Description
In this collection we will review many important informations for dental students
Study Set Content:
Endodontics
Course Review
Enoch Ng, DDS 2014
o
GP Points
Standardized – same tip diameter and taper as files
Master cone should be same as MAF
Conventional – tip has one size, body a different size (FM – fine tip, medium body)
Fairly large tolerance in manufacture (size 40 point ranges from 35-45)
Sealer
o
Essential for success
o
Enhances seal and serves as filler for canal irregularities
o
May serve as lubricating agent
o
All types exhibit some toxicity – decreases after setting
-
Ideal properties
o
Tissue tolerant, soluble in solvents but not oral fluids, bacteriostatic
o
Slow setting, adhesive, non-staining, radiopaque
-
Types of Sealer
o
ZOE (gold standard) – Roth’s sealer, tubliseal, kerr pulp canal sealer
o
CaOH – CRCS, sealapex
o
Glass Ionomer – Ketac-endo
o
Resin – diaket, AH26, AH-plus, epiphany, RealSeal
o
MTA – iRoot Sp
-
Sealer placement
o
Hand file
o
Ultrasonic file
o
Lentulo spiral
o
Master cone
Obturation techniques
o
Pure lateral or vertical techniques rarely used
o
No clinical difference in normal canals
Warm technique – better canal adaptation but higher incidence of extrusion beyond apex
o
Increased compaction pressure does NOT significantly decrease apical leakage
o
No obturation material/technique will be successful without proper cleaning and shaping
-
Other Obturation Systems
o
Gutta-percha carrier system
o
Warm vertical compaction
o
Continuous wave
o
Hybrid technique
Endodontics
Course Review
Enoch Ng, DDS 2014
[Cold] Lateral compaction
Advantages
-
Good length control
-
Easier to adjust mid-obturation
Disadvantages
-
Difficult to fill canal irregularities (internal resorption)
-
Difficult in open apex cases
-
Limited in severely curved canal (poor spreader penetration depth)
-
Complete preparation
-
Dry and inspect for tissue removal and smooth, well-shaped walls
-
Check preparation flare (place MF finger spreader into canal – should go to within 1-2mm of CWL)
-
Select master cone (in relation to MAF), fit to working length, radiograph to confirm seated to length
o
If goes past CWL
Try another cone of same size (tolerance range)
Trim MC
Try larger size MC
-
Place sealer on master cone and seat MC into position
-
Use size MF or F NiTi spreader
o
Place finger spreader alongside master cone to within 1-2mm of CWL – compaction of apical GP
-
Use NiTi’s carefully – cannot be pre-curved, may buckle under pressure
-
Measure an accessory point matching size of spreader (or 1 size smaller) to length spreader was placed
-
Remove spreader, place accessory cone coated with sealer to length
-
Repeat until spreader no longer goes beyond coronal 1/3 of the canal
-
Take a pre-sear radiograph to ensure length and density of obturation is adequate
-
Sear off (200
o
C) and remove excess GP to level of CEJ with System B heated plugger
-
Apply light vertical pressure with pluggers – oppose GP’s shrinkage on cooling
-
Clean out excess GP with ^OH on microbrush/cotton pellet
-
Place final restoration/temporize
-
Take post-op radiographs
o
If canal was improperly prepared, spreader placement may have excess pressure and fracture the root
o
Must pre-fit pluggers to avoid excessive lateral pressure on roots
o
If canal is curved, NiTi finger spreaders create less stress and penetrate farther than SS spreaders
Goals of Obturation
-
Root canal fillings – completely homogenous mass fills prepared canal in all 3 dimensions
o
Presence of voids may provide leakage avenues and give way to bacterial regrowth/reinfection
-
Radiographic evaluation criteria
o
Length, taper, density
o
Removal of GP and sealer to CEJ level in anterior teeth, canal orifice in posterior teeth
o
Adequate temporary/definitive restoration
Removal of GP for post placement
-
Safest to remove with warm instrument
-
Removal does NOT affect obturation success, so long as apical 4-5mm remains intact
Coronal Seal
-
Root canal is not finished until final coronal restoration is placed
-
Full coverage indicated for posterior teeth
-
teeth with poor restoration resulted in more teeth with periradicular lesions than poor endodontic fills
Endodontics
Course Review
Enoch Ng, DDS 2014
Microbiology and Infection
-
Why – pulpal and apical disease
-
How – access, cleaning/shaping, canal disinfection, obturation, final restoration
Inflammation and Infection
-
Inflammation – SHaRP, loss of function – protective attempt by organism to remove injurious stimuli and initiate
healing process
-
Infection – pathologic condition where host is detrimentally colonized by non-host species, competition
between host and microorganisms
o
Primary pathology – bacteria
Other pathogens – viral, fungal
-
Microorganisms are the cause for pulpal and apical pathology
o
Germ free rats with pulpal exposure – no necrosis or infection
o
Normal rats with pulpal exposure – all pulp tissue necrotic with extensive bacterial spread
Bacteria must get into pulp to induce apical inflammation
Contamination via oral saliva
Necrotic tissue alone does NOT cause inflammation
Routes of infection
-
Pulpaldentin complex protected by dentin
o
Compromised by caries, cracks and fractures, restorative procedures, attrition/abrasion, enamel defects
-
Dentin tubules
Bacterial Diameter = 0.4-0.7um
DEJ
Near Pulp
Diameter
0.8um
2.5um
Number
15-20K
45-60K
o
May travel up to 400um into dentin in 3 weeks
-
Vital pulp – helps prevents infection
o
Outward dentinal fluid movement
o
Tubular contents – odontoblastic processes, collagen fibrils)
-
These factors not present in necrotic pulp – easier for bacterial invasion
o
During/after treatment
Bacterial/calculus/biofilm remnants
Leaking rubber dam, leakage/breakdown of temporary, delay in permanent restoration
Contaminated instruments, root canal filling material exposure
Bacterial Morphology
-
Gram +
ve
– thick cell wall peptidoglycan, teichoic and lipoteichoic acid
-
Gram –
ve
– LPS, thin peptidoglycan cell wall
-
Major endodontic pathogens are obligate anaerobes
-
Pathogenicity – ability of microorganism to CAUSE disease
o
Biofilm formation
– resists phagocytosis and antimicrobials
Cells firmly attached to a surface, enmeshed in a self-produced matrix of polysaccharides
Broader habitat range of growth, increased metabolic diversity and efficiency, protection, and
genetic exchange for antibiotic resistance
Neutralizing enzymes in biofilm, surface bacteria absorbing antibiotic
Bacteria in altered growth/stationary phases
Endodontics
Course Review
Enoch Ng, DDS 2014
-
Virulence – degree of pathogenicity of a microorganism
o
Capsules – protects against phagocytosis
o
LPS/endotoxin
– stimulates overproduction of inflammatory response
Fat and sugar chain, binds to blood proteins which bind to macrophages who release
inflammatory mediators
o
Enzymes – degrade host tissue
o
Ammonia, hydrogen sulfide – tissue toxins
o
Fimbriae – promotes adherence to tissues
o
Extracellular vesicles – stimulate immune response from host
o
Antibiotic resistance – through gene transfer
IDing Bacteria
Culturing
Advantages
Disadvantages
-
Assess viability of microbes
-
Low cost
-
Unable to grow many bacteria
-
False negatives
-
Low specificity and sensitivity
-
Technique sensitive
-
Contamination can occur
PCR – enzymatic method for repeat copying of specific DNA sequences, amplifies minute quantities of biologic
material (genetic Xeroxing)
Advantages
Disadvantages
-
Excellent sensitivity
-
IDs microbes that cannot be cultured
-
Recent use of 16s ribosome (much shorter t
½
than
DNA) is able to overcome difficulties detecting
viable organisms
-
IDs nonviable microbes (DNA can persist for up to
a year after death)
-
Cost/availability
-
Contamination can occur
-
Technique sensitive
Microscopy
Dark field – illuminates organism against dark background
Bright field – specimens visualized by transillumination
Phase contrast – parallel beams of light pass through objects of different density – phase shifts in beams enable differing
contrast of image
Flourescnece – microorganism stained with fluorescent dye and visualized against dark background
Electron – beams of electrons directed through specimen onto a screen
-
Obligate Anaerobes
o
Cocci – veillonella
o
Rods
Capnocytophaga
Eikenella
Bacteroides
Saccharolytic
Modified saccharolytic (prevotella)
Assaccharolytic (porpyromonas)
o
Spindle – Fusobacterium
o
Spirochetes – Treponema
Endodontics
Course Review
Enoch Ng, DDS 2014
Infection
-
Intrarradicular infections – inside root canal system
o
Primary – initial invasion into root canal system
Polymicrobial – gram +
ve
and –
ve
, >3 specimens
Once microbes invade necrotic pulp, multiply and infect root canal system and dentinal tubules
Coronal region – rapidly growing facultative anaerobes
Apical region – obligate anaerobes
Bacteroides and gram +
ve
anaerobic rods in apical region
o
Secondary – invasion during course of treatment/intervention
o
Persistent – organism survives treatment (clinically indistinguishable from secondary)
1-2 bacterial species, mostly gram +
ve
facultative anaerobes
Primary cause of non-healing endo lesion (inaccessible to debridement, resistant to irrigant)
Both dentin layer bordering pulp (81%) and cementum (62%)
Intracanal bacteria/biofilms primary cause of persistent endo infections
E. faecalis isolated in 38% of endo treated teeth – binds to human collagen and invades
dentinal tubules via ACE binding protein
-
Extrarradicular infections – invasion into apical tissues beyond root canal system
o
Can result from
Extension of intrarradicular infection
Persistence of bacteria in apical periodontitis lesion
Apical extrusion of bacterial infected debris during instrumentation
Independently from intrarradicular infection (Actinomyces)
o
Obligate anaerobes have also been isolated from apical cementum
Biofilms implicated in some instances
o
May lead to formation of apical abscess – accumulation of dead neutrophils, bacterial byproducts,
bacteria, proteins, fluids
Drainage may form a sinus tract
Symptoms
-
Prevotella – pain, sinus tract formation, foul odor
-
Prevotella, peptostrep, eubacterium – pain, swelling, wet canals (hemmorhagic/purulent exudates)
-
Peptococcus, peptostrep, eubacterium, porphyromonas – percussion pain
Irrigants and Medicants
-
NaOCl – hypochlorous acid when contacting organic debris
o
Oxidizes sulfhydryl groups of bacterial enzymes – disrupts metabolism
15min to remove bacteria and biofilms
o
Inhibits DNA replication, disrupts structural proteins
o
Alkaline pH
-
CaOH – creates hydroxyl ions/free radicals = diffuse through dentinal tubules and destroy bacterial membrane
o
Physical barrier – limit proliferation of residual bacteria, prevent reinfection
o
Alkaline pH
o
Breaks down LPS, reacts with bacterial DNA and disrupts replication and metabolism via mutations
-
An infected canal must have the infected dentin removed (cleaning the dentin walls) via instrumentation
Endodontics
Course Review
Enoch Ng, DDS 2014
Inflammation
-
Acute inflammation
o
Vascular/exudative response
o
Leukocyte migration
-
Chronic inflammation
o
Long term irritation
o
Primarily cellular response (macrophages, B and T lymphocytes, plasma cells)
o
Proliferative – fibroblasts, collagen production, neovascularization
o
Increased osteoblastic/osteoclastic activity
-
Pulpal response to caries
o
Chronic
acute
o
Primary immune cells in initial response (lymphocytes and plasma cells)
o
Carious exposure increases inflammation, increased PMNs and macrophages
Distance between pulp/pathogen important – inflammation becomes great <0.5mm from pulp
o
Diffusion of bacterial toxins through tubules induces inflammation before pulpal exposure
With absence of filtration pressure, endotoxin can diffuse though 0.5mm dentin in 15min-4h
o
Exposed pulp with bacterial exposure has severe inflammatory response
Endotoxin concentration very high in necrotic symptomatic teeth and apical lesions
Endotoxin can progress past root canal into apical area – endotoxin found in 75% of
apical lesions associated with necrotic pulp
Apical advancement continues until entire canal is infected and tooth is overwhelmed
Vital tissues can still be present even in necrotic pulp
-
Pulpal inflammation – thermal, spontaneous, and referred pain
-
Apical inflammation – biting, percussion, and palpation pain
Technique
-
Eliminate both infection and inflammation, since infection from caries and endo infections causes inflammation
-
NEED rubber dam (standard of care)
-
Contact time and appropriate delivery of NaOCl, intracanal medicament CaOH
-
Adequate cleaning/shaping, temporary filling, final restoration
-
Aseptic technique needed to prevent introduction into cleaned canal system
-
Soak GP in NaOCl for 1min before obturation to sterilize them
Antibiotic resistance
-
Adherence to prescription guidelines is low
o
10%-42% for pediatric patients in common dental scenarios
o
14%-17% compliance during weekends
-
Indications for antibiotics
o
Fever >100
o
F
o
Malaise, lymphadenopathy, trismus, increased swelling, cellulitis, osteomyelitis, persistent infection
-
34% of prevotella strains from dentoalveolar infections resistant to amoxicillin
Endodontics
Course Review
Enoch Ng, DDS 2014
Rotary Instruments
-
Ideal preparation – continuously tapered funnel maintaining canal anatomy and apical constriction
Shaping Goals
-
Biologic – reduce number of microbes, remove canal contents
-
Mechanical – increase space for irrigants/medicaments, facilitate root canal filling
-
Long term success – prevent vertical fractures, avoid procedural errors
Terminology
-
Glide Path – smooth preparation from chamber orifice to root canals terminal constriction
o
After straight line access and working length are determined, hand files create a glide path with
minimum size of a 20 hand file
-
Master Apical File – largest file used to working length, at least 3 sizes larger than first file to bind
o
Large enough for cleaning of apical portion of canal
o
Maintains original canal anatomy – no strips, zips, perfs, or elbows
o
Apical preparation retains obturation material
Diameter 1mm from Apex:
Small canals – 200-400microns, file size 20-40
Large canals – 400-700microns, file size 40-70
-
Step Back technique – series of progressively larger files that fit successively farther from termination of canal
o
Gives tapered preparation in apical to coronal direction
-
Crown down technique – instruments used from larger to smaller
First instruments do coronal flaring and mid root shaping
Smaller instruments progressively taken to working length
o
Decreases bio-burden carried into canal space, gives continuous coronal flare
o
Decreased contact area of the file – decreased tortional force on NiTi file
o
Enhances tactile awareness, minimizes changes to working length
o
Rotary motion pulls debris out of the canal, instead of pushing it into canal and out apex (extrusion)
Properties and Design
-
NiTi properties – austentic phase, transformation phase, martensitic phase
Transformation phase is where there is relatively little stress change with increased strain
This is the phase where NiTi can return to austentic phase (original shape)
Stainless steel (K-files) – much greater stress increase with relatively little strain (2.8%)
o
Loading plateau – additional stress does not proportionally increase strain
o
Shape memory – deformed files return to original shape because of crystalline form
NiTi files WILL break
-
Land area – flat area between the cutting edges
o
Keeps file centered in canals, adds bulk to resist file fracture
o
Separates “flute” areas
-
Positive (obtuse) angle – less aggressive cutting
-
Negative (acute) angle – more aggressive cutting
Endodontics
Course Review
Enoch Ng, DDS 2014
File Types
K3 files
Properties
Band coding
Design features
-
3 radial lands
-
Positive rake angle, non-cutting tip
-
Lengths 21mm, 25mm, 30mm
Properties
-
Passive, reaming dentin removal
-
Low tendency for canal transportation
-
Leaves a thick smear layer
-
300-350 RPM recommended
Top band – taper
-
0.4 – green
-
0.6 – orange
-
0.8 – blue
-
1.0 – pink
Bottom Band – ISO tip size
-
20 – yellow
-
25 – red
-
30 – blue
-
35 – green
-
40 – black
-
45 – white
Rotary files
Protaper files
Profile
Profile
Design Features
-
3 radial lands
-
Negative rake angle, non-cutting tip
Properties
-
Passive, reaming dentin removal
-
Low tendency for canal transportation
-
Leaves a thick smear layer
-
150-350 RPM recommended
Design features
-
No radial lands
-
Negative rake angle, non-cutting tip
Properties
-
Active cutting dentin removal
-
Higher tendency for canal transportation
-
Thin smear layer, less debris remaining
-
150-350 RPM recommended
Procedural Errors
o
Informed consent before starting, inform patient of referral cases
o
Inform patient of complications immediately
o
Document incident in records
-
Danger zone – apical/middle third of root close to furcation, where dentin/cementum is thin
o
Safety zone – opposite side of danger zone
o
Easy to perforate laterally into danger zone when instrumenting
-
Perforation
-
Zipping – in a curved canal, apex is opened up from file trying to straighten itself out during over
instrumentation by/beyond apex
-
Instrument separation - prevented by
o
Avoid placing excessive stress
o
Use instruments less prone to fracture
o
Follow instrument use protocol
o
Assess canal curvatures radiographically before beginning
o
Open orifice before negotiating canals
o
Create adequate glide path with hand files
o
Use low rotation speeds and torque levels
o
Use crown-down technique
o
Irrigate/lubricate during instrumentation
o
Use pecking/pumping motion (K3 and K4 motion is in-and-out)
o
Practice new systems/techniques on extracted teeth first
Endodontics
Course Review
Enoch Ng, DDS 2014
-
File separation factors in operator control
o
Rotational speed – increased RPM = increased separation rate
o
Operator experience
o
Apical pressure – increased pressure = increased separation rate
o
Instrument taper – increased taper = decreased time to separation
-
Factors out of operator control
o
Canal curvature – radius curvature decrease = decreased time to fracture
-
If unable to bypass/remove file, or if patient has symptoms, can do surgical root canal
o
Open a flap, open the bone, reveal root apex and remove file from bottom of the root
Irrigants/Lubricants
Instruments shape, irrigants clean
Canal shape is variable, some areas cannot be instrumented
Irrigant should be deposited to fill half way up the pulp chamber
o
Use only side vented needle – prevents NaOCl exiting apex
o
Never bind tip in the canal – always keep it in motion
Flush chamber first, then canals
Irrigant only works 1-2mm ahead of the tip
o
Gentle pressure – flushes back out access
o
Measure – use stopper or bend to 2-3mm short of CWL
NaOCl accidents are SERIOUS – edema, hemorrhage, pain, risk of infection
-
Passive ultrasonic irrigation (PUI)
o
File is ultrasonically activated in irrigant filled canal
o
Creates acoustic streaming of irrigant
o
1min of PUI after hand/rotary cleaning/shaping 7x more likely to yield negative culture than hand/rotary
instrumentation by itself
-
EndoVac
o
Negative pressure irrigation
o
Facilitates delivery of irrigant to working length, potential to reduce accidents
o
Significantly better debridement of apical 1mm than need irrigation
-
Lubricant allows for more efficient instrumentation – RC prep, glycol, urea peroxide, EDTA chelating agent
New developments – K3XF, R-phase technology, K3 cross section
-
Vortex file – processing of M-wire gives microstructure containing marsenite
o
Possibly alloy strengthening, increased cyclic flexure fatigue resistance
-
Sybron (twisted file) – R-phase heat treatment optimizes strength and flexibility of NiTi
o
TF cutting flutes created from twisting (not grinding) the file
o
Can withstand significantly more torque
o
Significantly better resistance to cyclic metal fatigue than NiTi’s manufactured from grinding
-
PathFile – rotary file used to establish canal patency (used after #10file to get working length)
o
Apical sizes 13, 16, and 19
o
Significantly less modification of curvature and fewer canal aberrations
-
Self-adjusting file – hollow and thin cylindrical NiTi lattice, adapts to cross-section of root canal
o
Single file used through entire procedure (after a glidepath with a #20 K-file)
o
Preparation with similar cross section but larger dimension than original canal
o
Constant irrigant flow
Endodontics
Course Review
Enoch Ng, DDS 2014
K3 technique
o
After achieving working length, apically enlarge to MAF
-
Initial radiographs – straight on and angled (Mx incisors only require straight on shot)
o
Parallel film optimal for working length estimation
-
Estimated working length on radiograph
-
Access chamber – irrigate with 1-2mL NaOCl
-
ID canal orifices
-
“scout” coronal 2/3 of canal with size #10 file
-
Coronal flare with Gates Gliddens burs
o
Measure chamber floor depth on GG burs
Advance #4 < depth of bur head (~2mm), irrigate 1-2mL NaOCl
Advance #3 3mm past orifice, irrigate 1-2mL NaOCl
Advance #2 6mm past orifice, irrigate 1-2mL NaOCl
o
Hand file to size #20 to create glide path, irrigate 1-2mL between files
-
Estimated working length with #20 file, get CWL
o
If >1mm change, expose new radiograph
o
Once working length is established, measure EVERYTHING placed into canal
-
Use these files to resistance, irrigate and recapitulate with #10 file after each rotary file
o
25/.10 (tip diameter/taper)
o
25/.08
o
35/.06
o
30/.04
o
25/0.6 – if does not reach CWL, repeat sequence
-
Apically enlarge canals with .04 taper (small/curved canals) or .06 taper (large/straight canals) to MAF size
-
Use all files at 300 RPM – special torque controlled motors
-
Final apical file radiograph – made with
HAND FILE
corresponding to MAP
-
Final irrigation with >3mL NaOCl per canal
-
Dry canal with paper points
-
Apical clearing – passive 1/3 turn clockwise rotation with sterile MAF at CWL to remove debris
o
No cutting, just load flutes with debris for removal
Summary
-
Straight line access and glide path necessary for successful rotary instrumentation
-
Irrigation and recapitulation provide many benefits
-
Bacteria cause disease, eliminating them gives patient’s immune system chance to heal
Endodontics
Course Review
Enoch Ng, DDS 2014
Endo Emergencies
-
85% of patients requesting emergency dental pain have pulpal or apical disease – require endo
o
Pain and/or swelling, disrupts daily activities, not relieved by analgesics
o
Acute – few hours/days duration
o
Requires immediate diagnosis and treatment
-
Microbial, mechanical, chemical irritant that damages pulpal/apical tissues causing inflammation or cell death
Caries, deep/defective restorations, trauma
o
Increased tissue pressure in low compliance environment (dental pulp)
o
Chemical mediators of inflammation – vasoactive amines, arachidonic acid, acid metabolites, cytokines
-
Can occur before (pre-treatment), during (interappointment/flare up), or after (post-obturation) NSRCT
Recognizing Emergencies
-
True emergency – needs unscheduled office visit for immediate diagnosis and treatment, cannot be postponed
because of severity
o
Questions to Ask
Disturbs sleep, eating, working, concentrating on daily activities
Face/gums look/feel swollen
Difficulty swallowing
Length of time problem has bothered patient
Intake of pain medication and its effectiveness
o
Clinical Presentations
Asymptomatic or Symptomatic irreversible pulpitis with normal apical tissues
Symptomatic irreversible pulpitis with symptomatic apical periodontitis
Necrotic/previously treated pulp with symptomatic acute periodontitis
Necrotic/previously treated pulp with acute apical abscess (vestibular/facial swelling)
-
Critical urgency – visit can be rescheduled for mutual convenience of patient and dentist
o
Symptomatic irreversible pulpitis (with or without apical diagnosis) that can be managed with analgesics
o
Necrotic/previously treated pulp with mild symptomatic apical periodontitis
o
Necrotic pulp with chronic apical abscess
Treatment Goals
-
Obtain accurate diagnosis
o
Physical condition
Facial swelling, lymphadenopathy, fever, malaise, difficulty breathing
o
Medical/dental history
o
Subjective exam
Spontaneity, intensity, duration of pain
o
Objective exam
Pulpal and apical assessment
-
Goals of treatment
o
Eliminate bacteria, reduce concentration of inflammatory mediators (NSRCT or extraction)
o
Release pressure of exudate/swelling via incision/drainage
-
Rules for treating emergencies
o
Never begin treatment until diagnosis is certain
o
Better to provide no treatment than the wrong treatment
o
When in doubt, refer case for further evaluation
Endodontics
Course Review
Enoch Ng, DDS 2014
Anesthesia
o
Hyperanalgesia of pain receptors in inflamed tissue – increased excitability
o
Patients in pain are often apprehensive – lowers pain threshold
o
Dentists may not allow sufficient time for anesthesia to work
-
Supplemental Anesthesia
o
Premedication analgesics (600mg ibuprofen)
o
Greater volume of anesthetic
o
Bupivacaine (Marcaine)
o
PDL injection
Use new sterile needle (no contamination of PDL space)
Inject at 3 points buccal and 3 points lingual around the tooth (line angles)
Look for blanching of tissue in area of injection
o
Intrapulpal injection
Use new sterile needle (no contamination of pulp)
Backpressure (not anesthetic itself) is responsible for anesthesia
Patient may experience pain on injection, anesthesia duration only lasts 15min
o
Intraosseous injection
X-tip or stabident, high success rate in cases of failed IAN block
Transient (~4min) tachycardia when epi is used
Avoided with use of mepivicaine (without epi)
-
Analgesia
Antibiotics
o
Pen VK or amoxicillin – loading dose 1000mg, 500mg every 6hr over 7 days
If symptoms don’t improve
Add 500mg q 8hrs metronidazole
Augmentin (amoxicillin and clavulanate)
o
Penicillin allergy – clindamycin 600mg loading dose, 300mg q 8hrs over 7 days
-
Antibiotic concerns
o
Colitis from clostridium overgrowth – watery diarrhea, abdominal pain, cramping, low grade fever
o
Patients taking oral contraceptives
-
Post-op instructions
o
Pain and swelling takes time to absolve
o
Need proper nutrition, adequate fluids, compliance
-
Will call every day to check up on patient until symptoms resolve
Endodontics
Course Review
Enoch Ng, DDS 2014
Systematic Approach to Treatment
-
[A]symptomatic irreversible pulpitis with normal apical tissues
Asymptomatic irreversible pulpitis – carious pulp exposure
o
Pulpotomy/partial pulpectomy
Coronal tissue removal to level where hemostatis can occur with moist cotton pellet
Temporize, plan to complete NSRCT within 4 weeks
o
Analgesics for mild pain, do NOT need antibiotics
-
Symptomatic irreversible pulpitis with symptomatic apical periodontitis
o
Total pulpectomy
Instrument canals to proper working length, place Ca(OH)
2
Temporize, plan to complete NSRCT within 4 weeks
o
Analgesics for moderate/severe pain, do NOT need antibiotics
-
Necrotic/previously treated pulp with symptomatic apical periodontitis
o
Total pulpectomy
o
Analgesics for moderate/severe pain, do NOT need antibiotics
-
Necrotic/previously treated pulp with acute apical abscess
o
Total pulpectomy
o
Drain either through tooth or incision though most fluctuant point of swelling
o
Analgesics for moderate/severe pain
o
Antibiotics for systemic involvement, inadequate surgical drainage, diffuse swelling,
persistent/progressive infections, immunocompromised patients
Interappointment Emergencies (Flare-Ups)
Symptoms
-
Pain/swelling which necessitates unscheduled visit
-
Low incidence (1.8-3.2%)
-
Causative factors – pre-op pain/swelling, pre-op
apical diagnosis of SAP or AAA, apical radiolucency
Prevention
-
Long acting local anesthetic
-
Complete cleaning/shaping
-
Analgesics
-
Psychological preparation of patient
-
Verbal instruction
Treatment
-
Check occlusion
-
Reassure patient with prescription for
mild/moderate analgesic
-
For pain with no swelling – reaccess tooth,
reconfirm CWL, complete cleaning and shaping,
remedicate, analgesics
-
For pain with swelling – reaccess tooth, reconfirm
CWL, complete cleaning and shaping, remedicate,
incision and drainage, analgesics, antibiotics if
systemic symptoms present
-
Hospitalization
Follow-up Care
-
Contact patient daily until symptoms resolve
Post-obturation Emergencies
-
Infrequent
-
Pain at mild level from overextension of obturating material associated with highest incidence of discomfort
-
Reassure patient, provide analgesics, double check right treatment was provided
-
If pain persists – surgical RCT, extraction
Indications for Hospitalization
-
Difficulty breathing/swallowing, elevated tongue, bilateral submandibular swelling, soft palate swelling
-
Difficult patient compliance, dehydration, appropriate monitoring, extra-oral surgical drainage
Endodontics
Course Review
Enoch Ng, DDS 2014
Root Resorption
-
Condition associated with physiologic or pathologic process resulting in loss of dentin, cementum, and/or bone
o
Similar to process of bone resorption
o
Involves dentinoclasts and cementoclasts
Resorption Mechanism
-
Clastic cells bind to extracellular proteins containing arginine-glycine-aspartic acid sequence (RGD) of aminoacids
-
RGD peptides bound to calcium salt crystals on mineralized surfaces serve as clastic cell binding sites
-
Activated clastic cells produce acidic pH (3.0-4.5) – increases hydroxyapatite solubility
-
Covering of cementum and predentin over dentin essential to resistance of dental root resorption
o
Clastic cells cannot bind to unmineralized matrix
-
Bacteria and inflammation are part of the process
-
Differential diagnosis – important for treatment planning – NSRCT vs surgical repair
Internal Root Resorption
-
Pathologic process initiated within pulp space with loss of dentin and possible invasion of cementum
o
Clastic cells come from dental pulp
-
Outermost odontoblastic layer and predentin layer of canal wall damaged, exposes mineralized dentin layer to
clastic cells
-
Pulpal tissue apical to resorptive lesion must have viable blood supply to sustain clastic cells
Internal inflammatory resorption
-
Often associated with history of trauma
-
Requires vital pulp for progression
-
Low grade chronic pulpal inflammation
-
Asymptomatic unless perforation occurs
-
Can be transient or progressive
-
Displays as pink tooth mummery
Radiographic features
-
Fairly uniform, clearly defined radiolucent
enlargement of canal
-
Canal cannot be seen through resorptive defect
-
Defect stays centered on angled radiograph
Internal replacement resorption
-
From low-grade irritation to pulpal tissue, like
chronic irreversible pulpitis or partial necrosis
-
Pulpal tissue replaced with bone or cementum like
hard tissue
Treatment – Immediate NSRCT
-
Process halted by pulpal extirpation
-
Ultrasonic cleaning with NaOCl
o
For perforations, use normal saline or
chlorhexidine (not NaOCl)
-
Hemorrhage control essential, can be difficult
-
Ca(OH)
2
treatment interappointment
-
Obturation with warm gutta percha technique
Treatment
-
Ultrasonic cleaning with NaOCl
o
For perforations, use normal saline or
chlorhexidine (not NaOCl)
-
Ca(OH)
2
treatment interappointment
-
Obturation with warm gutta percha technique
Endodontics
Course Review
Enoch Ng, DDS 2014
External Root Resorption
-
Pathologic process initiated in periodontium, initially affecting external tooth surfaces
o
Clastic cells from the periodontium
-
Radiographic features
o
Irregular radiolucent enlargement of canal
o
Root canal space can be followed through resorptive defect
o
Defect moves on off angled radiographs
-
External Surface Resorption
o
Physiologic process causing small superficial defects in cementum and underlying dentin, which are
repaired by deposition of new cementum
o
Localized inflammatory response/localized area of resorption/repair
o
Transient (2-3 weeks long)
o
Self-limiting
o
Occurs in >90% of teeth
o
Small, generally not radiographically visible
o
No treatment
-
External Replacement Resorption
Ankylosis – clinical diagnosis of end result of replacement resorption where tooth is no longer
capable of normal physiologic movement from fusion of bone to root surface
Dull sound from percussion
Change in incisal edge as patients grow/develop
o
Pathologic loss of cementum, dentin, PDL, with subsequent replacement of such structures by bone,
causing fusion of bone and tooth – a “mistake” vs a disease process
o
Frequent complication of avulsions and luxation injuries
o
Loss of PDL and cementum layer leads to replacement of tooth structure with bone
o
Diagnosis
Radiographic loss of PDL, bone replacing tooth structure
Lack of physiologic mobility
Metallic sound upon percussion
o
Treatment
No predictable treatment
Slow progression
Goal is prevention
Endodontics
Course Review
Enoch Ng, DDS 2014
-
External Inflammatory Resorption
o
Pathologic loss of cementum, dentin, and bone causing defect in root and adjacent bone tissues
Caused from infection, characterized by radiolucent areas along the root
May or may not invade dental pulp space!
o
Subtypes
Cervical
o
Invasive cervical
Heathersaiy Classification
Class I – small invasive resorptive lesion near cervical area,
shallow penetration into the dentin
o
100% success rate
Class II – well defined invasive resorptive lesion penetrated
close to coronal pulp, little/no extension into radicular dentin
o
100% success rate, may require NSRCT
Class III – deeper invasion of dentin by resorbing tissues, coronal
dentin and extending to coronal 1/3 of root
o
Initial retention 92%, long term retention 77%
o
95% treated with NSRCT
Class IV – large invasive resorptive process extended beyond
coronal 1/3 of root
o
Long term success 12%
o
Unable to totally remove resorptive lesion in most cases
o
Extracanal invasive
o
Subepithelial external inflammatory (from sulcular infections)
-
Predisposing factors
o
Trauma
o
Intracoronal bleaching
o
Periodontal therapy
o
Bruxisum, intracoronal restorations,
development defect, systemic disease
o
Idiopathic
-
Contributing factors
o
Mechanical damage to cementum
o
Stimulation from bacteria
-
Diagnosis
o
Begins from pinpoint opening in cementum
o
Occurs just below epithelial attachment
o
Invades dentin – leaves cementum and pulp
intact
o
Pulp usually vital
o
Root canal system radiographically intact
o
Radiographically may resemble caries
o
“pink” tooth
Treatment
Ca(OH)
2
MTA
o
Depends on extent and location
Supraosseous
NSRCT with Ca(OH)
2
interappointment medication
Flap and restore
Extrude and restore
Intraosseous
NSRCT with Ca(OH)
2
interappointment medication
Flap and repair/restore
Extraction/replantation
Endodontics
Course Review
Enoch Ng, DDS 2014
Apical
Stimulated by leakage of inflammatory mediators from root canal system
Possible history of trauma
More often with pulpal diagnosis of necrotic pulp
Treat with NSRCT
o
Create apical stop in sound dentin, or place an apical barrier
-
Pressure Resorption
o
Etiology
Orthodontics
Impacted teeth
Tumors/cysts
o
Factor
Pulp usually not involved
Resorption is arrested when cause is removed
o
Treatment
Remove cause
Summary
-
Covering of dentin by cementum and pre-dentin essential to resistance of the dental root essential for
resistance of the dental root to resorption
o
Damage to these tissues can start process
o
Bacteria and inflammation are part of the process
-
Treatments
o
Internal Resorption
NSRCT
Perforations
Long term Ca(OH)
2
– apexification techniques
MTA (proroot) repair
o
External resorption
Surface – none required
Replacement – observe, no treatment found successful
Endodontics
Course Review
Enoch Ng, DDS 2014
Pediatric Endodontics
Indications
-
The successful treatment of the pulpally involved tooth is to retain that tooth in a healthy condition so it may
fulfill its role as a useful component of the primary and young permanent dentition
-
Sequelae (pathosis) of premature loss
o
Loss of arch length
o
Insufficient space for erupting permanent teeth
o
Ectopic eruption, premolar impaction
o
Mesial tipping of molars adjacent to lost primary molars
o
Extrusion of opposing permanent teeth
o
Midline shift, possible crossbite occlusion
o
Development of abnormal tongue positions
Considerations of Primary Dentition
-
Developmental Considerations
o
Root length completed 1-4 years after eruption
o
Permanent tooth bud apical lingual to primary anterior tooth
-
Anatomic Considerations
o
Relatively larger pulp chambers
o
Mesial pulp horns extend closer to outer surface
o
Accessory canals in pulp chamber floor lead directly into furcation
o
Ribbon-like canals
o
Roots are narrower mesial-distally
o
Root more divergent than in permanent teeth
-
Primary Pulp Tissue
o
Responds differently that permanent teeth to trauma, infection, irritation, medication
o
Loss innervation density – diagnosis is more difficult
o
Larger apical foramina – greater inflammatory response
-
Open Apex
o
Developing root of immature tooth, root growth retarded in presence of disease
o
Closure normally 3years after eruption, resorption of mature apex may be from ortho, healing after
trauma, periradicular inflammation
Pulpal Diagnosis in Kids
-
Visual and tactile examination of carious dentin and associated periodontium
-
Radiographics of
o
Periradicular and furcation areas
o
Pulp canals
o
Periodontal space
o
Developing permanent tooth
-
History spontaneous pain
-
Pain percussion, mastication
-
Mobile
-
Palpation surrounding soft tissues
-
Size, appearance, and amount of hemorrhage associated with pulp exposure
Endodontics
Course Review
Enoch Ng, DDS 2014
Pulpal Therapy in primary and young permanent teeth
-
Indirect pulp therapy
o
Usually not in primary teeth, no clinical/radiographic signs of pathology
o
Arrest carious process, provide conducive conditions to reactionary dentin formation
o
Promote remineralization of altered dentin left behind, promote pulpal healing
-
Direct pulp cap
o
Seal exposure with biocompatible material prior to coronal filling, exposure >24h negates success
o
Zone of tissue necrosis from CaOH differentiation takes place, irregular osteo/tubular/tertiary dentin
o
Indications
Pinpoint mechanical exposure with no prior symptoms
o
Contraindications
Carious pulp exposure is NEVER pulp capped – do pulpotomy
o
Technique
Local anesthetic, rubber dam
Removal of all caries – no further pulpal removal
Disinfection with NaOCl <10-15min, hemostasis with moist cotton pellet
1mm MTA sealer, moist cotton pellet and cavit seal
Patient checked after 12-48h for MTA setting, bonding restoration placed
-
Pulpotomy
o
Surgical removal of entire coronal pulp presumed to be partially or totally inflamed, possibly infected.
Leave vital radicular pulp in canals – promote healing and retention of vital radicular pulp.
o
Success rate depends on operator ability to differentiate inflamed coronal and radicular pulp
o
Indications
Carious pulp exposure
Want to keep tooth instead of using space maintainer
Inflammation confined to coronal
Tooth restorable
At least 2/3 remaining root length
o
Contraindications
History of spontaneous pain
Uncontrolled hemorrhage after coronal pulp amputation – indicate radicular inflammation
Sinus tract of pus in pulp chamber – indicates necrosis
o
Technique
Local anesthesia, rubber dam
Caries removal, bleeding from exposure shows vital pulp tissue
Remove entire chamber roof, lots of water
Removal all coronal pulp fibers with slow speed or spoon excavator
Thorough rinse and dry with cotton pellets
Control hemorrhage with cotton pellets against pulp stumps – clotting in 3 min usually
If remaining bleeding, check all coronal fibers removed, may indicate radicular inflammation
Seal, for young permanent dentition NSRCT done after root development
o
Islets of tertiary dentin formed after 4 months – can obliterate canal
Endodontics
Course Review
Enoch Ng, DDS 2014
Ferric Sulfate
o
15.5% added to orifices 10-15s, flush chamber with distilled water
o
Dry with sterile cotton pellets, seal wounds with ZnO-Eugenol
o
Restoration, SSC (posterior) or composite (anterior), judicious monitoring/recall
MTA
Improved pulp protection, biocompatible
Small amount of blood/moisture is fine – moisture needed for curing
o
Shallow pulpotomy, place MTA, allow 6-24h to cure, place restoration
o
Disadvantages – 2 appointments, expensive
Formal Cresal - BAD
o
19-35% formaldehyde – absorbed systemically within minutes
o
Severe inflammatory agent, metabolized in liver, RBC, brain, kidney, muscle
o
Antigenically alters tissue
Gluteraldehyde, electrosurgery, laser, Ca(OH)
2
– problems with internal resorption
-
Primary Pulpectomy
o
Difficult cleaning and shaping of bizarre and torturous canal anatomy in primary molars
Especially when molars have open apex due to resorption
o
Abscess can negatively affect formation of developing tooth bud
o
Consider restorability, extraction with space maintainer
o
Maintain tooth free of infection, clean canals, promote physiologic root resorption, hold space
o
Indications
IRP or pulpal necrosis
Want to keep tooth instead of using space maintainer
o
Contraindications
Severe root resorption
Surrounding bone loss from infection
Non-restorable tooth
o
Technique
Local anesthetic, rubber dam
Access, instrument 2-3mm from radiographic apex (no gates glidden), beware of developing bud
Dry with paper points, fill canals with hard setting ZOE or other paste
Restore, cover with SSC
-
Apexogenesis
o
Vital pulp therapy encouraging continued physiologic development and formation of root end
Deep pulpotomy, success dependent on extent of pulpal damage and restorability
Large caries/traumatic exposure may require pulpotomy – apexogenesis done if pulptomy fails
Usually use Ca(OH)
2
– MTA can be used, but harder to re-enter
After root formation, clinician can reenter and RCT may be completed
o
Pulp capping and pulpotomies in immature teeth essentially apexogenesis
