Bond strengths to bovine enamel: assessment of three glass ionomer cements

Marina Lara SÓRIA, Luciane Macedo de MENEZES, Hugo Mitsuo Silva OSHIMA, Susana M. Deon RIZZATTO

The present “in vitro” study was conducted to assess the shear bond strength of orthodontic brackets bonded to bovine enamel obtained with three different light cured ionomeric bonding agents. Forty-eight permanent bovine incisors were sectioned, included in acrylic resin and randomly allocated to three groups: Group I, in which the brackets were cemented with powder/liquid Ortho Glass LC (DFL); Group II, cemented with paste/paste Ortho Glass PLC (DFL) and; Group III, cemented with powder/liquid Fuji Ortho LC (GC). The enamel surfaces were etched with 37% phosphoric acid for 60 seconds and the brackets (Morelli) were bounded according to each manufacturer’s instructions. After bounding, the specimens stayed 1 hour at 37ºC temperature and 100% moisture content atmosphere and then 23 hours in distilled water at 37ºC. The bonded surfaces were then submitted to shear strength tests at a rate of 0,5mm/minute by a universal test machine (Emic DL2000). The results showed that between Group I and II there was no signiicant statistical difference (p<0,05) but signiicant differences were found between Group III and I and between Group III and II. It was also concluded that the three cements analyzed produced bound capacities compatible to the clinical necessity, although Fuji Ortho LC had presented mean bond strength lower than the other two cements tested. No differences were found for ARI index among the groups.

Keywords: Bond strength. Glass ionomer cement. Bonding in orthodontics.

Saturday, December 28, 2024 23:03