Polymerization Efficiency of Glass-Ionomer and Resin Adhesives under Molar Bands

Abstract

Objective: To determine the degree of cure of a light-cured resin-modified glass ionomer (RMGI) under molar bands compared with a light-cured resin and a dual-cured resin. Materials and Methods: The 3 cements used were Fuji Ortho LC, Eagle Spectrum resin, and Variolink II dual-cure. Each sample was indirectly light cured for 20 seconds (10 seconds occlusally, 10 seconds cervically) under sections of molar bands, and the degree of cure was evaluated with micro-MIR FTIR spectroscopy. Results: The RMGI exhibited a significantly higher mean degree of cure (55.31%) than both of the resins (Eagle 19.23%; Variolink II, 25.42%), which did not differ significantly at ␣ ϭ .05 level of significance. Conclusion: Higher degree of conversion can be obtained from RMGIs under molar bands compared with composite resin adhesives provided the proper curing technique is used.

Effects of thermocycling on the degree of cure of two lingual retainer composites

“…In other words, any possible DC differences between the top and bottom surfaces of the cured resin were not taken into consideration. Another limitation of this research was the relatively small number of specimens per test group (n=5), although many published studies had used smaller sample sizes 2,6,17,[20][21][22] . According to many researchers that have used different indirect methods to evaluate the DC from monomer to polymer 23) , the DC for restorative resins reportedly ranged from 50% to 80%.…”

“…For prolonged use in the oral cavity, the lingual retainer composites must possess certain physical properties to ensure clinical success 5) . On this note, DC has been reported to affect various properties of dental resin composites: wear resistance 4) , hardness, surface roughness, tensile and compressive strengths, and flexural modulus 1,6,7) . It has been suggested that there is a correlation between DC and the resin formulation Received Jun 3, 2009: Accepted Sep 17, 2009 of dental restorative resins 8) .…”

Orthodontic material applications over the past century: Evolution of research methods to address clinical queries

“…In dental composite resins, this variable has been found to modulate the physical, mechanical and biological properties of the material since a poor polymer network is susceptible to release of biologically reactive substances (monomer, additives), predisposes to water absorption and swelling and hydrolytic degradation, and is associated with reduced mechanical properties. [6][7][8][9] The latter had given rise to approaches, which focused on the investigation of the phenomenon through mechanical testing with the hypothesis that since, higher degree of conversion is associated with improved mechanical properties profile of the material, evidence on the polymerization efficiency of the polymer could be extrapolated by measuring the response to various tests. However, the kinetics of degree of cure and mechanical properties at the time were not explored, and this resulted in erroneously assigning higher degree of cure in materials which presented better mechanical properties.…”

Effects of Time Delay on Degree of Conversion of Contemporary Orthodontic Band Adhesives

“…8 However, all dimethacrylate monomers exhibit considerable residual monomer in the final product, with a DC ranging from 36 to 72% under conventional irradiation conditions. 9 Rejman et al 10 found DCs of 19-55% for Fuji Ortho LC, Eagle Spectrum resin, and Variolink II. Kuappi and Combe 11 found DCs of 79-89% for Fuji Ortho LC.…”

“…6,10 Due to prolonged use in the oral cavity, the orthodontic band adhesives should have certain physical properties to ensure the best clinical performance.…”