Marginal seal and biocompatibility of a fourth-generation bonding agent.
OBJECTIVE
The pulpal reaction and the marginal sealing of in vivo restored samples using resin composite and Scotchbond Multi-Purpose adhesive system (3M Dental Products) were analyzed in this study.


METHODS
Twelve Class I non-exposed cavity preparations were placed on premolars to be removed for orthodontic reasons. They were restored and observed at 7 d and 28 d.


RESULTS
The examination of the resin-dentin interface under the scanning electron microscope (SEM) revealed: 1) a gap-free attachment between adhesive resin and dentinal surface in 80% of the areas studied, 2) penetration of resin tags into the dentinal tubules, and 3) formation of a 3-5 micrometer thick acid-resistant hybrid layer. Microfissures measuring about 10 micrometers were observed in only 20a% of the areas studied; these were located along the walls of the cavities, especially near the enamel in zones where there was a lower concentration of dentinal tubules. The histological analysis, carried out 7 d after preparation of the restoration, did not show any alteration of the pulp. After 4 wk, reparative dentin was produced in the pulpal areas corresponding to the restored cavities.


CONCLUSIONS
The quantity of newly formed dentin is correlated with the distance from the cavity to the pulp. The results indicate that acid-etching of vital dentin using 10% maleic acid does not impair pulpal healing in deep Class I cavities and that the Scotchbond Multi-Purpose adhesive system is able to preserve the morphological and biological integrity of the pulpo-dentinal complex.
Goracci
G
G
Department of Operative Dentistry, University "La Sapienza", Rome, Italy.
Mori
G
G
Bazzucchi
M
M
D000134:Acid Etching, Dental; D000328:Adult; D001672:Biocompatible Materials; D003188:Composite Resins; D018772:Dental Marginal Adaptation; D003782:Dental Pulp / Q000187:drug effects*; D003804:Dentin / Q000648:ultrastructure; D003806:Dentin Permeability; D003809:Dentin, Secondary / Q000254:growth & development; D017220:Dentin-Bonding Agents / Q000494:pharmacology; D006801:Humans; D008298:Maleates / Q000494:pharmacology; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D012822:Silicon Dioxide / Q000494:pharmacology; D013499:Surface Properties; D015040:Zirconium / Q000494:pharmacology
D001672:Biocompatible Materials; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D008298:Maleates; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; C083568:Z100 composite resin; D012822:Silicon Dioxide; C030272:maleic acid; D015040:Zirconium