrong because preload requires adequate torque. B is wrong because the concept of limited force application on a provisional restoration is part of progressive loading. D is wrong because the transmission of force to an implant is not described by a particular term.
Question 7: Plaque and calculus: A. Do not attach on implants B. Attach loosely to implants
C. Have a different composition on implants D. Accumulate on implants similarly to teeth
Answer: D.
Plaque and calculus accumulate on implants similarly to teeth. A and B are wrong because plaque and calculus do attach strongly to implants. C is wrong because there is no significant difference between the accumulation of bacteria and calculus on implants and teeth.
Question 8: Connective tissue fibers around the implant neck are: A. Perpendicular to the implant surface
B. Not present because there is no connective tissue C. Parallel to the implant surface
D. Multidirectional
Answer: C.
The connective tissue is parallel to the implant surface, and, as a result, provides little resistance to
a probe. A is wrong because this is true for teeth only. B is wrong because a connective tissue layer of ∼1 mm is always present. D is wrong because fibers lie only in a parallel direction. Question 9: Peri-implantitis:
A. Is equivalent to gingivitis B. Cannot be treated
C. Is usually limited to superficial soft tissue D. Spreads rapidly to bone
Answer: D.
Peri-implantitis spreads rapidly to bone because of reduced resistance and blood flow at the implant neck. A is wrong because peri-implantitis is an inflammation of peri-implant tissues
leading to bone loss. B is wrong because this condition can be treated and stabilized. C is wrong because inflammation spreads to bone rapidly.
Question 10: Implant survival:
A. Is synonymous with implant success
B. Means that an implant is still present in the mouth after a period of time
C. Means that an implant is present and clinically satisfactory after a period of time D. Means that the implant required some form of treatment to avoid failure
Answer: B.
Implant survival only refers to presence in the mouth. A is wrong because “survival” and “success” have different meanings, although they are not always appropriately distinguished in the implant literature. C is wrong because it describes a successful implant. D is wrong because it describes an ailing implant.
DIAGNOSIS
Question 11: The minimum interarch space for a fixed implant-supported prosthesis is: A. 4 mm
B. 6 mm C. 7 mm
D. 12 mm
Answer: C. 7 mm
A is wrong because 4 mm would not provide room for implant components. B is wrong because it is the minimum buccolingual bone width that accommodates an implant that is 4 mm in diameter. D is wrong because it is the minimum interarch distance for an implant-supported removable prosthesis.
Question 12: Ridge mapping measures:
A. Attached gingiva by outlining the mucogingival junction B. Soft tissues on a stone model
C. Bone width on a tomogram
D. Soft tissue thickness clinically to deduce bone width
Answer: D.
Ridge mapping consists of clinical bone sounding under local anesthesia and measurement of gingival thickness to determine bone width. B is wrong, because, although the measurements resulting from ridge mapping are eventually reported on a stone model, they are derived from clinical measurement of soft tissues. A and C are wrong because they refer to clinical and radiographic measurements.
Question 13: Panoramic radiographs are useful for:
A. Ruling out bony pathologies and estimating bone availability B. Performing precise measurements of bone height and width C. Selecting the height and width of implants
D. Detecting all existing anatomic limitations
Answer: A.
Panoramic radiographs are most useful for ruling out bony pathologies and estimating bone availability. B is wrong because panoramic radiographs yield a high distortion. C is wrong
because this technique should be accompanied by other clinical and radiographic measurements. D is wrong because panoramic radiographs distort bone height and some anatomic limitations such as lingual concavities may not be seen.
Question 14: Computed tomography:
A. Is the most precise radiographic technique B. Delivers low doses of radiation
C. Is performed by a machine that is the size of a panoramic machine D. Should be prescribed in all implant cases
Answer: A.
Measurements using computed tomography are more accurate than with any other radiographic method. B is wrong because radiation doses are higher than with other dental radiographs. C is wrong because computed tomography mostly uses large costly machines found in hospitals,
although some small versions are becoming available. D is wrong because computed tomography is used for complex cases only.
Question 15: Cone beam computed tomography:
A. Is less accurate than conventional computed tomography B. Uses less radiation than conventional computed tomography C. Delivers precise bone density measurements
D. Can only be used for small regions of interest
Answer: B.
Only one scanning rotation using a cone-shaped radiographic source results in less radiation than conventional scanning. A is wrong because cone beam computed tomography (CBCT) can be more accurate than conventional CT. C is wrong because bone density evaluation is less accurate than conventional scanning. D is wrong because CBCT machines with large fields of view are able to capture full arches and a large verticcal portion of the anatomy.
Question 16: Hounsfield numbers are:
A. Values that are designed to measure bone density
B. Arbitrary numbers set for tissue density on computed tomograms C. Used in dentistry only
Answer: B.
Hounsfield numbers are arbitrary numbers set for density on computed tomograms. A is wrong because Hounsfield numbers are not specifically designed to measure bone density, although some correlation can be made. C is wrong because all computed tomography applications use Hounsfield numbers. D is wrong because this scale is used for computed tomography, not magnetic resonance imaging.
Question 17: Radiographic templates are: A. Used to visualize diagnostic teeth B. Used to measure bone density C. Used during implant surgery D. Not useful in most implant cases
Answer: A.
Radiographic templates are acrylic devices used to visualize diagnostic teeth (or ideal implant positions) on a radiograph. B is wrong because radiographic templates do not aid in evaluating bone density. C is wrong because it describe surgical guides. Although radiographic templates can be modified to become surgical guides, they are not the same. D is wrong because
radiographic templates should be used in most cases.
Question 18: A scannographic template is:
A. A requirement for aligning the mandible when taking computed tomography radiographs B. Identical to any other radiographic template
C. Useful during implant surgeries
D. An aide for visualizing diagnostic teeth on a computed tomography image
Answer: D.
A scannographic template is an aide for visualizing diagnostic teeth on a computed tomography image. A is wrong because, although highly recommended, a scannographic template is not utilized to align the mandible. B is wrong because, unlike other radiographic templates,
scannographic templates should not use metal markers. C is wrong because it refers to a surgical guide. Scannographic templates can often be modified into surgical guides.
Question 19: Which of the following statements about bone quality is true?
A. D4 bone is the densest bone B. D1 bone is the densest bone
C. There is a direct correlation between bone density and implant survival rate D. Bone quality is determined precisely based on Hounsfield numbers
Answer: B.
D1 bone is the densest bone. A is wrong because D4 bone is the most resorbed. C is wrong because there is little correlation between this classification and survival rates. D is wrong because Hounsfield numbers are an indication only of bone density.
Question 20: When selecting an implant:
A. It's best to choose the longest implant possible, because the longest implants survive best B. It's best to choose the widest implant possible, because the widest implants survive best C. Implant surface selection is critical
D. At least 1 mm of bone lingual and buccal of the implant must remain for it to survive
Answer: D.
At least 1 mm of bone lingual and buccal of the implant is necessary. A is wrong because survival rates are only compromised when implants are very short and bone density is poor. B is wrong because there is no such correlation. C is wrong because either smooth surfaces or rough surfaces can be used, although rough surfaces seem preferable.
TREATMENT PLANNING
Question 21: Screw-retained prostheses possess the following advantages: A. Ease of fabrication
B. Ease of retrieval C. Esthetics
D. Ease of connection to natural teeth
Answer: B.
A
screw-retained prostheses are not easier to fabricate, and may even be more technique-sensitive than cemented prostheses. C is wrong because screw access holes may be detrimental to
esthetics. D is wrong because there is no relationship between connection to natural teeth and the type of implant prosthesis.
Question 22: Cemented prostheses possess the following advantages: A. Ease of fabrication
B. Ease of retrieval C. Strong resistance
D. Ease of connection to natural teeth
Answer: A.
Cemented prostheses are easier to fabricate because they are identical to traditional fixed partial dentures. B is wrong because cemented restorations are more difficult to retrieve. C is wrong because there is no indication that this design is more resistant. D is wrong because there is no relationship between connection to natural teeth and the type of implant prosthesis.
Question 23: Connecting implants and teeth: A. Is forbidden
B. Is useful for consolidating teeth with reduced periodontal support C. Can be performed in all cases
D. Should be avoided whenever possible, but can be performed with careful consideration
Answer: D.
Connections between implants and teeth should be avoided whenever possible, but can be performed with careful consideration. A is wrong because connecting implants and teeth is not contra-indicated if proper measures are taken. B is wrong because implants do not consolidate teeth. Teeth, especially if there is limited periodontal support, should be treated as cantilevers from adjacent implants. C is wrong because the number of implants and spread should be considered before connecting implants and teeth.
Question 24: When treatment planning edentulous cases: A. Removable prostheses are always preferable
B. Fixed prostheses are always preferable
B. Fixed prostheses are always preferable
C. The decision between a fixed or removable prosthesis depends in part upon arch shape D. A fixed and a removable prosthesis can achieve the same goals
Answer: C.
The decision between a fixed or removable prosthesis depends upon arch shape, as well as a number of other factors including bone level and patient expectations. A, B, and D are wrong because clinical criteria and patient expectations need to be important factors in decision-making.
Question 25: Distal cantilevers on implant prostheses are: A. Always possible, with no limitations
B. To be avoided whenever possible and limited to short spans
C. Always detrimental and impossible to implement with implant restorations D. Possible when a removable full denture opposes the implant prosthesis
Answer: B.
Distal cantilevers should be avoided whenever possible and limited to short spans. A is wrong because long cantilevers are detrimental to implant restorations. C is wrong because limited cantilevers are possible. D is wrong because the presence of an opposing denture is not a criterion for placing long cantilevers.
Question 26: Immediate implant placement is:
A. The placement of an implant at the time of tooth extraction B. The placement of multiple implants at once
C. The placement of a restoration at the time of implant placement D. The placement of a restoration at the time of surgical uncovering
Answer: A.
Immediate implant placement is the placement of an implant at the time of tooth extraction. B is wrong because multiple implants are almost always placed during the same visit. C is wrong because it describes immediate loading. D is wrong because it describes loading after a waiting period.
Question 27: Immediate loading is:
A. The placement of an implant at the time of tooth extraction B. The placement of a restoration at the time of implant placement C. The placement of a restoration at the time of surgical uncovering D. The placement of a one-stage implant
Answer: B.
Immediate loading is the placement of an implant at the time of implant placement. A is wrong because it describes immediate implant placement. C is wrong because it is no longer immediate loading. D is wrong because immediate loading has no relation to the type of implant.
Question 28: Provisional restorations: A. Can rest on bone grafts and implants
B. Should not rest on bone grafts or newly placed implants C. Are not appropriate immediately after implant placement D. Are not appropriate immediately after bone grafting
Answer: B.
Provisional restorations should not rest on bone grafts or newly placed implants. A is wrong because pressures on bone grafts and implants should be avoided. C is wrong because
provisional restorations can be utilized after implant placement, as long as pressure is avoided. D is wrong because provisional restorations can be utilized after bone grafting, as long as no
pressure is placed on the grafts.
Question 29: Bone grafting:
A. Works best to augment ridge height B. Is limited to 2 mm augmentations or less C. Works best to augment ridge width D. Does not work in general
Answer: C.
Bone grafting works best to augment ridge width. A is wrong because ridge height cannot be increased predictably with bone grafting. B is wrong because 2 mm of bone augmentation is what
increased predictably with bone grafting. B is wrong because 2 mm of bone augmentation is what can be expected when increasing bone height. Greater augmentation can be achieved when increasing width. D is wrong because bone width augmentation is a predictable procedure in carefully selected cases.
Question 30: Gingival grafts should be performed: A. Prior to fabricating the final restoration
B. Preferably after the final restoration is delivered C. Only prior to implant placement
D. Only between stage one and stage two surgeries
Answer: A.
Gingival grafts should be performed prior to fabricating the final restoration. B is wrong because it is advisable to avoid gingival grafting after delivery of the final prosthesis. C is wrong because gingival grafts can be performed while implants are healing. D is wrong because gingival grafts can be performed before implant placement.
RESTORATION SEQUENCES
Question 31: Characteristics of implant-level impressions are: A. Coping placement is easy because of visibility
B. Custom abutments are not available C. Abutments must be selected in the mouth D. Abutments can be selected in the laboratory
Answer: D.
Abutments can be selected in the laboratory. A to C are wrong because they are specific to abutment-level impressions.
Question 32: Transfer-type impression copings: A. Require a hole in the impression tray
B. Are easier to utilize than pick-up copings C. Remain on the implant when the impression
D. Should be utilized in the anterior part of the mouth only
Answer: C.
Transfer copings remain on the implant when the impression is removed. A is wrong because it is specific to pick-up copings. B is wrong because no single coping type is easier than the others. D is wrong because transfer types are particularly advantageous for posterior segments.
Question 33: Pick-up type impression copings: A. Need no modification of the impression tray B. Remain in the impression when removed C. Are always more precise than transfer copings
D. Are particularly useful in the posterior part of the mouth
Answer: B.
Pick-up copings remain in the impression when it is removed. A is wrong because, in many
situations, tray modification is necessary. C is wrong because both coping types are precise. D is wrong because pick-up types are easier to use in the anterior segments.
Question 34: To verify that abutments and crowns are engaging external connection systems:
A. Tactile sense is satisfactory B. A radiograph alone is satisfactory C. No check is necessary
D. A combination of clinical and radiographic checks are recommended
Answer: D.
A combination of clinical and radiographic checks is recommended. A is wrong because tactile sense alone may be misleading. B is wrong because a misangled radiograph may mask a gap. C is wrong because a careful check is important.
Question 35: For crowns in the esthetic zone, soft tissue support: A. Can be created in the abutment only
B. Can be created in the crown only
C. Can be created in the abutment and the crown D. Can only be achieved with screw-retained crowns
Answer: C.
Soft tissue support can be created in the abutment and the crown. A and B are wrong because both the abutment and the crown can support the soft tissues. D is wrong because both cemented and screw-retained crowns can achieve tissue support.
Question 36: Implant indexing is: A. A radiographic technique
B. A method of impression-taking at the time of surgical placement C. A method of recording gingival tissues
D. A diagnostic method of determining ideal implant position
Answer: B.
Implant indexing is a method in which an impression is taken at the time of surgical placement. A is wrong because it is not a radiographic technique. C is wrong because tissues are reflected at the time of surgery and no gingival contour is available. D is wrong because it is not a diagnostic method.
Question 37: Passive fit is:
A. The placement of an abutment without resistance B. The placement of a single crown without resistance
C. The delivery of a screw without resistance until the last quarter turn D. The placement of a bridge without resistance
Answer: D.
Passive fit is a term utilized to describe placing a bridge in its full position without resistance. A and B are wrong because passive fit only refers to multiple units. C is wrong because the screw test is one of the ways to verify passive fit.
Question 38: Testing if screws can turn without resistance until the last quarter turn is: A. Useful for verifying proper fit in multi-unit restorations
B. Only useful for implant bars
C. Only useful for single restorations D. Useless in most clinical cases
Answer: A.
This test is useful for verifying proper fit, as well as lack of distortion in bridges. B is wrong
because while the test can be useful for implant bars, it is also useful for large bridges. C is wrong because it is useful for multiple units only. D is wrong because it is a useful clinical test.
Question 39: After delivery of a screw-retained bridge:
A. It is important to close the screw access hole immediately with a permanent material B. It is recommended to block the screw access hole with a temporary material
C. It is recommended to take measures so that screws will not need to be retightened at a later time
D. It is recommended to remove the bridge and reposition it at a later time
Answer: B.
After delivery of a screw-retained bridge, it is recommended to block screw access holes with a temporary material, such as Calcium oxide. A is wrong because further access to the screw may be useful during the first few months. C is wrong because torquing of screws at later visits is recommended. D is wrong because removal of the bridge has no advantage.
Question 40: For removable prostheses:
A. The male attachment is usually part of the denture
B. The attachment components do not have to be replaced
C. The female component may need replacement during maintenance D. Screws are not accessible
Answer: C.
The female components of the attachments of removable prostheses need to be checked and changed regularly. A is wrong because female components are usually part of the denture. B is wrong because replacements are necessary. D is wrong because screws retaining dentures are usually easily accessible.
MAINTENANCE:
Question 41: When using a two-stage implant, radiographic bone level is expected to be: A. At the top of the abutment
B. Flush with the implant head C. At the level of the first thread D. 4-5 mm apical to the implant head
Answer: C.
When using a two-stage implant, radiographic bone level is expected to be at the level of the first thread. A is wrong because the abutment is always coronal to bone. B is wrong because this is the bone level at the time of surgery. D is wrong because it represents bone loss.
Question 42: Mobility of an implant-supported crown generally means: A. Failure of the implant
B. Occlusal traumatism
C. Normal flexing of abutments
D. Loosening of an implant component
Answer: D.
Most often, mobility of a single implant-supported crown is a sign that an implant component has become loose. A is wrong because it is possible but very unlikely. B is wrong because occlusal traumatism may cause mobility of teeth, but mobility of an implant complex is necessarily related to another concomitant problem. C is wrong because normal mobility of components cannot be
detected clinically.
Question 43: Clinical inflammation around a single restored implant, associated with pain or pressure, but no radiographic bone loss, is most likely due to:
B. Peri-implantitis
C. Fracture of a component D. Loosening of a component
Answer: D.
Most likely, this is due to component loosening. A is wrong because implant failure is unlikely at this stage. B is possible but radiographic changes are likely. C is unlikely because the single restoration would have become detached.
Question 44: If an implant has been placed apically, a 7 mm peri-implant probing shows no sign of inflammation, and there is no radiographic change and no bleeding, this probably indicates: A. Normal functioning B. Peri-implantitis C. Implant failure D. Component failure Answer: A.
The signs suggest normal functioning. B is wrong because signs of inflammation are common with peri-implantitis. C and D are wrong because signs of inflammation and radiographic changes are likely with implant and component failures.
Question 45: At a maintenance visit, an implant-retained bar is found to be mobile at one extremity. The following should be undertaken:
A. Place a watch in the records and reevaluate at the next visit B. Refer for implant removal
C. Tighten the probable loose screw
D. Verify that the screw is loose and place a new one
Answer: D.
In this case, verify that the screw is loose and replace it with a new one. A is wrong because mobility is not going to improve. B is wrong because the implant is unlikely to be the cause of mobility. C is wrong because a loose screw should be discarded and replaced by a new one.
mobility. C is wrong because a loose screw should be discarded and replaced by a new one. Question 46: When observing a routine radiograph for an implant patient, you see a horizontal dark line between the implant and what seems to be the abutment. This is probably:
A. Normal
B. A sign of component loosening C. A sign of peri-implantitis
D. A sign of implant failure
Answer: B.
This is probably a sign of a loose component. A is wrong because almost no implant system contains a radio-clear component. C is wrong because peri-implantitis would show bone loss around the implant. D is unlikely because if implant failure had occurred a dark line would probably show along the body of the implant.
Question 47: Maintenance instrumentation for implants: A. Is identical to instrumentation used on teeth
B. Should be plastic only C. Is not necessary
D. Must not be made of stainless steel
Answer: D.
Maintenance instrumentation for implants must not be made of stainless steel, because it can scratch soft titanium. A is wrong because instrumentation used on teeth is often made of stainless steel. B is wrong because other materials are available. C is wrong because maintenance on implants is important.
Question 48: If a patient has removable dentures, what generally needs to be done at yearly visits?
A. A change of abutment screws B. A change of female attachments C. A reline of dentures
Answer: B.
Usually, female attachments of dentures are changed at yearly visits. A is wrong because screws should not be touched unless loosening occurs. C is wrong because a reline is not necessary. D is wrong because abutments are never changed.
Question 49: Which of the following should be recommended to patients for home care? A. Implant brushes
B. Any interproximal brush C. Oral rinses only
D. Superfloss or yarn
Answer: D.
Superfloss or yarn can be helpful for home care. A is wrong because special implant brushes do not exist. B is wrong because brushes with stainless steel cores should be avoided. C is wrong because oral rinses are not sufficient.
Question 50: Oral hygiene instructions for implants: A. Are identical to instructions for teeth
B. Should include specific wrap-around techniques C. Should specify staying away from implant surfaces D. Should be reserved for fixed restorations
Answer: B.
Wrap-around techniques are a recommended method of oral hygiene for implants. A is wrong because specific instructions for implants are important. C is wrong because cleaning of implant surfaces is important. D is wrong because removable appliances require cleansing of implant components and bars.
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