title: The survival of indirect composite resin onlays for the restoration of root filled teeth: a retrospective medium-term study.
abstract: OBJECTIVE
  To investigate the outcomes of root filled posterior teeth restored with indirect composite resin onlays using tooth and restoration survival as well as the quality of restoration as outcome measures.
  
  
  METHODS
  All patients were treated by the same clinician with indirect composite onlays for the restoration of root filled posterior teeth between January 2008 and February 2010 in a single clinic setting. Primary root canal treatment was performed and onlays fabricated with the indirect method using indirect composite resin. Patients were seen every 4-6 months for maintenance visits according to standard clinic protocols and each patient's individualized maintenance schedule. Tooth and restoration survival were calculated, and the onlays were evaluated in accordance with the modified US Public Health Service (USPHS) criteria.
  
  
  RESULTS
  Thirty-one premolars and one hundred and fifty-eight molars (n = 189) of 153 patients were included. The observation period ranged from 24 to 52 months with a median follow-up time of 37 months. Tooth survival was found to be 100%, whilst the restoration survival was 96.8% and the functional restoration survival 98.9% at the end of the follow-up period. According to modified USPHS criteria, the A rating had a range of 83.1-100% for all evaluation criteria.
  
  
  CONCLUSIONS
  Onlay restorations fabricated with indirect resin can be a viable option for the restoration of root filled teeth.
authors.affiliation: Advanced Education Program in Endodontics, UTHSCSA, San Antonio, TX, USA.
authors.forename: V
authors.initials: V
authors.lastname: Chrepa
authors.forename: I
authors.initials: I
authors.lastname: Konstantinidis
authors.forename: G A
authors.initials: GA
authors.lastname: Kotsakis
authors.forename: M E
authors.initials: ME
authors.lastname: Mitsias
mesh_terms: D000328:Adult; D000368:Aged; D003188:Composite Resins; D003793:Dental Restoration, Permanent; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012390:Root Canal Therapy
chemical_list: D003188:Composite Resins
keywords: composite resin onlays; endodontic therapy; endodontically treated teeth; onlay restoration; survival rate