title: Influence of coronal restorations on the fracture resistance of root canal-treated premolar and molar teeth: a retrospective study.
abstract: To evaluate the influence of coronal restorations on the fracture resistance of endodontically treated teeth, 676 root canal-filled and restored posterior teeth were evaluated after a mean period of 9.7 (± 2.8; minimum: 5) years. A total of 86.2% of the endodontically treated and restored teeth survived the mean observation period of 9.7 years without fracture. The overall survival period was 13.6 (± 0.2) years. All teeth with gold partial crowns survived without fractures (n = 24). Teeth with crowns and adhesively sealed access cavities showed a mean survival period of 15.3 (± 0.4) years, with crown and bridge restorations 14.0 (± 0.3), with individual metal posts 13.9 (± 0.2), with composite fillings 13.4 (± 0.5), with prefabricated metal posts 12.7 (± 0.6), with amalgam fillings 11.8 (± 0.6) and with glass ionomer cements (GIC) 6.6 (± 0.5) years. Teeth with one or two surfaces restored by amalgam, composite or GIC showed a significantly lower fracture rate than teeth with three and more restored surfaces (P < 0.05). The mean fracture rate of teeth restored with GIC was significantly higher when compared with all other groups (P < 0.001). In general, endodontically treated teeth restored with prosthetic restorations demonstrated a significantly lower mean fracture rate than teeth restored with fillings. Cavities with up to three surfaces may well be successfully restored adhesively with composite filling material.
authors.affiliation: Department of Operative Dentistry, Westphalian Wilhelms-University, Münster, Germany. tillda@uni-muenster.de
authors.forename: Till
authors.initials: T
authors.lastname: Dammaschke
authors.forename: Kathrin
authors.initials: K
authors.lastname: Nykiel
authors.forename: Darius
authors.initials: D
authors.lastname: Sagheri
authors.forename: Edgar
authors.initials: E
authors.lastname: Schäfer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001641:Bicuspid / Q000503:physiopathology*; D003188:Composite Resins / Q000737:chemistry; D003442:Crowns / Q000145:classification; D003722:Dental Alloys / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry; D003793:Dental Restoration, Permanent / Q000379:methods*; D003829:Denture, Partial; D005260:Female; D005500:Follow-Up Studies; D005899:Glass Ionomer Cements / Q000737:chemistry; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D008297:Male; D008875:Middle Aged; D008963:Molar / Q000503:physiopathology*; D011176:Post and Core Technique / Q000295:instrumentation; D012189:Retrospective Studies; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D016019:Survival Analysis; D014082:Tooth Fractures / Q000503:physiopathology*; D019553:Tooth, Nonvital / Q000628:therapy*; D055815:Young Adult
chemical_list: D003188:Composite Resins; D003722:Dental Alloys; D003764:Dental Materials; D005899:Glass Ionomer Cements; D006047:Gold Alloys; D012387:Root Canal Filling Materials; D003723:Dental Amalgam
keywords: coronal restoration; fracture resistance; post-endodontic restoration; root canal treatment; survival rate