Retreatment Flashcards
success rate of endodontic therapy
has been reported all over the place
from 94.8% to as low as 53%
follow up in years in the studies is an important aspect
success of retreatment
80 ish(83%)
so re-treatment can have a lower success rate
follow up period for retreatment
better results if longer because sometimes healing is longer
healing in progress –> healing complete
how to/ ways to evaluate endodontic success
- clinical success
- radiographic success
- histological success
- follow-up period
clinical success is represented by?
ABSENCE OF SIGNS AND SYMPTOMS
- no spontaneous pain
- negative o percussion
- negative to palpation
- absence of sinus tract
- absence of swelling
radiographic success
contours, width, and structure of PDL are normal
- follow PDL space and want intact lamina dura
cannot be success on its own
follow-up period importance
how long endodontic treatment should be followed up?
1 year is minimum!! -
follow up period up to 4 years is desirable
(2-3 weeks if dealing with sinus tract )
when assessing tooth that ay need re-treatment what is important to ask and do?
ask when it was treated
PROBE– eliminate perio as reason
etiology of failure
presence of infection in root canal system
(Usually limited to root canal space) – but if established can extend
BACTERIAL INFECTION
triad of success
- diagnosis
- cleaning, shaping, and 3-D obturation, (good treatment)
- coronal restoration
diagnosis importance
radiographs and make sure this is right
- clinical and radiographic examsm
like signs and sympoms point to endo but actually could be something like a palatal groove and localized bone loss – which is a perio problem
radiogrpahic importance of diagnosis after treatment
look back at radiographs – could think failing but actually getting better when compared to old radiographs
goal of cleaning shaping and obturating
- eliminate organic material and bacteria from root canal system
- prevent future bacterial contamination and infection
- seal any remaining bacteria within the root canal system (place a restoration as soon as practically possible)
have to get all canals
number one failure for RTC
missed a canal
breakdown of post endodontic coronal restroration
- temp restoration
- post preparation
- proper coronal restoration
- quality of coronal restoration
temporary restoration requirements and breakdown
- must have divergent access prep
- thickness must be 4mm (depth - inside access cavity)
- cavit temporary recommended
- immediate permanent restoration
describe post preparation
- use of rubber dam
- maintain 5mm of apical gutta percha – so dont compromise the apical seal
- heat carrier followed by rotary instrument (gates glidden burs)
amount of gutta percha to leave if preparing for a post space
maintain 5mm of apical gutta percha – so dont compromise the apical seal
(ideally) to establish a good apical seal
failure to adequately and properly restore endodontically treated teeth may result in what?
vertical fracture of tooth structure
clinical success rate with maxillary anteriors with crown and no crown
ateriors
crown
- 87.5%
no crown
85.4%
clinical success rate of maxillary premolars with crown and no crown
crown
- 93.9%
no crown
- 56%
clinical success rate of maxillary molars with crown and no crown
crown
- 97.8%
no crown
-50%
why is the success rate go down so much without crown restoration
FRACTURE – so all restoration teeth with endo need cuspal coverage
coverage requirements in anterior vs posterior
all posterior teeth that have received endodontic treatment require CUSPAL COVERAGE
not all anterior teeth require crowns
what is more important the quality of endo treatment or the quality of coronal restoratino? exaplain
literature points towards need for restoration
technical quality of restoration is more important than the technical quality of the endo for the apical periodontal health
good endo and poor restoration? vs poor endo and good restoration?
success rate with poor endo and good resto = 66.7%
success rate with good endo and poor restoration is 44.1%
coronal leakage
likely due to insufficient coronal coverage
a tooth with previous RCT 2 years ago and comes in asymptomatic until 1 week ago with percussion, palpation and swelling could be due to?
coronal leakage
biological factors affecting endodontic success
- apical pathosis (radiolucency)
- pulp vitality
- apical resorption
- patient’s general health
- pre and post -operative pain
therapeutic factors affecting prognosis
- obturation quality
- intra-canal medication
- number of treatment sessions
- procedural periapical disturbances
- type of filling material
debatable importance of what factors affecting prognosis?
- tooth type
- age
- gender
- ethnicity
- size of lesion
pulp vitality in terms of success?
vital teeth have higher success rate than necrotic teeth
apical pathosis in terms of success?
teeth with peri-apical lesions have lower success than teeth without lesions
radiolucency!! – means pulpal infection
T/F bacteria present at the time of obturation with decerase the success rate
TRUE
number of appointments best? why?
2 – for necrotic cases
use of calcium hydroxide paste as an intra-canal medicament between visits helps eliminate infection from root canal system
(vital cases can be done in one visit)
calcium hydroxide?
placed after first appointment in root canal treatment
number one reason for endo failure
missed canal
main reasons for endo failure
inadequate treatment
- missed canals
- calcified canals
- presence of obstructions
- perforations
- coronal leakage
- combination of factors
two types of retreatment
- surgical
2. conventional
if endo was failure and you cannot access the canals what is treatment?
SURGERY
if endo was failure and you can access the canals what is treatment?
retreatment
most commonly missed canals in mandibular and maxillary?
- mandibular molar 2nd distal canal (and sometimes there is a rd one here too)
- 3rd mesial canal in the mandibular molar
maxillary
- maxillary molar 2nd mesio-buccal canal
and 2nd disto-buccal canal
major reasons as to why endo surgery would be needed?
- anatomical reasons (complex)
- bacteriological reasons (advanced infections) - established bacterial infection in root canal system and beyond
- histological reasons (like a cyst maybe) – like radicualr cysts
minimum follow up period?
ONE year
t/f conventional retreatment should be attempted whenever possible before surgical intervention
TRUE
