Endodontics Flashcards Preview

NBDE II Board Busters > Endodontics > Flashcards

Flashcards in Endodontics Deck (254):
1

4 ways to dx vertical root fracture

-transillumination
-wedge and x-ray
-perio defect
-tooth slooth

2

vertical fracture through ROOT has __ prognosis unless you can remove the segment and ___ and ___ are performed

HOPELESS prognosis unless GINGIVOPLASTY and ALVEOLOPLASTY

3

tooth with vertical root fracture has ___ prognosis

POOR prognosis

4

most vertical root fractures are caused by?

using too much CONDENSATION FORCE during OBTURATION

5

anterior tooth fractures are usually caused by

accidental trauma

6

cracked tooth syndrome is characterized by

sharp, brief pain occurring unexpectedly when pt is chewing

7

3 types of flaps

1. submarginal curved (semilunar)
2. submarginal triangular and rectangular (ochsenbein-leubke)
3. full mucoperiosteal (full thickness)

8

submarginal curved flap (semilunar)

half moon shaped, curved horizontal incision in mucosa or attached gingiva with concavity towards apex

NOT for anterior tooth root-end surgery

9

disadvantages of submarginal curved flap (semilunar) (4)

1. limited access and visibility
2. tearing of incision corners
3. incision over bony defect -> scars
4. incision limited by attachments (frenum muscles)

10

submarginal triangular and rectangular flap (ochsenbein-leubke)

requires 4 mm attached gingiva, healthy periodontium

scalloped incision in attached gingiva with 1 or 2 vertical incisions

LESS risk of incising over bony defects
no post-surgery gingival recession

CAN be indicated for root end surgery on anterior tooth

11

disadvantages of submarginal triangular and rectangular flap (O-L)

hemorrhage and scarring

12

advantages of submarginal triangular and rectangular flap (O-L)

better access and visibility > semilunar flap

NOT better than full mucoperiosteal flap

13

full mucoperiosteal (full thickness)

allows max. access and visibility

raised from gingival sulcus (elevating gingival crest + interdental gingiva)

outline precludes incisions over bony defects -> allows perio tx (curettage, SRP, bone re-shaping)

CAN be indicated for root-end surgery on anterior teeth

14

disadvantage of full thickness flap

difficult to reposition, suture, alter

gingival recession possible

15

electric pulp tester has HIGHER current if

tooth has CHRONIC PULPITIS

16

EPT checks vitality by

stimulating nerve endings with a LOW CURRENT and HIGH POTENTIAL DIFFERENCE in voltage

17

EPT results
1. acute pulpitis = ___ current
2. chronic pulpitis = ___ current
3. hyperemia = ___ current
4. pulp necrosis/abscess = ___ current

1. acute = LOWER than normal (acute inflammation lowers pain threshold)

2. chronic = HIGHER than normal

3. hyperemia = LOWER than normal, but HIGHER than (1) acute pulpitis

4. necrosis/abscess = NO response

18

EPT gives false (+) in these circumstances

1. pus-filled canal
2. nervous pt

19

EPT gives false (-) in these circumstances

1. recent trauma
2. insulating restoration
3. gloves

20

EPT also not reliable in these circumstances

1. secondary dentin deposits
2. moisture contamination
3. immature tooth (open apex)
4. pt taking analgesics

21

SLOB rule

lingual CLOSEST to cone
buccal FARTHER from cone

22

if xray taken from MESIAL, the lingual surface (ML canal) will appear more ___ than the buccal surface (MB canal) which appears ___

ML canal more MESIAL
MB canal appears farther DISTALLY

23

if xray taken from DISTAL, the lingual surface (ML canal) will appear more ___ than the buccal surface (MB canal) which appears ___

ML more DISTAL
MB more MESIALLY

24

Dx tests for recently traumatized teeth (4)

1. soft tissue exam
2. hard tissue exam
3. xray
4. observe adj. and opposing teeth for injury

25

Dx tests CONTRAINDICATED for recently traumatized teeth (2)

1. EPT - pulp undergoes temp. paresthesia
2. percussion - painful

26

radiation safety

1. stand 6 ft away, 90-135 deg. to beam
2. FAST E-speed film
3. 70 kVp or higher (higher = lower dose)
4. collimation < 2.5 in.
5. use lead apron and thyroid collar
6. max. dose = 50 mSv/yr

27

PULPOTOMY indicated for (4)

1. cariously exposed primary teeth with healthy pulp
2. trauma or carious exposure of immature permanent teeth
3. instead of EXT when you can't RCT
4. emergency for permanent teeth with acute pulpitis

28

can you do pulpotomy on fully developed permanent teeth?

NO. Not successful - it's only temporary tx

29

if doing pulpotomy on immature permanent tooth and bleeding isnt controlled you:

amputate at more apical level

30

uncontrolled bleeding is a sign of

inflamed pulp tissue

31

for successful pulpotomy radicular pulp must be

uninflamed (can always go more apical)

32

if apical amputation in pulpotomy can't control bleeding then:

use hemostatic agents and monitor

if vitality lost -> APEXIFICATION (pulpectomy)

33

pulpotomy is removal of ___ contents

pulp chamber only

34

APEXIFICATION goal

induce further root development in pulpless (dead) tooth by stimulating formation of hard substance at apex to allow obturation of root canal space

35

apex closes ___ yrs after eruption

2-3

36

apexification procedure

1. isolate, access, remove all pulp
2. calcium hydroxid-methylcellulose paste (ex. pulpdent), double cement seal
3. recall 3 mo. (if no apexification, new paste)
4. RCT

37

CaOH action

promotes formation of hard substance at root apex by creating ALKALINE environment

38

permanent tooth fractures, has fully formed root, LARGE exposure

what tx?

RCT

don't need apexification because root is formed

39

permanent tooth fractures, has fully formed root, SMALL exposure, SHORT TIME (30 min. - 1 hr.)

what tx?

DIRECT PULP CAP with CaOH

40

what is a PULP CAP?

most common dressing for pulp cap is?

sedative and antiseptic dressing on exposed HEALTHY pulp; allows recovery and maintain normal fxn and vitality

Dycal = calcium hydroxide

41

2 situations where pulp cap has better success

1. accidental exposure of pulp (NOT carious)
2. pulp of young child (NOT older ppl)

42

young pulps are more/less vascularized?

MORE, so more amenable to repair

43

pulp cap repair occurs when ____ forms at the exposure site

dentin bridge

44

pulp capping not recommended in primary teeth with CARIOUS exposures because

-high failure rate
-pulpotomy very successful

45

if pulp cap fails and tooth becomes symptomatic, might not be able to RCT because of

___ can also cause pulp space calcification and cause a ___ color

severe calcifications in root canal -> perf

trauma; yellow

46

INDIRECT PULP CAP is

procedure is

calcium hydroxide base on thin layer of questionable dentin remaining over pulp

1. 3-4 mo. wait then reopen tooth
2. remove remaining decay

47

if indirect pulp cap and SYMPTOMATIC (heat, percussion) and exposure

eventually RCT

in meantime, EUGENOL + IRM

48

DIRECT PULP CAP is

calcium hydroxide base directly on SMALL (< 1 mm) exposure

49

favorable factors for direct pulp cap

-uninflamed pink pulp
-no excess bleeding
-no symptoms of pulpitis
-small non-carious exposure (mechanical)
-clean cavity

50

direct pulp capping very successful in __ teeth

immature

51

direct pulp cap goal

stimulate DENTIN BRIDGE; preserve underlying pulp tissue in healthy condition

52

don't do direct pulp cap on teeth with

hx of pain, percussion (+), periapical radiolucency

---> RCT

53

failure of direct pulp cap indicated by

symptoms of pulpitis or no vitality

54

adverse responses after direct pulp cap (3)

1. necrosis
2. calcification
3. internal resorption

55

criteria before canal is obturated (4)

1. good preparation to allow debridement and access to apex
2. asymptomatic tooth; dry
3. negative bacteria culture
4. no nerve (shouldn't respond to thermal test)

56

ACCESS PREP objectives (4)

1. straight line access
2. conserve tooth
3. unroof pulp chamber
4. remove pulp horns

57

what kind of access for maxillary primary incisors?

facial

58

common access istakes

1 Md molars - mesial under marginal ridge, lingual under lingual cusps
2. Md incisors - perf
3 Mx 1st PMs - perf

59

DEBRIDEMENT is

removal of foreign material and contaminated/devitalized tissue

60

most crucial aspect of RCT is

CHEMOMECHANICAL debridement

61

best/most reliable indicator of good debridement is

glassy, smooth walls

62

clean shavings on file or clean irrigant can measure good debridement, T/F?

F

inaccurate! need glassy, smooth walls

63

most common cause of root canal failure is

incomplete/inadequate disinfecting the root canal

64

2nd most common cause of root canal failure is

__%?

leakage from badly filled canal

40%

65

most effective way to reduce canal microorganisms is

complete canal debridement

66

objectives of root canal OBTURATION (3)

1. fluid tight seal at apical foramen
2. filling of root canal space
3. favorable biologic environ. for tissue healing

67

if accessory/lateral canal not filled during obturation, the tx is:

eval every 3 mo.

68

after endo, takes ___ mo. before you see radiolucency get smaller on xray

6-12 mo.

69

after RCT, desirable changes are (3)

1. regeneration of alveolar bone
2. deposition of apical cementum
3. PDL re-establishment

70

indications for solvent-softened custom GP cones (3)

1. no apical stop
2. abnormally big apical portion of canal
3. irregular apical portion of canal

71

solvent softened custom cones not used if __ is achieved

TUGBACK

it doesn't result in a better apical seal; should have a APICAL SEAT

72

master cone should reach how far

to apical position of prep or 1 mm short of foramen

73

why do you recapitulate?

clean apical segment of DENTIN filings not removed by irrigation

use your MAF after each increase in file size

74

regaining canal patency

-crown down (large to small)
-rotary > heated instruments
-light pressure with NiTi rotatry files

75

glass bead sterilizer sterilizeds files in __ sec at __ temp

15 sec
200 C (428 F)

76

techniques to remove GP

-rotary
-ultrasonic
-heat
-heat + instrument
-file
-chemical

77

reagent to dissolve GP

chloroform

others - xylol, halothane, benzene, carbon disulfide, essential oils, methyl chloroform, white rectified turpentine

78

irrigants (3)

1. sodium hypochlorite (NaOCl)
2. hydrogen peroxide (3%)
3. urea peroxide (gly-oxide)

79

irrigant bactericidal action better than ___

intracanal meds

80

NaOCl

-most common
-conc. in 1%, 2.6%, 5.25% (not agreed which is best, all OK)
-good tissue solvent, antimicrobial, lubricant
-toxic to vital tissue

81

can disinfect GP points in __ solution for how long?

5.25% NaOCl, 1 min.

82

2 modes of action of hydrogen peroxide (H2O2)

1. BUBBLING - foams debris from canal, an EFFERVESCENT effect
2. liberation of OXYGEN - kills anaerobic bacteria

83

Urea peroxide (gly-oxide)

-avail. in anhydrous glycerol base (gly-oxide) to prevent decomposition
-better tolerated by tissue than NaOCl
-has BETTER solvent action and MORE germicidal than H2O2

84

good irrigant for canals with normal PA tissue and WIDE apices

urea peroxide (gly-oxide)

85

best use for gly-oxide is ___ canals

narrow, curved

utilize slippery effect

86

chelating agents (3)

1. ethylene diamine tetra-acetic acid (EDTA)
2. EDTAC (EDTA + Cetavlon)
3. RC-Prep

87

chelating agents act on ___ tissues with little effect on ___ tissues

work on CALCIFIED tissues with little effect on PERIAPICAL tissue

88

action of chelating agents

act by substituting Na+ ions that combine with dentin to form soluble salts for Ca+ ions that are bound in a less soluble combination

canal edges become softer

helps prepare sclerotic canals after apex is reached with a fine instrument

89

EDTA

-removes mineralized portion of smear layer
-self-limiting, decalcifies up to 50 mm of root canal wall, stops as soon as chelator is used up
-17% conc.
-active in canal 5 days

90

EDTAC (EDTA + Cetavlon)

-greater antimicrobial action than EDTA
-more inflammatory potential
-inactivated by NaOCl

91

RC Prep

-foamy solution
-combines EDTA and urea peroxide
-provides chelation and irrigation
-natural effervescense increased by irrigation with NaOCl

92

zinc oxide eugenol

-based root canal sealer
-fill discrepancies between core filling material and dentin walls (more important than core filling)

93

ZOE functions (3)

1. lubricant for gutta percha
2. forms bond btw gutta percha and dentin
3. antibacterial

94

ZOE disadvantages

-staining
-slow setting time
-non-adhesion
-solubility

95

radiopacity in sealers are from

metallic salts

96

after filling canal with gutta percha, if there is a horizontal line of material (gp or sealer) extending mesially and distally from canal to PDL space -> indicates ___

root fracture

97

MTA

-best retro filling material
-seals APICAL portion of canal

98

___ must be placed when an apical seal may be faulty

reverse filling (MTA)

ex. calcified root canal

99

advantages of MTA (5)

disadvantages of MTA (2)

pros
1. radiopaque
2. hydrophilic
3. biocompatible
4. non-toxic
5. induces hard tissue formation

cons
1. hard to manipulate
2. long-setting time

100

apicoectomy

oblique resection of most apical portion of root

flap tissue, buccal bone around root apex removed, area curetted

101

indications for apicoectomy

-reverse filling placed, need to gain access to area of pathosis
-poorly filled apical portion removed to level of canal obturated

102

most common reason for apicoectomy and retrograde filling

retreating teeth with posts

103

indications for periradicular surgery

1. non-negotiable canal, blockage, severe root curvature
2. complications from accidents ex. instrument separation, ledge, perf
3. failed tx from irretrievable posts or root fillings
4. horizontal apical fractures where apical end of pulp becomes necrotic
5. biopsy to dx non-odontogenic causes of symptoms

104

periapical curettage

same as apicoectomy but does NOT remove root apex

objective: remove and examin diseased tissue and determining extent of lesion

105

most common bleaching agent for endo tx teeth

superoxol

106

superoxol

30% aqueous solution by weight of H2O2 in distilled water

potent oxidizing agent whose bleaching effect is from direct oxidation of stain-producing substances

107

superoxol technique

apply heat to superoxol-saturated cotton pellets in tooth chamber; repeat until tooth is lighter

heat liberates oxygen in the bleaching agent

108

most probable post-op complication of bleaching is

acute apical periodontitis

109

acute apical periodontitis (AAP)

-pain triggered by chewing or percussion
-alone does not indicate irreversible pulpitis

110

AAP indicates

irritated apical tissues assoc. with a vital pulp with potential reversible pulpitis

111

walking bleach technique

place thick paste of sodium perborate and 203 drops of superoxol in tooth chamber with temporary restoration

112

broken instrument past apex -> what tx?

surgery

easier if wedged coronal or at curvature of canal but difficult if passed canal curvature

113

if instrument breaks in canal and periapical radiolucency present with minimal canal enlargement before the accident -> what tx?

surgery because periapical tissues had little opportunity for healing

obturate to block then apicoectomy sand retrofilling

114

if instrument breaks in canal's APICAL 1/3 and lodged tightly and no radiolucency

remaining space filled with gutta percha, eval. 3-6 mo. recall

115

prognosis of tooth with broken instrument is best if

vital pulp
no periapical lesion

116

nickel titanium methods

1. push and pull stroke
2. reaming motion
3. engine-driven rotary (only reaming)

117

what determines canal preparation's shape

instrument's ACTION
not type of instrument

118

filing

push-pull with emphasis on withdrawal troke

-more efficient than reamers
-greater number of flutes in contact with walls
-produces canal IRREGULAR in shape -> must be filled with gutta percha

119

reaming

clockwise rotation especially in insertion

-canal is ROUND in shape
-most efficient if using a silver cone to fill

120

circumferential filling

push-pull filing that scrapes walls to create smooth, tapered prep

-enhances prep when flaring method used

121

canal's widest diameter should be at ___; narrowest diameter at ___

widest at ORIFICE
narrowest at dentinocemental junction (0.5-1.0 mm from radiographic apex)

122

___ mm from apex is where teeth should be filed to and filled

0.5-1.0 mm

123

barbed broaches are for

removing pulp tissue, cotton, other soft materials

NOT for canal enlargement

barbs represent a weakened point

124

hedstrom files are an effective ___ instrument

H-Type stainless steel

made using a sharp, rotating cutter to gauge triangular segments out of round blank shaft to make a sharp edge

125

hedstrom files should be used only with a ___ action

FILING

-> planes dentin walls faster than K-files or reamers

126

S-file is a modified ___ file

Hedstrom

127

K files are best for removing

hard tissue to ENLARGE canals

made by twisting a blank (SQUARE stainless steel rod)

128

K-file action in canal is in what direction?

directs pressure in what direction?

clockwise-counterclockwise

direct pressure apically (filing or reaming action)

129

what type of file is the strongest and cuts least aggressively?

K-file

K-flex file is a modified K-file

130

2 types of K isntruments

1. K files
2. Reamers

131

reamers have more/less flutes than k-files?

FEWER

132

reamers are used in canals to ___ in only a ___ action to enlarge canals

remove debris using clockwise/counterclockwise reaming action?

place materials in apical portion using clockwise/counterclockwise rotation?

SHAVE DENTIN in reaming action

CLOCKWISE for debris

COUNTERCLOCKWISE for materials

133

5 critical factors to manage traumatic avulsions

1. time
2. storage media
3. tooth socket - don't curette
4. root surface - don't scrape, dry
5 splint stabilization - up to 2 wks to allow reattachment of PDL

134

teeth replanted by __ min show little resorption

teeth replanted after ___ hrs have extensive root resorption

30

2 hrs

135

best storage media

MILK

because of neutral pH 6.5-6.8 and osmolality (for cell survival)

136

mgmt of avulsed permanent tooth replanted within 2 hrs of trauma

10-14 days after replant - clean and shape + CaOH

replace every 3 months for 1 yr

if resorption stopped, fill with gp

137

mgmt of avulsed permanent tooth > 2 hrs of trauma

ankylosis and ext root resorption probably after 2 yrs

RCT BEFORE replantation
soak tooth in 2.4% fluoride solution at 5.5pH for 20 min.
curette blood clot, irrigate with saline
rinse tooth with saline, replant

splint 4-6 wks

138

in re: avulsed tooth out > 2hrs

ankylosis gives better/worse prognosis than ext root resorption

BETTER

ext root resorption leads to failure

139

PDL cells die after __ min

60 min. of dry storage

tap water is just as bad!

140

saliva has storage up to __ hrs
milk has storage up to __ hrs

saliva = 2
milk = 6

141

when do you RCT teeth with complete roots after avulsion?

asap!

142

teeth with incomplete roots might not need RCT if replanted within ___ min

30

143

what is the most frequent sequela to avulsed tooth replantation?

root resorption

144

external root resorption is caused by

-periradicular inflammation
-dental trauma
-ortho
-impacted teeth
-bleaching of non-vital teeth

145

external root resorption is always accompanied by __ and is the chief cause of failure of replantation of permanent teeth

bone resorption

146

3 types of external root resorption

1. surface
2. external inflammatory resorption
3. replacement resorption

147

surface resorption (1)

-caused by ACUTE INJURY to PDL and root surface
-healing forms new cementum and PDL
-root resorption limited to cementum, can heal, can't see on xray

148

external inflammatory resorption (2)

infected pulp complicates resorptive process; BOWL-SHAPED resorption areas
-involves cementum and dentin
-need necrotic pulp and bacteria
-immediate RCT stops it

149

replacement (ankylotic) resorption (3)

substituted by bone

150

causes of internal (inflammatory) root resorption

dental trauma, partial removal of pulp (pulpotomy), caries, pulp capping with calcium hydroxide, cracked tooth

151

INTERNAL (inflammatory) ROOT RESORPTION

-causes loss of vitality
-inflammation from infected CORONAL PULP is usually the cause

152

teeth with internal resorption have hx of

trauma, crown prep, pulpotomy

153

undifferentiated reserve C.T. pulp cells are activated to form ___ that resorb tooth structure in contact with pulp

dentinoclasts

154

in internal resorption, what does the root canal look like

anatomy is altered and increases in size, appears as irregular radiolucency, the canal "disappears" into the lesion

155

tx of choice when internal resorption is detected

PULPECTOMY so resorption stops

156

internal resorption can only occur when

some pulp tissue is VITAL

note: negative does not rule out this etiology

157

pink tooth is a sign of ____

pink cause of ___

pathognomonic sign of internal resorption;
sometimes a sign of cervical root resorption

pink cause of granulation growth undermining coronal dentin

158

INTENTIONAL REPLANTATION (replant sx) and its indications (4)

-tooth that needs endo is removed, prepped, and returned

Indications
1. routine endo is impossible
2. canal blocked and periapical sx impractical
3. perf
4. previous tx failed, but non-sx tx or sx impractical

*only consider when no other alternative tx to maintain

159

how should the socket wall be treated during replantation?

don't touch!

160

why don't you replant primary teeth?

potential danger to permanent successor
-infxn, ankylosis

161

functions of PULP (3)

1. dentin formation
2. induction - forms dentin -> enamel formation
3. nutrition - tubules (hydration, form peritubular dentin)

162

first formed dentin laid before odontoblast layer is organized is ____

mantle dentin

163

most dentin is ___ dentin

circumpulpal

164

___ dentin forms after eruption and through life; results in gradual asymmetric rdxn in pulp size

secondary

165

irregular and disorganized dentin layer in response to injury or irritants

tertiary dentin (reparative)

166

as dental pulp ages, # of reticulin fibers increases/decreases

DECREASES
pulp is LESS CELLULAR and MORE FIBROUS

size of pulp decreases

167

as pulp ages, collagen fibers and calcifications within pulp increase/decrease?

INCREASE

168

pulp stones

calcifications assoc. with chronic pulpal disease

169

nerves in pulp

-myelinated (sensory)
-unmyelinated (motor) = regulate lumen size of blood vessels
-afferent sympathetic

170

are proprioceptors present in pulp?

NO
(they respond to stimuli regarding movement)

171

what is the only nerve ending found in pulp?

free nerve endings
-it's a SPECIFIC pain receptor
-regardless of source of stimulation, the only response is PAIN

172

cells in pulp;

cells in DISEASED pulp

pulp
1. fibroblasts (mainly)
2. odontoblasts
3. histiocytes (macros and lymphocytes)

diseased pulp
1. PMNs
2. plasma cells
3. basophils
4. eosinophils
5. lymphocytes
6. mast

173

during pulpal inflammation these cells are involved in response, NOT __

involved = plasma cells, macros, lymphocytes

NOT PMNs

because there's no direct pulp exposure, it's not an ACUTE response. after exp then PMNs are chemotactically attracted

174

vital pulp response to microbial invasion is very resistant because after 2 wks exposure, only ___ mm of coronal pulp has given in

2 mm

175

apical or coronal portion of pulp has more collagen?

apical

Type 1:3 = 55:45
Type 5, small amts

176

what type of collagen predominates in dentin

Type 1

177

fibroblasts in pulp make what types of collagen? (2)

Type 1 and 2

178

central zone (pulp proper) contains ____

list 3 layers

nerves, blood vessels

1. cell-rich zone (innermost) - fibroblasts
2. cell-free zone (zone of Weil) - capillaries, nerves, nerve plexus of Rashkow
3. odontoblastic layer (outermost) - odontoblasts, next to predentin & mature dentin

179

absence of what layer predisposes dentin to internal resorption?

predentin

10-47mm of dentin matrix is unmineralized next to the odontoblastic layer

180

__ wall of md teeth is most easy to perf

lingual wall
cause of lingual inclination

181

__% of md 1st PM has 2 canals with 2 apical foramina

25%

23% can have 2 or 3 canals

182

radiographic indication that 2 canals present

pulp canal disappears midroot

183

referred pain to mental region of mandible might be from these teeth (3)

md 1st PM
md 2nd PM
md canine
md central

184

__% md 2nd PM has 1 canal at apex

97%

-oval access
-close to mental foramen

185

pulpitis in this tooth can refer pain to the EAR

md 1st molar

186

md 1st molar has a ___ shape outline

__% cases, distal root has 2nd canal

trapezoid

40%

-pulp chamber located in mesial 2/3 of crown

187

md canine, root canal wall is thin M-D/B-L? and wide M-D/B-L?

thin mesiodistally
wide labiolingually

188

in the md central, if there are 2 canals, which one is straighter?

labial

access is long oval

189

mx incisors, canines have __ axial inclination

DISTAL - angle bur to distal to avoid perf of mesial root

190

referred pain to FOREHEAD can be from these teeth

mx central, mx lateral

191

mx central/lateral is most likely to have a curved root

lateral

192

mx central root anatomy

access is OVAL-TRIANGULAR (more tri)

193

mx lateral root anatomy

access is OVAL

more slender than central, often has distal and/or lingual curvature or dilacerations

194

pulpitis in mx canine can refer to what area?

NASOLABIAL

195

how many canals for mx 1st PM?

2 canals

60% have 2 roots (B, palatal), usually equal in length

196

which tooth has a canal cross section shaped like a figure 8 ellipse?

mx 1st PM
-> access is THIN OVAL

careful don't perf on mesial (mesial concavity)

197

mx 2nd PM refers pain where?

usually has how many roots?

temporal (more)
nasolabial

85% 1 root, 15% have 2 roots

access is THIN OVAL

198

mx 1st or 2nd PM has higher incidence of accessory canals?

mx 2nd PM

199

mx molars pulp chamber outline is

TRIANGLE

-line connecting mesial and palatal is longest
-59% 4th canal usually lingual to MB

200

most missed canal in mx 1st molar

palatal canal curves to ___

MB cause it's under MB cusp; access from DL position, often splits into 2 canals

curves to FACIAL

201

u-shaped radiopacity overlying palatal root apex is most likely?

zygomatic process

202

which nerves are distributed in the subnucleus caudalis of trigeminal nerve (CN V)?

CN VII, IX, X

creates potential of referred pain to many sites

203

transplantation is

transfer of tooth from one socket to another in same person or another person

when root isn't fully developed - better prognosis

204

force controlled vertical tooth movement occlusally in a socket is called

orthodontic extrusion

INDICATIONS
-prior to implant
-untx subgingival pathoses

205

to stablize intentionally replanted tooth

ask pt to close in CO for rest of the day

206

disadvantage of endodontic implants is

lack of apical seal

207

procedure to apically position gingival margin and/or reduce cervical bone is called

crown lengthening

-to tx subg caries, perfs, resorptions

208

root submersion

resection of tooth roots 3 mm below alveolar crest then cover with mucoperiosteal flap

-will prevent alveolar resorption and maintain better proprioception

INDICATIONS
-rampant caries, adverse periodontal conditions, repeated failure of prosthetic cases, med complex, avoid esthetic defect

209

the earliest and most common symptom of pulpal edema/inflamed pulp (acute pulpitis)

thermal sensitivity

usually involves increased and persistent pain to cold

210

best way to test thermal response

rubber dam; bathe each tooth in hot/cold water

211

thermal test false (-) in teeth that are

immature

recently traumatized

or premedicated with analgesic

212

__ is the only reliable clinical evidence that 2' dentin has formed

decr. tooth sensitivity (cause tubules calcified)

213

conditions that DON'T require endo (3)

1. cementoma (periapical cemental dysplasia) - usually anterior md, wont' affect pulp vitality

2. traumatic bone cyst - not true cyst cause no epithelial lining, teeth usually vital

3. globulomaxillary cyst - jxn of globules and mx processes, btw lateral and canine, tooth vital

214

conditions that DO require endo (4)

all NONVITAL

1. apical scar - periapical granuloma, cyst, abscess

2. radicular cyst

3. chronic dental abscess

4. chronic periapical granuloma - asymptomatic, most COMMON sequelae of pulpitis

215

___ is a condition that results from a pulpal infxn that extends through the apical foramen into periapical tissues

periapical abscess

MOST COMMON of all abscesses
-pus in alveolar bone at root apex after pulp dies
-first symptom is tenderness -> throbbing with swelling
-won't respond to EPT or cold but maybe heat
-ER: drain and rx abx -> RCT

216

acute osteomyelitis is most commonly caused by

dental infection
-occurs in jaw
-serious sequelae of periapical infxn
-often spreads into MEDULLARY SPACES
-severe pain, temp/fever, lymphadenopathy
-teeth are loose and sore

217

radiographic features of acute osteomyelitis

-takes 1-2 wks to see it
-diffuse lytic changes -> MOTH EATEN radiolucency

218

__ is an acute abscess that develops through the periodontal pocket; involves alveolar bone loss, pocket formation, periodontal pathologic conditions

periodontal abscess

palpation (+)
percussion (+)
EPT responsive (UNLIKE periapical abscess)

BACTERIA = gram (-) rods ex. capnocytophaga, vibrio, fusobacterium

219

__ is a rare abscess that occurs when bacteria invade thru a break in the gingival surface

GINGIVAL

-caused by mastication, oral hygiene procedures, dental tx

220

__ is a long-standing low-grade infxn of periapical bone with the root canal being the source of infxn

chronic apical abscess (suppurative apical periodontitis)

-asymptomatic
-tx by RCT

-differential: NOT a cyst or granuloma because those are well-defined radiolucencies

221

__ is an apical lesion that develops as an acute exacerbation of a chronic apical abscess

PHOENIX abscess (suppurative apical periodontitis - recrudescent abscess)

-granulomatous zone gets infected
-dx on acute symptoms and xray

percussion (+)
x-ray: big PA radiolucency

222

massive invasion of pulpal contaminants will result in a __

acute abscess (Phoenix)

223

__ to __ % of bone must be altered before you see it on an xray

30-50%

occurs at the jxn between the cortical and cancellous bone

224

__ is a localized collection of pus inside alveolar bone at the apex after pulpal death, with infxn extending into periapical tissue

acute apical/alveolar abscess (AA)

-1st symptom is tenderness -> throbbing, swelling
-tooth might get loose, pt gets fever

EPT (-)
Cold (-)
Heat (+) maybe

Tx: drain, later RCT

225

__ is a growth of granulomatous tissue continuous with the PDL due to pulpal death with diffusion of toxic products into the periapical area

granuloma

-usually asymptomatic
-xray: well defined radiolucency with some irregularity

226

__ is an inflammatory response of the periapex that develops from pre-existing granulomatous tissue

central, fluid-filled, epithelium-lined cavity, surrounded by granulomatous tissue and peripheral fibrous encapsulation

CYST

-asymptomatic
-xray: well defined radiolucency

227

granuloma and cyst are only differentiated by

HISTOLOGY

228

in endo-perio lesions, what tx is first?

endo

perio first only if it's primary periodontal lesion

229

common clinical finding of perio prob is

pain to lateral percussion on a tooth with wide sulcular pocket

230

probing lesions (3)

1. conical-shaped
2. blow-out (acute)
3. narrow sinus tract

231

conical shaped probing lesion

can't be managed by endo alone, typical of perio problem, bone loss at crestal bone and progresses apically

232

blow-out (acute) probing lesion

non-vital (necrotic) pulp that can completely heal after RCT, normal sulcus depth until area of swelling (drops near apex)

233

narrow sinus tract lesion

normal probing depth, except narrow area, probe can pass down root to some distance

tooth is non-vital

234

reversible pulpitis (pulpal hyperemia = pulpal inflammation)

-most commonly caused by bacteria
-pain requires external irritant to evoke painful response
-sharp and brief pain, stops when irritant is removed
-percussion (-)
-pulp responds more to cold than hot

235

__ is an excess accumulation of blood in the pulp due to vascular congestion

pulpal hyperemia
-engorgement of pulpal vessels with blood
-when you remove the cause -> pulp normal

236

how do hyperemic teeth respond to EPT

lower current than normal

237

best way to reduce pulp injury during tooth prep is to

minimize dehydration of dentin

238

irreversible pulpitis (acute pulpitis) is

a condition characterized by SPONTANEOUS PAIN with periods of cessation, intermittent

-LINGERS after irritant is removed
-usually not readily localized
-incr. by heat and relieved by cold
-lying down or bending over intensifies the pain (incr. pressure)
-percussion (+)

239

necrotic pulp (pulp death)

-may have no painful symptoms, no EPT response
-sometimes response to heat but not cold

240

bacteroides involved in pulpal-periradicular infxn (2)

porphyromonas
prevotella

241

bacteria species in infected root canals (5)

1. eubacterium
2. peptostreptococcus
3. fusobacterium
4. porphyromonas
5. prevotella

242

what species isnt as important in the progression of caries as it is the initiation?

streptococcus

243

virulence factors in periradicular pathosis (4)

1. LPS (gram - bacteria)
2. enzymes - neutralize abs and complement components
3. extracellular vesicles - bacterial adhesion, proteolytic activities, hemagglutination, hemolysis
4. fatty acids - affect chemotaxis, phagocytosis

244

if vital pulp is exposed for 2 weeks, bacteria won't penetrate more than __ mm

2 mm

245

endo contraindications

1. non-restorable/non-strategic tooth
2. bad peiro support
3. vertical root fracture
4. internal/external resorption
5. can't instrument canal/surgery

246

is hemophilia a contraindication to endo?

no but check with physician

247

post guidelines

-leave 4 mm gutta percha
-threaded screw posts incr. fracture -> PARALLEL and TAPERED are preferred
-cusps adj. to lost marginal ridges should have ONLAY

248

why are endo posterior teeth more prone to fracture?

destruction of coronal structure

249

min. restoration for endo tx teeth is

onlay -> cuspal coverage

250

pulp chamber retained amalgam, __ mm into each canal

3 mm

251

Anterior tooth fractures are usually do to

Accidental trauma

252

RCT for horizontal root fracture is not indicated if

Fracture site remains in close proximity and pulp is vital

253

Symptoms of cracked tooth syndrome

Sharp, brief pain occurring unexpectedly when pt chews

254

3 types of surgical flaps

1. Submarginal curved (semilunar)
2. Submarginal triangular and rectangular (Ochsenbein-Leubke)
3. Full mucoperiosteal