Endodontics Flashcards
(148 cards)
1
Q
What are the two pain fibers in the pulp?
A
A delta and C fibers
2
Q
Which fibers are large, myelinated nerves that are found mostly in the coronal pulp?
A
A delta
3
Q
What kind of pain sensation are A delta fibers responsible for? C fibers?
A
A delta: quick, sharp, momentary pain, dissipates quickly
C fibers: dull, throbbing ache
4
Q
What pain fibers are responsible for dentinal pain?
A
A delta
5
Q
What pain fibers are responsible for pulpitis pain?
A
C fibers
6
Q
What are the conduction velocities of A delta and C fibers?
A
A delta: 2-30 m/s
C fibers: 0-2 m/s
7
Q
What are characteristics of C fibers? Where are they found?
A
small, unmyelinated nerves
found in the pulp stroma
8
Q
How are A delta fibers stimulated? How are C fibers stimulated? What is the threshold for A delta and C fibers?
A
A delta: hydrodynamics; low threshold
C fibers: direct pulp damage; high threshold
9
Q
When C fiber pain dominates, what does it signify?
A
irreversible local tissue damage
10
Q
With increasing inflammation of pulp tissues, C fibers become the only pain feature. Explain why.
A
C fiber pain occurs with tissue injury and its mediated by inflammatory mediators, vascualr changes in blood, volume and flow; increasing in tissue pressure
11
Q
What are the 6 classifications of pulpal disease?
A
- WNL
- Reversible pulpitis
- Irreversible pulpitis
- Asymptomatic Irreversible pulpitis
- Symptomatic Irreversible pulpitis
- Necrosis
12
Q
What are the possible consequences of asymptomatic irreversible pulpitis? (2)
A
- hyperplastic pulpitis
2. internal resorption
13
Q
Describe hyperplastic pulpitis. What is the proliferation attributed to?
A
Reddish cauliflower like growth of pulp tissue through and around a carious exposure.
Proliferation attributed to low grade, chronic irritation of the pulp and generous vascular supply characteristically found in young people
14
Q
What is the histological appearance of internal resorption? What is the treatment?
A
chronic inflammatory cells, multinucleated giant cells adjacent to granulation tissue, and necrotic pulp coronal to resorptive defect
Treatment is to prevent anymore damage to tooth by performing root canal therapy ASAP.
15
Q
What are characteristics of symptomatic irreversible pulpitis?
A
spontaneous, unprovoked, intermittent or continuous pain; lingering pain
16
Q
What are the potential causes of necrosis?
A
- untreated irreversible pulpitis
- trauma
- any event that causes long term interruption of blood supply
17
Q
___________________ of pulpal origin are inflammatory responses to irritants from the root canal system.
A
periradicular lesions
18
Q
What are some symptoms of periradicular disease?
A
- slight sensitivity to chewing
- feeling of tooth elongation
- intense pain
- swelling
- high fever
- Malaise
19
Q
What are the 5 classifications of periradicular disease?
A
- Acute periradicular periodontitis
- Chronic periradicular periodontits
- Acute periradicular abscess
- chronic periradicular abscess aka suppurative periradicular periodontits
- chronic focal sclerosing osteomyelitis aka condensing osteitis
20
Q
Which of the periradicular disease does this description describe?
painful inflammation around the apex
A
acute periradicular periodontitis
21
Q
acute periradicular periodontitis can be a result of what 3 events?
A
- extension of pulpal disease into periradicular tissue
- canal instrumentation and overfill
- occlusal trauma such as bruxism
22
Q
Which of the periradicular disease does this description describe?
acute abscess, painful and purulent around the apex
the result of exacerbation of acute apical periodontitis from a necrotic pulp.
A
acute apical abscess
23
Q
What radiograph characteristics do you find for acute apical abscess? Clinical characteristics?
A
Clinical: oral swelling only
Radiograph: relatively normal or slightly thickened lamina dura due to infection spreading rapidly beyond the confines of the cortical plate before demineralization can be detected radiographically
24
Q
What kind of lesion is resulting from an infection and rapid tissue destruction arising from within chronic periradicular periodontitis ?
A
Phoenix abscess
25
What are the symptoms of phoenix abscess?
same as acute apical abscess
26
How can you tell the difference between a phoenix abscess and an acute apical abscess?
With phoenix you can see a periradicular radiolucency.
27
What are histo features of acute apical abscess?
Liquefaction necrosis containing neutrophils and other cellular debris; surrounded by macrophages and occasional lymphocytes and plasma cells. Bacteria are not always found at the apical tissues or within abscess cavity
28
What are the presenting signs and symptoms of acute apical abscess?
1. rapid onset and swelling
2. mod to severe pain
3. pain with percussion and palpation
4. slight increase in tooth mobility
5. usually swelling remains localized however the infection may spread and diffuse widely becoming cellulitis
29
What periradicular diagnosis is the following: long standing, asymptomatic, asymptomatic or mildy asymptomatic lesion
Chronic periradicular periodontitis
30
What is the procedure you do to confirm if a tooth needs endo treatment or not especially in cases where this acute periradicular periodontitis occurs around both vital and non vital teeth?
Temperature testing
31
What do radiographs typically reveal for acute periradicular periodontitis?
Lamina dura may look slightly wider or the same
| Tooth may be painful during percussion.
32
Which of the periradicular disease does this description describe? Long standing asymptomatic or mildy symptomatic lesion. May have slight tenderness to percussion.
chronic periradicular peridontitis
33
What does chronic periradicular peridontitis look like radiographically?
Typically find a RL lesion at apex
34
Diagnosis of chronic periradicular peridontitis is confirmed with these 3 things:
1. general absence of symptoms
2. radiographic presence of periradicular RL
3. confirmation of pulpal necrosis
35
Which of the periradicular disease does this description describe? Associated with either a continuously or intermittently draining sinus tract without discomfort; the exudate can also drain through the gingival sulcus mimicking a "pocket. "
Chronic periradicular abscess
36
What are the clinical evidence of chronic periradicular abscess?
1. draining sinus
2. pulp test negative
3. bone loss in periradicular area confirmed via radiograph
37
Which of the periradicular disease does this description describe? Excessive bone remineralization around apex asymptomatic, vital tooth?
Condensing osteitis
38
Why is there an increase in radiopacity for condensing osteitis?
chronic low grade inflammation
39
Treatment for condensing osteitis?
No need for root canal therapy
40
What are the only systemic considerations that contraindicate endo therapy?
1. diabetes
| 2. MI in the past 6 months
41
When does it become easy for patients to determine location of pain? Why is it difficult for patients to locate pain if the inflammatory process does not reach the PDL?
When the inflammatory process reaches or effects the PDL.
If the inflammatory process only stays in the pulp, the pulp only has fibers that transmits pain and not location of pain. The PDL has proprioceptive fibers.
42
Pain from posterior teeth may be referred to where?
preauricular area, down the neck or up to the temple on the ipsilateral side
43
Where do maxillary molars refer pain to typically?
zygomatic, parietal, occipital regions of the head
44
Where do mandibular molars refer pain typically?
ear, angle of jaw, posterior regions of the neck
45
Where is the response coming from if a patient complains of dull, drawing or aching?
bone
46
Where is the response coming from if a patient complains of throbbing, pounding, pulsating?
vascular
47
Where is the response coming from if a patient complains of sharp, electric, recurrent, stabbing
nerve
48
What are characteristics of pulpal and periradicular pathoses?
aching, pulsing, throbbing, dull, gnawing, radiating, flashing, stabbing, or jolting pain
49
What does a percussion test tell us?
Indicates the presence of inflammation of the PDL and the extent of the inflammatory process
50
What are some OTHER factors that may cause percussive responses?
1. rapid ortho movement
2. hyperocclusion
3. lateral periodontal abscess
51
When are thermal tests especially valuable?
When their pain is considered diffuse, helps pinpoint the source.
52
When conducting a thermal test, the patient does not respond to stimulus, what does this mean?
Necrotic pulp or a false negative from either an immature apex, excessive calcification or recent truama
53
When conducting a thermal test, the patient responds mild to moderate awareness of slight pain and subsides within 1-2 sec?
WNL
54
When conducting a thermal test, the patient responds with strong, momentary response that subsides 1-2 secs
Reversible pulpitis
55
When conducting a thermal test, the patient responds with moderate to strong painful response that lingers for several seconds longer after the stimulus have been removed
Irreversible pulpitis
56
When do you not use an electric pulp testing technique?
A patient with a pacemaker
57
During a radiographic exam for possibly an endo lesion what do you want to conduct?
involves exposure of two films at the same vertical angle with with a 10-15 degree change in horizontal angulation
58
What is the SLOB rule?
to determine which object is closer to the buccal surface; the object closer to the buccal surface appears to move in the direction opposite the movement of the tube.
Same
Lingual
Opposite
Buccal
59
What are the differentials when seeing a RL lesion?
1. Vertical root fracture
2. Lateral periodontal cyst
3. Osteomyelitis
4. Developmental cysts
5. Traumatic bone cyst
6. Ameloblastoma
7. Cemental dysplasia
8. Cementoblastoma
9. Severe hypercementosis / condensing osteitis
10. Central giant cell granuloma
60
What are 2 other nonanatomic RL?
odontogenic and nonodontogenic
61
List a few odontogenic RL
dental papilla, dentigerous cyst, OKC, odontoma
62
List a few non-odontogenic RL
fibro-osseous lesion, osteoblastoma, cementifying fibroma, ossifying fibroma, malignant tumor, multiple myeloma
63
Where does cracked tooth syndrome typically occur?
Lower posterior molars especially first molars
64
What is cracked tooth syndrome?
1. sustained pain during biting pressure
2. pain only on releasing pressure
3. occasional, momentary, sharp, poorly localized pain during mastication, very difficult to reproduce
4. sensitivity to thermal changes
5. sensitivity to mild stim such as sweet/acidic foods
65
What is the treatment for a cracked tooth with healthy pulp or reversible pulpitis?
Splint with ortho band and observe or prepare for a crown (place a sound, temp crown and observe before placing a permanent crown).
66
What is the treatment for a cracked tooth with irreversible pulpitis or necrosis with acute periradicular periodontitis?
1. Endo tx
2. Restoration options:
a) With sufficient tooth structure: place a glass ionomer or acid etch dentin bonded core W/O post and restore with permanent crown. Core can be placed 2-3 mm in the the canal orifices.
b) With insufficient tooth structure: Place a post passively along with an acid-etched, dentin bonded core and a permanent crown with margins of 2mm or more of cound tooth structure. Crown lengthening and/or extrusion max be necessary.
67
What are the prognoses of tooth fractures:
a) presence and extent of an isolated probing
b) crack to the floor of the pulp chamber
c) fracture all the way from mesial to distal
a) guarded prognosis
b) guarded prognosis
c) poor prognosis
68
Where do vertical root fractures occur on teeth?
Buccal to lingual plane of roots
69
What are the clinical signs of vertical root fractures?
1. isolated probing
2. RL from apical to mid root (J shaped)
3. May mimic other entities such as perio disease or failed root canal tx
70
How do you confirm or verify a vertical root fracture and make a diagnosis?
Make a flap to visualize fracture
71
What are two general treatments to vertical fractures?
1. Extraction of single rooted tooth
| 2. Hemisection of multirooted tooth: remove only affected tooth
72
T or F
Endo disease can cause perio disease but perio disease typically doesnt cause endo disease unless if perio disease extends to the apices
True
73
T or F
| Perio tx has NO affect on pulpal health
False, because perio tx such as SRP can result in bacterial penetration into exposed dentinal tubules, which can cause thermal sensitivity and subsequent pulpitis
74
Describe the differences between primary endo lesions vs perio lesions
Endo lesions: Inflammatory processes may or may not be localized the the apex;may appear on the lateral aspects of the root or in the furcation or sinus tract; tooth test is NOT VITAL
Tx: endo
Perio lesions: lesion is progressive, starts in sulcus and migrates apically as deposits of calculus and plaque produce inflammation that causes loss of surrounding bone and soft tissues. Broad bases pocket formation. Teeth are VITAL.
tx: SRP
75
What is the treatment of primary perio lesions with secondary endo involvement?
Endo therapy following SRP
76
What is the treatment of primary perio lesions with secondary endo involvement? aka True combined lesion
Requires both perio and endo tx.
| Prognosis depends on the severity of perio in these teeth
77
Explain file dimensions: D0, D16, Taper. How to calculate D16.
D0: the file size at the tip of the file
ie 8 file @ D0= 0.08mm; 15 file @D0=.15 mm etc
D16: the file size at the end of cutting flutes end
Taper: the amount a file diameter increases each mm from tip to end of cutting flutes
Calculation: D0 + (taper x 16) = D16
78
What does NaOCl do? What happens with NaOCl accident? Tx?
```
Disinfects canals (antimicrobial)
dissolves organic matter but does not remove smear layer
lubricant
```
Causes a patient to experience instant extreme pain, excessive bleeding from tooth, rapid swelling, rapid spread of erythema, later bruising and sensory and motor nerve deficits.
Tx: Long lasting anesthetic, encourage drainage, steroids, cold compresses, antibiotics, analgesics, daily follow up
79
What does EDTA do? (ethylenediaminetetraacetic acid 17%)
Removes inorganic material (smear layer)
80
What does CaOH do?
it is an intracanal medicament; it's the best available due to its high pH (12.5) its able to kill the bacteria; inactivates their LPS and has tissue dissolving capacity
81
List surgical endo procedures? (7)
1. I&D (soft tissue), trephination (I&D in bone)
2. Root end resection (apicoectomy)
3. Hemisection
4. Bicuspidization
5. Root amputation
6. Intentional replantation
7. Surgical removal of the apical segment of fractured root
82
What is the best treatment for acute apical abscess?
I&D, endo therapy
83
When do you perform apicoectomy (root end resection)?
When there is a persistent or enlarging periradicular pathosis following nonsurgical endo tx
84
When do you perform a hemisection? This procedure is common with what tooth?
To remove defective root of multirooted tooth and RCT on all remaining roots.
Common with mandibular molars
85
True or False. It is preferable to complete the root canal treatment and place a permanent restoration into the canal orifices prior to hemisection.
True
86
What is bicuspidization?
The complete separation of two roots of mutlirooted tooth.
87
What is root resection?
Root amputation only, keep crown. Must have an existing fixed prosthesis with at least one root structurally sound.
88
What is intentional replantation? When is it indicated?
The insertion of a tooth into its alveolus after the tooth has been extracted for the purpose of accomplishing a root end filling technique.
Indicated when non surgical therapy does not work and periradicular surgery is not possible due to high degree of risk to anatomical structures; the tooth has acceptable periodontal status prior to replantation procedure
89
When do you perform surgical removal of an apical segment of a fractured tooth?
When coronal segment is restorable and functional and when one of the following clinical situations present: root fracture in apical portion of root and pulpal necrosis in the apical segment as indicated in periradicular lesion or clinical signs or symptoms.
90
True or False
Pulpotomy provides the greatest pain relief but pulpectomy is usually effective in the absence of percussion sensitivity.
False. Pulpectomy provides the greatest pain relief when it comes to temporary fixes. Pulpotomy typically do the trick IF there in no percussion sensitivity.
91
How are rubber dams sterilized?
Submerged in glutaraldehyde solution for 24 hours (cold sterilization); used for heat and cold labile instruments; should only be used for heat sensitive instruments
Note: will not kill all organisms
92
What are the parameters for pressure sterilization?
Instruments wrapped and autoclaved for 20 min at 121C and 15 psi; able to kill bacteria, spores, viruses
93
What are the consequences of instruments after multiple sterilizations?
It become dull due to contraction and expansion movement from extreme changes in temp.
94
What is the superior sterilization technique for sharp edged instruments?
Dry heat sterilization
95
Protocol for dry heat sterilization?
160C for 60 min
| Note if the temp goes below 160 C then the whole cycle has tot start over.
96
When obtaining diagnostic radiographs what are the three techniques for accurate angulation?
1. Paralleling tech
2. Modified paralleling tech (used when unable to get parallel to teeth.
3. Bisecting angle tech. (least accurate)
97
What is the difference between D and E films in radiography?
```
D film (ultraspeed)- slightly better contrast
E film/Ektaspeed plus- produces similar quality to D but requires only half of the radiation
```
98
What is the optimal setting for max contrast between RO and RL structures?
70 kV
99
what does increasing Kvp do?
Reduces radiation dose to skin, needs to be 70 or higher
100
what is the max radiation dose/person/yr?
50 microsieverts
101
What bacteria predominate in primary endo infections?List gram (-) and (+) bacterium
Strictly anaerobes
Gram (-): porphymonas, bacterioides melaninogenica (two most common in endo infections)
Gram (+): actinomyces (from root caries)
102
What bacteria predominates in unsuccessful endo therapy?
Enterococcus faecalis (faculative anaerobe)
103
what antibiotics are used in endo? Explain what each ABX are used for.
#1 Pen VK- most strict anaerobes and gram (+) faculative anaerobes
2. Clindamycin- effective against gram (-) and gram (+) bacteria including both strict and faculative anaerobes
3. Metronidazole- effective against strict anaerobes but not faculative anaerobes or aerobes
104
List some strict anaerobes found in root canal infection?
porphymonas, prevotella, peptostreptococcus, fusobacterium, actinomyces
105
List some gram (+) faculative anaerobes found in root canal infection
streptococci and enterococci
106
For traumatized teeth or emergencies, how often should you repeat the pulp vitality test? What is the purpose?
Should be repeated at 3 weeks, 3 months, 6 months, 12 months and yearly intervals.
Purpose is to establish a trend of physiologic status of pulp
107
Define ellis class 1 fracture.
Infraction which means incomplete crack of enamel without loss of tooth structure
108
Define ellis class 2 fracture.
Crown fracture (involving enamel and dentin only) without pulp involvement
109
Define ellis class 3 fracture.
A complicated fracture that involves enamel, dentin, and pulp.
110
Define ellis class 4 fracture.
A tooth that was traumatized and have become non-vitalized with or w/o tooth loss
111
Define ellis class 5 fracture.
Luxation, where the tooth tends to dislocate tooth from the alveolus
112
Define ellis class 6 fracture.
Avulsion: complete separation of tooth from alveolus by trauma
113
True or false.
| With immature teeth, you want to always try to perform vital pulp therapy first before RCT.
True
114
What is the risk for a pulp exposed from trauma injury for more than 24 hours?
High risk for bacterial contamination
115
What is the most common characteristic of root fractures?
Oblique fractures (facial to palatal)
116
When taking radiographs for a root fracture, what is the protocol?
Radiographs should include 1 occlusal film and 3 PAs (1 at 0 degrees, + 15/-15 degrees from vertical axis of tooth)
117
What are the 4 healing patterns of root fractures?
1. Healing with calcified tissue at fracture site: most ideal
2. Healing with interproximal connective tissue
3. Helaing with bone and connective tisssue
4. Interproximal inflammatory tissue without healing (worst)
118
Coronal root fracture
Prognosis?
Tx?
Prognosis: poor especially if the fracture was at the level of or coronal to the crest of alveolar bone
Tx: stabilize coronal aspect with rigid splint for 6-12 weeks; if coronal segment does not reattach then extract coronal segment and may be able to perform ortho extrusion or crown lengthening
119
Midroot Fracture
Prognosis: pulp necrosis occurs in 25% of root fractures (mostly limited to coronal segment), this may lead to apexification when the pulp lumen is wide at the apical extent
Tx: stabilize for 3 weeks
120
Apical fracture
Prognosis: horizontal root fx at the apex is the best prognosis of all other types due to most of the pulp vital and and have little to no mobility
121
Which is better to have, vertical or horizontal root fracture?
Horizontal
122
Is oblique fracture or transverse fracture more preferable?
Oblique
123
What are considered complicated fractures?
Ellis class 3-6
124
What are luxation type injuries?
```
Concussion
Subluxation
Extrusive luxation
Lateral luxation
Intrusive luxation
```
125
Define concussion.
No displacement, normal mobility, sensitive to percussion; responds to pulp test; pulp blood supply is likely to recover
126
Tx of concussion
baseline vitality testing and radiographs, occlusal adjustment, no immediate treatment needed (let tooth rest, avoid bite and then follow up)
127
Define subluxation
the tooth is loosened but not displaced
128
Subluxation tx
Baseline vitality tests and radiographs; occlusal adjustment, splint for 3 weeks if mobile
129
What are pulpal outcomes for subluxation injuries?
6% rate of pulpal necrosis with closed apices
| 0% rate of pulpal necrosis with open apices
130
Define extrusive and lateral luxation
The tooth is partially extruded from its socket; sometimes accompanied with alveolar fracture
131
What is lateral extrusion?
When the crown of tooth is displaced palatally and root apex labially, can fracture alveolar bone
132
What is the treatment of lateral and extrusive luxation?
radiographs, reposition teeth, physiologic splint, endo tx if necessary or observe revascularization if open apices; no vitality testing due to possible false negative
133
What are the pulp outcomes for closed apices in extrusive, lateral and intrusive luxation?
```
Pulpal necrosis rates:
Extrusive luxation (65%) > Lateral luxation (80%) > Intrusive luxation (96%)
```
134
Define intrusive luxation.
The tooth is apically displaced
135
Intrusive luxation tx
With immature teeth (open apices), just allow for tooth to re-erupt
With mature teeth, closed apices:
orthodontic reposition, surgical reposition, endo tx
136
What is avulsion?
a complete separation of tooth from alveolus
137
What is the number one priority for avulsion?
protect viability of PDL
138
How do you protect the viability of PDL after avulsion?
Reimplant tooth in socket immediately to improve PDL healing and prevent root resorption
If reimplantation is not possible, place tooth in storage medium.
139
List the best mediums to worst.
Viaspan > Hank's Balanced Salt Solution > Milk > Saline > Saliva > Water
140
List the success rate for the following extra alveolar dry times:
<15 min
30 min
>60 min
<15 min = 90%
30 min = 50%
>60 min = <10%
141
What is the tx plan when a closed apex tooth is avulsed and its been out of the mouth for longer than 60 min? What ABX do you administer for this situation?
1. remove debris and necrotic PDL
2. remove coagulum from socket with saline
3. immerse tooth in a 2.4% sodium fluoride solution with a pH of 5.5 for 5 min
4. Replant tooth
5. Stabilize with semirigid splint for 7-10 days
6. ABX
7. Tetanus booster with physician
ABX:
penicillin 4x/day for 7 days
doxycycline 2/day for 7 days
142
What is the tx plan when a open apex tooth is avulsed and its been out of the mouth for less than 60 min?
1. if contaminated, clean the root and apical foramen with saline
2. place tooth in doxycycline
3. remove coagulum from socket with saline
4. Replant slowly
5. Stabilize with semirigid slpint for 7 days
6. ABX
penicillin 4x/day for 7 days
doxycycline 2/day for 7 days
7. Tetanus booster with physician
143
What is the tx plan when a open apex tooth is avulsed and its been out of the mouth for more than 60 min?
Replantation is not indicated!
144
Post reimplantation of avulsed tooth should have RCT completed when?
7-10 days post reimplantation
145
What is the consequence of delaying RCT in a reimplanted closed apices avulsed tooth?
Root resorption
| Need to undergo long term CaOH treatment before RCT can occur
146
What is the consequence of delaying RCT in a reimplanted open apices avulsed tooth?
Nothing. You should avoid RCT on immature teeth with open apices. If there is any sign of infection, apexification should start immediately
147
What is the treatment plan of a avulsed tooth with closed apices that was out of the mouth for greater than 60min after reimplantation?
Endo tx 7-10 days after or if delayed and resorption occurs begin long term CaOH tx
148
What is the treatment plan of a avulsed tooth with open apices that was out of the mouth for greater than 60min after reimplantation?
If endo was not completed out of mouth then you need to start apexification ASAP
