All materials used in the dental setting have been approved by the Australian TGA (therapeutic goods administration)
Resin composites are commonly used routinely as a tooth-coloured filling material. There is concern from members of the public that they contain bisphenol A (BPA) which is thought to have oestrogenic effects on cells. The evidence comes from studies showing that BPA binds to oestrogen receptors in vitro. However, the oestrogenic effect of BPA is 1000-fold less potent than the native oestrogen hormone.
All current resin composites consist of methacrylate monomers (such as Bis-GMA) and DO NOT contain BPA. However, BPA is a synthetic chemical starting point from which all methacrylates are derived – in dentistry as well as many other plastics.
No evidence exists that dental composites have estrogenic effects in vitro or invivo.
Dental ceramics are very chemically inert materials and remain stable over very long periods of time. They therefore have excellent biocompatibility.
They furthermore exhibit excellent flexure strength, fracture toughness, wear resistance and colour stability. The ceramics can also be formed into precise shape to replace missing parts of a tooth.
They are an excellent material where a substantial part of a tooth is missing or for crowns.
However, in order to be held onto the tooth, the ceramic restoration has to be bonded to the tooth surface with a cement. The cement in some cases has to be a resin cement in order to provide the best adhesion. Resin cements have chemical similarities to resin composites which have been described above.
Reference: Phillips’ Science of Dental Materials, Kenneth J. Anusavice 2007.