Endo board review Flashcards
1
Q
What is the most common cell type of the pulp
A
fibroblasts
2
Q
what are the pulpal cell zones
A
-pulp proper -cell rich zone odontoblasts predentin dentin
3
Q
Where are the undifferentiated mesenchymal cells and what do they do
A
cell rich zone replace irreversibly damaged odontoblasts
4
Q
What are the three main types of dentin
A
Predentin secondary dentin tertiary dentin
5
Q
What is predentin
A
unmineralized dentin
6
Q
what is secondary dentin
A
dentin that is physiologically formed after root development is complete
7
Q
what are the types of tertiary dentin
A
reactionary and reparative
8
Q
what is reationary dentin
A
tertiary dentin that is produced in response to irritation by ORIGINAL odontoblasts
9
Q
what is reparative dentin
A
tertiary denting that is produced in response to irritation by recruited undifferentiated mesenchymal cells after the original odontoblasts are destroyed
10
Q
how many dentinal tubules per sq mm are at the DEJ/CEJ vs pulpal wall
A
10-25K vs 30-52K
11
Q
What are the diameter of dentinal tubules at the DEJ/CEJ vs pulpal wall
A
1-2 microns v 3-4
12
Q
What is dentin by Volume
A
45% inorganic 33% organic 22% water
13
Q
Whats the hydrodynamic theory and who proposed it
A
Brannstrom Fluid movement inside exposed dentinal tubules caused by heat, cold, air, probing, etc stimulates the A delta fibers causing dentinal hypersensitivity
14
Q
What are the afferent nerve types of the pulp
A
–A-δ: large, myelinated; quick, sharp, shooting pain; fully formed 3-5 yr post eruption –A-β: myelinated, but few in # –C: small, unmyelinated; delayed, dull, aching, or burning sensation
15
Q
What are the efferent
A
–C: sympathetic fibers – vasoconstriction
16
Q
What are the proprioceptive fibers of the pulp
A
trick question there are none
17
Q
What is the pulpal response to caries
A
Inflammatory reaction precedes bacteria “Chronic” response –Predominant cells: lymphocytes, macrophages “Acute” response – 0.5mm Edema – localized Microabscess Pressure - localized Degeneration # bacteria vs inflammatory response
18
Q
what is meant by the pathogen transition
A
Aerobic Anaerobic (facultative anaerobes obligate anaerobes)
19
Q
What does kakehashi 65 tell us
A
Abiotic mice had no issues so…No bacteria … no periapical pathosis
20
Q
Radiographic signs of additional canals
A
Sudden canal disappearance Sudden reduction in density –May represent canal division Root outline unclear –May represent additional roots Canal not centered in root
21
Q
Radiographic signs of internal resorption
A
Enlarged canal area Canal not evident through lesion Usually symmetrical Well-defined margins Stays centered on canal with change in horizontal angulation
22
Q
Radiographic signs of external resorption
A
Canal evident through lesion Usually asymmetrical Poorly-defined margins Shifts off canal with change in horizontal view
23
Q
What is our endo diagnostic goal
A
Reproduce, Alter or Eliminate the Chief Complaint
24
Q
What are the limitations of endo diagnosis
A
Diagnostic testing – imprecise Patient processing and feedback - imprecise Lack of pulpal proprioception (cannot localize) Referred pain Misdiagnosis by referring dentist
25
Do pulpal test evaluate nerve response or pulpal blood flow
nerve response,
26
What chemical do we use for cold testing
Tetrafluoroethane … -14° F
27
How should you properly cold test
“Educate” patient … why, how, what Use large, fluffy cotton pellet Establish controls Facial surface Directly on metal restorations OK?? Alternatives … ice, immersion
28
What might cause a false positive to thermal testing
–Anxiety –Gingival response –Adjacent teeth –Saliva –Periradicular response
29
what might cause a false negative response to thermal testing
–Calcified canals –Inadequate stimulus –Restorations –Immature tooth –Trauma
30
when might you use cold immersion and how?
CC not duplicated with Endo Ice Cracks, open margins, can’t localize Simulates “real-world” activity Single tooth RD isolation Establish control responses first
31
When and how to use hot immersion
Heat is primary factor of CC Cold test inconclusive Single tooth RD isolation Establish control responses first 150 F
32
What can you infer from EPT
No diagnostic value with vital pulp pathosis May defer if teeth respond to thermal test Implies only pulpal vitality or necrosis via negative nerve response A “yes or no” result … ignore the number
33
What may cause a false positive EPT
–Anxiety –Restorations –Gingival conduction
34
What may cause false negative EPT
–Inadequate contact –Immature tooth –Recent trauma
35
What are the different pulpal dx
Normal Reversible pulpitis Symptomatic irreversible pulpitis Asymptomatic irreversible pulpitis Pulpal necrosis Previously initiated therapy Previously treated
36
What are the different apical dx
Normal apical tissues Symptomatic apical periodontitis Asymptomatic apical periodontitis Acute apical abscess Chronic apical abscess Condensing osteitis
37
Symptomatic apical periodontitis
Pain - Yes Swelling - None Sinus tract - None Palpation – Maybe tender Biting – Maybe painful Percussion – normally painful Radiograph – with or without apical radiolucency
38
Asymptomatic apical periodontitis
Pain - None Swelling - None Sinus tract - None Palpation - WNL Biting - WNL Percussion - WNL Radiograph – Apical radiolucency
39
Acute Apical Abscess
Pain – Normally present Swelling – Present Sinus tract – None / maybe Palpation - Painful Biting - Painful Percussion - Painful Radiograph – WNL or apical pathology
40
Chronic apical abscess
Pain – None, maybe episodic Swelling - None Sinus tract – Present or recent Palpation – Maybe tender Biting - WNL Percussion – Maybe tender Radiograph – Apical pathology normally present
41
Condensing Osteitis
•A localized overproduction of apical bone •Apices of mandibular posterior teeth •Chronic pulpitis or pulp necrosis •A low-grade inflammation of the periradicular tissues
42
What is law of centrality
pulpal floor always located in center of tooth at level of the CEJ
43
Law of the CEJ
the CEJ is the most consistent, repeatable landmark for locating the position of pulp chamber
44
Law of concentricity
walls of pulp chamber are always concentric to external surface of tooth at level of the CEJ
45
Law of symmetry
except for max molars, orifices are equidistant from a line drawn in a MD direction through pulpal floor except for max molars; Orifices lie on a line perpendicular to a line drawn in a MD direction across center of pulpal floor
46
Who said the laws of the pulpal floor
Krasner & Rankow, JOE 2004
47
Law of color change
the color of the pulpchamber floor is always darker than walls
48
Law of orifice location
the orifices are always located at junction of walls and floor the orifices are located at angles of floor-wall junction the orifices are located at terminus of root developmental fusion lines
49
What are the canal configuration classifications
I single canal II 2 canals merge into 1 III two canals stay separate IV 1 canal splits into 2
50
How many cnals in max ant
1
51
Man ant incisor
1 canal 57 2 canals 43 1 foramen 99
52
Man canines
2 canals 22%
53
max 1st premolars
2 canals 85 3 canals 6% 2 roots 57
54
Max 2nd premolar
50/50
55
man 1st premolar
1 canal 75 2 canal 24 3 canal 1
56
man 2nd premolar
1 canal 97 2 canal 3
57
Max 1st molar MB root
1 canal 20 2 canal 77 3 canals 3
58
max 2nd molar mb root
1 canal 63 2 canal 37
59
Man 1st molar
2 canal 7 3 canal 64 4 canal 29
60
man 2nd molar
2 canals 4% 3 canals 81% 4 canals 11% C-shape 3%
61
advantages of straight line access
– Vision improved – Reduces curvature … facilitates instrumentation & obturation – Improves instrument control … fewer misadventures
62
How do you arrive at an appropriate working length?
Estimate Radiograph (0.5 – 1.0 mm) Tactile sense Electronic apex locator Paper point Patient sensation
63
Apical Foramen Position
92 % deviation of major foramina from radiographic apex 0.59mm deviation from radiographic apex
64
How does the apex locator work
“Ratio method” Simultaneously measures impedance of two different frequencies, calculates the quotient of the impedances, and expresses this quotient as a position of the file inside the root canal No calibration required
65
What are the objectives of cleaning and shaping
Total removal of contents of pulp space –Tissue, debris, bacteria, byproducts Develop straight line access to apical region Maintain central axis of canal Keep apical constriction small and in original position Continuously tapering, smooth, funnel-shaped preparation
66
Curvature complications of instrumentation
Elbow Ledge Zip (w/ or w/o perforation) Transportation Strip Perforation
67
Consequences of transportation
Incomplete debridement Difficult to obturate with good seal Incomplete healing Inability to adequately re-treat
68
Causes of transportation
Insufficient access cavity extension Poor control of file insertion length Use of end-cutting files Attempting to achieve too large a MAF size Failure to recapitulate Excessive axial (in-out) filing in a curve Insufficient irrigation Dentinal mud at apex
69
Balanced force technique
Neutralize restoring forces Maintaining centering of prep, avoiding transportation of original canal Safe-ended instrument required (Flex-R) Very efficient way to cut dentin
70
Crown-Down Philosophy
Early opening of canal for better irrigant penetration Reduce curvature, better straight-line access to apical region Reduce binding of file along full length of canal Reduce apical packing and extruding of debris
71
Results of Proper Access
Straight line access to canals Eliminates coronal canal curvature Provides “gutters” into canal Allows “blind” instrumentation Significantly improves speed Minimizes coronal file binding Allows localization of all orifices Minimizes canal transportation Improved Obturation
72
what are the fundamentals of instrumentation
Don’t force instruments / Don’t Push Files Examine files for unwinding Copious irrigation/ lubrication Recapitulate
73
Properties of niti
Extraordinary flexibility Due to very low elastic modulus Superior fracture resistance Due to ductility of the NiTi alloy Outstanding shape memory
74
disadvantages of niti
cost Altered tactile feel Requires practice to minimize problems Mandel et al IEJ 1999 Can have little or no warning prior to fracture Negotiating ledges or complicated anatomy Instrumenting abrupt curves Instrumenting canals that come together at sharp angles
75
Advantages of niti rotary
Enlarge canal that has been negotiated to length Create smooth continuous taper Reduce operator fatigue Reduce time of instrumentation
76
Types of fx
Torsional fracture Flexural fracture
77
Torsional fx
Torque load on file causes unwinding and twisting in the opposite direction Instrument is locked in the canal while the shaft continues to rotate Occurs in smaller files
78
cylic fx
Breakage occurs abruptly, with little warning No other defects visible in association with fracture Occurs more frequently in larger size files
79
Advantages of our K3 rotary system
Safe ended tip minimizes transportation ISO sizes through 60 similar to Profiles 3rd Radial Land (wide) stabilizes & keeps file centered in canal Smaller shank shortens overall length of files by 4 mm Variable Helical Flute Angle from tip to handle helps with debris removal Positive Rake Angle Variable Core Diameter+stronger tip
80
Gates glidden comparison to files size
size 1 = 50 file, 2 = 70 file
81
Peeso reemer size to file size
1=70, 2 = 90
82
Why do we need chemical shapers
All aspects of a canal system cannot be reached by files
83
gold standard of irrigation
8% (full strength) NaOCl is “gold standard” – Dissolves necrotic tissue – Removes the organic portion of smear layer – Germicide – Detoxifies endotoxins – Lubricant – Bleaching agent – Deodorizer
84
17% EDTA
– Chelating agent – Lubricant – Helps remove inorganic portion of smear layer – ethylenediaminetetracetic acid
85
CaOH
High pH ... alters environment Antimicrobial Dissolves tissue Favors calcification (alkaline phosphatase formation) Favors osteogenesis Causes limited tissue necrosis … elicits healing response Helps dry “weeping” canals Halts or slows resorptive processes Effective for 1 week
86
Goals of obturation
Replicate root canal system Maintain materials inside Tight seal to fluids, bacteria, byproducts Seal in bacteria Seal out nutrients
87
How do you disenfect gutta percha
–6 % NaOCl immersion –60 seconds
88
GP composition
Zinc oxide 56 - 75 % Gutta-percha 19 - 22 % Metal sulfates 2 - 17 % Waxes & resins 1 - 4 %
89
Roth cement composition
Powder Zinc oxide 42 % Staybelite resin 27 % Bismuth subnitrate 15 % Barium sulfate 15 % Sodium borate anhydrous 1 % Liquid Eugenol 100%
90
what did ray and trope 95 say
Good restoration significantly more important then than the technical quality of the endodontic treatment for apical periodontal health.
91
1 vs multiple visit endo
1-visit ▪ Pt unable to return ▪ Medically impaired ▪ Vital ▪ Esthetic concerns ▪ Negative per pathosis Multi-visit ▪ Canal system infection ▪ Most retreatments ▪ Acute apical symptoms ▪ Weeping canal ▪ Difficult case ▪ Sinus tract
92
Perf prognosis
▪Good – Fresh – Small – Apical / Coronal ▪Poor – Old – Large – Sulcular / Crestal
93
which type of instrument fatigue has warning signs? What are they?
Torsional – Too much apical force – Clicking sounds – Unwinding
94
Management of NaOCL extrusion
– Calm patient – Augment anesthesia – Cold compress x 6 hrs – Warm compress x 2 days – Analgesics & antibiotics – Immediate referral if airway compromise – Daily recall
95
What form of the local diffuses through the nerve sheeth
unpolarized form
96
what binds internally to Na channel site to block transmission
the ionized form
97
what controls onset time of local
low pKa faster
98
what makes local ineffective
•Low pH shifts equation to less base •Dilution by blood and fluid •Rapid absorption into circulation •Tetrodotoxin Resistance •Central Sensitization •Hyperalgesia •Allodynia
99
whats the key to success for intrapulpal injection
Backpressure, not solution
100
what did okeefe 76 say about post op pain
perop pain=post op pain
101
what is barodontalgia
Tooth pain caused by an increase or decrease in ambient pressure Usually reported by aircraft personnel and divers Tough to diagnose … pulp testing inconclusive Affects teeth with a vital pulp – defective restoration Look for etiology of chronic pulp inflammation
102
whats an enamel infraction
incomplete fracture (crack) of the enamel without loss of tooth substance
103
Whats the difference between uncomplicated and complicated fracture
pulpal involvement
104
What are the ellis classifications
Ellis Class1: enamel only Ellis Class 2: Enamel plus dentin Ellis Class 3: Enamel plus dentin plus pulp
105
What is the most commonly cracked teeth
man molars 70%
106
where do vertical root fractures begin
root and move coronally
107
What are some clinical signs of VRF
Narrow probing defect w/sinus tract at base 2 narrow probing defects on opposite sides of root Treatment: extraction
108
What are the types of luxation injuries from best to worst
Concussion Subluxation Extrusive luxation Lateral luxation Intrusive luxation
109
what are the potential sequelae of luxation injury
-pulp survival -pulp canal obliteration -pulp necrosis -marginal bone loss -resorption
110
Who are the victim of 1/2 of all dental trauma
Children
111
What is the cause of most dental trauma for kids under 1
Fall injuries
112
Possible cause of dental trauma for kids under 3
Battered child syndrome
113
Which age has the most dental injuries
8-12 Play/athletics
114
Why might teens have dental injuries
Fights
115
What are two common reasons for all ages of dental trauma
Auto injuries and fights
116
Which teeth are most commonly injured
Max anteriors
117
What are the most common types of injuries to primary teeth
Luxations/avulsions
118
What is the type of injury most common to the permanent dentition
Crown fractures
119
Steps of pt evaluation
History and Chief Complaint
Neurologic Assessment
Extraoral to Intraoral Soft / Hard Tissue injuries
Radiologic Evaluation
120
What are the classification of crown fractures
Complicated (involving the pulp)and uncomplicated (no plural involvement)
121
What radiographs are needed.
Multiple angulations recommended
* Standard periapical
* Occlusal Periapical with lateral angulations
* Mesial & Distal
* Consider soft tissue radiograph If lip or cheek laceration To search for tooth fragments
122
How should percussion be tested in a traumatic case
with finger as a mirror handle is likely to much for a pt in pain
123
Why is vitality testing important?
To have a baseline
124
Emergency Management of Uncomplicated Crown Fracture
* Seal exposed dentin
* Bond tooth fragment If available
* Composite Resin
* Glass ionomer (Vitrebond)
125
What is the incidence of Pulp necrosis in Uncomplicated Crown Fx only in enamel
.2-1%
126
What is the incidence of pulp canal obliteration in uncomplicated crown fx only in enamel
.5%
127
What is the incidence of root resorption in uncomplicated crown fx only in enamel
.2%
128
What is the incidence of Pulp necrosis in Uncomplicated Crown Fx into dentin
1-6%
129
What is the incidence of pulp canal obliteration in uncomplicated crown fx into dentin
0
130
What is the incidence of root resorption in uncomplicated crown fx into dentin
0
131
Assessing either type of crown fx
* Assessment Radiographs
* Percussion/mobility testing
* Baseline vitality testing
* Visualize Adjacent teeth
132
Treatment options for complicated crown fas
1. Pulp Capping
2. Pulpotomy
3. Pulpectomy
133
Whats the main factor for tx of complicated crown fracture
Stage of Root Maturation
Mature root -Pulpectomy
Immature root -Pulpotomy -Pulp capping
134
Pulp healing prognosis of pulp capping
71-88%
135
Pulp healing prognosis of partial pulpotomy
94-96%
136
Pulp healing prognosis of Cervical pulpotomy
72-79%
137
Preffered tx for an immature root
Partial pulpotomy (apexogenesis)
138
Average depth of inflammatory change in partial pulpotomy
less than 2 mmm
139
Types of crown-root fx
Uncomplicated and complicated
140
Emergency management of Crown to Root Fx
Radiographs
Splint fragments temporarily to alleviate pain from mastication
141
What determines the definitive tx of crown to root fx
Level of the fracture
142
Treatment modalities of uncomplicated crown to root fx
1 Fragment rem
2 restoration
143
Tx of complicated crown to root fx (restorable)
* Fragment removal
* Gingivectomy/ostectomy\*
* Endodontic therapy Post-retained crown
\*(can use orthodox extrusion/surgical extrusion instead of periodontal surgery)
144
Clinical presentation of Root Fractures
Tooth usually slightly extruded
Tooth frequently displaced lingually
Diagnosis entirely dependent upon radiographic examination
145
Radiographs for root fas
Periapical radiographs
* Standard XCP radiograph
* Increased vertical angulation
146
Emergency Management of root fx
* Reposition coronal fragment
* Flexible Splint
* -4 Weeks
* -If Fx near the cervical area - longer splinting time is beneficial Up to 4 months
147
What are the 4 types of root fx healing
1. Hard tissue 2. Conenctive tissue 3. Interposition of Bone and Connective tissue 4. Interposition of granulation tissue
148
What is the incidence of pulpal necrosis after root fx for both segments
Coronal segment - 20 to 44%
Apical segment - 0%
149
What is the incidence of pulpal obliteration after root fx for both segments
69%
150
What is the incidence of root resorption after root fx
60%
151
What is the determinant of prognosis of root fracture
Fracture location
152
Prognosis of root fx in cervical 3rd
poorer
153
Prognosis of root fx in middle and apical 3rd
better
154
Classifications of luxation injuries
1. Concussion
2. Subluxation
3. Extrusive Luxation
4. Lateral Luxation
5. Intrusive Luxation
155
Lunation injury complications
* Pulp necrosis
* Pulp canal obliteration
* Root resorption
* External
* Internal
* Loss of marginal bone support
156
Types of Ext root resorption
1. Surface resorption
2. Replacement resorption (Ankylosis)
3. Inflammatory resorption
157
Surface resorption
Superficial resorption cavities
Mainly in cementum
Complete repair of PDL
158
Replacement resorption
Direct union of bone and root
Resorption of root - replacement with bone
Direct result of loss of vital PDL
159
Inflammatory resorption
Resorption of cementum and dentin
Inflammatory reaction in the periodontal ligament
Surface resorption of cementum exposing dentinal tubules
Pulp necrosis
Toxic products from the pulp provoke an inflammatory response in the PDL
160
Internal root resorption types
1. Internal surface resorption
2. Internal replacement resorption
3. Internal inflammatory resorption
161
Internal inflammatory resorption incidence in lunated permanent teeth
2%
162
Concussion injury description
No abnormal loosening No displacement
163
Subluxation description
Abnormal Loosening No displacement
164
Emergency management of concussion and subluxation injuries
* Radiograph
* Baseline vitality testing
* Usually no splinting required 7-10 days for comfort
* Trauma Dx adjacent teeth Occlusal adjustment, if needed
* Recall
165
Pulpal necrosis incidence after concussion
3%
166
Pulp canal obliteration incidence after concussion
5%
167
Root resorption incidence after concussion
5%
168
Pulpal necrosis incidence after subluxation
6%
169
Pulp canal obliteration after subluxation
10%
170
Root resorption incidence after subluxation
2%
171
Extrusive luxation description
Partial displacement of tooth out of socket
Tooth appears elongated
Lingual deviation of crown typically
Excessively mobile
172
Emergency management of extrusive luxation
1. Radiographs
2. Baseline vitality testing
3. Anesthesia
4. Reposition tooth
5. Flexible splint 2 weeks
6. Follow-up
* 2, 4 weeks 6-8 weeks 6 months 1 year Every year for 5 years
173
Pulpal necrosis incidence after extrusive luxation
26%
174
Pulp canal obliteration incidence after extrusive luxation
45%
175
Root resorption incidence after extrusive luxation
9%
176
Lateral luxation description
Eccentric displacement of tooth
Crown usually displaced lingually
Fracture of socket wall
Tooth immobile
Percussion may have ankylotic sound
177
Emergency management of lateral luxation
* Radiographs
* PA
* Lateral
* CBCT
* Baseline vitality testing
* Usually negative results
* Anesthesia
* Reposition
* Flexible splint 4 weeks
* Add 3-4 weeks in case of marginal bone breakdown
* Occlusal adjustment, if needed
178
One week after lateral luxation
* Start endo / Ca(OH)2
* Complete within one month
* Follow-up 2 weeks 4 weeks (splint removal) 6-8 weeks 6 months 1 year Every year for 5 years
179
Incidence of pulp necrosis after lat luxation
58% (77 with closed apex)
180
Incidence of pulp canal obliteration after lat luxation
28%
181
Incidence of root resorption after lat luxation
27%
182
Incidence of loss of marginal bone support after lat luxation
5%
183
Intrusive luxation description
Displacement of the tooth into alveolar bone
Comminution or fracture of socket
Immobile with ankylotic percussion sound
184
Emergency management of Intrusive lunation
1. Radiographs
2. Pulp vitality tests Usually negative
3. Anesthesia
4. “Slightly luxate the tooth with forceps”
185
Emergency management of Intrusive lunation of teeth with incomplete root
1. Allow eruption without intervention
2. If no movement within a few weeks initiate orthodontic repositioning
3. If tooth intruded \>7mm reposition surgically or orthodontically
4. Monitor pulp vitality -if becomes necrotic Pulp regeneration or apexification
186
What may happen if deciduous tooth is intruded
May damage developing permanent tooth
187
Emergency management of Intrusive lunation of teeth with complete root
1. Allow eruption without intervention
2. If tooth intruded \<3mm If no movement within a few weeks initiate orthodontic repositioning
3. If tooth intruded \>7mm reposition surgically Pulp will be necrotic Pulpectomy 2 weeks after injury Ca(OH)2 for up to 4 weeks
188
If intruded tooth is repositioned surgically or orthodontically
Flexible Splint 2 weeks 4 weeks if displacement is ‘extensive
189
Intrusion follow up
Follow-up depends on treatment
190
Pulp necrosis and intrusion
complete root 100% Overall 85%
191
Pulp canal obliteration incidence in intrusion
10%
192
Root resorption incidence in intrusion
66%
193
Loss of marginal bone support incidence in intrusive injuries
24%
194
Graph of open apex luxation injury complications
195
Graph of closed apex luxation injury complcations
196
what makes post trauma dx difficult
Transient paresthesia in \>50%
Vital pulp may not respond to thermal or EPT!
May take 2 - 10 months to respond normally
Initial positive response may revert to negative within 2 months … usually indicates pulp necrosis
Baseline findings at time of injury important
Immature root formation improves prognosis
197
Is RCT indicated on tooth with calcific metamorphosis
NO!
198
what kind of pulp is associated with internal resorption
