title: [Bond strengths of absorbable polylactic acid root canal post with three different adhesives].
abstract: OBJECTIVE
  To find absorbable adhesives with suitable bonding properties for the absorbable polylactic acid root canal post. To test and compare the bond strengths of absorbable polylactic acid root canal post with three different adhesives.
  
  
  METHODS
  The absorbable polylactic acid root canal posts were used to restore the extracted teeth, using 3 different adhesives: cyanoacrylates, fibrin sealant and glass ionomer cement. The teeth were prepared into slices for micro-push-out test. The bond strength was statistically analyzed using ANOVA. The specimens were examined using microscope and the failure mode was divided into four categories: cohesive failure between absorbable polylactic acid root canal posts and adhesives, cohesive failure between dentin and adhesives, failure within the adhesives and failure within the absorbable polylactic acid root canal posts.
  
  
  RESULTS
  The bond strength of cyanoacrylates [(16.83 ± 6.97) MPa] and glass ionomer cement [(12.10 ± 5.09) MPa] were significantly higher than fibrin sealant [(1.17 ± 0.50) MPa], P<0.001. There was no significant difference between cyanoacrylates and glass ionomer cement (P=0.156). In the group of cyanoacrylates, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 25.0%, the cohesive failure between the dentin and the adhesives was 16.7%, the failure within the adhesives was 33.3%, and the failure within the absorbable polylactic acid root canal posts was 25.0%. In the group of fibrin sealant, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 66.7%, the cohesive failure between the dentin and the adhesives was 22.2%, the failure within the adhesives was 11.1%. In the group of glass ionomer cement, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 87.5%, the failure within the adhesives was 12.5%. The major failure mode in fibrin sealant and glass ionomer cement was the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives. No major failure modes were found in the group of cyanoacrylates.
  
  
  CONCLUSIONS
  The bond strength of fibrin sealant is low, which cannot meet the requirement of clinical use. The bond strengths of cyanoacrylates and glass ionomer cement are suitable for clinical use. The cyanoacrylates are a kind of absorbable adhesive which has suitable bonding properties for the absorbable polylactic acid root canal post.
authors.affiliation: Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China; Department of Stomatology, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Pan
authors.affiliation: Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Can
authors.initials: C
authors.lastname: Cheng
authors.affiliation: Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: He
authors.initials: H
authors.lastname: Liu
authors.affiliation: Dental Materials Research Laboratory, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Zhi-hui
authors.initials: ZH
authors.lastname: Sun
mesh_terms: D000269:Adhesives; D001840:Dental Bonding; D003786:Dental Pulp Cavity; D003804:Dentin; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D006801:Humans; D019344:Lactic Acid; D008422:Materials Testing; D011091:Polyesters; D011108:Polymers; D011176:Post and Core Technique; D012390:Root Canal Therapy
chemical_list: D000269:Adhesives; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)