Endo + Flashcards
(224 cards)
1
Q
Explain the 5 stage process of endodontic diagnosis?
A
- The patient tells the clinician the reasons for seeking advice.2. The clinician questions the patient about the symptoms and historythat led to the visit.3. The clinician performs objective clinical tests.4. The clinician correlates the objective findings with the subjectivedetails and creates a tentative list of differential diagnoses.5. The clinician formulates a definitive diagnosis.
2
Q
What key symptoms will the patient complain of that may suggest pulp involvement?
A
PainSwellingNo sleepBroken toothDiscomfort from hot or coldTooth colour change
3
Q
What questions should the clinician ask the patient about symptoms and history?
A
SOCRATESSite: quadrantOnset: when it started and does it get better/worseCharacter: describe the pain?Radiation:pain to other parts of body?Association:other signs and symptomsTiming: when pain worst?Exacerbate:what sets of the pain? does anything help reduce the pain?Severity:0-10 scale
4
Q
Differential diagnosis for pulpal pain - referred pain?
A
Referred pain:muscle trigger point referred to tooth and mimicked endo involvementSinusitisAcute dental pain can be referred to opposite arc in same side
5
Q
Name the 4 differential diagnoses for pulpal pain?
A
Referred painNeuropathic painCancer Other
6
Q
Name the 3 causes for pulpitis?
A
Physical irritations from extensive decayTraumaAnachoresis (retrograde infections)
7
Q
Name 5 key symptoms for pulpitis?
A
Pain on bitingPain when chewingSensitivity with hot or coldFacial swellingDiscolored tooth
8
Q
What difficulties arise for pulpitis localisation?
A
Referred pain & the lack of proprioceptors in the pulplocalising the problem to the correct tooth can often be aconsiderable diagnostic challenge• Also of significance is the difficulty in relating the clinical status of atooth to histopathology of the pulp in concern• Unfortunately, no reliable symptoms or tests consistently correlatethe two.
9
Q
Name the 7 classifications for pulpal disease?
A
1) Healthy pulp.2) Reversible Pulpitis.3) Symptomatic Irreversible4) Asymptomatic Irreversible5) Pulp Necrosis6) Previously Treated7) Previously Initiated Therapy
10
Q
Name the 6 classifications for periapical disease?
A
1) Normal Apical Tissues2) Symptomatic Apical Periodontitis3) Asymptomatic Apical Periodontitis4) Chronic Apical Abscess5) Acute Apical Abscess6) Condensing Osteitis
11
Q
What to do if the tooth is not restorable or periodontally unsavable?
A
EXTRACTION
12
Q
Name 4 types of special investigations for pulpitis?
A
Tap the tooth – percussion test• Feel the surrounding hard tissue – palpation test• Testing movement of the tooth – mobility test• Shine a light through the tooth ‐ transillumination
13
Q
Name and describe the categories for percussion?
A
None (-): tap on incisal edge of tooth with end of mirror causes no discomfortMild (+): tap on incisal edge of tooth with end of mirror causes little discomfortModerate (++): tap on incisal edge of tooth with end of mirror causes noticeable discomfort(painful)Severe (+++): tap on incisal edge of tooth with end of mirror causes definitive discomfort(very painful)
14
Q
Name and describe the categories for palpation?
A
None (-): feeling buccal and lingual gingiva apical to a tooth with the oad of the finger causes no discomfort at allMild (+): feeling buccal and lingual gingiva apical to a tooth with the oad of the finger causes little discomfortModerate (++): feeling buccal and lingual gingiva apical to a tooth with the oad of the finger causes noticeable discomfort (painful)Severe (+++): feeling buccal and lingual gingiva apical to a tooth with the oad of the finger causes definitive discomfort (very painful)
15
Q
Name and describe the categories for mobility?
A
Grade 0 – no apparent mobility• Grade 1 ‐ mobility less than 1mm buccolingually• Grade 2 ‐ mobility between 1 – 2 mm buccolingually• Grade 3 ‐ mobility greater than 2 mm buccolingually AND apicalmovement greater than 1 mm
16
Q
What is the definition of sensibility testing?
A
e help to determine the pulpal status…alive or dead
17
Q
What are the limitations for a sensibility test?
A
Can't differentiate between:“alive & healthy”“alive and diseased”“alive but just about to snuff it” or“in the process of dying
18
Q
What is the definition of vitality, sensibility and sensitivity testing?
A
Vitality: blood supply present in tissueSensibility: ability to respond to a stimuliSensitivity: responsiveness to a stimuli
19
Q
What is the true determinant for pulp vitality?
A
Vitality
20
Q
Explain how the vitality test works?
A
The pulse oximeter sensor consists of two light‐emitting diodes,one to transmit red light (640 nm) and the otherto transmit infrared light (940 nm) anda photodetector on the opposite side of the vascular bed.The light‐emitting diode transmits red infrared lightthrough a vascular bed such as the finger or ear.Oxygenated hemoglobin and deoxygenated hemoglobinabsorb different amounts of red infrared light. Thepulsatile change in the blood volume causes periodicchanges in the amount of red infrared light absorbed bythe vascular bed before reaching the photodetector.The relationship between the pulsatile change in theabsorption of red light and the pulsatile change in theabsorption of infrared light is analyzed by the pulse oximeter to determine the saturation ofarterial blood.
21
Q
Explain how the sensibility test works?
A
Thermal and electrical tests assess whether the pulp nerve fibres canrespond to a stimulus when applied to the tooth, hence they aresensibility tests
22
Q
Explain how the sensitivity test works?
A
Thermal and electric pulp tests are NOT sensitivity tests, althoughthey can be used to test the sensitivity of a tooth
23
Q
Name the 8 ideal characteristics for an ideal sensitivity pulp test?
A
SimpleObjectiveStandardisedReproducibleInexpensiveNon‐painfulNon‐injuriousAccurate
24
Q
Why can pulpitis diagnosis be wrong sometimes?
A
Diagnosing pulpal and periradicular symptoms is extremely difficultbecause the histopathological condition of the pulp cannot bedetermined by clinical means
25
How can special investigations help with diagnosis?
Sensibility tests are used to try and reproduce the pain thepatient is having & so confirm the source and reason for thepainTooth localisation
26
What should be included during a sensibility test to look out for?
Use control teethUse the information from the history, clinical examinationand findings, other special tests/investigations
27
When is a sensibility test useful or indicated?
When a patient has unlocalised or referred dental painTo aid in diagnosis between odontogenic and non‐odontogenic painTo confirm apparent radiographic periradicular pathology in the absence of any clinical signs/symptomsTo confirm pulpal status when there are clinical signs/symptoms but no apparent radiographic changesperiradicularlyTo discern between a periodontal abscess and an endodontic abscess & help confirm when a perio‐endolesion is suspectedTo assess the pulpal status of a tooth prior to crowning.Monitoring the success of pulp caps/ pulpotomies (ensuring that the pulp has not become necrotic)Monitoring traumatised teeth/ revascularization cases(usually over several months).Monitoring teeth following orthognathic surgery/ OS procedures/ facial fractures/ tooth transplantationTo confirm profound pulpal anaesthesia.
28
When is a sensibility test not indicated?
Electric pulp testers DO NOT interfere with pacemakers
29
Name 2 types of sensibility tests?
Thermal| Electrical
30
Name and explain 5 types of cold sensibility tests?
```Ice sticks (not could enough)Ethyl ChlorideEndoIce (TFE)EndoFrost (PBM)Dry Ice (very rapid sensory response)```
31
What are the pros and cons for a cold sensibility test?
Superior to Hot testColder the test more reliableCold stim causes a rapid outward flow of dentinal fluid:- test a delta fibres, respond to fluid movement, info extrapolated to consider pulp is vital
32
Name and explain 5 types of hot sensibility tests?
Warm Gutta percha (place vaseline first)Warmed instrumentElectrical heat sourcesRubber prophy cup (frictional heat)
33
What are the pros and cons for a hot sensibility test?
```Less useful than coldInitially stims A delta fibresProlonged heat stims C fibresExcessive heat can cause pulpal damageAn exaggerated and linegring response to heat is indicative of pulpitis```
34
Explain how the electric pulp tester works?
A battery operated device passes a small electrical current along the enamel prisms & dentinal tubulesto pulp tissueCurrent causes an ionic shift across the neural membrane inciting an action potential at the nodes of Ranvierin myelinated nervesThis stimulates the A‐delta fibresEPTs have a rheostat showing the relative amount of current applied on various scales
35
How to explain and complete the cold test procedure on a patient?
```Explain test and why it's necessaryPatient will feel coldIsolate and dry toothFind a control toothTweezers and cotton woolSpray cold stim onto wool and place onto tooth```
36
Where should you place the cold sensibility test stimuli on the tooth?
```On sound tooth structureIncisal edge or incisal 1/3 anteriorsMid third buccal surface premolarsMesio‐buccal cusp tip molarsHold pellet in place until the patient feels the stimuli or for a few seconds if no response```
37
Describe a normal pulpal reaction to a cold stimuli?
A sharp, sharp cold/pain sensation which| immediately ceases when the stimuli removed
38
Describe a pulpitis reaction to a cold stimuli?
A severe, prolonged, exaggerated response to cold
39
Describe a non-responsive reaction to a cold stimulus?
Pulp necrosisPrevious pulpotomy or previous pulpectomyFalse negative
40
How to explain and complete the electric pulp test on a patient?
Explain procedure and why it is necessaryPatient may feel tinge or warm sensationDry and isolate tooth + control toothPlace interprox celluloid strip where requiredPlace conducting interface medium on toothPlace tip of EPT on conducting medium and patient completes circuit by earling the lip clip or touching the probeIncrease current slowlyLet patient respond at pre-pain sensation
41
Where should you place the electric pulp tester on the tooth?
On sound tooth structureIncisal edge or incisal 1/3 anteriorsMid third buccal surface premolarsMesio‐buccal cusp tip molars
42
Describe a normal pulpal reaction to an electric pulp tester?
Sharp warm/hot/tingle or throbbing sensation which immediately ceases when stimulus removed
43
Describe a pulpitis pulpal reaction to an electric pulp tester?
A severe prolonged exaggerated response
44
Describe a non-responsive pulpal reaction to an electric pulp tester?
Pulp necrosisPrevious pulpotomy or previous pulpectomyFalse negative
45
What are the 2 reasons for a false +ve result for a sensibility test?
Anxious or young patient| Multirooted tooth
46
What are the 8 reasons for a false -ve result for a sensibility test?
```Incomplete root developmentTraumatised toothOrthodontic tooth movementHeavily restoredPulpal obliterationPeriodontal disease (decreased intensity of pain response to cold)Pre-medicationsPsychosis```
47
Name 1 reason for a false -ve electric pulp test result?
Improper use/technique
48
Name 5 reason for a false +ve electric pulp test result?
```Improper use/techniquePus in canal, as it can conduct to periapical tissuesMetal splintsBridgesOrtho arch wires```
49
What is the definition of a periradicular lesion?
Develop near the tips of root (where canal communicates with periodontium via apical foramen)
50
Where is a inflammatory periodontal lesion usually found?
Emerge at other anatomical or iatrogenic openings:- lateral aspects of root- furcations of multirooted teeth
51
How does apical periodontitis develop?
Following pulp tissue breakdown and the emergence of root canal infectionCan be symptomatic or asymptomaticBone resorption part of process
52
Explain how an RCT can be used to treat apical periodontitis?
Eliminate bacteria via RCT:- active inflammatory lesion subsides- bone regeneration takes place
53
Name 3 microscopic level different structural frame-works of apical periodontitis?
Apical granulomaApical abscessApical cystClinically and radiographically these histopathological entities cannot be distinguished from each other or recognized
54
What is the definition of an apical granuloma?
Consists of an inflammatory lesion dominated by:- Lymphocytes,- Macrophages and- Plasma cellsNumerous fibroblasts and connective tissue fibres usually present- + many capillaries.Around the edge an encapsulation attempt may often be foundThe epithelium originates from the epithelial cell rests of MalassezInfluenced by cytokines & growth factors released in the inflammatory processthe normally resting cells divide and migrate.- They may form more or less continuous- Random course- May also become attached to the root surfacePolymorphonuclear leukocytes are found in varying numbersAbscess formation can be a transient or persistent event within anexisting apical granuloma
55
What is the definition of an apical abscess?
Pus within the lesionAbscess formation = cellular dynamics within apical granuloma or direct outcome of an acute primary infectionHigh influx of PMNs (with high phagocytic activity of PMNs)PMNs die and release tissue-destructive elementsCT are degradedTissue in centre of lesion liquefiedCOntinuum exists between apical abscesses and apical granulomas
56
What is the definition of an apical cyst?
```Epithelium-lined cavityContains fluid or semi-solid materialSurrounded by CT:- infiltrated by mononuclear leukocytes and PMNs- cavity lined with stratified squamous epithelium- originates from epithelial rest of Malassez- can be lined with ciliary epitheliumLining can be be:- continuous- disrupted- completely missingSome cysts never become steady (consume bone or slowly expand)```
57
Explain the nutritional deficiency theory for apical cyst formation?
Assumes that epithelial proliferationresults in an epithelial mass that is too large for nutrients to reach its core,resulting in necrosis and liquefaction of the cells in the center. PMNs areattracted by the necrotic material, which, together with tissue exudate,result in microcavities that eventually coalesce to form the cystic cavity
58
Explain the abscess theory for apical cyst formation?
Assumes that tissue liquefaction occurs first, at thecentral part of an abscess. The peripheral aspect of the cavity is later lined by proliferating epithelium, owing to the inherent nature of epithelial cells to cover exposed connective tissue surfaces
59
Why do the size of radicular cysts slowly increase?
Increased osmosis leading to passage of fluid from the surroundingtissue into the cyst lumen is likely to occur owing to breakdown ofepithelial and inflammatory cellsRelease of bone‐resorbing factors from mononuclear leukocytes present in the cyst wall,including interleukins, mast cell tryptase and prostaglandins.
60
What are the causes for apical periodontitis?
Most AP is due to microorganisms within the RC. Other occasionalcauses include trauma, occlusal trauma, foreign body reactionBacteria in infected necrotic pulps predominately obligate anaerobes.Different microorganisms display differing abilityto survive in the root canal systemMore likely thata community of microbes existsBiofilms form in RCs. Biofilms protect bacteria from being destroyed
61
Name 6 microbial causes of primary apical periodontitis?
```Carious lesionsCracksTraumatic exposureAccessory canalsExposed dentinal tubulesPeriodontal pockets to the apical foramen```
62
Name 3 factors of selective pressures for microbial invasion of apical periodontitis?
NutritionOxygenMicrobial interactions
63
Name 6 types of bacteria present in primary root canal infections?
```- Spirochetes• Fusobacteria• Actinobacteria• Firmicutes• Proteobacteria• BacteriodetesNo more than 10 per canal and more are negative and are mostly anaerobic```
64
What is a reason for persistent Apical periodontitis?
Microbes remaining within the canal system
65
What are the survivability characteristics for E. faecalis?
Possesses a “proton pump” which allows it to survive in high pH (i.e. can survive calcium hydroxide)• Can survive in mono‐infection• can survive long periods of low/no nutrition
66
Explain the root canal response to canal instrumentation cutting BVs in the PDL or bone?
This activates intrinsic and extrinsic coagulation pathways.• Contact between the Hageman factor and:• collagen of basement membranes,• enzymes such as kallikrein or plasmin,• endotoxins from inflamed root canalscan activate the clotting cascade and the fibrinolytic system.• Fibrinogen molecules and fibrin degradation products are released during fibrin proteolysis by plasminthese release fibrinopeptides• Trauma to the periapical tissues during RCT can also activate the kinin system• This will then activate the complement system.• C3 complement fragments found in periradicular lesions.• Products released from the activated systems contribute to the inflammatory process and causeswelling, pain, and tissue destruction.
67
Name the 7 factors needed for a tooth to be healthy?
```comfortable to the patient• not tender to percussion or occlusal pressure• not sensitive to palpation.• Free from sinus tracts• Free from swelling• Has no painful symptoms.• Has normal pocket‐probing depths:• pocketing may also imply a sinus tract drainage along the periodontalligament space.```
68
Name the 5 different types of root canal infections?
asymptomatic apical periodontitis (chronic apical/periradicular periodontitis),• symptomatic apical periodontitis (acute apical/periradicular peri‐ odontitis),• acute apical abscess (acute periradicular abscess),• chronic apical abscess (chronic periradicular abscess, suppurative apical/periradicularperiodontitis),• condensing osteitis (focal sclerosing osteomyelitis, periradicular osteosclerosis, sclerosingosteitis, sclerotic bone).
69
What are the radiographic findings for a normal periapical condition?
unbroken lamina dura• distinct periodontal ligament space of normal width,comparable to adjacent and contralateral teeth.
70
What is the definition of an asymptomatic apical periodontitis?
is longstanding periapical inflammatory• Has radiographically visible periapical bone resorption• has no clinical signs and symptoms.• Is associated with a tooth with a non‐vital pulp (untreated or treated).It might be suspected from a carefully taken disease history in cases when patient hasexperienced a prior painful event.
71
What is the definition of an symptomatic apical periodontitis?
Symptomatic apical periodontitis may develop as a direct consequence of thebreakdown and infection of the pulp within a previously healthy periapical region.• It reflects a response to an initial exposure of the periapical periodontium to bacteria• or their products emerging from the infected root canal.• may also appear in a tooth with previous asymptomatic apical periodontitis.• Can be a natural shift in the balance previously established between the bacteria andthe host or occur in response to endodontic treatment (endodontic flare‐up).• The typical symptoms include:• pain (aching)• may become severe or even unbearable.• usually tender to percussion• mucosa and bone overlying the apical area sensitive to palpation.• premature occlusion
72
What is the definition of an acute apical abscess?
Characterized by:• rapid onset,• spontaneous pain,• tenderness of the tooth to pressure,• pus formation• swelling of associated tissues.• Initially, may be extremely painful, (pressure builds up in bone or periodontal space).• Cortical plate may perforate and pus will accumulate under the periosteum producing a most severe painful condition.• Only with the perforation of the periosteum will the pus be able to drain and allow pain to subside.• Then a tender local swelling will appear.• Sometimes, natural drainage will be established within a few days by perforation of the covering tissue.• In other cases, the swelling will remain for some time before it gradually subsides.• Drainage of an apical abscess will take the “path of least resistance”• thickness of overlying bone• Following penetration of the bone and periosteum, drainage will often be visible:• in the oral cavity but it may also occur• into perioral tissues or• into the maxillary sinus.
73
What is the definition of an chronic apical abscess?
Typical feature = sinus tract.• Drains into:• mouth or• extraorally through the skin• A sinus tract may establish exit with drainage• into the gingival sulcus,• in a periodontal pocket or• in a furcation area• MUST be differentiated from periodontal disease and from a pocket associated with avertical root fracture.• A sinus tract may also lead into the maxillary sinus and cause unilateral chronic sinusitis!• Most commonly associated with an apical radiolucency (but not always)• It is asymptomatic (or only slightly symptomatic)• patient often unaware of its presence.• This may last as long as the sinus tract is not obstructed.
74
What is the definition of cellulitis?
symptomatic edematous inflammation• associated with diffuse spreading of invasive micro‐organisms through connective tissue and fascial planes.• Its main clinical feature is diffuse swelling of facial or cervical tissues.• Cellulitis usually follows an apical abscess that penetrated the bone,• allows the spread of pus along paths of least resistance.• Spreading infection may or may not be associated with systemic symptoms such as fever and malaise.• Since cellulitis is usually a sequela of an uncontrolled apical abscess, other clinical features typical of anapical abscess are also expected.• Spreading of an infection into adjacent and more remote connective tissue compartments may, rarely, resultin serious or even life‐threatening complications.• Cases of Ludwig’s angina• orbital cellulitis• cavernous sinus thrombosis• and even death from a brain abscess• originating from a spreading dental infection have been reported.
75
What is the definition of condensing osteitis?
diffuse radiopaque lesion• believed to represent a localized bone reaction to a low‐ grade inflammatorystimulus• usually seen at an apex of a tooth (or its extraction site) in which there has been alongstanding pulp disease.• It is characterized by overproduction of bone in the periapical area, mostly aroundthe apices of mandibular molars and premolars that had long standing chronic pulpitis.• The pulp of the involved tooth may be vital and chronically inflamed or may havebecome necrotic with time, leaving the radiopaque area.• Normally the condition does not prompt treatment• unless the pulp necrosis.• The radiopacity may or may not disappear after endodontic treatment or toothextraction
76
How are the periodontium and pulp connected?
Natural communications| Pathological and iatrogenic communications
77
As the periodontium and teeth develop, name the 3 natural avenues communication between pulp and periodontium?
Dentinal tubulesApical foramenAccessory canals
78
What can cause the dentinal tubules to become exposed?
DevelopmentalDiseasePeriodontal surgeryTraumatic injury
79
Describe the 4 types of CEJ morphology?
I: cementum over enamelII: edge edge cementum and enamelIII: gap between cementum and enamelIV: enamel over cementum
80
What is the definition of the apical foramen?
Principle route of communication between pulp and periodontiumPulpal inflamm can cause a localised inflammatory reactionMay be exposed due to severe loss of attachment
81
What is the definition of lateral canals?
Found apicallyCOntains CT and BVsDon't extend full width of dentine
82
What is the definition of a furcal canal?
All teeth with furcation involvement can potentially have exposed furcal canalsLesions suggested radiographically may be due to infectious products from a necrotic pulp diffusing down a furcal or lateral canal
83
What teeth to test for exposed furcal canals?
Sensitivity test:- Lower 46,36 (DL root)Upper and lower premolars (1-3 roots)Canines (2 roots)
84
What is the definition of a developmental malformation?
Palatogingival grooveUsually maxillary lateral incisorsIf epithelial attachment is breached, grooves becomes contaminatedSelf-sustaining infrabony pocket developsLoss of attachment can quickly extend to apical foramenDifficult to treat as scaling and RSI does not work
85
How to drain an endodontic abscess?
Insert a GP cine and radiograph| Can drain through the PDL space to the sulcus
86
What is the classification system for perio and endo lesions?
2017 World Workshop| Periodontitis associated with endodontic lesions
87
Explain the clinical examination for a possible endo or perio lesion?
PalpationPercussionpocket probingMobilitySinus or pus draining through PDLIf sinus is present, palpate to see if dischargingIf so, insert gutta percha cone and radiograph
88
Explain the diagnosis procedure for a possible endo or perio lesion?
Special testsTo differentiate between perio and endoSensitivity testHigher false positives in teeth with advanced periodontitisIf perio only tooth will respond to sensitivity testingUse 2 tests to increase reliabilityTest cavities to differentiate between perio and endodontic pathosisBoth perio and endo affecting tooth form a perio-endo lesionCharacterised by CAL, bone loss and periradicular pathology
89
What symptoms should I suspect with a perio-endo lesion?
```Hisotry of symptomsHistory of surgerydeep pockets (average root lengths)furcationPus exuding from deep pockets or swellings```
90
Explain the plan of action for a perio-endo lesion?
```Gather history and clinical information (endo and perio exam)2 Sensitivity testsRadiograph periapicalMake diagnosis Or further testing```
91
What is the treatment plan for a perio-endo lesion?
Retain toothExtraction (vertical and horizontal bone loss)Non-surgical endo/perio treatResectionElim diseased rootVisible with fixed prosthesis (high smile line)Buccal recession around implantConsider condition for potential abutment teethIncreased plaque, CAL and caries with RPDs
92
Explain the process of non-surgical endo and perio treatment?
Endo first and then perioCementum and intact PDL fibres may persist, can regenerate after perio treatmentPerio straight after endo, destroy fibres form long JE
93
Explain the process of root resection?
Allows functional retention of a multi-rooted toothRemove 1 or more rootsUse for furcated max molarsAlways RCT first before resectionAfter treatment, cuspal coverage restorationImportant to remove any dentinal overhangs
94
Name the 7 indications for root resection?
```Root fracturePerforationRoot cariesRoot resorptionSevere periodontal diseaseGrade II or III furcationFailed endodontic treatment```
95
Name the 2 contraindications for root resection?
Medical/physical issues| Fused roots
96
How success are root resections?
62-100% success over 5-13 yearsResected teeth have better outcome with regular perio maintenance and Fl application1:1 root:crown ratio is minimum acceptableLong term tooth retention requires 50% bone supportResected for perio better than non-perio
97
What is the definition of regeneration?
Aims to regenerate lost periodontal structuresDeep narrow defects favourableendo firstRetract flap, scale, RSI, removal granulation tissue, type defect, bone graft and resorbable membrane77.5% success over 5 years
98
What is the prognosis difference between single and multirooted teeth?
Better for single rootedMore success for perio than endoDeep narrow pockets good prognosis
99
Name 7 factors does endo success depend on?
Reaching WLDisinfecting full canal lengthKeep all RCT material within root canalsDense obturation with no voids within 2mm radiographic apexHaving enough dentine to achieve ferrule effectAdequate coronal sealCuspal coverage
100
Name 7 factors does endo success depend on?
```CALStabilisation of perio diseaseReduction of perio pocket depth and lack BOPEffective perio maintenancePresence of furcationMorphology of lesionSufficient bone```
101
What is the definition of apical periodontitis?
Bacteria in the root canal system
102
Why to perform root canal treatment?
Remove/reduce the bacteria to an undetectable level
103
What is the best method to reduce bacteria in root canals?
C&S + NaOCl + one week later Ca(OH)2
104
What evidence supports root canal treatment to aim for the apex of the root?
Best amount of healingOverfilled teeth have persistent inflammationSjorgen:- 0-2 mm 94%- > 2mm 68%- overfilled 76%Aim to fill between 0.5-2mm from the apex of the root
105
Where is the apex of the root found?
0.5 to 0.65 mm in elderly 0.59 mm0.72 mm0.8 mmApex changes in necrosis cases compared to normalChanges in shape change the apex
106
What is the definition of a F-flex file (Kerr)?
Rhombus stemRemove debris by increasing clearance between file and dentine wallSharp rhombus angle improve cut efficiencyFrom 6-gauge to the 80-gaugeTwisted
107
What is the definition of a Hedstroem file?
Drags large amounts of fabric in its traction cutHelicoidal shapeTurned instrumentCut in one direction only, of retraction, due to positive inclination of their groves
108
What motion is good for a SS file?
Bend to get round corners
109
What motion is good for NiTi files?
Straighten it
110
Explain the crown-down pressureless technique for root filing?
Rotate straight file twice form larger to smaller sequence until 16mmCoronal flare with GGEstablish provisional WL 2mm short of apexRotate stright file at WLFinish apical prep at WL with file 2 sizes larger than first file to reach WL
111
Explain the process of root filing for a Ni Ti file?
Used for crown-down sequenceEstimate working length from pre-OP radio, subtract 3mm from this length - use this new length to work to for the coronal 2/3 prepInitial negotiation by hand using ISO files 08-20 passivePrecurveUse lubricantTake S1/2 to 2/3 canal length turning clockwise until snug then pull from canal and cleanIf further coronal flare required or relocation orifice use SX to 2/3Length (WL minun 3mm), turning clockwiseDetermine WL with apex locator and take ISO 09-20 to WLS1 then S2 to WL turning clockwise as aboveF1 to lengthGauge the size of the apical constriction using a 20K file, if this fits snugly, the prep can be complete at this stageHowever, generally the apical size needs to be at least 30 to allow irrigation into the apical 1/3Take F2 to WL and gauge the foramen using a 25 K fileIf this fits snugly, the prep can be completeOr Take F4 to WL and gauge with 30K file, i fits snugly can be completedUse the same sized paper points for during the canal and same sized GP cone for obturating
112
Why to use F3 Ni Ti files?
150mm bacteria
113
What % does NiTi superflexible show for elastic ability?
8%
114
How does NiTi superflexible root file become to flexible?
Martensite heated becomes Austenite and then cools and changes structure, but when deforms reverts back
115
Name and describe 3 5th generation NiTi root file?
Centre of mass or centre of rotation is offsetProduces a mechanical wave of motion that transverses along the length of the fileImproved cutting and removal of debris by increasing cross-sectional spaceReduce engage between file and dentineRevo SProTaper NextOne Shape
116
What is the definition of 'Hot Pulp'
Inflamm changes within the pulp progressively worsen as a carious lesion near the pulpChronic inflammation is an acute exacerbationInflux of neutro and release inflamm mediators (glandins and IL)Proinflamm neuropeps:- SubP- bradykininSensitive the peripheral nociceptors within the pulp
117
What is the definition of an endodontic emergency?
As pain and/or swelling, caused by various stages of inflammation or infection of the pulpal and/or periapical tissues
118
Patients who present with pulpal pain, what are the differential diagnoses?
```Pulpal pain:- irreversible- reversible pulpitisPeriradicular pain:- symptomatic radicular periodontitis- acute periapical abscessCracked/fractured toothPain from current endodontic treatment:- NaOCl accidentIatrogenic damageRecent restorationsHighly filled teethOverfilled RC systemRoot fracture```
119
What is the definition of non-odontogenic pain?
```No aetiologyNo caries, trauma, fractures or failing restorationsPain not relieved by LaBilateral or multiple tooth painLong standingUnresponsive to treatment```
120
Name the 3 non-odontogenic pain discriminative symptoms?
Burning or electrical pain| Pain increases during different emotional states
121
Name 4 types of non-odontogenic pain?
MigraineCluster headacheParoxysmal hemicraniaSUNCT
122
What is the definition of an emergency pupotomy?
Effective for symptomatic irreversible pulpitisReturns for pulpectomy/prepLess challenging that pulpectomy
123
Explain the procedure for an emergency pulpotomy?
LARubber damOpen pulp chamber and irrigate with NaOClAmputate coronal stump with slow speed or spoon excavator Don't enter canals yetIrrigate with NaOclDry with dampened cottonSeal CaOH into pulp chamberCover with some cotton covered by Cavit + GIC/RMGICGive adviceReturn for RCT
124
How does a pulpotomy relieve pain?
ALters pulp haemodynamic and interstitial tissue pressure, deceases local tissue pressure and decreases inflammatory mediators, severs terminal endings of nociceptors
125
What are the indications for a pulpectomy?
Non-vital toothsymptomatic PRPAcute periapical abscessPulpotomy will not relive sufficient pain
126
What is the definition of pulpectomy?
Complete pulpal extirpation and debridement of the RCS
127
How does a pulpectomy relieve pain?
Reduces bacterial products in the apical 1/3 of the canalsDecreases the nociceptive activity in the periradicular tissueSubstantial decrease in pain between 24-36 hrs
128
What is the definition of an acute apical abscess?
Develop from a symptomatic or asymptomatic PRP or a chronic apical abscess
129
How does an acute apical abscess form?
Bacteria that egress infected RCS and invade periradicular tissues to establish an extraradicular infection and evoke purulent inflammationDom by anaerobic bacteria12-18 bacteria compared to 7-12 in root canals
130
What are the clinical symptoms for an acute apical abscess?
```PainTTPTender to palpate buccal sulci+/i mobility, local swelling and facial space involvementSystemic manifestations:- fever, headache and nauseaRadiographically:- possible widened periodontal ligament spaceSensibility testingPeriapical abscess = non-vital toothPeriodontal abscess = vital tooth```
131
Where does the exudate form an acute periapical abscess exit?
Through the path of least resistance| Result in local swelling where it exists through the alveolar bone, discharged via the PDL or spread into tissue spaces
132
What are the treatment options for an acute periapical abscess?
Remove source of infection or relieve Pa through drainageExtractPulpectomy + drain via RCSIncise and drainExudate can be removed via RCS, can relieve pain
133
Explain the process of a pulpectomy and drainage for an acute periapical abscess?
Access to RCS to WL, if no drain, take 08 or 10 K file through apical constriction, can enable drainageIf not irrigate and dress as usualDO NOT leave open (can cause delayed healing and later flare upsCan become heavily infectedPersistent drain - allow patient to wait 30 minsDress with CaOH and seal access
134
How can acute apical abscess form fascial space infections?
Bacteria from RCS enter periradicular tissue and the immune system is unable to suppress invasion, they will eventually show symptomsCan be found in vestibule or into fascial space
135
What is the definition of the fascial infection submandibular space?
Potential space between the mylohyoid muscle superior and platysma inferiorlyMolar tooth
136
What fascial spaces give a Ludwig's angina?
SubmentalSublingualSubmandibularCan advance into pharyngeal and cervical spaces
137
What is the definition of Ludwig's angina?
Life threatening cellulitis advance into pharyngeal and cervical spaces resulting in airway obstruction
138
What are the treatment options for Ludwig's angina?
```Antibiotics + endodontic treatmentAggressive incision for drainageRelieve PaExtractionRCTIncision/drainage```
139
How to provide pathway for drainage to prevent spread for Ludwig's angina?
Decompression of increased pressure associated with oedemaPain reliefImproves circulation to area, allowing better deliveryExtraoral drain may be required
140
Explain how an RCT will treat Ludwig's angina?
Phago kill bacteriaLeukocytes influx stopNeutrophilic leuko die of apoptosisMacro clean up mess
141
When can you prescribe antibiotics for an dental infection?
```Pulpal necrosis: plus- diffuse swelling- drainage can't be achieved- systemic involvement- fever, malaise, trismus or lymphadenopathyNeeded for RCT with post```
142
What are the post-OP advice for endodontic treatment?
```Check for sharp bites and normal biting feelUsual LA adviseInjection site may be tenderGingiva sore or bleedingTooth to be tender```
143
How can NaOCl accident occur during endodontic treatment?
```Extrusion of irrigant into periradicular tissueOccur when:- needle wedges in canal- tooth wide open foramen- immature apex- resorbed apex```
144
What are the symptoms of NaOCl accident?
```Sudden, prolonged sharp painRapid and diffuse swellingHemorrhagic reactionOedemaBruisingTissue necrosis```
145
What is the definition of a perforation?
Iatrogenic by errorBlood seen during RCTAcute inflammatory reaction will occurPresent with perio abscess (pain, swelling and pus draining via PDL)
146
What is the definition of a 'flare-up'?
```Acute exacerbationSignificant increase in pain and swellingSudden exacerbation of a previously symptomless periradicular lesionNeed emergency appointmentLow occurrenceNeed active treatmentIrrigate canalsDrainPre-emptive analgesia can be successful```
147
Name 5 causes for abscess flare-ups?
```Apical debris extrusionIncomplete instrumentationSecondary intracanal infectionLost provisional restorationsNon-microbial causes```
148
Name 5 risk factors for flare-ups?
```GenderSystemic diseaseDiabetesPre-Op painTooth type (5,6,7)Necrotic teeth```
149
Name 5 ways to prevent flare-ups?
```Pre-emptive analgesiaRubber damCrown down sequenceAchieve WL and irrigate passivelyClear post-OP instructions```
150
Explain the process to treat flare-ups?
```AnalgesicsCheck canalsEnsure correct WLIrrigate to apical 1/3Drainage via RCSSWelling present, consider incision and drainageIrrigate a lotRedress with CaOH + GICCheck occlusion```
151
Name 5 causes of pain immediately after obturation?
```Over-instrumentOverfillIrritated periradicular tissuePerforationRoot fracturesCold lateral compactionRestoration in supraocclusionPoor occlusion```
152
GS treatment for reversible pulpitis?
Remove cause:- defective filling- caries
153
GS treatment for symptomatic irreversible pulpitis?
Emergency pulpotomyPulpectomyextraction
154
GS treatment for necrotic pulp and symptomatic periradicular periodontitis?
Pulpectomy| Extraction
155
GS treatment for acute apical abscess?
Pulpectomy and drainage via RCSIncision and drain via STExtractionAntibiotics if systemic
156
Why should you routinely remove existing restoration prior to RCT?
TO check for:- routes of microbial ingress (caries, cracks and defective margins)- quality and quantity of dentine remaining- investigate the tooth
157
What factors to consider when thinking whether a tooth is restorable?
Perio statusGeneral factorsProsthodontic prognosis (seal)Endodontic prognosis
158
What are the requirements of a tooth to be suitable for endodontic treatment?
```Pulp chamberRoot canals visibleRoot curvatureRoot lengthApical closurePrevious RCTRestorationLocation and Position```
159
How can size of pulp chambers affect the complexity for an endodontic treatment?
Size decreases with age and due to secondary/3rd dentineSmaller chamber is more difficultincreased iatrogenic errorsCalcification can impede access into RCS
160
How can pulp obliteration affect the complexity for an endodontic treatment?
Occurs with increased age and 2nd/3rd dentine depositsIn response to traumaRadiolucency = canalIf RCS not present, RCT not really possible
161
How can root curvature affect the complexity for an endodontic treatment?
Curves or SH shaped curve, increase risk of file mishaps such as breaking or perforations
162
How can root length affect the complexity for an endodontic treatment?
Can cause open apexIdiopathic root resorptionNeed sufficient working lengthCan be longer than expected
163
How can tooth position affect the complexity for an endodontic treatment?
Tilted, rotated and retroclined can make access difficult
164
What are the contraindications for endodontic treatment?
Limited accessunrestorable toothLong term functionless or non-strategic toothSevere, progressive perio diseasePatient can't lie supine or still for long enoughIf too difficult REFER
165
Name 10 periodontal factors which can affect endodontic treatment?
```Presence of periodontitisBOPOHCariesLoAPocketsFurcationsBone supportUnusual anatomyRestoration margins (caries/fracture extending subgingivally)If tooth margin below gingiva - crown lengthening```
166
What is the definition of a perio-endo lesion?
Exhibits 2 conditions concurrentlyMarginal LoAPeriradicular periodontitis (PRP)
167
Name the 3 ways in which a perio-endo lesion can arise?
Tooth have noth advanced perio disease and coincidentally develop pulpal necrosis + PRP at the same timeTooth with advanced perio disease + LoA extending the apical foramen (causing pulpal necrosis and develop PRP)A tooth develop necrotic pulp + PRP, infection can cause perio pocket
168
What is the definition of the Ferrule effect?
A metal ring or cap intended to embrace the tooth structure cervically to achieve root strengthening and prevent shattering the root2mm H1mm W
169
What is the definition of a coronal seal?
Quality of the coronal restoration at preventing microbes from gaining access to the RCSSeal fail = RCT failFilling/Crown/Bridge
170
Describe the 5 stage pre-OP assessment for an endodontic treatment?
1. Diagnosis2. Assess restorability and study radiographs3. Plan access4. Dam5. Magnification
171
Describe the access cavity shape and location for a canine?
1 oval shaped canal so the outline of the access cavity is an oval
172
Describe the access cavity shape and location for a maxillary 1st premolar?
2 canals, may be connected by an isthmusGives a figure of 8 type shapeOutline form of access should reflect the figure of 8 shapeOval like shape
173
Describe the access cavity shape and location for a mandibular molar??
3 canalsOutline form of access cavity reflects where you expect to find these within the pulp chamberRhombus like shape
174
Name 8 requirements for the access cavity?
```Prevent coronal leakage during RCTCreate reservoir for irrigationGood retention and thickness for temp restoLocate all canal entrancesAll seen from one viewGive straight line access to apical 1/3Remove all pulp chamber roof and coronal pulp tissuesConserve as much dentine as possible```
175
Where to create the access cavity for an anterior tooth?
Lingually| To achieve straight line access whilst reducing aesthetic and restorative concerns
176
Where to create the access cavity for a posterior tooth?
Occasionally| To achieve straight line access whilst reducing aesthetic and restorative concerns
177
What bur helps protect the floor of the pulp chamber?
Safe ended/non-cutting burs| Endo Z bur
178
Name the 2 burs to be used during an endodontic procedure?
Long fissure bur for initial outline formOne the root of the pulp chamber is enteredNon-cutting/safe ended tip bur
179
How to make sure that every canal has been identified?
```NaOCl will bubble over canal entrancesSharp DG16 robe to pickUse dye (methylene blue)Endodontic ultrasonicLong neck or gooseneck burs```
180
Describe the root apex?
Apical constriction is accepted as being 1mm short of the radiographic apex
181
Give a description of a Gates Glidden rotary instrument?
Rotary instruments• In the past, used routinely for ‘coronal flare’• BUT can only be used in straight portions of the canal• Side cutting instruments/ non‐ end cutting tip• Different sizes availableIf not used carefully GG can remove far too muchdentine, weakening tooth and potentially perforating- Superseded by NiTi files
182
Explain how a ledge can cause problems?
A ledge is internal transportation of the canal• Occurs when working short of length with straight files• Avoid by ALWAYS precurving• Ledges can sometimes be bypassed but difficult
183
What is the definition of apical transportation?
Transportation of the apical foramen changes the shape of theforamen• This makes it more difficult to fill/seal & also fails to provideresistance for packing of gutta‐percha• Can easily overfill- Avoid crown-down sequence
184
What is the definition of zipping the root canal?
The outer side of the curve is over‐enlarged & the inner side of the curveunder‐prepared• Transports the canal• The narrowest part of RCS where zippinghas occurred is called an ‘elbow’• This hour‐glass shape makes satisfactoryobturation of the apical third very difficult• Avoid by using ss files only for guide path &then swap to niti’s
185
What happens when you create a perforation in the root?
Can occur where an end‐cutting file is used, or overzealous preparation of a ‘zipped’ or blocked canal.• A false canal is cut through the radicular dentine andinto the periradicular tissues• If this happens during RCT, there will be bleedinginto the canal +/‐ patient c/o pain• Radiographs using parallax shift can help identify• Electronic apex locators help identify• Dental operating microscope to identify & repair• Avoid by using non‐end cutting files whereverpossible, work passively, never force a file or bur intothe RCS
186
What is the definition of torsional fatigue?
Occurs when the instrument tip is locked in the canal and the instrument above the jammed/locked portion continues to rotate. This causes it to fracture• This type of fracture is due to too much torque on the file• The torque generated on a file during canal preparation depends on:• The contact area of the file with the walls of the canal• Using a crown‐down approach reduces torque• Using a light pressure on the files reduces torque
187
What is the definition of flexural fatigue
Cyclic loading leads to metal fatigue| • As all endodontic files are single use in the UK this is unlikely to happen
188
Name the 7 advantages of NiTi files?
```Superelasticity - Increased flexibility in larger sizes and tapers - 3 x more than ss• Increased cutting efficiency• Faster preps• Less iatrogenic damage• Stays centered in canal• Less transportation• More predictable result• BUT more expensive```
189
What are the 2 main properties of NiTi are useful for endodontics?
Superelasticity with shape memory/recovery| • High resistance to cyclic fatigue
190
Name 1 commercially available NiTi system?
ProTaper
191
Name the 8 files of the ProTaper system?
```3 shaping files - S files: coronal and mid third- SX- S1- S25 finishing files - F files: apical third- F1- F2- F3- F4- F5```
192
Give a description of shaping file SX and how it is used?| length and tip diameter
```No coloured band – is ‘gold’ shank• Length 19mm• Tip diameter 0.19mm• Taper apically 3.5%• Taper coronally19%• Can be used before or after S1 and S2• Creates a large amount of coronal flare• Hand version use by turning clockwise• Rotary version can be used to relocate canalorifices• Use ‘brushing’ motion```
193
Explain how to use a SX shaping file and their specific danger zones?
Rotary ProTapers can be used very effectively to flare canals using abrushing action.• ALWAYS use carefully to avoid over‐preparing/over‐’brushing’ in ‘dangerzones’• Danger zones = the distal surface of mesial & MB roots & mesial surface ofdistal roots etc (furcation areas)
194
Give a description of shaping file S1/2 and how it is used?| length and tip diameter
```S1 = purple handle• S2 = white handle• Tip diameters• S1= 0.185• S2= 0.20mm• 14mm cutting flutes• Partially active tips• to guide through debris• Tapers vary along length• increasing from a minimum of 2% attip to 11.5% at handle‐end• Use hand files by turning clockwise• Rotaries with a ‘brushing’ motion```
195
Explain the crown-down technique for endodontic procedures?
Coronal portion of canal prepared BEFORE WL verifiedIrrigation introduced early• Removes bulk of microbes early• Better tactile sensation• Less changes in WL• Reduces torsional loads on files reducing risk ofinstrument fracture
196
Explain the process of crown-down technique?
```Involves preparing the canal in 3 stages:• Creating a guide path• Prepare coronal 2/3• Measure EWL from radiograph – subtract3‐4mm. Set stoppers at this new length.• (find out the true/correct WL)• Prepare apical 1/3```
197
How to estimate the working length from a pre-OP radiograph?
```On R4 measure the digital radiograph byclicking on the ‘ruler’ symbol and thenclicking on the radiographic apex and theincisal edge.Then subtract 3‐4mm from this lengthThis gives the length to prepare thecoronal 2/3 to.```
198
Why is the guide path essential for endodontic treatment?
```Ensures canal is patent (notblocked)• Creates a path large enough for theNiTi file tips• Prevents tip binding & instrumentfractureWatchwind/twiddle a precurved10, 15, 20 K file in a wet canal +/‐lubricant paste to the coronal 2/3measurement```
199
How to create the guide path?
```With stainless steel filesyou are ready to start withthe niti ProTaper files• Set the silicone stops on the S1 & S2 files to the coronal 2/3measurement (EWL minus 3mm)```
200
What is the definition of the working length?
The working length is the distance from a coronalreference point to the point at which the canalpreparation & obturation should terminate.• The estimated working length is usually consideredas the distance in mm’s from a coronal referencepoint (eg incisal edge) to the radiographic apexminus 1mm
201
Explain using R4 how to estimate the working length of a RC?
```Open the pre‐opperiapical & selectthe ‘ruler’ symbolClick on the incisal referencepoint & around 1mm short of theradiographic apex. The PC willdisplay the length of this in mm’s.This is the EWLIf the canal appearscurved, click on thecurved point too to tryand get a reasonablyaccurate EWL```
202
What options can be used to establish an accurate WL?
- Radiographs• Electronic Apex Locator• Tactile sensation• Paper points
203
Explain how to use radiographs to find an accurate WL?
Use a size 15 ISO• Flexible K file• Use a sound, reproducible reference point• Usually the incisal edge or a cusp tip• Use paralleling technique with film holder• Ideally, the file tip should be 1‐2mm from the radiographic apexIdeally the file is not right at the radiographic apex as this is probably toolong• Radiographs are not accurate for identifying the apical constriction....we“guesstimate” the apical constriction is around 1‐2mm away from theradiographic apexDespite their limitations radiographs are far more accurate than usingpaper points or tactile sensation• Ideally use electronic apex locator +/‐ radiographic WL
204
What are the advantages for using a small <30 finishing file for apical third of the root?
Minimal risk of canaltransportation, extrusion ofirrigants or filling materials
205
What are the disadvantages for using a small <30 finishing file for apical third of the root?
```Little removal of infecteddentineIrrigation may not get to theapical third Interappointmentdressings may not get intoapical thirdMay make obturationdifficult```
206
What are the advantages for using a large >30 finishing file for apical third of the root?
```Removal of infected dentine& debris from the apical thirdAccess for irrigants andinterappointment dressingsinto the apical third```
207
What are the disadvantages for using a large >30 finishing file for apical third of the root?
```Risk of preparation errors& extrusion of irrigants andfilling materialsIf obturating with heatedtechniques, likely to get anoverfill```
208
What is the general rule when preparing the apical 1/3 of the root?
As a general rule, unless the apical 1/3 is prepared to a 30(F3),it will notbe possible to get irrigation into the apical l/3• Try to prepare all canals to a MINIMUM size of F3
209
Explain the step by step process of preparing the apical 1/3 of the root?
Prepare to WL using Finishing File 1• Place 20 Flexofile to gauge apical size• Prepare to WL using Finishing File 2• Place 25 Flexofile to gauge apical size• Prepare to WL using a Finishing file 3• Place a 30 Flexofile to gauge the apical size• If the 30 Flexofile is loose, repeat with Finishing Files F4 & F5 until correctapical size has been determined
210
What to do if the root canal WL is > than a F5 file?
If a canal is prep’d to F5 at working length:• Insert a 50 Flexofile to WL• Does it feel loose in canal?• If so, it is unlikely that gutta percha willsatisfactorily seal the canal.• This needs treated as an ‘open apex’• Mineral trioxide aggregate will need to beplaced to form an ‘apical stop’• Refer for completion of treatment with aspecialist• Dress meantime in usual way
211
How should you irrigate the >F5 canal?
×1 syringe sodium hypochlorite×1 syringe citric acid & leave in canal for 60 seconds×1 syringe sodium hypochloriteDry canal using absorbent paper points matched size
212
What to comment in the notes for a >F5 canal?
Make sure you have recorded the following in the patient’s notes:• The working length(s) (& what you have used to verify it)• The reference point(s) used for measurements• The size of the apical preparation i.e the final finishing file used• Eg. Canal prep’d to F4 at WL of 23mm (using EAL) from incisal edge mid‐point
213
Name 2 types f seals?
Hermetic| Fluid tight or bacteria tight
214
What is the definition of a hermetic seal?
Sealed against the escape or entry of air
215
What is the definition of a bacteria tight seal?
A more appropriate term as root canals are evaluated for leakage of fluid
216
Name 9 properties of an ideal obturating material?
```No shrinkage• No solubility in tissue fluids• Good adhesion/adaption to dentine• No water absorption• No tooth discolorationHandling• Radiopaque require > 3mm aluminum• Setting in an adequate time• Easy to apply and remove using heat, solvents or mechanicalinstrumentation```
217
Explain the main cold lateral compaction obturation technique?
Select a Master Apical Cone, (MAC) the same apical size asMaster Apical File, (MAF)• Measure cone to WL and place slowly into wet canal- to correct working length• Aim to achieve a frictional fit apically• There should be a definite stop when cone fits into placeMaster cones lack uniformity and can vary in tip size• Useful to take a cone-fit radiographDry canal with correct size of paper points measured to WL• Mix sealer and have spreader readyCoat MAC lightly in sealer• Insert into canal to correct WL• Use a slow pumping action to allow back-flow of sealerRemember that except for apical 2-3mm, the root canal will be much more tapered than the master gutta-percha cone• This space is fill by compaction of accessory cones that havebeen lightly coated in sealerInsert spreader with stopper:• 1-2mm short of WL with firm apical pressure (or asfar as possible when using (Protaper MAC)• Leave in place 10-15secs with light lateral pressureRemove spreader witha slight rotation, andplace accessory cone,lightly coated in sealerquickly into channelRepeat this process until no further accessory cones can be fitted• Take an obturation verification radiographat this stage• Removal and reobturation is easier if over/underfillCut off excess GP cones with a heated instrument (be careful notto touch patient’s lip) and compact the coronal GP firmly in a vertical direction using an endodontic plugger
218
What to do if the MAC is not within 1mm of prepared length?
Refining canal is required| • Using a smaller MAC
219
What to do if the MAC extends beyond apical foramen?
Lack of apical stop| • Use a larger cone
220
What restorations to place for the anterior teeth after obturation?
Light coloured composite resin in access cavity
221
What restorations to place for the posterior teeth after obturation?
Restoration depends on definitive restoration – crown / onlay• Seal access with amalgam or glass ionomer to prevent coronal leakage• Remove rubber dam• Check occlusion• Final radiograph
222
When should the definitive restoration be placed?
There is no need to wait for radiographic evidence of healing (6 mnth) beforeplacing definitive restoration, providing RCT is a high standard
223
How to gauge the apex of a root canal?
Gauge the size of the apical constriction using a 20K file, if this fits snugly, the prep can be complete at this stageHowever, generally the apical size needs to be at least 30 to allow irrigation into the apical 1/3Take F2 to WL and gauge the foramen using a 25 K fileIf this fits snugly, the prep can be completeOr Take F4 to WL and gauge with 30K file, i fits snugly can be completedUse the same sized paper points for during the canal and same sized GP cone for obturating
224
How to gauge the apex of a root canal?
Gauge the size of the apical constriction using a 20K file, if this fits snugly, the prep can be complete at this stageHowever, generally the apical size needs to be at least 30 to allow irrigation into the apical 1/3Take F2 to WL and gauge the foramen using a 25 K fileIf this fits snugly, the prep can be completeOr Take F4 to WL and gauge with 30K file, i fits snugly can be completedUse the same sized paper points for during the canal and same sized GP cone for obturating
