Comprehensive Exam Material Flashcards
When do we use an S curve?
In a class two preparation
Purpose of an S curve:
- Keeps narrow isthmus away from axiopulpal line angle
- Allows preparation to break buccal contact
- Creates a smooth & rounded outline
- Allows the buccal wall to be 90 degrees to cavosurface margin
Exposes the ends of enamel rods for a stronger bond & gives a better seal:
Gingival bevel
Why do we place a gingival bevel
Exposes ends of enamel rods for stronger bond & better seal
Where do we place a gingival bevel?
At axiopulpal line angle
When we place the gingival bevel at the axiopulpal line angle, this allows for:
Increased resistance to fracture of isthmus of restoration
What is the most common cause of fracture of the isthmus of a class II?
Lack of gingival bevel
When and why would we extend margins of the box portion of a preparation?
Sharp axiopulpal line angle - (this is why we bevel it_
What are the appropriate exit angles of buccal, lingual & gingival walls in an amalgam:
90 degrees on all
What are the appropriate exit angles of buccal, lingual & gingival walls in a composite:
Buccal & Lingual- flare, greater than 90 degrees
Gingival- 90 degrees
When would not need to place a gingival bevel?
Once you get into deeper preparations when enamel is extremely thin or you’re into dentin or cementum (because no enamel rods are present here)
Where do you place retention grooves in a box?
- Buccal-axial line angle & lingual-axial line angle
- Just inside the DEJ, entirely in dentin
When placing a retention groove in a box, the groove does not go into:
Gingival floor
Label the following image:
A) gingival-axial line angle
B) buccal-gingival line angle
C) buccal-gingival axial point angle
D) buccal-axial line angle (with optional retention groove)
E) axiopulpal line angle
F) lingual-axial line angle (with optional retention groove)
G) Iingual-gingival axial point angle
H) lingual-gingival line angle
List the advantages of composite resin: (6)
- Esthetics
- Conservation of tooth structure
- Bonding
- No metal
- Can be economical (compared to crowns inlays/onlays)
- Prep more forging (restoration is not)
Why is it advantageous that composite resin incorporates bonding: (2)
- Reduced microleakage and recurrent decay
- Increased retention
Why is it advantageous that composite resin does NOT incorporate metal: (3)
- No mercury arguments from patients
- No corrosion
- No galvanic shock
List order of expensive from to least to greatest:
-Crowns & inlays/onlays
-Amalgam restorations
-Composite restoration
- Amalgam
- Composite
- Crowns/inlays/onlays
What are the disadvantages of composite resin: (9)
- Low modulus of elasticity
- Porous
- More technique sensitive placement
- More time-consuming placement
- Microleakage
- Pull back, can create voids
- Expensive compared to amalgam
- Cannot place in bulk
- Cannot support occlusion
What do we mean by “composite cannot support occlusion”
Must have tooth supported occlusion on marginal ridges & cusp tips
What is the purpose of using a wedge in a class II preparation?
Closed the margin in the gingival of the box & prevents overhang
When using a tofflemire retainer band the narrower opening faces:
Gingivally
What way should the opening slits of the tofflemire face?
Gingivally
Why should the opening slits of the tofflemire face ginivally?
So when you release the Tofflemire it comes off the tooth toward the occlusal surface
How to troubleshoot errors in proximal box restorations: (2)
- Choose correct wedge (size/shape) & properly seat it
- Properly condense amalgam
Properly condensing amalgam prevents:
Voids into point angles
Choosing the correct size & shape of wedge as well as correctly placing the wedge ensures:
Good contour of gingival margin
This instrument should be used in a proximal box restoration to press and wiggle into internal line angles (BG & LG), against margin areas, and contact areas of the band:
Hollenback condensor
What instrument should be used for the pre-carve burnishing in the proximal box of an amalgam restoration?
Side of Hollenback condensor
What instrument should be used in a proximal box restoration for defining occlusal embrasure by using at a 45 degree angle?
Explorer
An explorer can be used to define the occlusal embrasure of a proximal box restoration by holding it at:
45 degree angle
What instrument is used for forming grooves and carving the marginal ridge in the proximal box of an amalgam restoration:
Hollenback carver
What instrument should be used to redefine the occlusal embrasure?
Explorer
In a class II restoration what instruments should be used to:
a) Carve excess off buccal & lingual walls of box
b) Break corner off marginal ridge
c) Carve embrasures
Hollenback carver
In a class II restoration what instruments should be used to:
a) carve away gingival margin excess
b) instruments drawn laterally or occlusally
Hollenback carvers held obliquely OR Wiland carver OR 34-35 Jaquette scaler
In a class II restoration what instruments should be used when amalgam is partially set and you need to adjust occlusion:
Discoid carver
In a class II restoration what instruments should be used to redefine groove anatomy after doing final occlusal adjustment:
Hollenback carver or Cleoid carver
In a class II restoration what instruments should be used to smooth surfaces in bottoms of grooves:
Beavertail burnisher
Bond agent that does NOT require a separate etch step:
Self etch
Requires etch, rinse & then bond agent:
Total etch
When you only etch the enamel, avoiding dentin (20-30 sec)
Selective etch
A selective etch as opposed to a complete etch may:
Reduce sensitivty
What should be avoided when doing a selective etch?
Dentin
How long should the etch stay on in a selective etch?
20-30 seconds
When you place etch all over the enamel & dentin:
Complete etch
Describe the process of a complete etch:
- Etch is placed over the enamel first for 20-30 sec
- Etch is placed on the dentin for 15-20 sec
How should composite resin be placed?
Incrementally not exceeding 2 mm at a time (no bulk fill)
An uncured layer of composite in which oxygen interferes with the polymerization:
Oxygen inhibited layer
When is the oxygen inhibited layer removed?
Removed with finishing & polishing
The oxygen inhibited layer is a _____ thick layer which on the outside allows addition & wetting of subsequent layers of _____
15 microns
Composite
The oxygen inhibited layer is ______ % ______ to co-polymerize with the new material
50%; unreacted methacrylate groups
In an older restoration (no unreacted methacrylate groups), the repair strength=
50% original restoration (roughen with diamond)
Excavators & chisels are considered _____ instruments:
Cutting
Amalgam condenser, mirrors, probes & explores are considered _____ instruments:
Non-cutting
On the end of a non-cutting instrument, what is present?
Face & nib
On the end of a cutting instrument, what is present?
Blade with cutting edge
Which instruments are best for different stages for carving anatomty?
- Plastic instrument
- Hollenback carver
- Optrasculpt
Instrument used to place & smooth composite on occlusal surface:
Plastic instrument
Instrument used to carve anatomy, primarily for amalgam:
Hollenback carver
Instrument used to develop anatomy in composite resin prior to light curing:
Optrasculp
After light curing, what should be used to develop anatomy in composite resin:
Carbide burs for finishing
What is a “swivel”?
Allows ergonomic manipulation of the handpiece between the dental unit
Where is the motor located in a handpiece?
Motor located in actual handpiece
What is the purpose of water when drilling with a handpiece?
- Cools area of contact between bur & tooth structure to prevent pulpal irritation
- Avoids heat build up & destruction of odontoblastic processes in the dentin (dead tract)
Heat buildup causing destruction of the odotontoblastic processes in the dentin leads to:
Dead tracts
-uses steam under pressure
- 250 degrees, 15 PSI, 20 minutes
-Shelves for cassettes
Autoclave
-Oven-type sterilizer
- 320 degrees F, 60 to 120 minutes
Dry heat
-Chemical vapor pressure
-Uses chemical solution in a pressurized chamber
- 270 degrees F, 20-40 PSI, 20 minutes
-Proper ventilation must be installed
Chemiclave
-Several hours BELOW 100 degrees C
-Proper ventilation must be installed
Ethylene oxide
Temp, pressure & time requirements for sterilization via autoclave:
250 degrees F
15 PSI
20 minutes
Temp & time requirement for dry heat sterilization:
320 degrees F
60-120 minutes
Temp, pressure & time requirements for chemiclave sterilization:
270 degrees F
20-40 PSI
20 minutes
Temp & sterilization requirement for ethylene oxide sterilization:
Several hours below 100 degrees C
The STATIC relationship between incising & masticating surfaces between the maxillary teeth or tooth analogues:
Occlusion
The STATIC & DYNAMIC contact relationship between occlusal surfaces of teeth during function:
Articulation
Occlusion can be described as a ______ relationship:
Static
Articulation can be described as a ______ relationship:
Static & dynamic
Forces are directed over the long axes of teeth:
Axial loading
In axial loading, forces are directed:
Over the long axes of teeth
Type of contact:
When each functional cusp occludes in a fossa of the opposing tooth
Cusp-fossa contacts
Type of contact:
Commonly used for single restorations
Cusp-marginal ridge contacts
Type of contact:
Majority of natural dentition have this
Cusp-marginal ridge contacts
Type of contact:
Not seen alot in nature
Cusp-fossa contacts
Type of contact:
Used when restoring both opposing quadrants
Cusp-fossa contacts
Type of contact:
Tooth-to-tooth arrangment
Cusp-fossa contacts
Type of contact:
Each functional cusp contacts the MR of opposing pair of teeth or fossae of opposing teeth
Cusp-marginal ridge contacts
Type of contact:
A one tooth to two teeth arrangement
Cusp-marginal ridge contacts
-Each functional cusp occludes in a fossa of the opposing tooth
-Tooth-to-tooth arrangement
-Used when restoring both opposing quadrants
-Not seen alot in nature
Cusp-fossa contacts
-Each functional cusp contacts the MR of opposing pair of teeth or fossae of opposing teeth
-A one tooth to two teeth arrangement
- Majority of natural dentitions have this
-Commonly used for single restorations
Cusp-marginal ridge contacts
When cusp-fossa contacts to cusp-marginal ridge contacts which one is superior?
One is not proven better than the other
This occlusal relationship allows for some cusps to occlude onto MRs and others to occlude into fossae:
Cusp-marginal ridge occlusal relationship
This occlusal relationship allows ONLY for each cusp to occlude into one fossae:
Cusp-fossa relationship
Key aspects of nutritional counseling for patients with HIGH caries rates:
- Identify sources
- Reduce frequency & ingestion
Describe Silver Diamine Fluoride
-Silver in color and used to arrest caries
-Primarily used on children who will lose the primary teeth
-Used on occlusal caries in the mouth that may be hard to get to
- Very dark color
-NOT esthetically pleasing
Fluoride toothpaste should be given to patients with:
Root caries
Enamel with fluoride pH=
4.5
-No clinically detectable lesion
-Dental hard tissue appears normal in color, translucency & gloss
Clinical presentation:
Sound
Sound tooth structure radiographically will be labeled as:
E0 or R0 (no radiolucency)
-Earliest clinical detectable lesion compatible with mild demineralization
-Lesion limited to enamel or shallow demineralization of cementum/dentin
-Mildest forms are detectable only after drying
-When established or active, lesions may be white or brown
-Enamel has lost its normal gloss
Clinical presentation:
Initial
If caries are classified as initial, they are visually:
Noncavitated
Initial caries radiographically will be labeled as:
E1, E2 OR D1 (Radiolucency may extend into the DEJ or outer 1/3 of the dentin)
-Visible signs of enamel breakdown
-Signs the dentin in moderately demineralized
Clinical presentation:
Moderate
Moderate caries may also be classified as:
Established, early cavitated, shallow cavitation, or microcavitation
Radiographically, moderate caries will be labeled as:
D2 (Radiolucency extends into middle 1/3 of dentin)
-Enamel is fully cavitated
-Dentin is exposed
-Dentin lesion is deeply/severely demineralized
Clinical presentation:
Advanced
Advanced caries may also be classified as:
Spread/disseminated, late cavitated, deep cavitation
Radiographically advanced caries will be labeled:
D3 (Radiolucency extends into the inner 1/3 of the dentin)
No radiolucency:
E0 or R0
Radiolucency may extend to the DEJ or outter 1/3 of the dentin
E1, E2 or D1
Radiographs are not reliable for:
Mild occlusal lesions
Radiolucency extends into the middle 1/3 of the dentin:
D2
Radiolucency extends into the inner 1/3 of dentin:
D3
What is the brand name for resin infiltration?
ICON
Resin infiltration is treatment for:
- Initial (incipient) caries
- Mild fluorosis
- White & brown spot lesions
- Class II
Resin infiltration (ICON) can penetrate into:
Outer 1/3 of dentin (D1)
Resin infiltration (ICON) can be described as:
Micro-invasive
What resin infiltration is used in our clinic?
ICON
List steps to prior to applying resin infiltration (ICON):
- Clean tooth well (pumice)
- Dry working field (rubber damn)
- Etch for atleast 30 sec 1-3 time; rinse & dry well
ICON etch is:
15% hydrochloric acid gel
ICON etch acts as a:
“Chemical drill”
Finishing & polishing a composite restoration:
The occlusal surface is shaped with a _____ or _____ finishing bur or similarly shaped finishing _____
Round or oval carbide; finishing diamond
What instrument in needed to attach a finishing disc to the handpiece?
SOFLEX mandrel
Cause of dentinal sensitivity:
Hydrodynamic theory of pain transmission
Hydrodynamic theory of pain transmission:
Dentinal tubules are filled with _____ and wrapped in _____ & ____
Odontoblastic processes; afferent nerves; dentinal fluid
Hydrodynamic theory of pain transmission:
When enamel or cementum is removed during cavity preparation, the _____ of dentin is lost which allow _____ in the tubules. This movement causes distortions in the afferent nerve hence pain
External seal; small fluid movements
Hydrodynamic theory of pain transmission:
_____ changes within the tubules caused by _____ can cause pain to the pulp through fluid movement within the tubules
Hydrostatic pressure; external stimuli
What are example of external stimuli that changes in hydrostatic pressure leading to pain:
Temperature change, high speed handpiece, air drying, osmotic changes from various chemicals, caries
Used when a deep carious lesion occurs and their no clinical or radiographic evidence of irreversible pulp damage:
Indirect pulp cap
Evidence of pulp damage, that is likely irreversible:
-History of spontaneous pain
-Heat sensitivity relieved by cold
-P.A. lesion
For an indirect pulp cap, the tooth should be:
- Completely asymptomatic
- Show signs of reversible pulpitis
If a patient is experiencing moderate cold sensitivity with pain subsiding within about 15 seconds this is evidence of _____ & we would use _____
reversible pulpitis; INDIRECT pulp cap
Caries are usually _____ than they appear to be on a radiograph
Deeper
What is the objective of an INDIRECT pulp cap:
To avoid a direct pulp exposure
What are the two approaches that might be termed indirect pulp cap?
- The two-appointment approach
- The single-appointment approach
Describe the sequence of steps at the first appointment in the two-appointment approach of an indirect pulp cap:
- All caries removed from all areas except the deepest, nearest pulp
- Leave the last bit of infected dentin to avoid pulp exposure
- Cover remaining infected dentin with Calcium hydroxide (Life or Dycal) and then glass ionomer (Vitrebond)
- Place a temporary restoration (IRM)
- It may be acceptable to leave some undermined enamel (temporarily) to help hold in the temporary restoration
Describe the sequence of steps at the second appointment in the two-appointment approach of an indirect pulp cap:
- Remove temporary restoration, glass ionomer & Calcium Hydroxide
- Carefully remove infected dentin (soft, leathery caries)
- Leave the affected dentin (dry, powdery caries)
How long should allow in between the first & second appointment in the two-appointment approach to indirect pulp capping?
Allow 6-12 weeks
Why should you allow 6-12 weeks between first & second appointments in the two-appointment approach to indirect pulp capping?
Allows the body to form reparative dentin in site near exposure
The desired result in the 6-12 week period between appointments in the two-appointment approach=
Dentin bridge formation
In the two-appointment approach to indirect pulp capping, at the end of the 12 weeks confirm that the patient is _____ & that the tooth is ____
Asymptomatic; vital
In the two-appointment approach to indirect pulp cavity, research has suggested that if the cavity has been well-sealed in the twelve week interval and if the patient is asymptomatic and the tooth tests vital, the tooth may:
Not need to be re-entered
What is the benefit of not re-entering the tooth if the criteria is met?
Avoids risking the pulp exposure
What is the theory behind to two-appointment approach to indirect pulp capping?
Food supply to bacteria is cut off by the well sealed restoration so they die or become dormant
Where does confusion arise with the two-appointment approach to indirect pulp capping?
Its clinically impossible to determine infected from affected dentin
When are direct pulp caps used?
When small pulpal exposure occurs during cavity prep
For a direct pulp cap, a thin layer of ______ (_____) is floated over the exposed pulp
Calcium hydroxide (Dycal)
For a direct pulp cap, a thin layer of calcium hydroxide (dycal) is floated over the exposure pulp and then a layer a _____ is placed over the calcium hydroxide. This may help stimulate the pulp to form ______ which can produce a ______ across the exposure site
Glass ionomer (Vitrebond)
Secondary odontoblast
Dentin-bridge
A direct pulp cap is most successful when the exposure is _____ rather than _____
Mechanical; carious
A direct pulp cap is most successful when the patient is _____ & the exposure site is less than _____
Young; 0.5mm
A direct pulp cap is most successful if bleeding at the site is _____ and there is no ____ or _____
Controlled; Pus or serous exudate
A direct pulp cap is most successful if the area has not been:
Contaminated by saliva
A direct pulp cap is most successful if there ha been little or no _____ to the ____
Mechanical damage to the pulp tissue
In a direct pulp cap _____ may cause canals to calcify over time
Calcium hydroxide (CaOH)
When should you NOT rely on a direct pulp cap?
If tooth requires crown to adequately restore
Direct pulp caps occur better at the _____ than they do on an exposure on the _____ (as from a Class V lesion)
Tips of pulp horns; side of a pulp chamber
Direct pulp caps are more effective on ______ patients with _____ pulp chambers & ______ root canals that provide better ____ to the area where we are trying to induce dentin bridge formation
Young; large; open; circulation
If the tooth will require a crown to adequately restore it than you should:
NOT RELY ON A DIRECT PULP
A pulp tissue’s reaction to stimuli is related to its response to irritation by:
- Mechanical stimuli
- Thermal stimuli
- Chemical stimuli
- Bacterial stimuli
The deposition of reparative dentin by secondary odontoblasts lining the pulp cavity acts as a ____ against ______ and various other irritating factors
Protective barrier; caries
Describe the formation of reparative dentin:
Continuous & slow process
Describe the timeline of formation of reparative dentin:
Takes 100 days to form reparative dentin layer that is 0.12mm thick
In cases of severe irritation, the pulp responds by an _____ similar to any other soft tissue injury. However, the inflammation may become _____ & can result in ____
Inflammatory reaction; irreversible
Death of the pulp
Death of the pulp due to an inflammatory reaction can occur because of the _____, _____ structure of the dentin limiting the inflammatory response & the ability of the pulp to _____
Confined, rigid structure; recover
Many teeth have pulpal sensitivity due to caries or following cavity preparation or restoration
This would be an example of:
Reversible pulpitis
A twinge of pain may be due to sugar, cold or acid from caries first contacting dentin. Pain lasting a few seconds may be due to the irritant continuously present or applied repeatedly.
This would be an example of:
Reversible pulpitis
Reversible pulpitis causes an increased _____ & ____ (_____) and inflammation of the pulp
Blood flow & volume (hyperemia)
As long as an irritant, such as touching an ice stick to the tooth causes pain that lingers no more than 10 to 15 seconds after removal, it’s called _______ and can be treated with a _____
Reversible pulpitis
Restoration
When pain is either spontaneous, or–if elicited by an irritant– lingers more than 15 seconds, _____ has occurred and resolution by operative dentistry treatment is _____
Infection of the pulp; usually not possible
Treatment that is advised for irreversible pulpitis:
Root canal
Results when irreversible pulpitis is left untreated:
Pulpal necrosis
Characterized by spontaneous, continuous, or throbbing pain or pain elicited by heat that can be relieved by cold & then, later, with no response to any stimulus:
Pulpal necrosis
As inflammation & infection move beyond the _____ the tooth may become __________
Root apex; sensitive to percussion
Alternative causes of dental pain that are NOT pulpal in origin: (3)
- Maxillary sinusitis
- Cracked tooth
- Occlusal trauma
Usually manifests as cold sensitivity, and sometimes spontaneous pain in the maxillary posterior teeth. Often hard to isolate to a single tooth:
Maxillary sinusitis
Usually manifests as cold sensitivity, or a sudden–usually unreproducible– pain when chewing:
Cracked tooth
Instrument that can often elicit pain when placed between the teeth in the central groove areas or at the tips of individual cusps
Tooth sleuth
Cracks in a tooth can sometimes progress into the pulp chamber and cause:
Pulp necrosis
Tooth cracks can sometimes be seen externally with a ______ or it may be necessary to remove restorations to see them
Fiber optic light
Treatment for cracked tooth:
Crowning
Usually manifests as cold sensitivity or pain with chewing. Slight tooth movements when the teeth are clenched and them moved from side to side may be seen, but not always:
Occlusal trauma/fremitis
Occlusal trauma pain/fremitis can often be relieved by:
Occlusal adjustments
Neutral position for dentist include:
Describe head position:
Head at 0-20 degree tilt; ears over shoulders
Neutral position for dentist include:
Shoulder over _____ & _____ relaxed at sides
Hips; elbows
Neutral position for dentist include:
Forearms should be _____ or slightly ____
Parallel to floor; upward
Neutral position for dentist include:
Describe back position:
Slight curve in lower back: lordosis
Neutral position for dentist include:
Hip angle _____, ideally ______ (Hips higher than ____)
Greater than 90 degrees; ideally 105-125 degrees; knees
Neutral position for dentist include:
Describe foot position:
Feet flat on floor in tripod position
CTD:
Cumulative trauma disorders
What is the main cause of musculoskeletal disorders (MSD) in dentistry:
Cumulative trauma
The primary cause of disability among dentist:
Cumulative trauma disorders
In CTD, microtrauma occurs on the _____ level with damage that ____
Cellular level; accumulates
The greatest strength of dental materials is usually _____ while the weakest strength is _______
Compressive strength; tensile strength
To resist masticatory (chewing) stresses without fracture:
Resistance
-Walls parallel or perpendicular to forces
-Rounded line and point angles
-Flat and smooth walls
-Giving bulk to restoration
These are all:
Factors contributing to resistance
To retain the restoration securely during function:
Retenion
-Wall convergence (undercut)
-Taller wall
-Dovetail
These are all:
Factors contributing to retention
Converging walls is especially important in:
Amalgam
Taller walls will increase _____ (resists the pull of sticky food)
Frictional retention
What is the purpose of a dovetail?
Prevents tipping and proximal displacement
Form that allows you to access the defect:
Convenience form
Allows you to see what you are doing, ideally with perfect ergonomics:
Convenience form
The cavosurface is the junction of the _____ cavity wall & the _____ surface of the tooth
Prepared; external
The cavosurface is the junction of the _____ cavity wall & the _____ surface of the tooth
Prepared; external
