title: Experimental evaluation of two methodologies for the restoration of crown fracture in permanent anterior  teeth.
abstract: OBJECTIVE
  The purpose of this study is to compare, by means of mechanical tests, the resistance of two  types of dental  restoration in the uncomplicated crown fracture of human permanent maxillary central incisor: rebonding of the fractured  tooth fragment and application of ceramic veneers.
  
  
  METHODS
  Thirty human maxillary central incisors  were divided into three groups of ten teeth each. The teeth of the first group (Group A) were kept intact and used as controls,  while the remaining teeth were sectioned, in order to simulate a crown fracture, and restored respectively with either the  rebonding of the fragment (Group B) or with the use of ceramic veneers (Group C). All samples underwent mechanical tests  by means of a universal test machine.
  
  
  RESULTS
  The mean resistance to fracture recorded is respectively 425.2N for Group A,  233.3N for Group B, and 347.3N for Group C. One-way ANOVA analysis demonstrates statistical significance for at least one  couple of values (Group B compared to Group A). The group of restorations with rebonding of fractured fragments has a  mean value of resistance to fracture that is lower than both intact teeth and teeth restored with ceramic veneers. The  resistance of teeth with rebonded restorations is 54.9% of that of, intact teeth, and resistance increases for teeth  restored with ceramic veneers (81.8% of that of intact teeth).
  
  
  CONCLUSIONS
  Ceramic veneers showed a higher  resistance than rebonding and resulted to be more reliable in case of further trauma.
authors: Department of Clinical Dentistry, School of Dentistry, University of Padova, Padova, Italy.
authors: E
authors: E
authors: Stellini
authors: M
authors: M
authors: De Francesco
authors: S
authors: S
authors: Sivolella
authors: R
authors: R
authors: Ferro
authors: G
authors: G
authors: Denotti
authors: D
authors: D
authors: Oberholtzer
authors: S
authors: S
authors: Mazzoleni
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding / Q000379:methods; D003743:Dental Enamel / Q000293:injuries / Q000648:ultrastructure; D003764:Dental Materials / Q000737:chemistry; D003776:Dental Porcelain / Q000737:chemistry; D003793:Dental Restoration, Permanent / Q000379:methods*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003801:Dental Veneers; D003804:Dentin / Q000648:ultrastructure; D006801:Humans; D007180:Incisor / Q000293:injuries*; D008422:Materials Testing; D063065:Organophosphonates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013314:Stress, Mechanical; D019228:Tooth Crown / Q000293:injuries*; D014082:Tooth Fractures / Q000628:therapy*; D019246:Tooth Preparation / Q000379:methods
chemical_list: D003188:Composite Resins; D003764:Dental Materials; C444701:Filtek Z250; D063065:Organophosphonates; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; C454540:Scotchbond etchant; D003776:Dental Porcelain