Microbiological evaluation of one- and two-visit endodontic treatment of teeth with apical periodontitis: a randomized clinical trial

By Kvist T, Molander A, Dahlén G, Reit C

Date: 06/2005
Journal: JOE


Purpose: to compare the microbiological outcome of a one-visit treatment, including a 10-min intraappointment dressing with 5% iodine-potassium-iodide IPI, after removal of the smear layer with a standard two-visit procedure, including an interappointment dressing with CH

•N= 84 patients (96 teeth), Inclusion: Asymptomatic teeth with necrotic pulps and apical periodontitis


•the teeth were isolated, disinfected & accessed and sampling fluid (VMGA I) was introduced and the canals were enlarged with rotary and hand instruments up to ISO#20, then the fluid was absorbed with charcoal points (initial sample).

•the canals were further enlarged to #40 or #60 with 0.5% NaOCl irrigation. NaOCl was inactivated and sampling fluid was introduced intra-canal and absorbed with points (post-instrumentation sample).

•One visit group: the canals were filled with 5% IPI for 10 min. IPI was then inactivated and the canals were sampled and obturated (post-medication sample).

•Two visits group: The canals were filled with CaOH for 1 week. CaOH was then removed and canals sampled.

Most highlighted Results: 

•Initial sampling demonstrated the presence of microorganisms in 98% of the teeth. Postinstrumentation sampling showed reduction of microbiota. Antibacterial dressing further reduced the number of teeth with surviving microbes.

•In the postmedication samples, residual microorganisms were recovered in 29% of the one-visit teeth and in 36% of the two-visit treated teeth with No statistically significant differences between the groups.

Clinical significance: 

from a microbiological point of view, one visit tx performed as effective as 2 visits tx.