Endodontics Flashcards
(92 cards)
1
Q
function and use of NaOCl (sodium Hypochlorite)
A
irrigant used during cleaning and shaping
tissue solvent with antimicrobial effect
typically used at 5.25%w
2
Q
hydrogen peroxide function and use
A
used for canal irrigation
antimicrobial and effervescent effect (bubbling out debris)
3%
3
Q
EDTA function and use
A
used to remove calcium, dimineralize and soften dentin, remove smear layer
chelating agent with antimicrobial effect
4
Q
what is a chelating agent
A
agent with the ability to comine with metalls ion and thereby inactivate it
5
Q
Chlorhexadine
A
intracanal cleansing agent
substantivity
6
Q
why should chlorhexadine and NaOCl not be placed in the canal simultaneously
A
because it forms a precipitate that can block the canal
7
Q
What is placed in a sealer to make it radioopaque
A
metallic salts
8
Q
calcium hydroxide (CaOH) use and function
A
placed in the canal as antibacterial agent,
placed between appointments
increases pH in the canal
9
Q
gutta percha contents
A
59-75% zinc oxide
19-22% gutta percha
1-17% metal sulfates
1-4% plasticizing wax and resin
10
Q
Mineral Trioxide Aggregate (MTA) uses and function
A
cement like material used as root end filling, perforation repair, and pulp capping
11
Q
Iodine Potassium Iodide uses and function
A
intracanal medicament/irrigant
antimicrobial action with little toxicity or irritation
12
Q
Eugenol and eucalyptol uses and function
A
intracanal medicaments
13
Q
lubricants function
A
decreases friction, decrease risk of file separation
14
Q
How should reamers be rotated
A
no more that 1/2 turn at a time
15
Q
D type files
A
rhomboid bland alternating large and small flutes
16
Q
rubber dam function
A
- prevent irrigants from aspiration
- prevents aspiration of files and such
- prevent bacterial contamination
17
Q
H type (Hedstrom)
A
spiral edges like a screw, cuts only on pulling stroke
18
Q
K type
A
tightly spiraled, cuts on push, pull, rotation
19
Q
NiTi (Nickle titanium)
A
elastic nickle titanium
20
Q
What colors are the files (by size)
A
#10 purple #15 White #20 Yellow #25 Red #30 Blue #35 Green #40 Black
21
Q
Objectives of Access Preparation
A
- Straight line access (prevent ledging, stripping, perforation)
- Preservation of tooth structure
- Unroofing pulp chamber to expose canal orifices
22
Q
Maxillary central incisor access and canal
A
triangular (from lingual)
canal is large, conical and confluent with pulp chamber
23
Q
Maxillary lateral incisor access and canal
A
triangular (from lingual)
smaller than central, concical
root tip is palatal or distal
24
Q
Maxillary canine access and canal
A
canal is larger than max incisors, oval in shape
Wider BL than MD
rarely has divided canal at apex
25
Max 1st premolar access and canal
generally has 2 roots and 2 canals (palatal is larger) sometimes merge
Access is oval in shape (wider BL than MD)
26
Max 2nd premolar access and canal
Access is oval in shape (wider BL than MD)
60% have 1 canal (40% 2 canals)
typically 1 root
27
Maxillary Molars
Access in Triangular in shape (maintain oblique ridge)
3-4 canals (MB, P, DB, MB2)
P canal is straight, wide, tapered
DB is small and tapered
MB smallest, splits into 2 canals, difficult
28
Mandibular Incisors
Access circular in shape
| single canal that may divide into B and L canals
29
Mandibular Canine
Access is oval (wider BL than MD)
| common to have canal separate into 2
30
Mandibular premolars
Access is oval (Wider BL than MD)
| cone shaped canal (70-80% have single canal)
31
Mandibular Molars
Access is blunted triangle (apex at D)
typically 3 canals (ML, MB, D) 4 canals = DL, DB
D canal is bisector of ML and MB
32
How to determine Working Length
1. Select Stable reference point
2. estimate with #10 or #15 hand file and X-Ray
2. Use apex locator on #10 or #15 File and X-Ray
3. correct X-ray discrepancy
4. 1 mm short of radiographic apex
33
goals of instrumentation
1. removal of pulpal tissue
2. remove infected dentin (houses bacteria)
3. Shape canal
34
What are the two ways canals are cleaned
biomechanical
| Chemomechanical
35
What is the crown down technique
early flaring with rotary instruments
incremental removal of canals debris from orifice to apex
files used in a large to small sequence
Coronal portion cleaned and shaped before apical portion
36
What is the step back technizque
use smaller flexible files in the apical third
use sequentially larger files at incremental lengths
stay .5-1mm short of WL
apical portion prepared before coronal portion
37
gutta percha properties
flexible at room temp, plastic at 60 degrees C (140 F)
opaque (barium salts)
soluble in chloroform, ether, xylol
38
Lateral compaction technique
master apical cone selected at 1mm short of apex
walls coated with sealer
cone compacted against wall, another cone placed and compacted until canal is filled
39
warm vertical compaction
master cone selected, walls coated with sealer
cone pushed in and cut with hot instrument
hot instruement placed halfway down the canal melting apical gutta percha
condenser pushes GP apically
repeat until obturated
40
chloropercha technique
same technique as warm vertical compaction except chloroform is used to make GP plastic
41
Carrier based obturation
sealer is placed in the canal
| warm coated GP is placed into the canal
42
continuous wave compaction
warm vertical compaction performed with a tip heated electrical plugger
43
problems with silver point obturation
post and core buildups became impossible
apical surgery is complicated
may cause inflammatory root resorption
44
should we remove asymptomatic, non problem causing silver points
nope
45
When to do surgical endodontics
```
obstructed canal
wide apex
inaccesible canal
persistant apical periodontitis in well filled canal
internal or external root resorption
post and core in tooth
```
46
Root amputation or apioectomy
flap, bone removed, apex removed,
| area curetted, retrograde filling
47
retrograde amalagam or MTA filling
apioectomy, followed by opening of apex and filling with MTA or amalgam
Used when retrograde filling isn't likely to succeed
48
I&D and trephination
cleaning to relieve pressure and give the infection a path to drain
49
Hemisection
multirooted tooth cut vertically in half, defective half of the tooth is EXTd, RCT on the remaining half
(makes two teeth, EXT bad one)
50
Root amputation
removing infected root, leave entire crown
51
Intentional reimplantation
EXT tooth, perform RCT outside of mouth, Reimplant
| poor prognosis
52
Preventing ledging
(straighter canals)
straight line access
good lubrication
flexible files
53
Ledging Treatment
relocate and renogotiate canal to WL (reverify) then filled and sealed
if ledge isnt removed
instrument to new WL, fill and seal (inform pt)
54
signs of perforation
```
sudden hemorrhage
sudden pain
radiograph
apex locator not functioning right
deviant file course
severe post op pain
```
55
better prognosis of tooth with perforation if
```
its located above bone
smaller than 1 mm
occurs later in treatment
easily accessable and treated
good isolation
well sealed after repair
```
56
Perforation treatment
```
repair with MTA
extrusion and restoration
crown lengthening and restoration
root amputation or hemisection
intentional reimplantation
```
57
prevention of instrument separation
```
use of the right instrument
adequate lubrication and irrigation
examine instruments for fatigue
replace files often
dont use larger files until small files don't bind
```
58
treating canals with separated files
remove instrument if accessable and loose
navagate around the instrument, leave it there
prepare and instument to WL above separated file (needs adequate seal)
59
prognosis of tooth with separated file better if...
minimal debris apical to file
separation occurs later in procedure
larger size file
60
Causes of Vertical Root fracture
excessive filling or condensation forces
wedge effect during post cementation
over preparation of the canal (thin dentin/cementum)
61
Symptoms of Vertical Root Fracture
serve perio pocketing
sinus tract development
pain with chewing
lateral root radiolucencies
62
Treatment of vertical root fracture
EXT of single rooted tooth
| root amputation if possible (multi rooted tooth)
63
complicated vs uncomplicated fractures
complicated include the pulp, uncomplicated do not
64
Complicated fracture treatments
```
pulp capping (young teeth, pinpoint exposure, 1 hr or less)
partial pulpotomy (young teeth, large exposure, less than 24 hours, vital pulp)
pulpectomy (permanent teeth, large exposure, pain, long exposure)
```
65
Root fracture prognosis is good if
fracture is in apical third of root
low mobility
tooth is vital
66
root fracture treatment
splint tooth 4 weeks, take out of occlusion
PDL heals the fracture
vital tooth = granulation tissue, then calcified tissue
RCT if pulp necrosis occurs
67
Alveolar fracture diagnosis
mobility of multiple teeth
occlusal discrepency
radiograph or CT
68
alveolar fracture treatment
reposition bony segment splinted for 4 weeks
| monitor teeth for vitality
69
concussion definition
injury to tooth causing tenderness to percussion
no displacement or mobility
good prognosis
70
subluxation
tender to percussion
slighlty mobile but not displaced
good prognosis
may need stabilization
71
extrusive luxation
teeth displaced incisally
typically mobile
tender to percussion
72
extrusive luxation treatment
```
cleanse area with saline
reposition tooth
suture gingiva
splint for 2 weeks
monitor vitality
```
73
lateral luxation
toot displaced laterally
usually fracture of facial cortical bone
sensitive to percussion
fracture is palpatable
74
lateral luxation treatment
```
cleanse area with saline
reposition tooth
suture gingiva
splint for 2 weeks (4 or more in severe cases)
monitor vitality
```
75
Intrusive luxation
displacement apically
tender to palpation and percussion
may intrude into sinus or nasal cavity
76
intrusive luxation treatment
incomplete root formation and less than 7mm of intrusion = allow re-eruption
complete root formation of greater than 7mm intrusion = surgical or orthodontic intervention
77
Avulsion
complete separation from the socket
| may have alveolar fracture
78
avulsion antibiotic treatment
prescribe amoxicillin to 12 and under 7 days
prescribe doxycycline to 12 and older 7 days
if tooth touched soil recommend tetanus booster
79
post implantation instructions
soft diet for 2 weeks
no contact sports for 2 weeks
brush teeth with soft brush after each meal
rinse with .12% Chlorhexadine 2x per day for 2 weeks
80
avulsed tooth with closed apex already reimplanted
Rinse, radio, flexible splint
81
avulsed tooth with closed apex kept in medium <60 min:
clean, irrigate, radiograph, anesthetize, reimplant, radiograph, flexible splint
82
avulsed tooth with closed apex dry for > 60 min
remove necrotic tissue with gauze
soak in NaF 20 min
irrigate, radiograph, reimplant, radiograph, suture if needed, flexible splint (Endo prior if needed)
83
avulsed tooth with open apex already reimplanted
rinse, radiograph, flexible splint
84
avulsed tooth with open apex, in biological medium for < 60 min
clean, soak in doxycycline, irrigate, radiograph, anesthetize, reimplant, radiograph, flexible splint
85
avulsed tooth with open apex stored dry for > 60 min
remove necrotic tissue with gauze
| irrigate, radiograph, RCT (apexification), reimplant, radiograph, flexible splint
86
External Resorption vs. inflammatory external resorption
external resorption from trauma, not bacterial in etiology
| inflammatory ER = necrosis -> bacterial toxins leave -> ER
87
Replacement External resorption
ankylosis - PDL replaced with bone
88
internal resorption
inflammatory process, symmetrical RL in root canal, pulp may be vital or necrotic
Treat with prompt RCT
89
components of pulp
```
odontoblasts
fibroblasts
nerves
blood vessels
lymphatics
```
90
Pulpotomy
What
When
removal of the coronal portion of the tooth
| in immature teeth, vital pulp
91
apexogensis
immature teeth, open apex, damaged coronal pulp but healthy radicular pulp.
after pulp capping or pulpotomy in immature teeth
hope that completion of the root happens so you have an apical stop for RCT
92
apexification
done on necrotic teeth with open apex
| placement of CaOH or MTA in the apical third to foster completion of root formation
