fa Time-based lateral hygroscopic expansion of a water-expandable endodontic obturation point اندودانتیکس Endodontics پژوهشي Research <p> <strong>Objectives</strong></p><p>  This study compared the time-based lateral expansion of two sizes and two batches of water-expandable obturation points (CPoint, EndoTechnologies, LLC) and a similar-sized gutta-percha point (control) at various distances from the point apex: 5, 10, and 15mm.</p><p> <strong> Methods</strong></p><p>  Two batches of sizes 25 and 40 (0.06 taper) CPoints and a single lot of size 40 (0.06 taper) gutta-percha were tested (N=5). Points were fixed to the bottom of a Petri dish, and digital images of each point location were obtained under 50× magnification, which also captured a calibrated linear scale reticule. After imaging each dry cone location, 10mL of water was added, and images were obtained at various time points: 20 and 40min, 1, 2, 3, 4, 5, 6, 7, 8, and 24h. Between measurements, dishes were stored at 37°C. Side-to-side dimension of each point was determined using imaging software </p><p> <strong>Results</strong> </p><p> No significant differences (p>0.05) in lateral dimension at each tip distance between batches of similar-sized CPoint samples were found (2-tailed unpaired Student's t-test). Changes in CPoint dimension were significantly higher (p<0.05) for both sizes at each tip distance after 20min of water immersion (one-factor repeated-measures ANOVA Tukey test). Gutta-percha did not significantly change from the dry value during water immersion (p>0.05). </p><p> <strong>Conclusions</strong></p><p>  When exposed to water, the lateral expansion of a new hydrophilic endodontic obturation point significantly increases in dimension within 20min, whereas a conventional gutta-percha point does not. </p><hr><p></p><p> <strong>Source: </strong>Journal of Dentistry</p><p> <a href="http://www.jodjournal.com/article/S0300-5712(13)00161-9/abstract" target="_blank"><font color="#0000ff">Full Text</font></a></p> CPoint, Endodontics, Hygroscopic expansion, Lateral expansion, Obturation 0 0 http://idai.ir/browse.php?a_code=A-10-32-2193&slc_lang=fa&sid=1 Anthony Didato 100319475328460010311 100319475328460010311 No Department of Endodontics, Georgia Regents University, Augusta, GA, USA Ashraf A. Eid 100319475328460010312 100319475328460010312 No Department of Dental and Biomedical Material Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan Martin D. Levin 100319475328460010313 100319475328460010313 No Private Endodontic Practice, Chevy Chase, MD, USA Sara Khan 100319475328460010314 100319475328460010314 No Department of Endodontics, Georgia Regents University, Augusta, GA, USA Franklin R.Tay 100319475328460010315 100319475328460010315 Yes Department of Endodontics, Georgia Regents University, Augusta, GA, USA Frederick A. Rueggeberg 100319475328460010316 100319475328460010316 No Department of Oral Rehabilitation, Georgia Regents University, Augusta, GA, USA