No abstract

The purpose of this study is to evaluate the effect of a bioactive glass-based root canal sealer, Nishika Canal Sealer BG (CS-BG), on the incidence of postoperative pain (PP) after root canal obturation (RCO). Eleven dentists performed pulpectomy or infected root canal treatments for 555 teeth. During RCO, CS-BG was used. After RCO, the rate of PP and the factors affecting PP (pain during RCO and pain immediately after RCO) were analyzed. PP was observed in eight teeth (1.5%), and within 7 days after RCO, there were no teeth with pain. In these teeth with PP, there was a significant difference in the occurrence of pain during RCO, but not in the occurrence of pain immediately after RCO, when compared with pulpectomy and infected root canal treatment. These clinical results show that CS-BG has an excellent biocompatibility, and can suppress the distress of patients during RCO.

In atomic systems for which the total oscillator strength of excitations from the ground state is dominated by the transition to the lowest resonance level, the f -sum rule provides a bracketing inequality connecting the lifetime τ of that level to the dipole polarizability α d . This relationship has been used previously to deduce α d from τ . It is shown here that improved spectroscopic accuracies now permit this procedure to be inverted, with τ deduced from a value for α d obtained spectroscopically using the core polarization model. A similar quantitative relationship exists connecting the nonadiabatic correlation factor β to τ , and thus also to α d . The method is applied to a recent measurement of α d for Kr 6+ to obtain the values τ (4s4p 1 P 1 ) = 0.096 ± 0.003 ns and β(Kr 6+ ) = 1.71 ± 0.03a 5 0 . It is shown that the use of this method to make precision lifetime determinations for a small number of ions in an isoelectronic sequence permits the exploitation of observed semiempirical regularities to specify the lifetimes of all ions in that sequence.

This system can be considered as a further step towards facilitating non-invasive and contactless systems in clinical practice.

No abstract