TEETH LARGER THAN THEY SHOULD BE
SINGLE ENAMEL ORGAN ATTEMPTS TO MAKE TWO TEETH
TWO CROWNS – ONE ROOT
JOINING OF TWO DEVELOPING TOOTH GERMS
MAY INVOLVE ENTIRE TOOTH OR JUST CEMENTUM AND DENTIN
ROOT CANALS MAY BE SEPARATE OR SHARED
MAY BE IMPOSSIBLE TO SEPARATE FUSION OF A NORMAL AND SUPERNUMERY TOOTH FROM GEMENATION
FORM OF FUSION IN WHICH ADJACENT TEETH ARE JOINED BY CEMENTUM
MOST COMMONLY SEEN BETWEEN MAXILLARY 2ND AND 3RD MOLARS
EXTRAORDINARY CURVING OR ANGULATGION OF TOOTH ROOTS
CAUSE RELATED TO TRAUMA DURING TOOTH DEVELOPMENT
COMMON DEVELOPMENTAL CONDITION AFFECTING PREDOMINANTLY PREMOLAR TEETH
ALMOST EXCLUSIVELY OF THE MONGOLOID RACE
ANOMALOUS TUBERCLE OR CUSP LOCATED IN THE CENTER OF THE OCCLUSAL SURFACE
TEETH THAT HAVE ELONGATED CROWNS OR APICALLY DISPLACED FURCATIONS
PULP CHAMBERS HAVE INCREASED APICAL-OCCLUSAL HEIGHT
ASSOCIATED WITH SYNDROMES SUCH AS DOWN AND KLINEFELTER’S
HIGH PREVELANCE IN ESKIMOS AND 11% IN MIDDLE EAST
DROPLETS OF ECTOPIC ENAMEL
COMMONLY SEEN IN THE BIFURCATION OR TRIFURCATION AREA OF TEETH
MAX MOLARS MOR COMMON
ABSENCE OF TEETH
MOST COMMON ARE 3RD MOLARS THEN MAX LAT INCISSORS AND SECOND PREMOLARS
COMPLETE ANODONTIA ASSOCIATED WITH ECTODERMAL DYSPLASIA- X-LINKED RECESSIVE DISORDER
ASSOCIATED WITH GARDNERS SYNDROME AND CLEIDOCRANIAL DYSPLASIA
THE ANTERIOR MIDLINE OF THE MAXILLA IS THE MOST COMMON SITE FOLLOWED BY MAXILLARY MOLAR AREA
HERIDITARY DISORDER OF ENAMEL FORMATION IN BOTH DENTITIONS
HYPOPLASTIC – INSUFFICIENT AMOUNT OF ENAMEL
HYPOCALCIFIED – QUANTITY OF ENAMEL IS NORMAL BUT SOFT AND FRIABLE
COLOR RANGE FROM WHITE OPAQUE TO YELLOW TO BROWN
RADIOGRAPHICALLY DENTIN THIN ROOTS NORMAL
DEFECTS OF DENTIN
DENTINOGENESIS IMPERFECTA (HEREDITARY) OPALESCENT DENTIN
TYPE 1 – OCCURS IN PATIENTS WITH OSTEOGENESIS IMPERFECTA
TYPE 2 – PATIENTS HAVE ONLY DENTAL ABNORMALITIES NO BONE DISEASE
TYPE 3 – OR BRANDYWINE TYPE SIMILAR TO TYPE 2 BUT INCLUDE FEATURES SUCH AS MULTIPLE PULP EXPOSURES AND PERIAPICAL RADIOLUCIENCIES
CLINICALLY ALL THREE TYPES SHARE NUMEROUS FEATURES
TEETH EXHIBIT AN UNUSUAL TRANSLUCENT, OPALESCENT APPEARANCE
COLOR RANGES FROM YELLOW – BROWN TO GRAY
ENAMEL NORMAL BUT FRACTURES EASILY
ABNORMAL MORPHOLOGY TEETH TULIP OR BELL SHAPED DUE TO CONSTRICTION OF CEJ
ROOTS ARE SHORT AND BLUNTED
TYPES 1 AND 2 PULP SPACE OPACIFIED
TYPE 3 PULP CHAMBERS AND ROOT CANALS EXTREEMLY LARGE
AUTOSOMAL DOMINANT TRAIT
TYPE 1 RADICULAR
TEETH SHOW GREATER RESISTANCE TO CARIES
ROOTS EXTREMELY SHORT
PULPS LARGE (THISLE TUBE)
ROOTS EXTREMELY SHORT
Radiographic Exam Overview
Can a PARL be seen with irreversible pulpitis?
Yes – Yamasaki – Rat study demonstrating PARL prior to pulp necrosis
Jordon, Suzuki & Skinner – PARL with IP; 11/24 healed with IDPC
How much bone loss before a PARL is noted radiographically?
Bender – Avg 7% MBL & at least 12.5% CBL; lesion must penetrate endosteum
Lee & Messer – Lesions in cancellous bone detected if lamina dura is affected
What radiographic features are important when evaluating PA pathology?
Kaffe & Gratt – continuity & shape of lamina dura; width & shape of PDL
How many films should be taken for diagnosis?
Byrnholf – 73% accurate with 1 film; 87% accuracy with 3 films
How accurate is our radiographic assessment?
Goldman, Pearson & Darzenta - 6 examiners agreed 47%; 6-8mo later they agreed approx. 80% with their first interpretation
What is the most accurate technique?
Forsberg – paralleling is more accurate in length determination vs. bisecting angle
What type of conventional film (speed) is the most diagnostic?
Eleazer & Farman – NSD in WL measurements or image preference
Compare conventional radiography to digital:
Evaluating for PARL
Mistak & Loushine – NSD between digital, transmitted digital & conventional radiography for PARL identification
Folk – NSD between shick (cmos) & trophy RVG ui (ccd)
Nair – conv. film displayed the highest % of PARL detection (vs. ccd & storage phos.)
Comparing WL measurements
Lamus & Katz – NSD between shick & conv.
Goodell & McClanahan – Kodak > schick or conv. for size 10 & 15 files
Lozano – Conv. was more precise with any size file (digital ok with size 15 file)
How much radiation reduction is there between digital and conventional radiography?
Soh – Used only 22% of radiation dose compared to conv. film
Ludlow, Platin & Mol – Insight (f speed) required 44% of exposure of Ultra (D speed)
Is 3-D imaging better than conventional radiography?
Low – improved detection of PA lesions and missed canals with Cone-beam Tomography
Subjective / Objective Overview
Can pts. determine which tooth hurts?
Friend & Glenwright - No, only 37% accurate; usually tooth to either side; 3.4% referral to opposite jaw; 1.5% referral across midline
Discuss cold testing?
Trowbridge & Franks – response sooner than temp change @ PDJ – supports Branstom
Walton / Miller – response quicker with endo ice; use with FCC
Jones – use large cotton pellet
Who discussed heat testing?
Cooley – hot water test
Does temp testing harm the tooth?
Peters – CO2 does not harm the enamel
Rickoff & Trowbridge – heated GP or CO2 showed no pulpal injury
Nahri – stimulates A-beta and A-delta fibers; not C-fibers
Abdel Wahab & Kennedy – slow increase in current – 2uA/sec
Mumford – no relationship with value and pulp pathology
Where do you place the probe tip?
Bender – incisal-edge of incisors
Jacobson – occlusal two-thirds of the buccal surfaces of max incisors and premolars
Is EPT safe on pts. with pacemakers?
Yes – Baumgartner
Can you tell the histologic dx from clinical test?
Seltzer & Bender – No, only correlation exists, but not extent of pathology
How reliable are our pulp tests?
Petterson & Soderstrom –
probability the neg.=necrosis: cold – 89%; EPT – 88%; hot – 48%
probability the pos.=vital: cold – 90%; EPT – 84%; hot – 83%
Fulling & Andreasen – cold test are more reliable in kids
Do any other pulp tests have potential?
Ingolfsson & Tronstad – Laser dolpler flowmetry is more accurate than EPT
Wilcox & Johnson – pulse oximetry
What causes pain while flying / diving?
Ferjentsik – Barodontalgia - Navy study found 86% with faulty restorations
American Board of Endodontics Pulpal & Periapical Diagnostic Terminology:
Normal pulp – A clinical diagnostic category in which the pulp is symptom free and normally responsive to vitality testing.
Reversible pulpitis – A clinical diagnosis based upon subjective and objective findings indicating that the inflammation should resolve and the pulp return to normal.
Irreversible pulpitis – A clinical diagnosis based on subjective and objective findings indicating that the vital inflamed pulp is incapable of healing.
Symptomatic – Lingering thermal pain, spontaneous pain, referred pain
Asymptomatic – No clinical symptoms but inflammation produced by caries,
caries excavation, trauma, etc.
Pulp necrosis – A clinical diagnostic category indicating death of the dental pulp. The pulp is non-responsive to vitality testing.
Previously Treated – A clinical diagnostic category indicating that the tooth has been endodontically treated and the canals are obturated with various filling materials, other that intracanal medicaments.
Previously Initiated Therapy – A clinical diagnostic category indicating that the tooth has been previously treated by partial endodontic therapy (e.g. pulpotomy, pulpectomy).
Normal apical tissues – Teeth with normal periradicular tissues that will not be abnormally sensitive to percussion or palpation testing. The lamina dura surrounding the root is intact and the periodontal ligament space is uniform.
Symptomatic apical periodontitis – Inflammation, usually of the apical periodontium, producing clinical symptoms including painful response to biting and percussion. It may or may not be associated with an apical radiolucent area.
Asymptomatic apical periodontitis – Inflammation and destruction of apical periodontium that is of pulpal origin, appears as an apical radiolucent area and does not produce clinical symptoms.
Acute apical abscess – An inflammatory reaction to pulpal infection and necrosis characterized by rapid onset, spontaneous pain, tenderness of the tooth to pressure, pus formation and swelling of associated tissues.
Chronic apical abscess – An inflammatory reaction to pulpal infection and necrosis characterized by gradual onset, little or no discomfort and the intermittent discharge of pus through an associated sinus tract.
NS RCT Overview
Who was instrumental in developing the apex locator / Root ZX?
Suzuki – electrical resistance between periodontium & oral mucous membrane was 6500 ohms in dogs
Sunada – found same results in human (basis for resistance type EALs)
Kobayashi – developed the Root ZX base on a ratio of impedance at 8 and .4 kHz frequencies
How accurate is the Root ZX?
Shabahang – 96.2% +/- .5mm of the apical foramen
Ounsi – 84% accurate – use apical foramen (major diameter) as measurement
Does the pulp status affect EAL readings?
Dunlap – NSD between vital and necrotic pulps
Does the irrigant solution affect the reading?
Jenkins – No; NSD in function with 7 irrigants tested
Does apical resorption or an open apex affect the reading?
Goldberg – accurate with resorption
Katz – preferable method to determine WL in primary dentition
Are EALs safe for use in pts with pacemakers?
Garofalo & Dorn – In vitro Root ZX safe – Bingo caused interference
Baumgartner – In vivo study found EALs and EPTs safe in 27 pts
Why is the ideal working length .5 – 1mm short of the apex
Burch and Hulen – avg. .59mm from occlusal aspect of maj diameter to apex
Kuttler - .525mm (18-25yr olds) - .659mm (.55yr olds) from major to minor diameter
Discuss historical preparation techniques?
Clem, Mullaney – Step back
Torabinejad – Passive Step back
Marshall – Crown Down Pressureless
Abou Ross – Anticurvature Filing
Roane – Balanced Force
Do you preflare the canal and why?
Stabholz – better tactile sense of the apical constriction
Ibarrola – preflaring allowed more consistent EAL readings (allowed access to apical foramen)
Roland - .04 taper NiTi files were far less likely to separate in preflared canals
Can patency filing cause problems?
Goldberg – cause apical transportation (61% #25, 25% #10) – use small files
Why do you create a guide path?
Peters – No Protaper instrument fractured is guide path was created
What are the advantages of the balanced force technique?
Wu & Wesselink – produced cleaner apical portion of canals vs other hand techn.
McKendry – extruded less debris
Sepic – less apical canal alteration in curved canals vs step back techn.
Why would you choose to use NiTi rotary files over SS hand files?
Baumgartner – NiTi rotaries were faster and stayed more centered
What are the properties of NiTi files?
Haikel – 55% Nickel / 45% Titanium; 2 phases: Austentite & Martensite – cycling between the two phases allows for superelasticity and shape memory; radius of curvature is most important factor for cyclic fatigue, causing failure
Do NiTi files remove more bacteria?
Trope – Not any more effected than SS hand files
Peters – all type of NiTi rotaries left 35% or more of canal surface area unchanged
At what speed should NiTi rotaries be run at?
Gabel & Hoen – Profiles at 333 rpm separated 4x more often as files at 167 rpm
Gambarini – recommended electric low torque or right torque motors
How many times can NiTi files be used
Yared – Up to 10 canals (2-3 cases)
Does sterilization affect NiTi files
Hicks – 10 cycles through heat sterilization did not increase chance of fracture
How large should the apical preparation be for irrigation?
Brilliant – size 30
What makes sodium hypochlorite antibacterial?
Hurst – pH 11; hypochlorus acid is the active antibacterial property of sodium hypochlorite; disrupts oxidative phosphorylation and other membrane activites
Why use full strength sodium hypochlorite?
Hand, Smith & Harrison – dilution of 5.25% significantly decreases the ability to dissolve necrotic tissue
Siqueira – Increased concentration (4%) most effective against gram – anaerobes and facultative anaerobes
Baumgartner – 5.25% is safe for clinical use and does not increase postop pain
When should chlorhexidine be considered as an irrigant?
Jeansonne – 2% chlorhexidine & 5.25% NaOCl showed NSD in antibacterial activity; CHX does not dissolve tissue; Consider with NaOCl allergies, perfs and open apicies
Haapasalo – CHX activity is reduced by dentine
What about MTAD?
Torabinejad – Doxycycline, citric acid & Tween-80; use with NaOCl and recommended for smear layer removal – did not cause dentinal erosion seen with EDTA; kills E. faecalis more effectively than NaOCl
Who discussed smear layer removal?
McComb & Smith – 1st to describe; used NaOCl & REDTA
Sen – made up of organic & inorganic debris (pulp, bacteria and byproducts)
Baumgartner – 2 layers: 1-2 microns thin layer on canal wall; up to 40 microns in tubules
Should the smear layer be removed?
Torabinejad – Yes - in infected cases it allows more thorough disinfection of canal & tubules; allows better adaptation of obturation material
Jeansonne – less coronal leakage with smear layer removal (AH 26)
Walton & Drake – No – blocks bacterial entry into tubules
How do you remove the smear layer?
Calt - > 1min EDTA caused excessive peritubular and intertubular erosin
Crumpton & McClanahan – 1mL 17 % EDTA for 1 min, followed by 3mL NaOCl
What is EDTA & how does it work?
Ethylendiamine tetraacetic acid – Chelating agent – collects Ca ions in dentin making it softer
Schilder – self limiting after 7hrs
How do ultrasonics work?
Ahmad, Pitt Ford & Crum – acoustic streaming & not cavitation
Do ultrasonic remove more bacteria?
Sjogren & Sundqvist – ultrasonics were better than hand instrumentation
Are ultrasonics effective in cleaning canals?
Jensen & Hutter – 3min passive sonic or ultrasonic following hand instrumentation produced cleaner canals
Discuss Calcium hydroxide and how it works?
Hermann – introduced
Siqueira – · Hydroxyl ions create free radicals destroying components of bacteria cell membranes.
· Free radicals (hydroxyl ions) react with bacterial DNA inhibiting DNA replication and cell activity.
· Increased pH (12.5) alters enzyme activity disrupting cellular metabolism and structural proteins.
· Ca(OH)2 effective when in direct contact with bacteria which may not always be possible such as bacteria located in dentinal tubules or in the center of bacterial colonies. pH in tubules is increased, but only up to 8-11 (Tronstad).
· Certain bacteria such as enterococci tolerate high pH levels of 9-11.
· Vehicle used to deliver Ca(OH)2 must not alter the pH significantly.
Safavi & Nichols – inactivates LPS in vitro
How long do you keep Ca(OH)2 in the canal?
Sjogren & Sundqvist – 7 day dressing eliminated bacteria that survived instrumentation
Nerwich, Figdor & Messer – 2-3wks before increase in outer root dentin pH (9.3)
Andreasen – use < 1mo
How do you place Ca(OH)2 in the canal?
Sigurdsson & Madison – lentulo>injection>K-file
How do you remove Ca(OH)2 from the canal?
Kenee – use rotary or ultrasonics over irrigation alone (none completely removed)
Discuss the hollow tube theory?
Richert & Dixon – introduced; canal must filled to the end to prevent outward diffusion of circulatory elements which cause inflammation
Torneck – sterile empty polyethylene tubes healed in rat ct – disputes HTT
Goldman – no evidence of inflammation at the open ends of Teflon rods implanted in guinea pigs – disputes HTT
Wenger – Polyethylene tubes sealed 1mm short with GP/Grossman’s cement elicited little or no inflammation in rat bone – disputes HTT
What is gutta percha made of and what are its properties?
Friedman – 65% Zinc oxide; 20% GP; 10 metal sulfates (radiopacity); 5% waxes and resins
Schilder – GP exists in beta-semicrystalline state; undergoes change to alpha phase upon heating (42-29 C); compactable not compressable
Is latex allergy a concern for gutta percha? Is it biocompatible?
Costa & Johnson – no cross reactivity but slight concern with gutta balata additive
Nair – large pieces were encapsulated and free of inflammation; fine particles evoked inflammatory reponse (macrophages and multi-nucleated giant cells)
How do you sterilize gutta percha points?
Senia – 1min immersion in 5.25% sodium hypochlorite
How do you place sealer?
Wilcox – NSD found between file, lentulo, ultrasonics or coated MC
Does extrude material cause problems?
Augsburger & Peters – did not prevent healing; removed over 6 yr period
Baumgartner - extruded GP or sealer was associated with postop pain
What type of spreader should be used for lateral compaction? How far should it penetrate?
Joyce – NiTi induce less stress and decrease risk of VRF
Walton – less leakage with deep spreader penetration (within 1-2mm)
Discuss the custom cone technique?
Keane – 1 sec dip gave best adaptation and less leakage
Compare lateral compaction and warm vertical technique?
Baumgartner – NSD in bacterial leakage (continuous wave vs cold lat)
Reader – NSD in fill quality; more lateral canals obturated with warm techniques
Can warm techniques damage the periodontium?
Eriksson & Albrektsson - > 10 deg C is threshold level for bony necrosis
Sweatman & Baumgartner – System B, obtura and ultrasonic delivery of GP < 10 deg change at external root surface
Does the Thermafil system work well?
Walton – Thermafil leaked most possibly due to stripping of GP off carrier
Is Resilon a better obturation material?
Trope – teeth were more resistant to fx
Pashley – NSD in leakage compared to GP/AH plus
Is there a problem with Sargenti Paste?