A Comparative Evaluation of Irrigants with or without Diode Laser in Removal of Smear Layer Using File Systems: A SEM-EDX Study

The success of root canal treatment relies on the effective removal of dental pulp remnants, microorganisms, and microbial toxins through chemo-mechanical debridement. During preparation, debris accumulates on the wall of the root canal creating an amorphous layer called as smear layer. It is defined as “A layer of organic and inorganic material that is created on the surface of dentin during instrumentation of the root canal. This layer consists of dentin debris, pulp tissue remnants, and potential contaminants introduced during the procedure.” During root canal shaping and cleaning, irrigation acts as an effective method in the removal of micro-organisms, their by-products and the smear layer. Agents used in the removal of smear layer are phosphoric acid, citric acid, maleic acid, ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite (NaOCl).

In root canal therapy, NaOCl solution is a widely used irrigant, responsible for its antimicrobial properties and capacity to dissolve organic tissues. Inadvertent extrusion of irrigant beyond the periapex, termed sodium hypochlorite accident, may also be the cause of endodontic flare ups. However, sodium hypochlorite is ineffective in dissolving the inorganic debris and eliminating the smear layer. Also, excessive dose can harm the periapical tissues.Various sophisticated irrigants such as Chitosan and herbal irrigants like Apple cider vinegar (ACV) along with irrigating file systems such as HyFlex CM File systems and recent XP Endo file have gained attention as potential alternatives to synthetic chemicals, primarily to mitigate the negative effects linked to synthetic irrigants.Chitosan is polysaccharide in nature obtained from the deacetylation of chitin from the seashell of crustaceans and shrimps. It possesses antibacterial effect and high

chelation ability which dissolves the inorganic parts of smear layers. Henceforth, considered as a final irrigation solution.Herbal irrigants such as Apple Cider Vinegar utilizes chemo-mechanical process to eliminate microorganisms, dissolve necrotic tissue, and remove the smear layer. It also offers the advantages of being a biocompatible and eco-friendly alternative to conventional irrigants.

HyFlex CM NiTi file is an advanced endodontic instrument manufactured through a unique process i.e. Controlled Memory, ensuring extreme flexibility for superior canal tracking. It closely adapts to the canal anatomy, reducing the risk of ledging, transportation or perforation and can be pre-bent like stainless steel instruments. After heat treatment, they restore their form, providing up to 300% more fracture resistance. Newer XP Endo file is a continuous rotation file, effective in debris and smear layer removal as it facilitates irrigation which has ability in biofilm removal from the main canal as well as deep, narrow apical groove. Furthermore, Diode LASER is employed in root canal irrigation systems for its exceptional disinfection properties. After the preparation and rinsing of the root canal, it is used as an adjunct to conventional methods. With its ability to penetrate deep into dentinal tubules and target microorganisms in inaccessible areas, it also enhances disinfection and leads to better long-term prognosis.