title: Effect of calcium hydroxide on the apical leakage of Resilon-filled root canals: An in vitro study.
abstract: Calcium hydroxide is used as an intracanal medication for root canal disinfection and to enhance periapical lesion healing. However, calcium hydroxide remnants can negatively affect the final apical seal of obturated canals. The current study investigated apical leakage in root canals filled with Resilon after calcium hydroxide treatment.  Seventy human maxillary central incisors were instrumented to a master apical file size of 40. Teeth were randomly divided into two experimental groups (A and B; n = 30) and two control groups (n = 5). Root canals in group A received a calcium hydroxide dressing, while those in group B received no intracanal medication. One week after treatment, all root canals were obturated with Resilon/Epiphany using lateral compaction. Groups A and B were randomly divided into subgroups A1, A2, B1, and B2 (n = 15). All subgroups were stored in an incubator at 37 degrees C and 100% humidity; subgroups A1 and B1 were stored for one week, while subgroups A2 and B2 were stored for eight weeks. Dye penetration and clearing techniques were used to evaluate apical leakage. Data were analyzed using a Student t-test, with significance set at P < 0.05.  Observed apical leakage was significantly higher in subgroup A1 than in subgroups A2 and B1 and in subgroup A2 than in subgroup B2; no statistically significant difference was found between subgroups B1 and B2.  When used as an intracanal medication, calcium hydroxide increases the apical leakage of root canals filled with Resilon/Epiphany.
authors.affiliation: Department of Endodontics, Qazvin University of Medical Sciences, Qazvin, Iran.
authors.forename: Mamak
authors.initials: M
authors.lastname: Adel
authors.forename: Maryam
authors.initials: M
authors.lastname: Foroozia
authors.forename: Mohammed-Hossein
authors.initials: MH
authors.lastname: Rezaei
authors.forename: Nima
authors.initials: N
authors.lastname: Mahboobi
mesh_terms: D002126:Calcium Hydroxide / Q000737:chemistry / Q000627:therapeutic use*; D002244:Carbon; D004396:Coloring Agents; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification*; D004492:Edetic Acid / Q000627:therapeutic use; D006801:Humans; D006813:Humidity; D007180:Incisor / Q000473:pathology; D008422:Materials Testing; D008751:Methylene Blue; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000737:chemistry / Q000627:therapeutic use*; D012389:Root Canal Obturation / Q000379:methods; D018915:Root Canal Preparation / Q000295:instrumentation; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013696:Temperature; D013997:Time Factors; D019227:Tooth Apex / Q000473:pathology*
chemical_list: D004396:Coloring Agents; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C028433:chinese ink; C486893:epiphany sealer; C486892:resilon sealer; D002244:Carbon; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D002126:Calcium Hydroxide; D008751:Methylene Blue