Background: An essential step in the effectiveness of root canal therapy is root canal obturation. Although gutta percha is the most widely utilized root canal filler material, its inability to stick to dentinal canal walls prevents it from completely sealing the root canal gap. The present study to compared the percentage of voids in root canal obturation using different techniques of sealer placement. Materials & Methods: 70 mandibular first premolars were divided into two groups of 35 each. The K file was employed in group I, while the Lentulo spiral sealer placement technique was used in group II. Sections were examined for void detection in the apical, middle, and coronal thirds using a digital microscope set to 150X magnification. Results: In group I, K file and in group II, Lentulo spiral sealer placement technique was used. Percentage of voids at coronal sections was3% and 2%, at middle third was 2% and 1% and at apical third was 1% and 0% in group I and II respectively. The difference was significant (P< 0.05). Conclusion: The K file method of sealer installation produced the highest percentage of voids.