L22. Endodontic Failure Flashcards
How is the success of endodontics measured (by the ESE)?
- RCT should be assessed at least after 1 year, and subsequently as required (generally 6 months following tx);
- Absence of pain, swelling and other symptoms;
- No sinus tract;
- No loss of function;
- Radiological evidence of a normal PDL.
If radiographic changes stay the same size or has only diminished in size, how long should a post-tx follow up continue?
Up to 4 years
after this time - radiolucency considered as post treatment disease
What signs might suggest RCT has had an unfavourable outcome?
- Tooth is associated with signs and symptoms of infection;
- A radiographic lesion has appeared subsequent to tx or a pre-existing lesion has increased in size;
- A lesion has remained the same size or has only diminished in size during the 4-year assessment period;
- Signs of continuing root resorption are present.
In these situations - further tx required
N.B. Irregular mineralisation of PDL on a radiograph might suggest healing via scar tissue formation
When based on strict criteria (ESE and radiographic) for endodontic outcome, what is the approximate success rate of RCT?
75%
When based on loose criteria (e.g. tooth retained) for endodontic outcome, what is the approximate success rate of RCT?
85%
What is a technical success but biological failure?
- Good obturation via radiograph inc. correct working length, density etc.;
- BUT persistence of periapical radiolucency.
What is a biological success but technical failure?
- Issues with obturation via radiograph e.g. WL cut short, voids etc.;
- BUT resolution of pathology.
What pre-op factors contribute to success?
- Vital v non-vital pulp;
- Periapical lesion v no lesion;
- Tooth type;
- Age;
- Gender.
What operative factors contribute to success?
- Filling within 2mm of radiographic apex;
- Condensation of root filling, with no voids;
- Good quality coronal restoration.
What can happen if filling of a RCT is short?
Indicates inadequate seal/ disinfection
What can happen if a filling of a RCT is long?
- Destroyed/ open apical constriction;
- GP in periradicular tissues;
- GP in maxillary sinus.
What additional factors can contribute to the success of treatment?
- Presence of a sinus;
- Increased lesion size;
- No perforation;
- Getting patency (access to entire canal system);
- Penultimate rinse with EDTA (reRCT);
- Avoiding mixing CHX and NaOCl;
- Absence of flare up.
In what teeth are canals commonly missed?
Upper 6s (usually two MBs)
What is the Law of Symmetry I?
Orifices of the canals are equidistant from a line dram in a medial-distal direction through the pup-chamber floor
(except maxillary molars)
What is the Law of Symmetry II?
Orifices of the canals lie on a line perpendicular to a line drawn in a mesial-distal direction across the centre of the floor of the pulp chamber
(except for maxillary molars)
