Successful endodontic therapy hinges on the effective elimination of microorganisms from the root canal system, particularly in cases involving infected root canals. Despite mechanical instrumentation and irrigation, complete disinfection remains a challenge due to the complex anatomy of the root canal and the presence of resistant microbial biofilms. As a result, intracanal medicaments are employed to enhance microbial control between treatment sessions.

Doxycycline, a broad-spectrum, semi-synthetic tetracycline antibiotic, has emerged as a promising intracanal medicament due to its potent antimicrobial activity, substantivity, and anti-collagenase properties. Unlike calcium hydroxide, doxycycline is effective against a wide range of both aerobic and anaerobic bacteria and demonstrates superior penetration into dentinal tubules. Moreover, its capacity to inhibit matrix metalloproteinases contributes to the preservation of periapical tissues and supports the healing process. When used within the canal, doxycycline not only targets a broad range of endodontic pathogens but also aids in the preservation of dentinal collagen, promoting periapical healing.

Preliminary studies also suggest good biocompatibility when used in endodontic settings. While promising, further clinical research is needed to establish standardized protocols for its use. Diclofenac’s combined anti-inflammatory, antimicrobial, and analgesic properties make it a valuable candidate for improving outcomes in root canal therapy.