INFLUENCE OF SODIUM-HYPOCHLORITE ON THE PERMEABILITY AND STRUCTURE OFCERVICAL HUMAN DENTIN

The effect of 5% sodium hypochlorite and 35% hydrogen peroxide on dent ine samples in vitro was investigated. It was demonstrated that both 5 % NaOCl and 35% H2O2 depletes the dentine, which can be recorded as we ight loss. Sodium hypochlorite removes approximately 14% of dry weight from dentine samples in 24 h; hydrogen peroxide is half as destructiv e. The hydraulic conductance (L(p)) of dentine after treatment with Na OCl is increased over 100%. It is suggested that the use of high conce ntrations of sodium hypochlorite during root canal treatment may negat ively affect the integrity of the root canal wall thereby allowing inc reased access of caustic bleaching fluids to cervical vital tissues.