Gingival Necrosis Caused by the use of Paraformaldehyde-Containing Paste: Case Series

Abstract

Many of the medicaments used historically in root canal treatment have been shown to be cytotoxic [1]. Toxic devitalising agents such as arsenic trioxide (As2O3), a water-soluble compound, forming arsenious acid (H3AsO4) and paraformaldehyde were commonly used in the past to devitalise inflamed pulps when effective anaesthesia could not be obtained [2]. Among these substances an important role was played by paraformaldehyde pastes. In the oral cavity paraformaldehyde agents are used both as disinfectants and to devitalise inflamed pulps when local anaesthesia is ineffective. Despite the clinical benefits paraformaldehyde is not confined to the pulp, but penetrates through dentine and is gradually released as formaldehyde. Formaldehyde released through dentine has a destructive effect on periodontal and bone tissues [3-8].