Aim: This study evaluates the apical plug formation in 2 cases with necrotic immature maxillary central incisors in 11 & 12 yrs old female patients by the use of spinal tap needle to create apical plug in single increment without any residual MTA attachment to the   wall of the root canal.

Design: The shape of the immature root canal resembles a truncated cone. To achieve a truncated cone with MTA on the apical 4 mm in order to plug the open apex, the volume of material that will be required can be calculated by taking spinal tap needle equal to last file used, in a way that the MTA extruded is equal to the amount required to shape the apical plug in a single increment

Result: A uniform void free apical plug were made in single increment by using this technique.

Conclusion: This spinal tap needle is very economical, available in various sizes corresponding to endodontic K files, so spinal tap needle method is a viable method to create uniform void free accurate apical plug in one increment  without the wastage of material and time preventing the material to extrude beyond.

Keywords: Calcium hydroxide, Mineral trioxide aggregate, Pediatric dentistry