A review of the effects of formaldehyde release from endodontic materials

Abstract

Formaldehyde is present in most living cells and the environment. In dentistry, patients may be exposed to formaldehyde through the use of several endodontic materials (e.g. AH 26) and during formocresol pulpotomies. This review outlines how the human body reacts to formaldehyde exposure, how recent data has relooked at the issue of carcinogenicity and leukaemia associated with formaldehyde, and whether it is possible to quantify the amount of formaldehyde produced by endodontic cements. The review analyses the way formaldehyde is produced from epoxy resins and addresses the question of whether the amount of formaldehyde from endodontic cements is large enough to override the body's ability to deal with its own endogenous levels of formaldehyde and should the amount of formaldehyde produced be a concern.

BiodentineTM versus formocresol pulpotomy technique in primary molars: a 12–month randomized controlled clinical trial

“…Several studies have been done to investigate the risk of exposure to formocresol because it has mutagenic, toxic and carcinogenic risks in humans [3–5]. Due to this, many medicaments have been prepared, examined and systemized as possible replacements for formocresol [6].…”

Rheological Characterization as an Alternative Method to Indentation for Determining the Setting Time of Restorative and Endodontic Cements

“…This is in contrast to ProRoot MTA, where both calcium silicates and calcium aluminates react with water to creating a matrix [ 35 ]. The setting reaction of AH 26 relies on the slow polymerization of epoxy resin with bisphenols [ 22 ]. In contrast, AH Plus, a chemically related material, shows a lower initial gradient.…”

“…The powder contains bismuth oxide (as the radiopaque agent) and hexamethylenetetramine (HMT), which serves as the hardener. When mixed, the HMT crosslinks the bisphenol diglycidyl ether to produce a three-dimensional network, hence making the material set into a hard mass [ 22 ]. A related epoxy resin cement is AH Plus ® (Dentsply DeTrey, Konstanz, Germany), which is supplied as two pastes that are mixed together, with silicon oil as a carrier.…”

The extrusion of root canal cement containing paraformaldehyde into the inferior alveolar nerve canal resulting in infection and numbness

“…Root filling materials should meet several general requirements, including biocompatibility. At the same time, the aforementioned destructive effects of formaldehyde may also depend on the quantity of material used (Athanassiadis et al 2015). Formaldehyde is an extremely reactive chemical and has cytotoxic, mutagenic, carcinogenic, pro-allergenic and neurotoxic effects (Brodin et al 1982, Lovschall et al 2002.…”

“…Paraformaldehyde-containing endodontic cements can cause permanent nerve damage as a result of complete and irreversible inhibition of nerve tissue (Brodin et al 1982). At the same time, the aforementioned destructive effects of formaldehyde may also depend on the quantity of material used (Athanassiadis et al 2015). In some root canal cements, resorcinol has been added to formaldehyde formulation.…”