important lit

Cheung, Lai, Ng 2005

32.5% of abutments need Endo, 15.6% of PFM crowns developed pulpal necrosis

, 14 year followup

Krasner and rankow 2004

Pulp chamber laws

Bystrom 1985

E. Facelis has a proton pump making it resistant to CaOH

Kuttler 1955

Major foramen doesn't coincide with vertical apex, in younger teeth on average .48mm difference, in older teeth .6mm

Stein, Corcoran 1990

Major foramen doesn't coincide with vertical apex (only 21%). Separate with time due to age. Minor to major .724mm. CDJ .189mm constant

Sam Kahler 2018

Thin fragile roots not long term CaOh placement responsible for root fracture, "Kahler et al found that the use of long term calcium hydroxide for up to 9 months had no great effect on the fracture susceptibility compared to controls in an in vitro study utlizing lamb teeth"

Ricucci 2018

Extra-radicular infection found in 83% of cases with chronic abscesses

Rosenberg 1998

Occlusal reduction may be effective if reducing post-op pain with vital pulp, percussion positive and pre-op pain

Ricucci 2014

Found histologically speaking diagnosis 97% matched fundings in normal or reversible and 84% matched in SIP

Cameron 1976

CTS additional findings only 25% of cracked teeth needed endo or EXT

Davis 2019

success rates of upwards of 90.6% at 2 to 4 years postreatment were reported by davis and shariff with impromvents in success noted when microscope assisted intraorifice barrier were placed apical to the crakcs, occlusal reduction was performed postoperatively and full ocverage restorationswere placed expeditiously"

Awawdeh 2017

RCT therapy decreases reception to bite force. RCT have higher bite force

Walton 1984

fractures of teeth---> bacteria demostrated in fracture lines of fractured teeth. Fractures often contained debris and inflamatory mediators, Inflamamtion on edge of teeth which accounts for bone loss

branstrom 1986

hydrodynamic theory of pulp sensitivity

Mainkar and Kim 2018

Cold testing: Sensitivity 87% (nonvital) specificty: 84% (vital). overall cold is 84% accurate.

Heat testing Sensitvity .78(necrotic) Specfiicty .67 (vital) Heat .72% accurate

EPT .72 senstivity (necrotic) .93 specficity (vital). EPT 82% accurate

Pusle and LDF 97% accurate

Fayad 2012

Fractures: Midroot loss of bone with intact bone coronal and apical to defect, absence of the entire buccal plate, midroot radiolucency in area of post termination and space between the buccal or lingaul plate and the root srface

Sabeti, Chung 2024

Overall success: 78% and 86% for strict vs loose.

systematic review on ReTx success. Found things that influnce outcome include lesions

1) No lesion success healing/success rate: (98% vs 96% strict vs loose)
2) lesion success rate healing/success rate (75% vs 84% strict vs loose)

Lesion Size

1) less than 5mm or 65mm squared: (87% vs 93%)

2) larger than 5mm (62% vs 87%)

Filling Length

1) 0-2mm (83.8% vs 89%)

2) more than 2mm short (51% vs 72%) SS

3) Long 78% vs 94% SS

longer followup and retreat studies from later in 2020s had higher success rates

lin 2014

tooth extraction hazard ratio for the RCT with rubber dams was significantly lower than that observed for RCT without rubber dams (hazard ratio = 0.81; 95% confidence interval, 0.79-0.84).probability of initial RCT using rubber dams after 3.43 years (the mean observed time) was 90.3%, which was significantly greater than the 88.8% observed without the use of rubber dams (P < .0001).

Krell and Riveria 2007

only 21% of teeth that were cracked with RP ended up needing endo, typically within first six months

read 2014

ibuprofen can signifcantly affect the results of cold, percussion and palpation testing, whereas it does not affect bite force.

Nagaoka 1995

odontoblastic processes and dentinal fluid provide barriers to bacterial invasion into pulp in vital teeth. In nonvitial teeth these pathways are open for a bacteria invasion leading to eventually a infected tooth even in initial cases of asepctic necrosis assuming bacteria can find a way through intial enamel layer

(Gorni & Gagliani, 2004)

altered anatomy from intitial RCT treatment leads to successful outcomes in retreatment cases only 47% of the time, overall success was 69% and those with respected anatomy 86.8%

Mattison 1984

No difference in external root resorption in orthodontically treated teeth vs vital teeth in a cat study model at 6 months

Sjogren 1990

8-10yr recall

Vital cases: 96% success rate. Over-extended filling materials here are not problematic

Necrotic cases with lesion: 86% success rate. However this jumps to 90% if canal was instrumented to length and is only 69% in cases where they could not instrument to length

For N/PARL cases:

Obturation 2mm from apex: 94% success

Long: 76%

>2mm short: 68%

Retreatment with lesion: 62% success rate

Flare ups and AAA have no effect on long term success

Langeland 1977

No relation between radiographic lesions and patient symptoms. 14% of lesions contain bacteria

Bergenholtz 1977 and 1982

bacteria in the oral cavity can induce pulpal inflamation, 1982 showed that its leakage around restorations by bacteria that cause inflamation, not the materials themselves

Riccucci 2020

No histological, clinical, bacteriological difference in true vs. bay cysts. No reason bay cysts should heal and true cysts shouldnt. ALL associated with intraradicular infection. True cyst is not a self sustaining entity. CYST THEORIES CITED IN THIS PAPER

merdad 2011

ETT have higher caries risk than non-endodontically treated teeth with restorations

Caviedes-Bucheli 2017

Excessive occlusal forces reduce pulpal blood flow and oxygenation, stimulating angiogenesis through both direct effects of substance P on endothelial cells and fibroblasts and indirect effects mediated by inflammatory cells that release angiogenic growth factors. These newly formed blood vessels support pulp repair by supplying oxygen and nutrients, promoting collagen production, recruiting stem cells and inflammatory cells, and facilitating the formation of tertiary dentin as a defense mechanism against continued mechanical injury. If occlusal trauma persists beyond the pulp's reparative capacity, continued inflammation and vascular compromise may ultimately lead to pulp necrosis

Riccucci 2021

Symptomatic irreversible pulpitis consistently involves bacterial infection, not just inflammation. Every tooth in the study exhibited bacteria within pulp blood vessels. Infection remains concentrated in the coronal pulp, with no intravascular bacteria detected in the middle or apical root thirds. Reversible pulpitis does not have bacterial invasion

Ricucci 2006

Radiographs cannot be used to distingush cysts vs granulomas

Ricucci 2021 perio and pulp

Cementum is essential for protecting the pulps. In teeth with perio pockets and cementum loss pulp inflamation was seen

Sundqvist 1998

Well treated teeth have a high success rate in retreatment (74%). Larger lesions and positive cultures at time of obturation are associated with higher rates of failure. Most persistent infections are due to singular bacterial species, usually E. Facelis

Ricucci 2010

Apical periodontitis is a biofilm induced disease. Larger lesions/cystic lesions tend to have more biofilm representing a time dependent growth

Baumgartner 1991

Endodontic microbial communities progress from more areobic species to fewer anerobic (5 on average) species due to reduced oxidative potential over time as the infection progresses

Debelian 1995

Intrumenting beyond the apex has no effect on levels of transient bactermia which is induced on average about 44% of th time

Du 2014

6% bleach was more effective than 2% chx or bleach at killing E.F biofilms. Peak killing time was at 3 minutes with effects decreasing signficantly after 10 min. More mature biofilm were more resistent to solutions

Fabricius 2006

The key finding was that eliminating bacteria from the root canal system before permanent root filling was the most important factor for successful healing of periapical tissues, whereas the technical quality of the root filling alone had a limited effect if bacteria persisted.

Distel 2002

Enterococcus faecalis can survive intracanal medicaments by forming true biofilms, making it dramatically more resistant to disinfection and a major driver of persistent endodontic infections. This study provides direct SEM and confocal evidence that E. faecalis develops organized, mushroom‑shaped biofilm structures inside medicated root canals, even in the presence of calcium hydroxide—explaining why this organism is so difficult to eliminate in retreatment cases. CAOH paste kept biofilm away for 77 days

Sequira 2004

Candida is present in 21% of samples of teeth with infection

Ricucci and Bergenholtz 2004

bacteria are usually confined to the root canal space, Apical periodontitis is a host inflammatory response to infection originating within the root canal system the inflammatory lesion develops at the microbial–host tissue interface around the apical foramen, where bacterial antigens and virulence factors stimulate the host response rather than requiring extensive bacterial invasion of the periapical tissues. PA lesions not from bacteria themselves

Vital pulp tissue can be found in teeth testing necrotic. Thus clincal testing more closely indicates coronal pulp status rather than apical pulp status in some cases

clinical pulp testing reflects the condition of the coronal pulp rather than every portion of the root canal system.

Ricucci and Langeland 1998

overfilling with GP or SEALER is associated with peristent inflamation beyond apex, best healing occured when filling material is kept within minor constriction. DO NOT OVERFILL

Lateral canals and/or apical ramifications: (i) cannot be debrided mechanically or chemically (ii) when `filled', the injected material causes tissue destruction and inflammation. Radiographic demonstration of them does not mean excellence in endodontics.

Easlick 1951

Refuted focal theory of infection. Extractions of ETT do not routinely improve pt overall health

Sundqvist 1976

Refuted the theory of anchorsis. findings strongly supported that bacteria enter through: caries, coronal leakage, cracks, trauma with exposure, rather than via the bloodstream.

sterile necrotic pulps lack PA lesions

Krell 2018

Cracked teeth have a fairly high success rate (82%), which decreases signficantly when probing depths extend 5mm or more (35ish) or there is dual MMR and DMR cracks (62%). Pulpal and apical diagnosis also play a role in success rate but to a lesser degree, with necrotic cases and cases with lesions/sinus tracts having lower success rates

Peters 1994

EPT is more prone to false positives, cold more prone to false negatives (14% of pt over 50). Cold test in cervical buccal region for best results.

Chogle 2020

CT scans have a signficant effect on providers decison making regarding treatment (49% change in treatment decisions with CT) and etiological agents responsible for endodontic pathosis (54% change in ascribed etiological agent of pathosis)

Ee 2014

reoperative CBVT imaging provides additional information when compared with preoperative periapical radiographs, which may lead to treatment plan modifications in approximately 62% of the cases

Sjogren 1991

7 days of calcium hydroxide was sufficient to eliminate cultivable bacteria in the vast majority of infected canals. Must dress for at least 7 days

Siqueria and Lopez 1999

Review demonstrating that hydroxyl ion diffusion peaks over the first 2–3 weeks, while dentin and tissue fluids progressively buffer the alkaline environment, resulting in a gradual decline in antimicrobial effectiveness rather than an abrupt loss of activity."

Bystrom and Sundqvist 1985

The combination of EDTA followed by NaOCl was significantly more effective than NaOCl alone

Bacteria that survived instrumentation and irrigation rapidly repopulated the canal between appointments if no intracanal medicament was used.

• This finding became a major rationale for the use of calcium hydroxide as an interappointment dressing in infected cases

Teixeria 2005

1-minute final rinse with 15% EDTA followed by NaOCl removed the smear layer as effectively as 3 or 5 minutes in coronal 2/3rd and was moderately effective in apical 1/3. 3 min needed to fully clean apical 1/3rd.

Garberoglio 1994

Edta 3% as effective as 17% both able to remove smear layer in apical 3rd in as little as 30 seconds

Jones 1999

Large cotten pellet is most effective at transmitting endo ice cold to tooth for testing

Miller 2004, Hazard 2021

Miller: Cold testing through crowns mimics enamel conduction in PFM and all ceramic, Gold crowns respond quicker, Cold testing through crowns is accurate

Hazard: 91.5% diagnostic accuray of cold testing in normal crowns vs 86% in teeth with full coverage crowns

Aminoshare 2018

CBCT imaging was reported to have twice the odds of detecting a periapical lesion than traditional periapical radiography,

Kontakiotis 2019

The overall incidence of asymptomatic necrosis follwoing crown prep was

9%. Intact teeth had a significantly lower incidence of

pulp necrosis (5%) compared with preoperatively

structurally compromised teeth (13%)

Kontogiannis 2015

The key finding is that although uncommon (3.42%), lesions unrelated to pulpal necrosis can closely resemble periapical inflammatory lesions and may include aggressive odontogenic cysts, tumors, and even malignant diseases. Clinically, the study supports routine histopathologic examination of tissue removed from periapical lesions, particularly when lesions are large, to ensure that important non-endodontic pathoses are not overlooked.

Chai & Tamse 2015

The isthmus is a major structural factor that greatly increases the susceptibility of two-canal roots to vertical root fracture by acting as a natural crack that promotes fracture propagation. Presence of an isthmus dramatically reduced the apical force required to produce vertical root fracture, decreasing the maximum fracture load from approximately 50 N in roots without an isthmus to approximately 10 N when an isthmus was present (within the range of forces used clinically during gutta-percha condensation)

Haupt 2023

systematic review on VRF: posts were not correlated with VRF, whereas presence of sinus tracts, increased probing depths, swelling/abscess, and tenderness to percussion were all asscoaited with VRF

Estrela 2002

Sodium hypocholrite is an ideal endodontic irrigating solution as its soaponfication and amino acid neutralization reactions enable it to dissolve pulpal tissue while its choloramination reactions, free CL- ions and high pH promote irrversible oxidiation and inhibition of bacterial enzymes and promote cell wall breakdown and baceterial cellular metabolism collapse.

Soaponfication reaction in which fatty acids are dissolved into fatty salts and gycerol which in addition to tissue dissolution aids in reducing surface tension of the overall solution

amino acid neutralization reaction in which it reacts with amino acids forming water and salts as byproducts and destorying amino acids choloraminotion reaction in which Hypochlorous acid, a substance present in sodium hypochlorite solution, when in contact with organic tissue acts as a solvent, releases chlorine that,

combined with the protein amino group, forms chloramines. chloramines interfere in cell metabolism and Chlorine (strong oxidant) presents antimicrobial action inhibiting bacterial enzymes leading to an irreversible oxidation of SH groups

(sulphydryl group) of essential bacterial enzymes

4) the high pH of sodium hypochlorite interferes in the cytoplasmic membrane integrity with an irreversible enzymatic inhibition, biosynthetic alterations in cellular metabolism and phospholipid degradation observed in lipidic peroxidation.

Kulild 1990

Under ideal in vitro conditions, 90.2% of first molars and 78.2% of second molars had a locatable ML canal. These have seperate orifice in over 54% of cases. On average these orifices are usually 1-3mm P from MB1

Lv, Li 2026

88% success (mantianed vitality) with BC putty DPC on SIP teeth at 36 months (obtained hemostasis in 2 min or less with less than 1mm exposure). Mean pt age 38yrs. Higher failure rates with those pt that had more pain reported beforehand

Bystrom and Sundqvist 1981

Mechanical instrumentation with saline alone is not enough to render canals bacterial free. in 1983 they found that Adding .5% bleach helped but still left canals with microbial loads. CAOH helped reduce bacterial loads to the point where they may cultivate negative upon a second visit. Bacteria are responsible for apical periodontitis and we cannot rely on mechanical instrumentation alone but need chemical disinfection as well

Sathorn 2005 and 2008

• Vital cases: Single-visit treatment appears to be entirely reasonable.

• Necrotic cases with apical periodontitis: Evidence does not demonstrate a clear healing advantage for multiple visits.

• Complex infections, persistent exudation, swelling, or uncertain disinfection: Multiple visits may still be justified based on clinical judgment.

• There is no substantial evidence that either single-visit or multiple-visit treatment is superior with respect to treatment success or postoperative complications. Long term success rates were similar in both groups and rates of pain or flareups were similar as well whether you medicate or not

• TWO STEP BASED ON CLINICAL PRESENTATION NO HARD AND FAST RULES
  
  2008: NOT Enough literature to show difference in flareup rates in one vs two steps

Figini 2008

There is no strong evidence that multiple-visit root canal treatment results in better healing than single-visit treatment.

Wu 2002

Coronal leakage matters. Restorative quality matters. However a good restoration cannot reliably compensate for poor endodontic treatment, whereas a high-quality root canal filling can often maintain periapical health despite a less-than-ideal restoration.

Challanged Trope and Ray 1995 that advocated coronal restoration was more important that quality endo

Showed that enlargement of the apical root canalsystem did not ensure removal of the inner layer ofdentine from all apical root canal walls or all infectednecrotic pulp tissue

Schroeder 2002

Pre-coronal flaring and SLA had little effect on altering WL. Even in cases of severe curves the overall change was on average .2mm. THus WL taken before or after flaring is equally valid from a clinical perspective.

Aminosharie 2015

contemporary chemomechanical debridement techniques with canal enlargement techniques do not eliminate bacteria during root canaltreatment at any size, there yet remains to be an "ideal" size to shape too. RCT success appears to be related to more than simple mechanical removal of bacterial but is a complex interaction of bacterial species, mechanical removal and adequte disinfection

Ravanshad 2004

EAL appears to be more accurate in determining WL than radiographs alone. It protects the patient from excessive radation and can also help limit the rate of over-instrumentation when compared to using a WL as determined from radiographs alone

Setzer 2010 Meta Analysis

use of EMS techiques (micrscope, MTA, ultrasonic retroprep) had 94% success rate at 12+ months compared to 59% for traditional surgery (bur retroprep with amaglam and loupes). 1.58OR for success with EMS compared to traditional

NG 2011

success odds as defined as absence of lesion for primary tx was 82% and for retreatment was 80%

1) roots with lesions had lower success rates (14% decrease per 1mm increase in lesion size)
2) each mm short from patent decreased success rates by 12% from 1-2mm short patency vs more than 2mm
Patency had a 2.22 OR of increasing success compared to not getting patent (83vs 76%)
3) EDTA had no effect on primary tx success but did increase success rate in retreatments (2.2 OR)

4) good coronal restoration increased success rate by 11 fold
5) As long as you acheive patency broken files in canal spaces do not matter
6) Sinus tract and intra-appt flareups assocaited with lower overall success rates
7) Chx with bleach assocaited with lower success rates

8)MAF smaller or larger than 30 was not an indepentdent predictor of success rate (actually showed lower success rate with larger MAF)

Kokkas 2004

emoval of the smear layer allows for sealer penetration into dentinal tubules. This may be important for increasing sealer adhesion/decreasing microleakage and possibly increasing bacterial contact with bacertiastatic and bacterialcidal sealers.

Texeria 2003. Estrela 2015

Isthmuses most common 3-5mm from apex in UM and 3-6mm in Mesial root of lower molars. maxillary first: 30%, mandibular 60%

Estrela: 60.8% of maxillary first have isthmuses (94% in MB)

88% of lower first molars have isthmus (60/40 split)

Neaverth 1987

77% percent of maxillary first molars have two canals, 62% have seperate foramina

Wolcott 2005

CLINICALLY Overall the MB2 canal was found in 2133 (60%) first molars, and 712 (35%) second molars. This was for neogiatable canals that could get to length or within 5mm of MB1 terminus. Higher MB2 incidence in retreatments indicates many MB2 canals are missed during initial therapy.

Azim 2015 Nosrat 2015

Azim: 6% had MM in lower molars, 46% of the time with troughing

Nosart: 20% of lower molars had middle mesial. more common in younger patients incidence was less than 4% in over 40yo

Calt 2002

10 min of EDTA had signficant breakdownn and erosin of dentin whereas 1 min showed mild to minimal edta influnced erosion

Foster and Kulild 1993

Smear layer removal allows more CA to diffuse to external root surface and elevated external root surface PH more this is important for halting trauma induced resoprtion

Arias-Moliz et al. 2016

Bleach can be inactivated by dentin powder in as little as sixty seconds. THus there is a need for constant replenishment. 1% bleach was completely inactivated in less than 3 min.

2.5% was less than effected

Zou 2010

Heat had no effect on bleach penetration depth into dentinal tubules. Time was the most important determinate with maximium penetration being reached at 20 min with 6% bleach (300microns). 1% at 2min was only 77micron.

200um at 5 min with 6%

Caldwell 1976

mean WL reduction after instrumentation was .35mm, most pronounced in MB roots

Davis 2002

NiTI showed .22mm reduction in WL after instrumentation, this was even less after precornal flaring .14mm

Gates and SS showed larger reduction of .48 ±.3

Piasecki 2016

0.5mm on Apex locator is consistent with minor constriction

Kennedy 1986

Removal of smear layer greatly reduced apical leakage

Virdee 2020

Manual dynamic activation enabled up to 400um of bleach pentration at 20 min and 5% this was as good or better than PUI and sonic activation, especisally in the apical third. All three were better than needle irrigation alone

Van Hassel 1971

paper on Intrapulpal tissue pressure found that on average pulpal tissue pressure is approximately 25mm Hg in healthy pulps, however, this can be localized, with areas of inflamed pulp showing signficantly higher tissue pressure. Showed localized increases up to 40+ mmHg with localized trauma, however the apical areas did not show a corresponding rate of pressure elevation, this helped push back upon the pulp strangulation theory that posulated a single area of pulpal inflamation can raise IPP so much as to lead to pulpal necrosis rapidly.

Heyerras 1999

The dental pulp is a low compliance system which causes increased risk of pulpal necrosis when inflammation triggers increased fluid pressures within the pulp. However, the low compliance nature of the pulp is also somewhat beneficial as elevated pressures in inflammatory conditions precipitates outward fluid flow through dentinal tubules inhibiting the influx of toxins into the pulpal space.

WHite 1997

2% CHX has prolonged antibacterial effects within instrumented root canals spaces that extend up to at least 72 hours post treatment. Clinicians should evaluate these findings and perhaps incorperate CHX rinses into their treatment protocols as it offers prolonged bacterialcidal activity which bleach alone cannot offer

Brito 2009

while the endovac and endoactivator have been shown in some studies to produce "cleaner canals" with respect to removal of debris and CAOH in other studies, this study showed that these adjunctive irrigation techinques do not impart any additional antibacterial effects within the root canal spaces.

Keinan 2022

orthodontic treatment had no risk of higher failure in teeth that had trauma and underwent apexification at 5 years. Orthodontic group did have loss of .33mm that was absent in non-ortho group which had a .1mm growth.

Ricucci 2016

No matter the type of sealer, overextension of it into the periradicular space did not impact healing rates. These findings help support the fact that being long in vital cases has no influnce on success rate, as 100% of these cases were successful. Additionally ZOE sealers show much higher rates of resorption beyond and into the apical area than do resin and caoh based sealers. This is interesting, as it suggests that these sealers have the potential to induce lower long-term inflamation at the root apex in cases of overfill

Sabeti 2006

This has stat testing errors and sampling is questionable. They also make misleading claims hwover Sabeti claims that root canal disinfection is sufficent for healing of PARL lesions independent of whether the root canal is obutrated or not, however they draw from a very small clinical sample so the results of this study should be taken with caution. IN addition he advocates for obturating canals because we can never fully assure we have completely disinfected canals and thus its important that we entomb any remaining bacteria that may be present.

harrison 1983

: Intra-appointment pain is the biggest predictor of post-op pain when two stepping teeth. Post-op pain is not uncome but typically does not extend longer than 7 days. Irrigating with bleach and medicating with formo does not cause painful inflamation post-op and is actually associated with lower incidences of post-op pain than using saline and no medication. Finally while not true for all scenerios with respect to vital teeth, extrusion of material is accompanied by higher levels of pain than when obturation materials are kept entirely within the canal space

Ng 2005

Predictors for post op pain in teeth with lesions included smaller lesion size (3mm although this was non-signficant), being female (57% higher odds), single visit treatment and posterior teeth. Did not find an association between pre-op pain and post-op pain. Also found intra-appt pain was a predictor of post-op pain like harrison 1983. 40% incidence post op pain at day one or two

Quero 2020

86% same anatomy across lower lateral incisors. Can use contra lateral teeth to assess anatomy on tooth it radiographs make it unclear

Tronstad 1981

The key takeaway is that calcium hydroxide diffused through dentinal tissues and substantially increased their pH, including at areas of exposed dentin associated with inflammatory root resorption. The study therefore supports the concept that calcium hydroxide can alter the local environment of resorption areas in a manner that may inhibit continued resorption and stimulate repair, although the authors could not determine the relative importance of pH elevation compared with other effects of calcium hydroxide.

Gordon 1981

NaOCl dissolves both vital and necrotic pulp tissue, with higher concentrations producing faster tissue dissolution. 3% and 5% NaOCl dissolved ~75% of vital tissue within 2 minutes,

while even 1% dissolved ~90% of necrotic tissue by 5 minutes, emphasizing that both concentration and contact time determine tissue dissolution.

Lee 2011

Flareups did not effect long term outcome