Influence of different restorative techniques on marginal seal of class II composite restorations

Abstract

ObjectiveTo evaluate the gingival marginal seal in class II composite restorations using different restorative techniques.Material and MethodsClass II box cavities were prepared in both proximal faces of 32 sound human third molars with gingival margins located in either enamel or dentin/cementum. Restorations were performed as follows: G1 (control): composite, conventional light curing technique; G2: composite, soft-start technique; G3: amalgam/composite association (amalcomp); and G4: resin-modified glass ionomer cement/ composite, open sandwich technique. The restored specimens were thermocycled. Epoxy resin replicas were made and coated for scanning electron microscopy examination. For microleakage evaluation, teeth were coated with nail polish and immersed in dye solution. Teeth were cut in 3 slices and dye penetration was recorded (mm), digitized and analyzed with Image Tool software. Microleakage data were analyzed statistically by non-parametric Kruskal-Wallis and Mann-Whitney tests.ResultsLeakage in enamel was lower than in dentin (p<0.001). G2 exhibited the lowest leakage values (p<0.05) in enamel margins, with no differences between the other groups. In dentin margins, groups G1 and G2 had similar behavior and both showed less leakage (p<0.05) than groups G3 and G4. SEM micrographs revealed different marginal adaptation patterns for the different techniques and for the different substrates.ConclusionThe soft-start technique showed no leakage in enamel margins and produced similar values to those of the conventional (control) technique for dentin margins.

Nanodoldurucu içeren kompozitlerin farklı ışık cihazları ile mikrosızıntı yönünden karşılaştırılması

“…Yap lan mikros z nt çal malar n n hemen hemen hepsinde dentin kenarlar nda gözlenen s z nt , mine kenarlar nda gözlenen s z nt dan daha fazlad r [11][12][13][14][15][16][17][18][19] . Bu nedenle, bu çal mada test edilecek materyallerin klinik performanslar n daha belirgin bir biçimde incelemek için S n f II, kavite taban n dentin bölgesini içine alacak ekilde preparasyonlar yap ld .…”

A Review on Marginal Deterioration of Composite Restoration

“…A proper marginal sealing is essential to improve the longitivity of composite resin restoration [8][9] [10]Marginal adaptation in composite restorations is related to some factors like type of dentin adhesive, restoration technique, band accuracy in finishing restoration. [[11]] The most of the clinical studies evaluating the performance of an adhesive system considers the C-factor .The C-factor of the cavities impairs the composite resin flowing during the polymerization shrinkage, increasing the stress over the bonding interface [12][13]Composite restoration ,stresses submitted on the restoration can disrupt the bonding and lead to the formation of gaps.…”

“…These are the most frequent reasons to replace or repair an adhesive restoration. The marginal failure of composite resin restoration is related mainly to the quality of bonding to the dental structures and the stress generated on the restoration [1] When the resin composite is bonded to tooth structure using adhesives the initial and residual polimerization stresses that are present along the cavity walls results in gap formation, micro leakage which leads to recurrent caries and pulpal irritation [2] The detrimental effect of marginal gap formation cannot be offset even with the use of flouride releasing adhesives or restorative material that prevent the demineralization along cavity margins [3] Thus only hermetic sealing of restorations guarantees clinical success [4] The accurate evaluations of margin qualities are important for identification of the risk of future failure of composite restorations. The clinical evaluation of marginal deterioration can be done using modified USPHS criteria which includes evaluation of marginal adaptation, marginal discolouration, secondary caries.…”

Secondary caries, mind the gap!

“…It is generally recommended that, if possible, the cervical margin of restorations should be located in intact enamel (Hilton et al, 1997;Ferrari et al, 1999;Summit et al, 2006;Kenyon et al, 2007). Those recommendations are based on the results of several in vitro studies, which demonstrate more microleakage when restorations have margins apical to the CEJ (Retief et al, 1992;Hasanreisoglu et al, 1996;Wibowo and Stockton, 2001;Brunton et al, 2004;da Silva et al, 2006;Campos et al, 2008;Rodrigues Junior et al, 2010). In these in vitro studies it is often claimed that microleakage is a predisposing factor in the development of secondary caries Eriksen and Pears, 1978;Campos et al, 2008) and therefore restorations with cervical margins below the CEJ are considered to have an increased risk for clinical failure due to secondary caries (Hilton et al, 1997;Summit et al, 2006;Campos et al, 2008).…”