title: Influence of Warm Vertical Compaction Technique on Physical Properties of Root Canal Sealers.
abstract: BACKGROUND
  The aim of this study was to evaluate the influence of warm vertical compaction on the physical properties of root canal sealers.
  
  
  METHODS
  The physical properties of 4 sealers (zinc oxide -eugenol [ZOE], AH Plus [Dentsply International, York, PA], RoekoSeal [Roeko/Coltene/Whaledent, Langenau, Germany], and iRoot SP [Innovative Bioceramix, Vancouver, Canada]) were tested. The setting time and flow of these sealers were measured at standard and high temperatures using ISO 6876 (2012) specifications. The percentage of voids in each sealer after complete setting at 37°C and 140°C was analyzed under a stereoscopic microscope.
  
  
  RESULTS
  The setting time of ZOE sealer increased significantly from 144.0 ± 4.1 minutes to 274.2 ± 7.4 minutes when the temperature increased from 37°C to 140°C, whereas there was a significant reduction in the other 3 sealers. At 37°C, the setting time of AH Plus, iRoot SP, and RoekoSeal was 543.8 ± 16.4, 245.8 ± 15.9, and 49.3 ± 1.5 minutes, and at 140°C the setting time decreased significantly to 12.9 ± 0.7, 14.2 ± 0.6, and 2.7 ± 0.4 minutes (P < .05). The flow of AH Plus increased when the temperature changed from 25°C to 140°C (P < .05), whereas the flow reduced for RoekoSeal and iRoot SP (for RoekoSeal from 24.8 ± 0.9 to 12.4 ± 1.3 mm and for iRoot SP from 22.9 ± 0.9 to 13.3 ± 1.5 mm) (P < .05). However, the flow of ZOE sealer was unaffected by the high temperature. ZOE sealer and iRoot SP exhibited a reduction of porosity at a high temperature (P < .05).
  
  
  CONCLUSIONS
  Warm vertical compaction influenced some properties (the setting time, flow, and porosity) of 4 sealers. A significant reduction of setting time and flow was found in RoekoSeal and iRoot SP sealers at a high temperature.
authors: Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing, China.
authors: Wei
authors: W
authors: Qu
authors: Dental Material Laboratory, Peking University School and Hospital of Stomatology, Beijing, China.
authors: Wei
authors: W
authors: Bai
authors: Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing, China; Dental Clinic, Peking University International Hospital, Beijing, China. Electronic address: leungyuhong@sina.com.
authors: Yu-Hong
authors: YH
authors: Liang
authors: Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing, China.
authors: Xue-Jun
authors: XJ
authors: Gao
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry; D003786:Dental Pulp Cavity; D006171:Gutta-Percha / Q000737:chemistry; D006358:Hot Temperature; D008422:Materials Testing; D055585:Physical Phenomena; D016062:Porosity; D012387:Root Canal Filling Materials / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D014783:Viscosity; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D012387:Root Canal Filling Materials; D017640:Silicates; D015035:Zinc Oxide-Eugenol Cement; C112894:canals sealer; C506393:tricalcium silicate; D006171:Gutta-Percha
keywords: Physical properties; root canal sealers; warm vertical compaction