title: Evaluation of the Load-bearing Capacity of Fractured Incisal Edge of Maxillary Permanent Central Incisors restored with a Glass Fiber-reinforced Nanocomposite: An in vitro Study.
abstract: OBJECTIVE
  The aim of this study was to evaluate and compare the load-bearing capacity of fractured incisal edge of maxillary permanent central incisors restored with a nanocomposite and a glass fiber-reinforced nanocomposite.
  
  
  METHODS
  Thirty-six extracted sound maxillary central incisors randomly divided in three groups were used for the present study. Group I (control) contained untreated teeth. Samples in experimental groups II and III were prepared by cutting the incisal (one-third) part of the crown horizontally and subjected to enamel preparations and restored with a nanocomposite and a glass fiber-reinforced nanocomposite respectively. All restored teeth were stored in distilled water at room temperature for 24 hours. Fracture resistance was evaluated as peak load at failure (Newton) for samples tested in a cantilever-bending test using Hounsfield universal testing machine. Failure modes were microscopically examined.
  
  
  RESULTS
  Highest mean peak failure load (Newton) among experimental groups was observed in glass fiber-reinforced nano composite group (863.50 ± 76.12 N) followed by nanocomposite group (633.67 ± 40.14 N). One-way analysis of variance (ANOVA) revealed that the restoration technique significantly affected the load-bearing capacity (p < 0.001). Scheffe's post-hoc comparison test (subset for α = 0.05) revealed that there was significant difference in the mean peak failure load values of nanocomposite and glass fiber-reinforced nanocomposite groups when considered together (p < 0.001). Experimental groups showed similar types of failure modes with majority occurring ascohesive and mixed type. Fifty-eight percent of the teeth in glass fiber-reinforced nanocomposite group fractured below the cementoenamel junction.
  
  
  CONCLUSIONS
  By using fiber-reinforced composite substructure under conventional composites in the repair of fractured incisors, the load-bearing capacity of the restored incisal edge could be substantially increased. How to cite this article: Kumar PSP, Srilatha KT, Nandlal B, Dhull KS. Evaluation of the Load-bearing Capacity of Fractured Incisal Edge of Maxillary Permanent Central Incisors restored with a Glass Fiber-reinforced Nanocomposite: An in vitro Study. Int J Clin Pediatr Dent 2015;8(1):22-29.
authors.affiliation: Associate Professor, Department of Dentistry, Mysore Medical College and Research Institute, Mysore, Karnataka, India.
authors.forename: Ps Praveen
authors.initials: PP
authors.lastname: Kumar
authors.affiliation: Professor, Department of Pedodontics and Preventive Dentistry, JSS Dental College, JSS University, Mysore, Karnataka, India.
authors.forename: K T
authors.initials: KT
authors.lastname: Srilatha
authors.affiliation: Professor, Department of Pedodontics and Preventive Dentistry, JSS Dental College, JSS University, Mysore, Karnataka, India.
authors.forename: B
authors.initials: B
authors.lastname: Nandlal
authors.affiliation: Reader, Department of Pedodontics and Preventive Dentistry, Kalinga Institute of Dental Sciences, KIIT University, Bhubaneswar Odisha, India.
authors.forename: Kanika Singh
authors.initials: KS
authors.lastname: Dhull
keywords: Fracture resistance; Glass fiber-reinforced composite; Incisal edge fracture.; Nanocomposite; Self-etching adhesive