An in vitro comparison of three delivery techniques for obturation of root canals in primary molars

This in vitro study evaluated the efficacy of three different obturation techniques with regards to quality of two filling pastes-Ca(OH)₂/iodoform syringe paste and zinc oxide eugenol paste in primary molars.

Root canals of 45 extracted primary molars were prepared and randomly divided into three groups of 15 teeth each. Group A-canals were filled with Ca(OH)₂/iodoform syringe paste, Group B-zinc oxide eugenol paste with handheld lentulo spiral and Group C-zinc oxide eugenol paste with rotary lentulo spiral. The quality of filled root canals was evaluated with conventional radiography in antero-posterior and lateral dimensions.

There were significant differences between all groups in the presence of voids (p = 0.03) and length of filling (p = 0.002). Half of the sampled teeth in handheld lentulo spiral group had voids in the filled canals, while 80% of the teeth filled with Ca(OH)₂/iodoform syringe resulted in overfilling of the paste.

All three delivery methods for the obturation of primary molars' root canals showed inherent limitations in terms of voids and quality of filling. Voids are inevitable and were present in all the techniques. Overfilling was more frequently seen with the syringe method, while the lentulo spiral technique, both handheld and rotary, showed a better quality of filling.