Noninvasive pit and fissure sealing: microtensile bond strength to intact bovine enamel of different pit and fissure sealants in a simplified fissure model.
OBJECTIVE
To measure the microtensile bond strength of different pit and fissure sealants in a simplified fissure model.


METHODS
Twenty extracted bovine mandibular permanent incisors were randomly divided into 4 groups for treatment: G1: 35% phosphoric acid/Clinpro Sealant; G2: 35% phosphoric acid/Delton; G3: Non-Rinse Conditioner/Dyract Seal; G4: 20% polyacrylic acid/Fuji IILC. Each tooth was sectioned into 6 pieces (4 x 6 mm) of buccal enamel. SEM examination was used to confirm the presence of aprismatic enamel on each tooth. Using a spacer, two pieces of etched enamel were secured to a glass slide at a mean distance of 0.6+/-0.1 mm. The space between enamel substrates was then etched/conditioned and sealed with different materials according to the tested groups. By serially cutting each double-bonded sample, multiple beam-shaped specimens about 0.8mm(2) in cross section were obtained and tested in tension (0.5 mm/min) until failure occurred at either one of the two stressed interfaces. Failure modes were classified by stereomicroscopy.


RESULTS
G1 and G2 showed statistically higher bond strengths than G3 and G4. G4 demonstrated the significantly lowest bond strength. Failures were mostly adhesive in G1, G2, G3, and mainly cohesive/mixed in G4.


CONCLUSIONS
According to this model, resin-based materials (Clinpro Sealant, Delton) showed better microtensile bond strength than compomer (Dyract Seal) or resin-modified glass ionomer (Fuji IILC).
Papacchini
Federica
F
Department of Dental Materials and Restorative Dentistry, University of Siena, Policlinico Le Scotte Viale Bracci, Siena, Italy.
Cury
Alvaro H
AH
Goracci
Cecilia
C
Chieffi
Nicoletta
N
Tay
Franklin R
FR
Polimeni
Antonella
A
Ferrari
Marco
M
D000134:Acid Etching, Dental; D000180:Acrylic Resins / Q000737:chemistry; D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D020770:Compomers / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure*; D005899:Glass Ionomer Cements / Q000737:chemistry; D007180:Incisor; D008298:Maleates / Q000737:chemistry; D008422:Materials Testing; D023421:Models, Animal; D063065:Organophosphonates / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry; D010895:Pit and Fissure Sealants / Q000737:chemistry*; D011897:Random Allocation; D012117:Resins, Synthetic / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
D000180:Acrylic Resins; C500418:Clinpro Sealant; D020770:Compomers; D003188:Composite Resins; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D008298:Maleates; D063065:Organophosphonates; D010756:Phosphoric Acids; D010895:Pit and Fissure Sealants; D012117:Resins, Synthetic; C454540:Scotchbond etchant; C496147:dyract seal; C444699:non-rinse conditioner; D017438:Bisphenol A-Glycidyl Methacrylate; C006903:carbopol 940; C030242:phosphoric acid