European Journal of Molecular & Clinical Medicine ISSN 2515-8260 Volume 07, Issue 01, 2020 971 FILLERS IN COMPOSITE RESINS- RECENT ADVANCES Gajapriya M 1 , Jayalakshmi Somasundaram 2 , Geetha R V 3 1 Graduate student, Saveetha dental college, Saveetha institutes of medical and technical sciences, Saveetha university, Chennai - 600077, Tamil Nadu. 2 Chief Scientist, White Lab- Material Research Centre, Saveetha dental college and hospitals, Saveetha institute of medical and technical sciences, Saveetha university, chennai-600077, Tamilnadu, India 3 Associate professor, Department of microbiology, Saveetha dental college and hospitals, Saveetha institute of medical and technical sciences, Saveetha university, chennai-600077, Tamilnadu, India 1 jayalakshmisomasundaram@saveetha.com 2 geetha@saveetha.com ABSTRACT: Composite restorative materials represent one of the many successes of modern biomaterials research, since they replace biological tissue in both appearance and function. At least half of posterior direct restoration placements now rely on composite materials . Composite resins are a class of dental restorative materials that are a mixture of organic and inorganic components. The primary organic components are the resin, the coupling agent, the initiator and filler. Fillers play a pivotal role in the performance of composite resins. Fillers can be from a wide range of materials. Fillers in composites can be made of glasses, ceramics, metals etc. Glass fillers are usually made of crystalline silica, silicone dioxide, lithium/barium-aluminium glass, and borosilicate glass containing zinc/strontium/lithium. Ceramic fillers are made of zirconia-silica, or zirconium oxide. The development and implementation of composite dental restorative materials rely on a comprehensive understanding of each component of the composite and consideration of methods for changing each component. The aim of the review is to showcase the recent advances in composite resin fillers which have substantially improved the clinical performance of composite. KEY WORDS: Composite resin, Fillers, Nano fillers ,Recent advancements, Silane treated fillers , Sol gel fillers . INTRODUCTION: We are living in an era of esthetic dentistry where Amalgam is increasingly being replaced by aesthetic restorative materials, whose colour mimics that of natural tooth. Composite resins that can be cured using visible light are the most widely used for direct aesthetic restoration. The main composition of composite is the inorganic filler, which gives rigidity, hardness and strength to the filling, and an organic resin matrix, which provides sufficient fluidity for easy application of the composite , and allows polymerisation for rapid setting of the composite resin . In Composite resins, significant improvements have been made in their microstructure and properties. To reinforce dental composite resins, short glass fibers have been used as fillers,producing limited improvements in composite mechanical properties (Xu, 1999) . Currently available direct-filing composite resins are susceptible to fracture and hence are not recommended for use in large stress-bearing posterior restorations involving cusps.The glass fillers in composites provide only limited reinforcement because of the brittleness and low strength of glass (Masouras, Silikas and Watts, 2008) . The composite resin filler size is only one of several parameters affecting the overall properties. The filler type, shape and amount, as well as the efficient coupling of fillers and resin matrix, contribute to the material performance (Khan et al., 1992) . The combination of relatively small and varied size fillers allows a more dense packing, which in turn increases the possible filler volume-fraction of the resin- composites. Moreover, the spherical shape, especially in a mixture of different sizes, different geometrical forms facilitates incorporation of more inorganic fillers in the resin matrix . It also improves the fracture