James P. Walker, DDS, PC
Tualatin Endodontics ®                    503-885-1899
Specialist in Endodontics: microscopic non-surgical and surgical endodontics. Portland Oregon

Abstracts & Treatment Resources

Topic: One vs Two Appointment Molar Treatment

One- versus Two-visit Endodontic Treatment of Teeth with Apical Periodontitis: A Histobacteriologic Study. Vera j, Siqueira J, Ricucci D, Loghin S., Fernandez N, Flores B, Cruz A. JOE 2012 Vol 38, No. 8:1040-1052.

Methods: Necrotic teeth with chronic apical periodontitis were treated in one or two visits. The teeth of both groups were extracted at one week and evaluated with light microscopy.
One appointment protocol: 6 mesial roots of mandibular molars were instrumented, irrigated for a minimum of 45 minutes with 5% NaOCl, with maintenance of patency and smear layer removal, and final irrigation with 2% chlorhexidine, and then obturated with gutta-percha and Pulp Canal Sealer.
Two appointment protocol (7 mandibular molar mesial roots): Same as one appointment treatment, but medicated with CaOH for one week. At second appointment canals were irrigated with 5% NaOCl and a final rinse with 2% chlorhexidine.

Results:
None of the 1-visit group were rendered bacterial free. Four of the six roots had bacteria in the main canals in the middle and apical thirds. All six had bacteria in the apical third. Bacteria were in the dentinal tubules and isthmuses in five of the six specimens. Bacterial penetration reached varying depths sometimes reaching more than two thirds of the dentin thickness.

Two Visit Group: Two of the seven roots were rendered bacterial free. No bacteria were seen in the dentinal tubules of the main canals in all seven roots.

Conclusions:
“The present findings indicate that the root canal systems of teeth treated in 2 visits with 1-week calcium hydroxide inter-appointment medication had an improved microbiological status when compared with teeth treated in a single visit.”
“The present findings confirm that it requires time for the therapeutic antibacterial procedures to affect bacteria located in anatomic complexities and then maximize bacterial reduction to levels that cannot be achieved in 1 visit.”