Packable composites

Fiowable composites, by contrast, have lower filler loadings and a higher proportion of low viscosity monomers. They are thus more readily able to flow into surface irregularities on the prepared and bonded tooth surface. Consequently, they complete the restoration in such a way that httle if any unoccupied space remains. By comparison with packable composites, however, they shrink more on setting [43]. 

G. Abbass, G.J. Fleming, E. Harrington, A.C. Shorthall, F.J. Burke, Cuspal movement and microleakage in premolar teeth restored with a packable composite cured in bulk or in increments, J. Dent. 31 (2003) 437 444. 

Y.Z. Bayindir, M. Yildis, F. Bayindir, The effect of soft-start polymerization on surface hardness of two packable composites. Dent. Mater. J. 22 (2003) 610-616. 

J. Manhaart, K.-H. Kunzehnann, H.Y. Chen, R. Hickel, Mechanical properties and wear behaviour of light-cured packable composite resins, Dent. Mater. 16 (2000) 33-40. 

Resin composites can be classified according to filler particles as fine-particle, hybrid, microhybrid and microfilled other classifications such as flowable or packable are related to their manipulation [1-3]. Quartz and glass (several types) fillers in fine-particle composites have sizes of about 0.5 to 3 pm. Microfilled and hybrid composites contain colloidal silica particles of 0.01 to 0.02 pm diameter incorporated in the polymer matrix. The microfilled composites also contain these submicron particles in groimd 10 to 20 pm filler particles of the polymerized oligomers. The filler volume fraction for composite products varies widely from about 20% to 70%. Clinical selection of composites depends upon strength, wear resistance and esthetics needed for the particular tooth restoration. 

F.B. de Souza, R.P. Guimaraes, C.H. Silva, A clinical evaluation of packable and microhybrid resin composite restorations one-year report, Quintessence Int. 36 (2005) 41-48. 

A number of classification systems have been proposed to describe restorative composites. These materials may be distinguished by their consistency, and classified as flowable, conventional and packable [26] but the most used classification system is based upon filler particle size. As restorative composites have evolved, the size of filler particles and their size distribution have been changed in an attempt to achieve the best possible mechanical properties while maintaining esthetics. 

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