Delivery of Calcium Hydroxide: Comparison of Four Filling Techniques

This study compared the weight and radiographic appearance of Ca(OH) 2 delivered into standardized, minimally and fully prepared canals using (a) an injection system, (b) an endodontic Flex-O file rotated counter-clockwise, (c) a lentulo spiral, and (d) a .04 rotary NiTi file rotated in reverse. Two extracted human second mandibular premolars with single canals were prepared to an MAF #25 or an MAF #40. A weight measurement and radiograph were made for each filling. Three independent examiners evaluated the radiographs. Regardless of technique, only about 45% of the optimal weight of Ca(OH) 2 was delivered into the minimally prepared canal. Radiographically the filling quality was only 1 to 2 (10 scale). In contrast, all delivery techniques delivered near optimal weight of Ca(OH) 2 in the completely prepared canal with a radiographic filling quality of 8.8 to 9.3. The results indicate that complete instrumentation is needed to obtain near optimal delivery of Ca(OH) 2.