endodontically treated teeth restored with post and core face failure due to loosening of the post , fracture of the post or the root itself.1 the common post and core complications documented were post loosening ( 5% ) , root fracture ( 3% ) , caries ( 2% ) , and periodontal disease ( 2%).2 fracture of the coronal tooth structure can occur on anterior teeth as they are subjected to shear stresses . very often the post and core fails , leaving behind an intact crown .
root may have adequate bone support and which could be favorably used if the post is retrieved .
this clinical report describes the technique of refabricating post and core to match the features of the existing crown .

 a 34-year - old female patient reported with fractured maxillary right canine tooth ( figure 1 ) . on examination , it was found that the tooth was the root canal treated and restored with a cast post and core and a metal ceramic crown over it ( figure 2 ) .
the core was fractured leaving the cast post embedded in the root.the post was loosened using ultrasonic vibrations and retrieved using an artery forceps .
the residual cement in the post space was removed and a fiber post of diameter 1.5 mm ( flexi - post , coltenewhaledent ) was bonded using dual - cured composite resin ( paracore , coltenewhaledent ) ( figure 3).the crown was intact , and it was decided to use the same for restoring the fractured tooth . a 50 m polytetrafluoroethylene ( ptfe ) ( teflon )
tape was adapted on the tissue surface of the crown and a dual - cured core build - up composite resin ( paracore , coltenewhaledent ) was injected into the crown and positioned over the bonded post ( figures 4 - 6 ) .. it was then light polymerized for 40 s.the crown was then removed leaving the core bonded to the post and the tooth structure .
the core was light polymerized again for 40 s. the teflon tape was removed from the crown , and the crown was cemented to the core using glass ionomer cement ( gic gold label glass ionomer luting and lining cement ) ( figure 7 ) .. the patient was followed up for 1 year , and it was uneventful . 
 
a 34-year - old female patient reported with fractured maxillary right canine tooth ( figure 1 ) . on examination
, it was found that the tooth was the root canal treated and restored with a cast post and core and a metal ceramic crown over it ( figure 2 ) .
the residual cement in the post space was removed and a fiber post of diameter 1.5 mm ( flexi - post , coltenewhaledent ) was bonded using dual - cured composite resin ( paracore , coltenewhaledent ) ( figure 3 ) .
the crown was intact , and it was decided to use the same for restoring the fractured tooth . a 50 m polytetrafluoroethylene ( ptfe ) ( teflon ) tape was adapted on the tissue surface of the crown and a dual - cured core build - up composite resin ( paracore , coltenewhaledent ) was injected into the crown and positioned over the bonded post ( figures 4 - 6 ) .. it was then light polymerized for 40 s. the crown was then removed leaving the core bonded to the post and the tooth structure .
the core was light polymerized again for 40 s. the teflon tape was removed from the crown , and the crown was cemented to the core using glass ionomer cement ( gic gold label glass ionomer luting and lining cement ) ( figure 7 ) .. the patient was followed up for 1 year , and it was uneventful .
the need for retreatment of a tooth and/or prosthetic restoration may arise due to secondary caries , pulpal involvement , trauma to the restoration , and/or foundation , and subjective desires for a more aesthetic or durable restoration . crowned teeth requiring retreatment due to fracture of the underlying tooth structure and/or foundation restoration
often possess an undamaged extracoronal restoration . in such cases , it may be desirable to reuse the restoration for the sake of cost and time.3 a badly distorted endodontically treated tooth is always a challenge for any dentist .
presented a comprehensive literature review over this topic and described his own way to handle these emergencies .
he inserted a prefabricated plastic post into the palatal canal of a maxillary molar . later on following an impression of the remaining tooth , already prepared for a crown
was inserted into a fresh fabricated crown , followed by crown cementation.4 an indirect fabrication of two separate castings , first for the post and then fabricating the core for mandibular molars was suggested by sadan et al .
this technique was similar to chiche s technique but worked on indirect fabrication method.5 cast post core systems accumulated stress within cast post cores and apical one - third region of the tooth . using fiber posts ,
the stresses were distributed to the cervical one - third region of the tooth and the supporting bone .
specimens restored with fiber - reinforced post systems offered more homogenous stress distribution than cast posts as fiber posts possess a similar modulus of elasticity to that of dentin.6,7 hence , it was decided to use a glass fiber post for this case .
the use of ptfe tape provides a space of approximately 50 m , which was used to accommodate the cement.8
in this paper , the most common difficulty in the clinical practice has been discussed .
restoration for the endodontically treated teeth , where there is hardly no proper support for the post makes the work for the clinicians more complicated and challenging .
this paper describes a novel technique for refabricating a post and core restoration for an existing crown using polyfluoroethylene tape .
 a fractured coronal tooth structure beneath an intact crown is a common clinical occurrence . 
 if the underlying root is healthy , the tooth is restored with a post and core followed by refabrication of the crown . 
 this paper describes a technique of using the existing intact crown for the above - mentioned situation . 
 a 34-year - old female was referred with a fractured right canine with an intact crown . 
 a post was found fractured in the canal which was subsequently retrieved . 
 a new fiber post was cemented in the post space followed by adaptation of 50 m polytetrafluoroethylene ( teflon ) tape on the tissue surface of the crown . 
 dual - cured core build - up composite resin was injected into the crown and adapted to the fractured tooth . on curing and removal of the crown , 
 a new composite resin core was found bonded to the tooth structure . 
 the teflon tape was removed from the crown , and the crown cemented to the core using glass ionomer cement . 
 this technique of building up the core of the tooth using teflon tape adapted to the tissue surface of the crown was found to be successful even after 1 year of follow - up . 
Introduction
Technique
Discussion
Conclusion