title: An In Vitro Study on the Effects of Post-Core Design and Ferrule on the Fracture Resistance of Endodontically Treated Maxillary Central Incisors.
abstract: BACKGROUND
  Endodontically treated teeth have significantly different physical and mechanical properties compared to vital teeth and are more prone to fracture. The study aims to compare the fracture resistance of endodontically treated teeth with and without post reinforcement, custom cast post-core and prefabricated post with glass ionomer core and to evaluate the ferrule effect on endodontically treated teeth restored with custom cast post-core.
  
  
  METHODS
  A total of 40 human maxillary central incisors with similar dimensions devoid of any root caries, restorations, previous endodontic treatment or cracks were selected from a collection of stored extracted teeth. An initial silicone index of each tooth was made. They were treated endodontically and divided into four groups of ten specimens each. Their apical seal was maintained with 4 mm of gutta-percha. Root canal preparation was done and then post core fabrication was done. The prepared specimens were subjected to load testing using a computer coordinated UTM. The fracture load results were then statistically analyzed. One-way ANOVA was followed by paired t-test.
  
  
  RESULTS
  1. Reinforcement of endodontically treated maxillary central incisors with post and core, improved their fracture resistance to be at par with that of endodontically treated maxillary central incisor, with natural crown. 2. The fracture resistance of endodontically treated maxillary central incisors is significantly increased when restored with custom cast post-core and 2 mm ferrule.
  
  
  CONCLUSIONS
  With 2 mm ferrule, teeth restored with custom cast post-core had a significantly higher fracture resistance than teeth restored with custom cast post-core or prefabricated post and glass ionomer core without ferrule.
authors.affiliation: Professor, Department of Prosthodontics, Century International Institute of Dental Sciences and Research Centre, Poinachi, Thekkil, Kasaragode, Kerala, India.
authors.forename: S
authors.initials: S
authors.lastname: Sreedevi
authors.affiliation: Professor, Department of Periodontics, Indira Gandhi Institute of Dental Sciences, Nellikuzhi, Kothamangalam, Kerala, India.
authors.forename: R
authors.initials: R
authors.lastname: Sanjeev
authors.affiliation: Professor, Department of Periodontics, Educare Institute of Dental Sciences, Malappuram, Kerala, India.
authors.forename: Rekha
authors.initials: R
authors.lastname: Raghavan
authors.affiliation: Reader, Department of Periodontics, Educare Institute of Dental Sciences, Malappuram, Kerala, India.
authors.forename: Anna
authors.initials: A
authors.lastname: Abraham
authors.affiliation: Professor, Department of Pedodontics and Preventive Dentistry, Mahe Institute of Dental Sciences & Hospital, Chalakkara, Mahe, Puducherry, India.
authors.forename: T
authors.initials: T
authors.lastname: Rajamani
authors.affiliation: Professor, Department of Oral and Maxillofacial Surgery, Mahe Institute of Dental Sciences and Hospital, Chalakkara, Mahe, Puducherry, India.
authors.forename: Girish Kumar
authors.initials: GK
authors.lastname: Govind
keywords: cast-posts; endodontically treated teeth; ferrule; fracture resistance; prefabricated posts