Nine-year evaluation of a polyacid-modified resin composite/resin composite open sandwich technique in Class II cavities

Microleakage of Silorane-based Resin Composite in Comparison with Methacrylate-based Composite in Class II Open Sandwich Restorations: An in vitro Study

“…17 In the present study, use of reflective wedge and modified transparent matrix may have lead to the attenuation of the light intensity thus decreasing the contraction stresses and improving the adaptation. 17 Kays et al (1991) 25 showed that polymerization is dependent on the matrix band and wand positioning during polymerization. Curing light intensity in the most apical portion of class II cavity with cervical margins in cementum may not be sufficient if a metal matrix is used.…”

“…Debonding at the restorative tooth interface is caused by polymerization shrinkage stress in the resin matrix which may result in microleakage further recurrent caries and finally pulpitis. [15][16][17] Several alternative clinical techniques have been introduced to reduce the stress-related problems in class II cavities, among these composite laminated RMGIC or sandwich technique has proven to be effective. Its effectiveness is due to the intrinsic porosity of the cement leading to reduced stress.…”

Longevity of resin composite restorations

“…Class II restorations ranged from 58.3 % to 100 % in 9 clinical trials [8,10,12,15,[17][18][19][20][21].…”

“…For Class I and II restorations, caries was the dominant failure reason in four articles [8,10,20,31], restoration fracture exceeded 50% in one paper [18], and caries and fracture were the main reasons for failure in 6 studies [11,[15][16][17]29,33]. Opdam et al [30] reported an interesting result that the dominant reason changed with restorative techniques; fracture for the cervical lining 'sandwich' technique, and caries for a total-etch technique.…”

“…Lindberg et al [20] indicated no significant differences in 9-year survival rates of Class II restorations between hybrid resin composite restorations and open sandwich restorations, in which a polyacid-modified resin composite was placed as first layer in the cervical part of the cavity and following layers were placed with a resin composite. By contrast, Opdam et al [30] reported that a total-etch technique showed a significantly higher 9-year survival rate of…”