Class II review Flashcards
1
Q
CLASS II COMPOSITE RESTORATION
PLACEMENT
* Foundations are the same as for amalgam restoration
* Additional steps to prepare tooth for bonding
(4)
A
- Etch (and rinse), Bond Agent placement (gentle dry, light cure), composite placed
incrementally, light cure each increment
2
Q
CLASS II COMPOSITE RESTORATION
PLACEMENT
* More challenging to establish good contact
A
- Composite does not displace the matrix band like amalgam
- Shrinkage occurs as you light cure
- Different type of matrix may help counteract this issue
3
Q
ETCH- Complete vs. Selective
* Complete
(5)
A
- Place etch on enamel first, followed by
dentin - ETCH ENAMEL 20-30 SECONDS
- ETCH DENTIN 15-20 SECONDS
- Rinse and gently air dry
- Typically only done with total-etch and
universal bond agents
4
Q
ETCH- Complete vs. Selective
* Selective
(5)
A
- Etch enamel only
- 20-30 seconds
- Rinse and air dry
- Can only be done with certain bond agents
- Universal (what we use in clinic and lab) and Self
-etch types
5
Q
Wash and dry enamel thoroughly
* Rinse and dry thoroughly.
(2)
A
- Be sure to dry on both sides of the matrix band and around the proximating teeth. Check for the whitish etched enamel surface. Re-apply the etchant if there is not clear evidence of etched enamel.
- It may be appropriate to re-etch for 10 seconds if the enamel or dentin is contaminated with saliva then wash, dry apply bonding/primer agent, cure and continue.
6
Q
Do not desiccate the dentin
This results in …
* Optional:
A
collapse of collagen layer (more on that later) and reduced bond strengths
- Place a cotton pellet over the dentin to avoid desiccating it
7
Q
Apply Bond Agent
A
- Always read directions!
- Apply bond agent
- Gently push bond agent into tooth
- Brush on THIN layer
- Avoid letting bonding agent pool in your prep
- Gently blow air
- Thins bond agent
- evaporates solvent
- usually acetone, ethanol, or water
- Cure 20 seconds
- refer to your light’s guidelines
8
Q
Place composite incrementally
(3)
A
- Place the first layer of composite resin in the proximal box to a depth
of about 1mm - Some use flowable for first layer
- Can leave flowable uncured and place regular composite on top
- Adapt well into the preparation and against the matrix band with a
small condenser - Cure 20 seconds
9
Q
First Increment
(3)
A
- Most important increment at gingival wall
- May use flowable composite here
- “layering” technique
- Make sure it is adequately cured
10
Q
Add additional increments. The increments should not exceed
A
2 mm.
11
Q
This method of placement minimizes stresses placed on the material and on the tooth due to —.
This may be a factor in —
A
polymerization shrinkage
postoperative sensitivity
12
Q
Establishing interproximal contact
(3)
A
- Press the matrix band firmly against the marginal ridge of the proximating
tooth with the side of a metal condenser while curing the initial
increments. - This helps to obtain a good contact.
- Palodent Plus shapes this for you
13
Q
- Form the final anatomy using
A
plastic instrument
* Finish as well as possible BEFORE curing!
* Must work quickly
14
Q
- Form the outer incline of the marginal ridge
A
- MARGINAL RIDGE SHOULD BE ROUNDED
- Not flat
- Flat shreds floss
15
Q
Forming anatomy in composite is more like waxing lab than amalgam
* Except
A
your in a slight time crunch
* Overhead lights will cause composite to polymerize
16
Q
Final Cure
(3)
A
- Remove the matrix
- Cure the restoration from the buccal 20* sec
- Cure the restoration from the lingual 20* sec
- This cures the areas that were covered by the opaque matrix band
17
Q
ways voids are created
(2)
A
- Composite can stick to an instrument and upon pulling back, a void is
created - When injecting the material, lifting the syringe may cause tug back and
a void is created
18
Q
Consider using — composite in the box if you can’t place
composite without creating a void
A
flowable
19
Q
Finishing and Polishing Composite
* These steps:
(4)
A
- Removes the oxygen inhibited layer
- Establishes anatomy/final shape
- Ensures a smooth surface
- EXTREMELY IMPORTANT IN COMPOSITE
- Major difference between amalgam and composite
20
Q
Finishing composite
instruments (3)
A
Plastic/composite instrument
Optrasculpt
* Esthetic Trimming Carbides
21
Q
Esthetic Trimming Carbides
(3)
A
- Use to finish and refine surface PRIOR to polishing
- High speed handpiece
- NOT at full power
- Use light, brushlike, sweeping motion with bur
22
Q
Finishing composite
Proximal walls
discs (2)
A
- Can use discs to finish, if necessary
- Discs available in lab are very abrasive
23
Q
Only after properly finishing composite restoration can
you polish!
* If left rough or scratchy,
A
the polishing paste will stick in irregularities and
make appearance worse
24
Q
We use points and discs that are impregnated with
A
polishing paste
* Used in latch-type head of electric handpiece on polishing speed
* Get them slightly wet and use them to polish your restorations to a high
luster
25
Checking occlusion and contact
(4)
* Remove rubber dam
* Compare occlusion to adjacent tooth
- marginal ridge height should be even
* Check occlusion with articulating paper
- Make sure there are no occlusal prematurities
- If there are, remove with finishing carbide
* Assess contact with floss
26
Polishing composite
(2)
Polishing composite
* Polishing of composite should be completed on the SAME DAY as it is placed
* Polishing must be completed after properly finishing composite
27
* Proper finishing and polishing:
(2)
* INCREASES LONGEVITY OF RESTORATIONS
- Improved marginal integrity
- Plaque resistant surface
* Improves esthetics
- Improved contours
* Undetectable margins
- Healthier gingiva
28
The matrix band can
contribute to proper or
improper contours, but since
it is relatively soft,
it can be
pushed in appropriate
directions while packing
amalgam to develop proper
contours & line angles.
29
CONSIDERATIONS FOR DEEPER
LESIONS
(3)
* Liners, sealers, and bases under amalgam
Liners, sealers, bases NOT NECESSARY for every preparation
30
UMKC uses
ADMIXED alloy (Dispersalloy)
31
no sealer nor liner is necessary (2)
Preparations ideal, OR deeper than normal, BUT with 1.0-2.0mm dentin
between pulp and restorative material
32
Preparations deeper than normal with LESS THAN 1.0mm dentin
between the pulp and the restorative material= use
RMGI liner
* Resin Modified Glass Ionomer
* Thermal insulator
33
Preparations with LESS THAN 0.5mm of dentin between the pulp and
restorative material= use
thin layer of calcium hydroxide followed by
a later of RMGI
34
Preparations with a direct pulp exposure on vital pulp=
0.5mm thick
calcium hydroxide layer followed by layer of RMGI
35
The --- is an
extremely sensitive part
of the tooth. This is
where enamel and dentin
meet.
dentino-enamel
junction (DEJ)
36
Hydrodynamic theory of pain
transmission
(3)
* (most accepted theory of pain transmission).
* Dentinal tubules are filled with odontoblastic processes and wrapped in afferent nerves and dentinal fluid.
* When enamel or cementum is removed during cavity preparation, the external seal of dentin is lost, which allows small fluid movements in the tubules. This movement causes distortions in the afferent nerve endings, hence, pain.
37
Hydrostatic pressure changes within the tubules caused by external stimuli (eg., Temperature change, high speed handpiece, air drying, osmotic changes from various chemicals, caries, etc.) can cause
pain to the pulp through fluid movement within the tubules.
38
Air-water spray should be used whenever cutting
with high-speed handpieces to avoid
heat build up
and the destruction of the odontoblastic processes in
the dentin (dead tracts).
39
Dentin should not be --- by air blasts, as this
could cause aspiration of odontoblasts into tubules.
dehydrated
40
Dentin should not be --- by air blasts, as this
could cause aspiration of odontoblasts into tubules.
dehydrated
41
Caries control restorations are performed, as part of a larger caries control plan, when one or more of these conditions exist:
(4)
1. Caries is extensive enough that pulpal complications are likely to occur soon.
2. It is desirable to quickly eliminate large carious lesions that are a source for caries infection in the patient’s mouth.
3. Time does not permit definitive restoration of one or many large lesions.
4. The prognosis for the pulp is questionable, and definitive restoration should be deferred until the pulp’s condition can be better assessed.
42
Caries control restorations refer to a situation when one
tooth, or multiple teeth at the same appointment, are treated
quickly by:
(3)
1. Removing the infected dentin
2. Medicating the pulp, if necessary
3. Restoring the defects with a temporary material.
If a temporary material is used, undermined
enamel can be left to better retain the temporary.
43
The Indirect Pulp Cap
Used when
a deep carious lesion occurs and there
is no clinical or radiographic evidence of
irreversible pulp damage (such as a history of
spontaneous pain, heat sensitivity relieved by cold,
or a P. A. lesion). Tooth should be asymptomatic,
or—at most—have symptoms consistent with
reversible pulpitis, such as moderate cold
sensitivity, with pain subsiding within about 15
seconds. Remember, caries is usually deeper
than it appears to be on X-ray.
44
THE OBJECT OF AN INDIRECT PULP CAP IS TO
AVOID A DIRECT PULP EXPOSURE.
45
Liner Placement
(2)
Add a liner only to the deepest parts of the preparation, closest to the pulp.
Keep the liner material away from the margins.
46
Liner materials:
(2)
* Calcium hydroxide
* Resin Modified Glass Ionomer
47
Calcium hydroxide
(2)
* Brand names: Life, Dycal
* Use on deepest preps- pulp capping material
48
Resin Modified Glass Ionomer
((3)
* Brand name: Vitrebond
* Light cured
* Releases fluoride over time
49
There are two approaches that might be termed “indirect pulp cap”:
The Two-Appointment Approach:
Done when the removal of all the infected (soft, leathery)
dentin is most likely going to result in a pulp exposure:
* Remove all caries, both affected and infected dentin,
from all areas except the deepest, close to the pulp.
* Leave the last little bit of infected dentin, cover it with
calcium hydroxide (Dycal or Life), and glass ionomer (Vitrabond).
* Place a temporary restoration, such as IRM or Ketac Silver.
It is OK to leave some undermined enamel temporarily to
help hold in the temporary restoration.
* Wait several weeks—perhaps twelve weeks, if possible—to allow the body to form reparative dentin in the site of the near exposure. If we get the desired result, a dentin bridge will have formed.
* At the end of the twelve weeks, confirm that the patient is asymptomatic, and do a vitality test before anesthetizing.
* Traditional approach: Remove the temporary restoration, the glass ionomer, and the CaOH, and carefully remove the remaining infected dentin (soft, leathery caries). Leave the affected dentin (dry, powdery caries). A #4 round bur, used on the slow speed handpiece, just above stall speed, with a light, shaving touch is probably the best choice for this function. It is better than a spoon excavator, since the larger bur will put less force per unit area than the hand instrument would do, therefore making it less likely that one would break through into the pulp. Place a new liner of Dycal, if desired, covered by a base of Vitrabond. Remove all undermined enamel, modify the prep. to properly retain the restoration, and restore with your selected permanent material.
* Research has suggested that—if the cavity has been well sealed during the twelve week interval, and that if the patient is asymptomatic and the tooth tests vital, a dentist might choose to not remove the CaOH liner and glass ionomer base at the second appointment, and might, therefore, leave the SMALL amount of infected dentin that was sealed deep in the cavity beneath the liner and base, rather than risk an exposure at the second appointment. The theory is that the food supply to the bacteria will be cut off by a well sealed restoration and that the bacteria will die or become dormant. Caries progression, these researchers believe, will be arrested, and the pulp will remain in good health. This is an evolving area of thought in dentistry, and you will encounter different opinions & a degree of confusion on this issue, even among dental school professors. Some of the confusion arises from the fact that it is impossible to determine clinically exactly where infected dentin stops and affected dentin (not invaded by microorganisms) begins, there is some disagreement about how much is O.K.
50
The Single-Appointment Approach
(By Far, the Most Common) (By Far, the Most Common
* Remove infected (soft, leathery) dentin. Remove affected dentin (dry, powdery caries) from any areas where a pulp exposure is not likely to occur (anywhere close to the D.-E. junction).
* Leave the affected dentin (dry, powdery caries) only in the deepest area where the possibility of a direct pulp exposure is a concern.
* As I already mentioned, recent research confirms it is permissible to leave a small amount of infected dentin in deep areas, as well, to avoid a direct exposure.
* Place a liner of CaOH (Dycal or Life) over the deepest area, close to the pulp.
* Place a base of glass ionomer (Vitrabond) over the CaOH. There is fluoride release from the Vitrabond. If sealed off from the oral environment, remineralization of the affected dentin is possible.
* If at all possible, remove all undermined enamel and place the “permanent” restoration, so that you do not need to re-enter the tooth and risk an accidental exposure .
* If time does not permit placing the “permanent” restoration (if, for instance, you are trying to do temporary, caries control restorations in several teeth at the same appointment), place a temporary restoration. Come back at another appointment to complete the definitive restoration (or buildup—for instance, a pin-retained amalgam buildup in anticipation of a crown). Do not remove the vitrabond or Dycal—why risk a pulp exposure?
* If the restoration is deep, and perhaps the patient had some symptoms of reversible pulpitis, it would be prudent to wait several months before completing a crown if one is necessary. Confirm that the tooth remains symptom free and tests vital before crowning.
51
Direct pulp cap
* Used when
a small pulpal exposure occurs during cavity preparation.
52
Direct pulp cap
A thin layer of calcium hydroxide is floated over the exposed pulp. A layer of glass ionomer is placed over the CaOH. This may help stimulate the pulp to form secondary odontoblasts, which can produce a dentin bridge across the exposure site.
53
skipped
It is most successful when the
exposure is mechanical rather than
carious,
(3)
* when the patient is young, in exposure
sites less than 0.5 mm,
* if bleeding at the site is easily controlled
and there is no pus or serous exudate
* if the area has not been contaminated by
saliva, and
* if there has been little or no mechanical
damage to the pulp tissue.
54
Endodontists aren’t fond of direct
pulp caps since
CaOH may cause the
canals to calcify over time.
55
There is a very real chance that the pulp cap will not work. Confirm vitality some months later with a (2)
radiograph and some form of pulp testing (electric pulp test, cold test).
56
Pulp caps are more effective on
young patients with large pulp chambers and open root canals that provide better circulation to the area where we are trying to induce dentin bridge formation.
57
Direct pulp caps work better at the
tips of pulp horns than they do on an exposure on the side of a pulp chamber (as from a class V lesion).
58
Mild to moderate spontaneous pain for as much as --- after the procedure may not indicate the need for endodontics, but after that, spontaneous pain is more ominous. Some cold sensitivity may linger for several weeks.
three days
59
If the tooth will require a crown to adequately restore it,
DO NOT RELY ON A DIRECT PULP CAP . Do endodontics before crowning teeth that have had direct exposures, and, if necessary, a form of endodontic post reinforcement before crowning.
60
A broken or leaky restoration = failure because
bacteria will leak into the pulp and kill it.
61
ALL Restorations must adequately seal the cavity to avoid (3)
microleakage, bacterial penetration, and—of course—recurrent decay.
62
Whenever dentin has been cut, a --- layer is created.
smear
63
Whenever dentin has been cut, a smear layer is created.
* It’s a few micrometers thick and is composed of
denatured collagen, hydroxyapatite, and other cutting debris.
64
Whenever dentin has been cut, a smear layer is created.
It acts like a natural bandage over the cut surface since it
occludes many of the dentinal tubules with debris called smear plugs. While it is a good protective barrier, it is relatively weak and can be dissolved with acids.
65
We do not want to bond to the smear layer when using
“total etch” bonding systems.
66
Acid conditioners – 35% phosphoric acid pH=0
(2)
* Most dentin bonding systems have acidic conditioners that remove the smear
layer and partially demineralize the intertubular dentin.
* Dentin without a smear layer provides a good area for micromechanical
retention.
67
Acidic primers – (HEMA) pH=2.5
do not remove smear layer. These
“self-etch” primers do not treat the dentin with 35% phosphoric
acid before bonding. They have a weaker bond, but have other
advantanges.
68
Hybrid Layer
(4)
* After the acid conditioners are applied and rinsed away,
* a hydrophilic primer or wetting agent is applied to wet the dentin and prepare
for easier penetration of the
* hydropobic resin bonding agent that can adapt to the moist dentin and co-
polymerize with the composite resin restoration.
* Most of the bond strength develops from resin penetrating and adapting to the
demineralized intertubular dentin and exposed collagen fibers. The resultant
resin interdiffusion zone is often termed the hybrid layer.
69
Resin bonding to --- can last for many years. However, the strength of resin bonding to --- has a limited life span, due to a deterioration at the hybrid layer.
enamel
dentin
70
Often, the bond of restorations that rely exclusively on resin bonding to dentin will be severely weakened after about four years. New discoveries suggest that so-called self-etch primers as opposed to so-called total etch systems (where dentin is etched with 35% phosphoric acid, before the primer/resin is applied), will have a weaker, but --- lasting bond. This may be useful when margins are on ---, and retention can be obtained mechanically, with grooves or undercuts. The primary
consideration here is longevity of seal rather than strength of bond.
The --- must still be etched with 35% phosphoric acid, with total-etch OR self-etch systems.
longer
dentin
ENAMEL
71
Adhesive bond strengths to superficial dentin are greater than those for deep dentin.
* Deep dentin =
(3)
more tubules
larger diameter of tubules
Reduced amount of intertubular dentin in deep areas
72
An important aspect of dentin bonding agents is their ability to
seal cut dentinal surfaces which reduces permeability and microleakage
73
Deep dentin more --- than
superficial dentin
permeable
74
Defensive function of the pulp
(2)
* is related to its response to irritation by mechanical, thermal, chemical, or bacterial stimuli.
* The deposition of reparative dentin by the replacement odontoblasts lining the pulp cavity acts as a protective barrier against caries and various other irritating factors.
75
Formation of reparative dentin is a continuous but slow process, taking 100 days to form a reparative dentin layer --- thick.
0.12 mm
76
In cases of severe irritation, the pulp responds by an --- reaction similar to any other soft tissue injury.
inflammatory
77
However, the inflammation may become irreversible and can result in the death of the pulp because the
confined, rigid structure of the dentin limits the inflammatory response and the ability of the pulp to recover.
78
Size of Pulp Cavity
* Decreases in size with
age.
* Younger children have larger pulps than older adults
and younger pulps are more reparative than older
pulps.
79
Pulp cavity
*It’s contour is a
miniature of the
external surface of the
tooth.
80
Reversible Pulpitis
(4)
* Many teeth have pulpal sensitivity, due to caries or following cavity preparation and restoration.
* 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 causes an increased blood flow and volume (hyperemia) and inflammation of the pulp.
* 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 reversible pulpitis and can be treated with a restoration.
81
Irreversible Pulpitis
* When pain is either spontaneous, or--if elicited by an irritant--
lingers more than 15 seconds, infection of the pulp often has
occurred and resolution by operative dentistry treatment is
usually not possible; root canal therapy is advised for this
condition termed irreversible pulpitis.
82
Pulpal Necrosis
(2)
* When this irreversible pulpitis is untreated, pulpal necrosis follows, typified by spontaneous, continuous, throbbing pain or pain elicited by heat that can be relieved by cold, and then, later, with no response to any stimulus. As inflammation and infection move beyond the root apex, the tooth may become sensitive to percussion.
* Root canal therapy is needed.
83
A primary objective during operative procedures must be
the preservation of the health of the pulp. All caries must be removed, except in the event of an indirect pulp cap, that we already discussed. Avoid overheating the dentin—as, for instance, by using a high speed handpiece without water coolant. All restorations must be well sealed.
84
Maxillary Sinusitis
Usually manifests as cold sensitivity, and sometimes spontaneous pain, in the maxillary
posterior teeth. Often hard to isolate to a single tooth.
85
Cracked Tooth
Usually manifests as cold sensitivity, or a sudden—usually unreproducible—pain when
chewing. An instrument called a Tooth Sleuth can often elicit the pain when placed
between the teeth in the central groove areas or at the tips of individual cusps.
Cracks can sometimes progress into the pulp chamber and cause pulp necrosis, or
cusps
may eventually fracture off. Cracks can sometimes be seen externally with a fiber optic
light, or it may be necessary to remove restorations to see them.
These teeth require crowning.
86
Occlusal trauma
Usually manifests as cold sensitivity, or pain in chewing. Slight tooth movements
when
the teeth are clenched and then moved from side to side may be seen, but not always.
87
Cementum
(3)
* Is slightly softer than dentin and consists of about 45% to 50% inorganic material by weight. Covers the apical root.
* It is permeable to a variety of materials.
* Light yellow and slightly lighter in color than dentin, it has the highest fluoride content of all the mineralized tissue.
88
In about ---% of teeth, enamel and cementum do not meet, and this can result in a sensitive area. Abrasion, erosion, caries, scaling, and the procedures of finishing and polishing may result in removing from the dentin its cementum covering, which can cause the dentin to be sensitive.
10
89
This must be distinguished from caries and often tooth sensitivity is caused by this
exposed dentin
90
Abrasion Lesion—Usually
--- in Form
Angular
91
Erosion Lesions are Usually More
--- in Form
Rounded
92
Another approach, if the tooth does not require a restoration to protect if
from further damage, is to treat the exposed dentin with
Glumma
Desensitizer, which we discussed previously as a dentinal tubule sealant.
Isolate with cotton and dry the tooth. Use a small applicator and rub onto
the root surface for about 30 seconds. Glumma is somewhat caustic to soft
tissue. Minimize soft tissue contact with Glumma. If it works,
desensitization may last for 2 or 3 months
93
The apical root can resorb due to ---
movement.
orthodontic
94
Tooth Contours
(2)
* The facial and lingual surfaces possess convexity that
protects and allows stimulation to gingival tissues
during mastication.
* Normal tooth contours deflect food only to the extent
that the passing food stimulates the gingival by gentle
massage rather than by irritating it. If the curvatures
are too great, the tissues usually receive inadequate
stimulation, and a potential plaque trap is created.
95
Improper contacts can result in
food impaction, producing periodontal disease, carious lesions, and possible movement of the teeth.
96
Located in the --- third of the Max and Mand central incisors.
incisal
97
Proceeding posteriorly, the contact is at the
junction of the occlusal and middle thirds which creates a larger occlusal embrasure.
98
Marginal ridges should be the same height to prevent
food impaction.
99
Proximal
contacts are
slightly
facial
to the center
of the
proximal
surface
faciolingually.
100
* Clinically, the level of the gingival attachment and the gingival sulcus is an important factor in restorative dentistry. The soft tissue health must be maintained by the teeth having correct form and position. If not, apical recession of the gingivae and possible abrasion and erosion of the roots can occur.
* The margin of the cavity preparation should, ideally, not be positioned --- (at levels between the marginal crest of the free gingival and the base of the sulcus) unless dictated by caries, previous restoration, or esthetics.
subgingivally
101
it is extremely important to not destroy --- in the restorative process. This must be preserved.
attached keratinized tissue
