Rubber Dam Use during Post Placement Influences the Success of Root Canal–treated Teeth

By Goldfein J, Speirs C, Finkelman M, Amato R.

Date: 01/2013
Journal: JOE


  • To investigate whether the use of rubber dam in the placement of a prefabricated post and core impacts the success of root canal–treated teeth.


  • N= 185 patients (204 teeth, treated at Tufts) in 2008-2011
  • Exclusion criteria: Teeth with a periapical lesion beyond that of a widened PDL at the time of root canal treatment and post placement (PAI 3–5) 2. Patients w/o a follow-up radiograph of at least 6 months 3. Teeth extracted w/in the first 6 months after RCT 4. Cases in which procedural errors (perforation, separated file, and transportation) occurred during post placement that resulted in extraction or decreased prognosis 5. Teeth with development anomalies, immature roots, and crown or root fracture
  • Inclusion criteria: 1. Records had to be available 2. The tooth did not have a periapical lesion or a widened periodontal ligament (PDL) greater than twice the width of an adjacent healthy PDL. 3. Only endodontic cases of good quality were selected for evaluation.
  • Positive/negative control: x
  • Control & Design: Treatment can be assumed to have been done with techniques being taught at the time, which included step-back hand instrumentation with LC for the patients treated before fall 2010 and rotary instrumentation with continuous wave vertical condensation afterward. Data collection by 2 authors, consisting of examination  of pre, post, and recall radiographs and charting. Third observer was blinded regarding RD use.
  • Criteria of evaluation: Development of PARL, PDL space wider than 2x’s normal, evidence of EXT at recall


  • Average recall 2.7 years
  • 26 patients (30 teeth) received post w/RD
  • 159 patients (174 teeth) post placed w/o RD
  • w/o RD: 74% considered success at f/u
  • w/RD: 93% considered success at f/u
  • Statistically significant results

Clinical Significance:

The results of this study emphasize the importance of a quality aseptic technique in restoring root canal–treated teeth to preserve an uncontaminated environment within the root canal system.