Abstract
Effects of spreader penetration depth on the quality of apical seal
 Dr. M. Alaeddini* - Dr. M. Parirokh**
 * - Oral and Maxillofacial pathologist – Dental Research Centre – Tehran University of Medical Sciences.
**- Associate professor of Endodontics Dept. – Faculty of Dentistry – Kerman University of Medical Sciences.
 Background and Aim: A proper root canal filling is accomplished by complete obturation of the root canal with an inert filling material. Therefore, the creation of an apical seal has been proposed as goals for a successful endodontic treatment. The aim of this study was to deter-mine the effects of spreader penetration depth on apical seal.
Materials and Methods: Thirty – three canals were instrumented by step – back technique. In 12 canals, finger (F) spreader penetrated at 0.5 mm of the prepared length (group 1). In another 9 canals, F spreader penetrated at 1 mm of the prepared length (group 2). After 24 hours, in 100% humidity, the roots, except for the 3 mm of apical part, were covered by nail polish. Six canals were not obturated as positive group and other six ones were completely covered by nail polish (negative controls). All roots were suspended in dye for 72 hours. The teeth were then cut longitudinally and apical leakage was measured and recorded. Data were subjected to t – test and Mann – whitney U test.
Results: The mean dye penetration and standard deviation, in group 1, were 0.4492 and 0.209, respectively whereas those of group 2 were 1.2767 and 0.916, respectively. It was shown that average dye penetration in groups 1 was significantly less than that of group 2 (P<0.05).
Conclusion: Considering the importance of a proper apical seal in a successful endodontic treatment, more spreader penetration depth in lateral condensation technique is recommended.
Key words: Lateral condensation – Microleakage – Spreader