Endo Flashcards
1
Q
What is the aetiology of pulpal and periapical disease
A
- Microorganisms entry towards pulp/ root canal via:
- Dental caries
- Cracks
- Trauma
- Resorption
- Perio related
- Micro leakage
2
Q
When distance should bacteria be to exhibit pulp change
A
- No significant damage occur when bacteria have penetrated within 1.1mm
- Irreversible damage if they penetrate to within 0.5mm of pulp
3
Q
How does a periapical lesion form
A
- Bacteria present in the root canals
- Non-specific response
- Specific host response
4
Q
what is acute periodontitis
A
- Acute inflammation at the apex
- Infection may develop into primary abscess
- Maybe from an acute exacerbation of a chronic apical periodontitis
5
Q
What is chronic apical periodontitis
A
- Inflammation at the tooth of a long standing nature
- Presence of:
- Granulomatous tissue
- Predominantly lymphocytes, plasma cells and macrophages
- Either epithelised or non epithelised
6
Q
What is a periapical true cyst
A
- It is a distinct pathological cavity completely enclosed in an epithelial lining so that no communication to the root canal
7
Q
What is a periapical pocket cyst
A
- A periapical pocket cyst, also known as a periapical abscess with sinus is a type of dental cyst that forms at the root apex of a non-vital tooth. It results from chronic periapical inflammation.
- the cyst wall is not completely enclosed, and the lesion communicates with the root canal system
- (responds to root canal treatment)
8
Q
What bacteria found in necrotic pulp
A
- Anaerobes mainly
- Streptococcus
- Fusobacterium
- Lactobacillus
9
Q
What are extra radicular infections
A
- Minority of infections
- E.g acute apical abscess
10
Q
What are the contraindications for root canal treatment
A
- Teeth cannot be made functional or restored
- Insufficient periodontal support
- Poor prognosis: extensive external/internal resorption, extensive vertical fracture
- Patient unable to tolerate rubber dam
- Complex anatomy
- Uncooperative: limited mouth opening, unable to attend appointments
11
Q
What are some limitations of radiographs
A
- Degree of magnification
- Superimposition
- Geometric distortion
- Lack of standardisation or reproducibility
- Not all periapical lesions can be detected
12
Q
What is the clinical classification of pulpal disease
A
- Reversible pulpitis
- Irreversible pulpitis
- Hyperplastic pulp
- Pulp necrosis
13
Q
Tell me about reversible pulpitis
A
- Transient
- Pain doesn’t linger
- Difficult to localise
- Not TTP
- Dentinal sensitivity mimic symptoms of reversible pulpitis
- Treatment: remove cause, cover exposed dentine
14
Q
Tell me about irreversible pulpitis and treated how
A
- Results from more severe insult on the pulp
- Pain spontaneous
- Severe pain
- Pain lingers
- Pain to hot liquids relieved by cold
- Later stages widened PDL
- Treatment: RCT or extraction
15
Q
What is a hyperplastic pulp and treatment
A
- Form of irreversible pulpitis
- Known pulp polyp
- Due to proliferation of chronically inflamed young pulp tissue.
- Treatment: RCT or XLA
16
Q
What is pulp necrosis and treatment
A
- Occurs at the end of irreversible pulpitis
- Pulp is non-responsive to pulp testing and is asymptmatic
- Reasons: calcification, history of trauma, simply tooth not responding
- Treatment: RCT or XLA
17
Q
What is internal resorption
A
- Occasionally pulp inflammation may result in resorption of the dentine by dentinoclast cells
- Clinically a pink spot can be seen
- Special investigation: CBCT (perforation), PA
- RCT or if too advanced XLA
18
Q
What is pulp calcification
A
- Secondary dentine: after eruption, laid of floor and ceiling of pulp
- Tertiary dentine laid in response to environmental stimuli
- Reactionary dentine response to mild stimuli
- And reparative dentine in response to strong noxious stimuli
19
Q
What are the 4 clinical classifications of periapical disease
A
- Acute apical periodontitis
- Chronic apical periodontitis +/-(Acute Excerbation)
- Apical periodontitis with an abscess (Acute or Chronic)
- Apical periodontitis with a sinus tract (Acute or Chronic)
20
Q
How to distinguish between sinus tract and periodontal disease
A
- Sensibility testing: normal if periodontal pocket, no response for sinus tract
- Periodontal probing: wide pockets is perio and narrow tract is sinus
- Clinical tooth status: minimal caries in perio and evidence of caries. Resto in sinus
- General periodontal condition: poor is perio and normal if sinus
21
Q
What are sources of communication into the pulp/canal
A
- Apical foramen
- Lateral canals : any part of root including furcation
- Dentinal tubules: once root cementum is lost
- Perforations
- Fractures: horizontal and vertical
- Developmental anomalies: root grooves allow bacterial colonisation
22
Q
What is the classification of endo-periodontal lesions
A
- With root damage: fracture, perforation, external root resorption
- Without root damage: perio patients (3 grades) and non perio patients (3 grades)
23
Q
What is cracked tooth syndrome
A
- Vital teeth:
- Sharp pain on biting on release
- Occasional pain from cold
- Difficult to localise
- Tooth slooth, staining, transillumination
- More common in mandibular molars
- Treatment: ortho band, cuspal coverage
- Non vital:
- Dull ache on biting
- TTP, narrow perio pocket adjacent to fracture
- Radiographically halo or J shaped diffuse lesion around root
- Treatment: RCT or hemisection
24
Q
Non odontogenic pain-Neuropathetic that can mimic odontogenic pain
A
- Trigeminal neuralgia
- Atypical odontalgia
- Glossopharyngeal neuralgia
25
What are some discussion with patient about RCT (3)
- RCT not 100% success rate (85%-95%)
- Re-RCT 77-80% success rate
- Flare ups can happen after treatment
26
Why use a rubber dam in RCT
- Prevents inhalation or ingestion
- Prevents infection via saliva
- Enhances access and retracts soft tissues
- Better comfort for patient
- Medico legal requirement
27
Name some irrigants
- Sodium hypochlorite: antibacterial, dissolves organic tissue remnants
- Chlorhexidine
- EDTA
28
Why use calcium hydroxide intra canal
- Antibacterial
- High pH
- Biocompatible
- Non irritant
- Degrades residual organic tissue
29
What is anatomy of maxillary incisors
- 1 canal
- 22mm
- Triangle shape access cavity
30
What is anatomy of mandibular incisors
- 40% have 2 canals that join
- 20mm
- Triangular access cavity
31
What is anatomy of maxillary canine
- 1 root canal
- 26mm
- Triangular/ ovoid access
32
What is anatomy of mandibular canine
- 22.5mm
- Mainly 1 canal (14% 2 that join)
- Triangular/ ovoid access
33
What is anatomy of maxillary 1st premolars
- 20.6mm
- 2 roots and 2 canals
- Ovoid bucco-palatal
34
What is anatomy of maxillary 2nd premolar
- 21.5mm
- Usually single rooted
- Ovoid bucco-palatal
35
What is the anatomy of mandibular premolars
- 21.6mm
- Single root
- Ovoid bucco-palatal
36
What is anatomy of maxillary 1st molar
- 20.8mm
- 4 pulp horns
- 3 roots 4 canals usually (90%)
- MB2 is the extra (usually type 2 that joins)
- Mesial 2/3 of occlusal, oblique ridge intact
- Triangular
37
What is anatomy of maxillary second molar
- 20mm
- 3 roots 3 canals
- 60% have 4 canals
- Mesial leave oblique ridge intact
- Triangular
38
What is anatomy of mandibular 1st molar
- 21mm
- 2 roots 3 canals
- 2 mesial 1 distal
- Trapezoid outline
39
What is anatomy of mandibular 2nd molar
- 19.8mm
- 2 mesial 1 distal
- Trapezoid outline
40
What are objectives of cutting a coronal access cavity
- Remove entire rood of pulp chamber
- Allow visualisation of all root canal orifices
- Straight line access
- Have convergent walls in apical direction
- Conserve as much tooth tissue as possible
41
What are the aims of mechanical root canal preparation
- Continuously tapered preparation is produced
- Original anatomy is maintained
- Foramen position is maintained
- Apical foramen is kept as small as possible
42
What are two basic motions of hand files
- Rotational motion
- Push pull filing
43
Tell me about sodium hypochlorite
- Anti-microbial
- Dissolves organic tissue remnants
- Usually 2.5%
- Na(OH)2 accident: irrigate with saline, cause severe pain, blanching
44
What is EDTA
- Remove smear layer-inorganic tissue remnants (17% EDTA)
- Helps in sclerosed canals, ledges
45
What is chlorhexidine in terms of irrigation
- Antibacterial, does not dissolve organic tissue
- Used in concentration 2%
- Do not use with sodium hypochlorite
46
What are the basics of canal preparation sequence
- Explore coronal 1/3-2/3’s with size 10 file
- Prepare coronal 1-3- 2/3’s with GG’s
- Explore apical 1/3 with size 10 file
- Establish patency
- Definitive Working length radiograph
- Prepare apical 1/3 and apical gauge
- Step back (shapes canal and cleans and provides resistance form which to obturate against)
- Smooth canal circumferentially
- Irrigation and patency in between each instrument
47
Coronal preparation crown down approach
- Necrotic case bacterial more coronal (removes bacteria and stops introduction apically)
- Achieve straight line access: reduce curvature, **improve tactile strength**, greater volume of irrigate
48
What is the endpoint of apical preparation
- Apical constriction
- 1mm for Radiographic apex
- Apical foramen is larger as well
49
What is apex locators
- Only use **zero reading**
- Generally work back 0.5mm to **1mm** from the zero reading for WL
- Do not use on patient with **cardiac pacemakers**
- What is **short circuit**: canal too moist, touching metal resto, perforation
50
How can you determine root length
- Electronic apex locator
- Working length radiograph
- Tactile sensation
51
What is patency filling and what are the advantages
- Prevents blockage
- Check whether exude present
- Helps maintain and follow anatomy
- Help deliver irrigant to apex
52
What are the aims intracanal medication and name some
- To **eliminate any remaining bacteria** after canal instrumentation and irrigation
- Calcium hydroxide non setting
- Cortico- Steroids – ledermix (good for inflammation)
53
What are the problems of incorrect instrumentation
- Ledges (file away with EDTA)
- Packed dentine debris/blockages (copious irrigation)
- Perforations (repair glass ionomer, MTA)
- Separated instrument
54
What is obturation
- Sealing the root canal
- Gutta percha (biocomp, insoluble)
- Is a trans-polyisoprene
55
What are the properties of ideal root canal sealer
- Satisfy the requirement of a root filling material as well
- Provide good adhesion to the canal wall
- Expand whilst setting
- Adequate working time and easy mix
- Biocompatible, good flow
56
What are the 4 aims of obturation
- Prevent micro-organisms and their toxins percolating into the peri-radicular tissue
- Seal the remaining bacteria in the root canal system in an environment that they cannot thrive
- Prevent percolation of peri-radicular exudate (nutrient supply for the bacteria) into the root canal space
- Prevent reinfection of the root canal system from the coronal aspect
- Failure of this can be associated with non-healing
57
When to obturate
- Tooth must be asymptomatic
- Temporary dressing must be intact
- No sinus present
- Root canal must be dry
58
Examples of root canal sealers
- Calcium hydroxide: antibacterial, high pH ( encourages repair, active calcification, neutralises lactic acid made by osteoclasts)
- Resin based sealers
- Bio ceramic sealers
- Zinc oxide eugenol sealers (common)
59
What are the basic steps in cold lateral
- Rubber dam
- Master GP with tug back in wet canal
- Dry canal
- Coat GP with sealer and place to WL
- Finger spreader 1mm from WL
- Add accessory points till canal is filled
- Sear of GP at CEJ using Machtou plugger
60
What are you looking at on **post op** rad
- Length
- Quality of condensation (voids)
- Taper
61
How to assess outcome of RCT
- Tooth functional with no swelling or sinus tract
- Patient free from symptoms
- Radiographic evidence of normal peri-radicular tissue
- Radiographic evidence of healing if there has been a periapical lesion at the start
62
What are the obturation techniques
- Cold lateral
- Warm vertical compaction (cut off apex GP and backfill)
- Single cone
- Warm lateral ?
63
What are the clinical applications of MTA
- Pulp cap
- Perforation repair
- Root end filling
- Apexification
- Root resorption
64
What are the clinical applications of biodentine
- Pulp exposure
- Dentine caries
- Pulpotomy
- Apexification
dentine substitute, biocomp, strong, and stimulates dentine formation
65
What is pulp obliteration
- Pulp canal obliteration occurs more frequently with open apices
- Dental pulp undergoes calcification
- Narrowing or obliteration of pulp chamber
- Due to reparative process and placing dentine
- Clinical signs and symptoms are minimal
66
How to do safe irrigation
- Use side venting needle in canal
- Never use excessive force to inject
- Irrigate slowly
- Never bind irrigation needle in canal
- Use high volume suction near cavity
67
Whats the difference between odontopaste and ledermix
- The main difference between Odontopaste and Ledermix paste is that **clindamycin hydrochloride** in Odontopaste replaces **demeclocycline hydrochloride** in Ledermix paste. Clindamycin hydrochloride has an equivalent spectrum of antibacterial activity and exhibits minimal staining of teeth.
- Not routine
68
When to send patient to A&E
- Pyrexic
- Limited opening
- Difficulty swallowing
- Large swelling near the eye
- Crossing the midline under the chin ( bilateral)
69
Perio endo lesion classification (5)
- **Primary endodontic lesion (RCT, good prognosis)**
- Primary endodontic lesion with secondary periodontal involvement (RCT, assess need for perio treatment)
- **Primary periodontal lesion extending to the apex (perio treatment)**
- Primary periodontal treatment with secondary endodontic involvement ( RCT and perio treatment)
- Combined Lesion (RCT and perio treatment)
70
What are the ideal properties of root canal filling materials (4)
- Be radiopaque
- Not stain the tooth
- Removable
- Allow good length control
71
Tell me about rotary files
- **Non cutting tips** for pro taper
- Glide path be created with Stainless steel K files to the depth
72
What does coronal flare do
- Facilitates direct access into middle third of root canal and promotes access of irritants
73
What is the ESE guideline for success of rct (4)
- Absence of pain, swelling and other symptoms
- No sinus tract
- No loss of function
- Radiological evidence of a normal periodontal ligament space around the root
74
How to diagnose perforation (4)
- Bleeding
- Pain
- Instrument angle outside cavity
- Radiographic
75
How to remove broken file
- Magnification and light
- Tweezers
- Stieglitz forceps
- Braiding of h files
- Ultrasonic
- Accept
76
How to remove GP
- Files H files
- Solvents as adjunct – eucalyptus oil
