title: An ex-vivo comparative study of root-end marginal adaptation using grey mineral trioxide aggregate, white mineral trioxide aggregate, and Portland cement under scanning electron microscopy.
abstract: BACKGROUND
  Where nonsurgical endodontic intervention is not possible, or it will not solve the problem, surgical endodontic treatment must be considered. A major cause of surgical endodontic failures is an inadequate apical seal, so the use of the suitable substance as root-end filling material that prevents egress of potential contaminants into periapical tissue is very critical.
  
  
  OBJECTIVE
  The aim of the present ex-vivo study was to compare and evaluate the three root-end filling materials of mineral trioxide aggregate (MTA) family (white MTA [WMTA], grey MTA [GMTA] and Portland cement [PC]) for their marginal adaptation at the root-end dentinal wall using scanning electron microscopy (SEM).
  
  
  METHODS
  Sixty human single-rooted teeth were decoronated, instrumented, and obturated with Gutta-percha. After the root-end resection and apical cavity preparation, the teeth were randomly divided into three-experimental groups (each containing 20 teeth) and each group was filled with their respective experimental materials. After longitudinal sectioning of root, SEM examination was done to determine the overall gap between retrograde materials and cavity walls in terms of length and width of the gap (maximum) at the interface. Descriptive statistical analysis was performed to calculate the means with corresponding standard errors, median and ranges along with an analysis of variance and Tukey's test.
  
  
  RESULTS
  The least overall gap was observed in GMTA followed by PC and WMTA. While after statistically analyzing the various data obtained from different groups, there was no significant difference among these three groups in terms of marginal adaptation.
  
  
  CONCLUSIONS
  GMTA showed the best overall adaptation to root dentinal wall compared to PC and WMTA. Being biocompatible and cheaper, the PC may be an alternative but not a substitute for MTA.
authors.affiliation: Department of Conservative Dentistry and Endodontics, Faculty of Dental Sciences, IMS, BHU, Varanasi, Uttar Pradesh, India.
authors.forename: Akash Kumar
authors.initials: AK
authors.lastname: Baranwal
authors.affiliation: Department of Conservative Dentistry and Endodontics, Dr. R. Ahmed Dental College and Hospital, Kolkata, West Bengal, India.
authors.forename: Mohan L
authors.initials: ML
authors.lastname: Paul
authors.affiliation: Department of Dental, Calcutta Medical College, Kolkata, West Bengal, India.
authors.forename: Dibyendu
authors.initials: D
authors.lastname: Mazumdar
authors.affiliation: Department of Conservative Dentistry and Endodontics, Dr. R. Ahmed Dental College and Hospital, Kolkata, West Bengal, India.
authors.forename: Haridas Das
authors.initials: HD
authors.lastname: Adhikari
authors.affiliation: Department of Conservative Dentistry and Endodontics, Singhad Dental College, Pune, Maharashtra, India.
authors.forename: Nishant K
authors.initials: NK
authors.lastname: Vyavahare
authors.affiliation: Department of Conservative Dentistry and Endodontics, Melaka-Manipal Medical College, Melaka, Malaysia.
authors.forename: Kapil
authors.initials: K
authors.lastname: Jhajharia
keywords: Grey mineral trioxide aggregate; marginal adaptation; Portland cement; root-end filling materials; white mineral trioxide aggregate