Current status of whitening agents and enzymes in Dentistry

Abstract

This study reviews the knowledge on the use of conventional dental whitening and the use of enzymes as a new approach in bleaching. A review of the literature was based on academic articles and on patents related to the use of enzymes in dental bleaching. Tooth whitening techniques used nowadays are well reported in the literature, and its mechanism of action consists of an oxidoreduction reaction with the release of free radicals. The great instability of radicals, when in contact with the tissues, promotes oxidation and reduction in the size of the pigment chains incorporated into them. These pigments are eventually broken down into smaller and smaller molecular chains and end up being diffused from the dental structure. In turn, the use of enzymes aimed at tooth whitening can be a less harmful alternative to the tooth because their specificity regarding the substrate makes them of great interest to perform specific reactions, reducing collateral effects. The use of proteolytic enzymes and oxidoreductases paired with the application of peroxides, can be a promising alternative for obtaining even better results in the dental bleaching process.

Bright Smiles, Hidden Dangers: A Literature Review on the Potential Side Effects of Peroxide Based Over-The-Counter Teeth Whitening Treatments

“…These radicals exhibit high instability upon contact with target tissues, causing oxidation and reduction of pigment chains bound to them. As a result, these pigments undergo cleavage into progressively smaller molecular chains, ultimately dispersing from the tooth structure or indirectly enhancing light absorption due to reduced chain size, thereby creating the appearance of whiter teeth [8,10]. Hydrogen peroxide (H2O2) is a clear liquid with a slightly denser consistency than water and a molecular weight of 34.01 g/mol.…”

“…Peroxides release highly reactive free radicals that oxidize organic chromophores, which are the small molecules responsible for tooth discoloration from substances like coffee, red wine, or tea. As a result of this oxidation process, these molecules are broken down into smaller compounds that absorb fewer wavelengths of visible light, leading to a lighter appearance of the teeth [7,8]. Tooth whitening using peroxide-based agents is commonly regarded as a safe and efficient procedure.…”

“…Yet, there remains uncertainty regarding whether bleaching procedures with peroxides cause actual enamel damage. Additionally, studies have indicated that tooth whitening with peroxides can induce changes in the enamel surface [7,8,9]. Generally, there is limited evidence regarding the effectiveness and safety of over-the-counter (OTC) teethwhitening agents, raising concerns as these products are widely used by individuals seeking to improve tooth color without being fully aware of potential risks.…”