Efficacy of enzyme-based irrigants in endodontics

Abstract

Effective root canal therapy depends on a combination of mechanical instrumentation and chemical irrigation to eliminate bacteria, necrotic tissue, and debris from the complex anatomy of the root canal system. Traditional irrigants such as sodium hypochlorite and EDTA are widely used due to their antimicrobial properties and ability to dissolve organic and inorganic matter. However, these agents carry disadvantages including cytotoxicity, unpleasant taste, tissue irritation, and the potential to weaken dentinal structure. In response to these limitations, enzyme-based irrigants have been introduced as a biologically compatible alternative with selective action on organic components. Enzymes such as papain, bromelain, subtilisin, ficin, and keratinase act by breaking peptide bonds in denatured proteins, leading to the degradation of tissue remnants and the disruption of microbial biofilms. These irrigants have demonstrated effective smear layer modification without aggressive erosion of dentin and have shown compatibility with passive irrigation systems. Their activity under physiological pH conditions, combined with low toxicity and reduced risk of periapical irritation, makes them particularly useful in patients with open apices, complex canal morphology, or heightened sensitivity. Despite these advantages, limitations persist. Enzymatic efficiency may vary depending on tissue type, pH fluctuations, and anatomical challenges. Storage requirements, formulation stability, and compatibility with other endodontic materials remain areas of concern. Some studies have also noted incomplete tissue clearance when used as a sole irrigant. Current evidence supports their use as adjuncts rather than replacements in most clinical settings. Ongoing research is focused on improving formulation consistency, delivery mechanisms, and integration into standardized irrigation protocols. Enzyme-based irrigants present a promising evolution in endodontic disinfection strategies, offering a more tissue-friendly alternative that aligns with minimally invasive and biologically respectful treatment goals.