Classification of Dental Composite Resins
Dental composite resins or cements are used for the tooth restoration. In this article, there is a brief discussion on the classification of dental composite resins and also about its history. Read on to know more.
Composite resins:Apart from the glass ionomers, the only other material that has the ability to restore aesthetics and to develop and maintain adhesion in the oral environment is the composite resin. However, their ability to adhere long term to tooth structure is limited to enamel only. Based on filler particle size and size distribution Lutz and Phillls in 1983 gave this
classification of dental composite resins.
Type I: Macro filled composite resin:This type is also known as conventional or traditional. Because of the relatively large particle size, this group exhibits a pattern of unacceptable wear both of itself and of the opposing tooth.
Type II: Micro filled composite resin:The fillers in this material are amorphous silica particles of 0.04mm average diameter. With such small filler particles they are translucent and highly aesthetic but high filler loading is difficult to achieve. The wear resistance is low and they cannot sustain a high filler loading.
Type III: Hybrid composite resin:These are also known as small particle composites. They contain a combination of macrofiller paricles with a proportion of microfiller particles and are probably the most common used composite resins. The main variation is in the proportion and distribution of the various particle sizes because this will control the ability to fill the resin and increase the percentage loading.
History of composite resin
- In 1930s Late first mentioned of the methyl methacrylates.
- In 1949, Kramer and McLean published several papers on a number of materials in this category.
- In 1954, Buonocore has showed the development of a micro mechanical adhesion to the tooth enamel simply by the acid etching the enamel for up to one minute rather than applying a thin coat of resin of a very low viscosity.
- In 1960s, Bowen has proved the value of including a variety of fillers.