Ultra-morphology of self-etching adhesives on ground enamel: a high resolution SEM study.
OBJECTIVE
To evaluate the effect of different commercial self-etching agents on enamel morphology using high-resolution in-lens scanning electron microscopy (FEISEM).


METHODS
The bonding systems selected for the study were: Prime & Bond NT (no-etch technique), Prime & Bond 2.1 (no-etch technique), NRC/Prime and Bond NT, Syntac Single Component, Prompt L-Pop, F2000, and Clearfil SE Bond. The positive control group was prepared with Single Bond upon etching enamel with the proprietary 35% phosphoric acid gel. 24 extracted human molars were equally and randomly assigned to the experimental and control groups. All bonding materials were applied on enamel following the manufacturers' instructions. A thin layer of composite was applied on the polymerized adhesive agent, after which the enamel was dissolved to obtain replicas that were observed under a FEISEM.


RESULTS
Observations revealed different morphological features brought about by the adhesive systems. A relationship between the morphological appearance and the pH of the adhesive solutions was found. Three different groups of self etching were identified: Group 1 showed no or little evidence of modifications on the enamel surface (Prime & Bond NT and Prime & Bond 2.1, no-etch technique), Group 2 revealed major aggressive properties that were able to disclose the prism morphology (Syntac Single Component, F2000, Clearfil SE Bond), and Group 3 (NRC/Prime & Bond NT and Prompt L-Pop) revealed morphological features similar to those obtained with Single Bond after etching with phosphoric acid (control group).
Breschi
Lorenzo
L
Clinica Odontostomatologica, Department of Surgical Sciences, University of Trieste, Via Stuparich, 1, 34129, Trieste, Italy. lbreschi@units.it
Gobbi
Pietro
P
Falconi
Mirella
M
Mazzotti
Giovanni
G
Prati
Carlo
C
Perdigão
Jorge
J
D000096:Acetone / Q000737:chemistry; D000134:Acid Etching, Dental; D020770:Compomers / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure*; D045662:Dental Etching; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008298:Maleates / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties
C112828:Clearfil AP-X; C438313:Clearfil SE Bond; D020770:Compomers; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C118368:F2000 cement; C444701:Filtek Z250; D005899:Glass Ionomer Cements; D008298:Maleates; D008689:Methacrylates; D010756:Phosphoric Acids; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; C408584:Prompt L-Pop; D019279:Resin Cements; C078484:Syntac dentine adhesive; C444699:non-rinse conditioner; C444444:prime and bond 2.1; D000096:Acetone