Treatment choices for negative outcomes with non-surgical root canal treatment: non-surgical retreatment vs. surgical retreatment vs. implants STEVEN A. COHN Endodontic Topics 2005

The primary reason for a negative outcome with endodontic treatment is the persistence of bacteria within the intricacies of the root canal system. Failure may also be attributed to the persistence of bacteria in the periapical tissues, foreign body reactions to overfilled root canals, and the presence of cysts.

5 levels of evidence – Prospective randomized-controlled trials (RCT) considered the highest level of evidence (LOE 1). No papers dealing with non-surgical retreatment and surgical revision that reach the highest LOE. The primary consideration is the patient’s values and expectations.

Non-surgical retreatment The incidence of periapical lesions following root canal procedures surveyed in many countries is 20–60%.

Non-surgical retreatment Apical periodontitis – apical periodontitis is the most important variable influencing a positive outcome with non-surgical retreatment. – Hepworth&Friedman: the retreatment of teeth without periapical lesions has a positive outcome of 95%, but in their study and others, this declines to 56– 84% in the presence of a periapical lesion. – The true negative outcome rate may be only 10–16%.

Non-surgical retreatment Role of primary endodontic treatment – Sjøgren found that 94% of periapical lesions healed when the root filling was within 2mm of the apex, a significant difference when compared with overfilled canals (76%) and those more than 2mm short of the apex (68%).

Non-surgical retreatment Bacterial and technical considerations – Farzanehet found that a positive outcome was most influenced by the presence of a preoperative perforation. – Other negative factors were the quality of the root filling, the lack of a final restoration, and preoperative apical periodontitis. The overall success (or ‘healed’)rate was 81. – 93% when asymptomatic and functional teeth were included.

Reference set of radiographs with corresponding line drawings and their associated PAI score

Occlusion – The role of the occlusion following endodontic treatment requires further investigation

Restoration – The quality of the restoration affects the outcome because of the possibility of leakage. – Teeth not crowned following endodontic treatment were lost at 6 times the rate of those teeth that did receive crowns.

Outcome of periradicular surgery Surgical retreatment – Positive outcomes for surgical retreatment in excess of 90% can be achieved with careful case selection and a skilled and experienced operator

Outcome of periradicular surgery Lesion size and characteristics – No clear consensus that small (less 5 mm) lesions heal more favorably than larger lesions Tooth location – be less important than the access to it and the anatomy of the roots in determining a successful outcome

Outcome of periradicular surgery Preoperative symptoms – Symptoms do not appear to affect the outcome of surgery Age and gender – Neither the age nor the sex of the patient appears to influence the outcome of surgery

Outcome of periradicular surgery Quality of the root filling – Non-surgical retreatment of the root canals before surgery improves the prognosis for surgery – Short root fillings had a better outcome then roots filled to the apex or overfilled

Outcome of periradicular surgery Repeat surgery – A repeat of surgery is associated with a worse outcome than surgery performed the first time Resection – Resection of 3mm is considered sufficient to eliminate apical pathology Root-end filling and materials – IRM and MTA no significant diff.

Outcome of periradicular surgery Operator skill – The complete healing rate in the endodontic unit was approximately double that of the oral surgery department.

Intentional replantation Intentional replantation is a viable alternative to tooth extraction in selected cases.

Transplantation – Endodontic treatment is indicated for teeth with closed apices, usually within a month after transplantation. The prognosis for both closed and open apices is considered favorable

Endodontics or implants? Implant studies - when the criteria of EBD are applied, there are no papers that reach the highest level of evidence.

Ruskin state that an immediate implant has a more predictable outcome than an endodontically treated tooth as a basis for restorative dentistry. – “The best candidate for endodontic treatment is a single rooted tooth with an intact crown that has become devitalized due to trauma, and that also fulfills an esthetic need.”

Endodontics and implants: ‘success’ vs. ‘survival’ – concept of ‘survival’ is applied to implant studies – 1.5 million teeth from an insurance company database. The treatments were provided both by general dentists and endodontists, and a 97% retention rate followed up for 8 years was reported – the high success rates for implants may not be duplicated at the general practitioner level

Indications for an implant Root resection? – Langer reported a 38% failure rate of 100 molar teeth that had undergone a root resection – Blömlof reported on a 10-year follow-up of root- resected molars compared with root-filled single rooted teeth. The survival rate was similar.

CDA Journal, vol 36, 2008

The preliminary electronic and manual searches identifed 5,346 endodontic and 4,361 dental implant studies. – Inclusion criterias: At least 25 cases with a minimum two-year follow-up (endodontics - from obturation time; implant - from placement); with treatment units described as being single individual, implant-supported restorations, and/or endodontically treated teeth – Exlusion criterias: did not define criteria for success/survival outcomes, if they reported on treatments no longer used in practice, or if the patients were described as having moderate or severe periodontal disease

Following full-text review, 24 endodontic, and 46 implant studies were included

Implant success

Endodontic success

Implant survival

Endodontic survival

Retrospective cross sectional comparison of initial nonsurgical endodontic treatment and single-tooth implants. Doyle SL, Hodges JS, Pesun IJ, Law AS, Bowles WR. J Endod Sep;32(9):822-7.

Endodontics vs implant Compared 196 implant restorations and 196 matched initial nonsurgical root canal treatment (NSRCT) teeth in patients for four possible outcomes - success, survival, survival with subsequent treatment intervention and failure

Endodontics vs implant Doyle SL, Hodges JS, Pesun IJ, Law AS, Bowles WR. Retrospective cross sectional comparison of initial nonsurgical endodontic treatment and single-tooth implants. J Endod Sep;32(9): NSRCT outcomes were affected by periradicular periodontitis (p = 0.001), post placement (p = 0.013), and overfilling (p = 0.003).

Endodontics vs implant Estimated fraction not failing at each recall time