Short-term evaluation of the pulpo-dentin complex response to a resin-modified glass-ionomer cement and a bonding agent applied in deep cavities.
OBJECTIVE
To evaluate the response of the pulpo-dentin complex following application of a resin-modified glass-ionomer cement or an adhesive system in deep cavities performed in human teeth.


METHODS
Deep class V cavities were prepared on the buccal surface of 26 premolars. In Group 1 the cavity walls (dentin) and enamel were conditioned with 32% phosphoric acid and the dentin adhesive system One Step (Bisco, Inc., Itasca, IL, USA) was applied. In Groups 2 and 3, before total etching and application of bonding agent, the cavity floor was lined with the resin-modified glass-ionomer cement-Vitrebond (3M ESPE Dental Products Division, St. Paul, MN, USA) or the calcium hydroxide cement-Dycal (control group, Dentsply, Mildford, DE, USA), respectively. The cavities were restored using light-cured Z-100 composite resin (3M ESPE). The teeth were extracted between 5 and 30 days and prepared for microscopic assessment. Serial sections were stained with H/E, Masson's trichrome and Brown and Brenn techniques.


RESULTS
In Group 1, the inflammatory response was more evident than in Groups 2 and 3. Diffusion of dental material components across dentinal tubules was observed only in Group 1, in which the intensity of the pulp response increased as the remaining dentin thickness decreased. Bacteria were evidenced in the lateral walls of two samples (Group 2) which exhibited no inflammatory response or tissue disorganization.


CONCLUSIONS
Based on the experimental conditions, it was concluded total acid etching followed by application of One Step bonding agent cannot be recommended as adequate procedures. In this clinical condition the cavity walls should be lined with a biocompatible dental material, such as Vitrebond or Dycal.
D000134:Acid Etching, Dental; D000293:Adolescent; D000328:Adult; D001672:Biocompatible Materials / Q000737:chemistry; D002126:Calcium Hydroxide / Q000737:chemistry; D002648:Child; D003188:Composite Resins / Q000737:chemistry; D003736:Dental Cavity Lining; D003737:Dental Cavity Preparation / Q000145:classification*; D003782:Dental Pulp / Q000648:ultrastructure*; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D005500:Follow-Up Studies; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008689:Methacrylates / Q000737:chemistry; D008903:Minerals / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D012822:Silicon Dioxide; D015040:Zirconium
D001672:Biocompatible Materials; C103506:Bis-GMA, BPDM, HEMA dental-bonding resin; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D008689:Methacrylates; D008903:Minerals; D010756:Phosphoric Acids; D019279:Resin Cements; C083568:Z100 composite resin; C067790:Vitrabond; C025702:Dycal; D012822:Silicon Dioxide; D015040:Zirconium; D002126:Calcium Hydroxide