title: Clinical evaluation of an oval-shaped prefabricated glass fiber post in endodontically treated premolars presenting an oval root canal cross-section: a retrospective cohort study.
abstract: OBJECTIVE
  This retrospective cohort study investigated the clinical effectiveness of preformed oval-shaped glass fiber posts in combination with a dual-curing composite resin core material in endodontically treated premolars presenting an oval root canal cross-section and restored with all-ceramic crowns over up to 45 months.
  
  
  METHODS
  The study population comprised 134 patients and 154 endodontically treated premolars, with varying degrees of hard tissue loss, restored by means of oval-shaped fiber-reinforced posts. Inclusion criteria were premolars presenting an oval-shaped root canal, symptom-free endodontic therapy, root canal treatment with a minimum apical seal of 4 mm, application of rubber dam, and the need for a post and core complex because of coronal tooth loss. Four groups were defined based on the number of preserved coronal walls after endodontic treatment and before core buildup. Survival rate of the post and core restorations was determined using Kaplan-Meier analysis, and statistical analysis was performed using the log-rank test (P < .05).
  
  
  RESULTS
  The posts and cores were examined clinically and radiographically. The mean observation period was 42.3 ± 2.7 months. The overall survival rate was 95.45%. Comparisons revealed that the difference between premolars with no coronal wall retention and premolars that had maintained one to four coronal walls was statistically significant (P = .0006). On the contrary, comparison between premolars with one and two residual walls was found to be not significant for the overall survival rate (P = .0698).
  
  
  CONCLUSIONS
  A satisfactory clinical performance was observed for preformed oval-shaped glass fiber posts. Survival was higher for teeth retaining three and four coronal walls.
authors.affiliation: Department of Biophysics, Medicine and Dentistry, University of Genoa, Italy. dr.signore@tiscali.it
authors.forename: Antonio
authors.initials: A
authors.lastname: Signore
authors.forename: Vassilios
authors.initials: V
authors.lastname: Kaitsas
authors.forename: Giambattista
authors.initials: G
authors.lastname: Ravera
authors.forename: Francesca
authors.initials: F
authors.lastname: Angiero
authors.forename: Stefano
authors.initials: S
authors.lastname: Benedicenti
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001641:Bicuspid / Q000000981:diagnostic imaging; D015331:Cohort Studies; D003442:Crowns; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention / Q000295:instrumentation*; D003786:Dental Pulp Cavity / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery; D003793:Dental Restoration, Permanent / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011176:Post and Core Technique / Q000295:instrumentation*; D011859:Radiography; D012189:Retrospective Studies; D012390:Root Canal Therapy / Q000295:instrumentation*; D016896:Treatment Outcome; D055815:Young Adult