Under the conditions of these in vitro leakage studies , it is concluded that smear layer removal improves the fluid-tight seal of the root canal system whereas other factors such as the obturation technique or the sealer , did not produce significant effects
The purpose of this systematic review was to determine whether smear layer removal reduces leakage of obturated human teeth in vitro .
Effect of dentin treatment on in vitro root tubule bacterial invasion.
In light of the in vitro S. sanguis bacterial migration observed deep into root dentin , an in vitro system was developed to determine the viability of these bacteria at the end of migration . Also of interest is whether the smear layer formed during root canal instrumentation modifies migration into root dentinal tubules . Forty-eight bovine root dentin sample s were r and omly split into two groups . Group 1 dentin blocks were not instrumented and were treated with 17 % ethylenediamine tetraacetic acid and 2.5 % sodium hypochlorite for 4 minutes in an ultrasonic bath Group 2 root canals were conventionally instrumented . The smear layer formed was not removed . Dentin blocks were inoculated with a S. sanguis National Collection of Type Culture 7863 suspension . Each sample was immersed in a receiver broth , incubated at 37 degrees C , and checked daily for 14 days . After a 14-day incubation period , group 1 S. sanguis cells remained viable and capable of inoculating the receiver medium after migration through the tubules . Group 2 cells , where the smear layer was intact , revealed an absence of S. sanguis migration in 88 % of the cases . It is therefore plausible that smear layer on canal walls limits S. sanguis penetration of dentinal tubules in vitro
Under the conditions of these in vitro leakage studies , it is concluded that smear layer removal improves the fluid-tight seal of the root canal system whereas other factors such as the obturation technique or the sealer , did not produce significant effects
The purpose of this systematic review was to determine whether smear layer removal reduces leakage of obturated human teeth in vitro .