Successful endodontic treatment is fundamentally dependent on the effective elimination of microorganisms from the root canal system. The complex anatomy of root canals, including accessory canals, fins, isthmuses, and dentinal tubules, presents a significant challenge to complete microbial eradication. Persistent intra radicular infection remains the primary cause of endodontic failure, even after thorough chemo-mechanical preparation, largely due to the survival of resistant microorganisms and biofilm formation within inaccessible areas of the canal system.¹ Conventional endodontic irrigants, such as sodium hypochlorite (NaOCl), chlorhexidine (CHX), ethylenediaminetetraacetic acid (EDTA), and hydrogen peroxide (H₂O₂), have long been employed to enhance canal disinfection; however, their clinical use is associated with several limitations, including cytotoxicity, unpleasant taste, tissue irritation, allergic reactions, and detrimental effects on dentin structure when used at higher concentrations.²

In response to these limitations, contemporary endodontic research has increasingly focused on the exploration of herbal and natural products as alternative or adjunctive antimicrobial agents. Herbal medicine, defined as the use of plant-derived preparations containing bioactive compounds, has gained considerable attention due to its biocompatibility, affordability, wide availability, and reduced incidence of adverse effects.³ Moreover, the growing global concern regarding antimicrobial resistance has further strengthened interest in phytotherapeutic agents capable of exerting antimicrobial activity without promoting resistance.⁴

Endodontic infections are characteristically polymicrobial, dominated by anaerobic and facultative anaerobic species. Among these, Enterococcus faecalis has been consistently identified as a key pathogen associated with persistent and secondary root canal infections. Its ability to survive under nutrient-deprived conditions, penetrate dentinal tubules, resist alkaline environments, and form robust biofilms contributes to its persistence despite conventional irrigation protocols.³ Biofilm-associated microorganisms exhibit significantly greater resistance to antimicrobial agents compared to their planktonic counterparts, necessitating the development of irrigants capable of disrupting biofilm architecture in addition to eliminating free-floating bacteria.¹

Multiple in-vitro and review-based studies included in the present body of literature have demonstrated that herbal agents possess substantial antimicrobial efficacy against common endodontic pathogens. Natural products, such as Azadirachta indica (neem), Ocimum sanctum (tulsi), Salvadora persica (miswak), Morinda citrifolia, Triphala, Glycyrrhiza glabra (liquorice), propolis, and green tea polyphenols, have been shown to inhibit the growth of E. faecalis, Streptococcus mutans, and Candida albicans through mechanisms, including cell wall disruption, enzyme inhibition, and interference with microbial adhesion.^3,4,5,6 Several studies have further reported that these agents demonstrate antimicrobial activity comparable to conventional irrigants when tested under laboratory conditions, particularly when higher concentrations or prolonged contact times are employed.

In addition to their antimicrobial properties, herbal products exhibit a wide range of biological effects relevant to endodontic therapy, including anti-inflammatory, antioxidant, and immunomodulatory actions. These properties contribute to a more favorable tissue response and may support periapical healing following root canal treatment. Evidence from experimental studies suggests that certain herbal compounds, such as propolis, acemannan, baicalin, and genipin, promote odontoblastic differentiation, collagen synthesis, alkaline phosphatase activity, and reparative dentin formation.² Such findings highlight the potential role of herbal agents not only in canal disinfection but also in regenerative endodontic procedures and vital pulp therapy.

The concept of “Naturodontics” has emerged to describe the integration of naturally derived materials into dental practice. Literature analyses indicate that herbal products have been investigated for multiple endodontic applications, including root canal irrigation, intracanal medication, smear layer removal, lubrication during instrumentation, enhancement of sealer properties, storage media for avulsed teeth, and pulp–dentin complex repair.⁵ These diverse applications reflect the versatility of phytotherapeutic agents and their potential to address multiple clinical objectives within a single treatment protocol.

A major advantage of herbal products lies in their favorable safety profile. Compared to conventional chemical irrigants, natural agents generally demonstrate lower cytotoxicity and reduced risk of adverse tissue reactions.⁶ Their biodegradability and minimal environmental impact further support their use in sustainable healthcare practices. Additionally, regarding antimicrobial resistance, there is currently limited and largely indirect evidence suggesting that most herbal agents are less likely to induce microbial resistance; however, this has not been comprehensively studied, and definitive conclusions cannot yet be made.

Despite encouraging laboratory evidence, the routine clinical adoption of herbal products in endodontics remains limited. A critical challenge identified across the literature is the heterogeneity in study designs, extraction methods, concentrations, and outcome assessment techniques. Many investigations are in-vitro in nature, and while they provide valuable preliminary data, their findings require validation through well-designed in vivo and randomized clinical trials.³ Furthermore, the complex chemical composition of herbal extracts, influenced by plant species, geographic origin, and processing methods, underscores the need for standardization to ensure reproducible therapeutic outcomes.

In view of the growing body of evidence supporting the antimicrobial and regenerative potential of herbal products, a comprehensive synthesis of current literature is warranted.

Therefore, the aim of this review is to critically evaluate the available evidence on the use of herbal products in endodontics, with particular emphasis on their antimicrobial efficacy, biological properties, clinical applications, limitations, and future research directions.

A study was conducted, which showed the role herbs in endodontics. RCT involves the removal of infected pulp from canals along with microorganisms to reduce infection in peri radicular and healing tissues. It also involves the use of irrigants to disinfect the root canal space; commonly used regents are CHX, NaOCl, and EDTA. The basic purpose to irrigate is reduce bacteria count. These agents are commonly used for disinfection of canals, but they showed various side effects: they are toxic and cause damage to the surrounding oral tissue. Due to these reasons different, herbal extracts are used as root canal irrigants due to its low-cost, increased shelf life, and reduced toxicity. This current study overviews the use of different plant-derived extracts as irrigants. This study focused on the use of herbal extracts like Aloe Vera, Garlic, Triphala, Green tea, orange oil, Miswak, and Glycyriza (Table 1).⁷

A study was conducted in 2020, which showed the efficacy of eucalyptus oil (Eucalyptus globulus), orange oil, and Grapefruit as a bioceramic sealer solvent. Solvent based on essential oil has been used for the removal of Gutta percha from canals. Oil-based solvents are nontoxic and more effective than conventional solvents. The study concluded that oil-based solvents show more efficacy as compared to bioceramic sealer solvent.⁸

A study was conducted in 2023 showed the efficiency of orange oil solvent, combined with disinfectants and bioactive glass, in improving the cleanliness of the root canal after endodontic Re-Rx: An in vitro study. Re-treatment of endodontics includes many complications and a doubtful prognosis due to little removal of bacteria and dentinal debris. The aim of this study is to see the effect of orange oil solvent and bioactive glass in the removal of root canal material and to reduce bacterial count during root canal retreatment; 30 single-rooted human extra incisors were collected. Access opening and shaping + cleaning were done. With suspension of Enterococcus faecalis at 37°C were injected into samples for 48 h and then filled in root canal filling space using lateral compaction technique. This study concluded additives of bioactive glass not affect the antibacterial activity of orange oil irrigant for removal of root canal filling materials.⁹

A study was conducted in 2024, which showed a comparative evaluation of the antimicrobial efficacy of various intracanal medicaments (Curcuma longa, honey, Nitrofurantoin, and Ca(OH)₂). Intracanal medicament was placed in the canal to treat infections, to decrease inflammation, and to dissolve organic and inorganic materials. Fifty central incisors were decoronated at CEJ, followed by canal preparation. The results concluded that honey showed the greatest antimicrobial efficacy among all other groups of intracanal medicaments (Table 2).¹⁰

A study was conducted in 2025 on the evaluation of guava leaves extract alone or combined with a diode laser as a root canal irrigant. Guava leaves contain a compound known as Quercetin, which shows antimicrobial properties. The aim of this study was to evaluate the antibacterial effect of guava leaves alone or in combination with a diode laser on the removal of the smear layer. It was concluded that the extract of guava leaves, followed by NaOCl, and then diode laser 980 nm, showed maximum antibacterial effect and high smear removal.¹¹

A study was conducted in 2025 on impact of photodynamic therapy in root canal disinfection and smear layer removal using phytocompound. The aim of this study was to evaluate the antibacterial properties of Psidium guajava (guava) and Citrus sinensis (sweet orange) on E. Faecalis and compare their effectiveness as irrigation solutions using photodynamic therapy (PDT). Results showed that colony forming units (CFU) were reduced more in the guava extract compared to the sweet orange extract. It was concluded that guava extract showed maximum removal of the smear layer from root canal specimens and showed a higher antibacterial effect compared to sweet orange oil.¹²

A study was conducted in 2017 with the aim of comparing the antimicrobial effect of Morinda citrifolia (MC), Triphala, and green tea polyphenols with NaOCl against E. faecalis; 60 extracted human premolar teeth were used in this study. They were infected with E. faecalis for 48 h. After 48 h, they were inoculated on blood agar plates and the bacterial population assessed by counting No. of CFU. Results showed that NaOCl is the most effective irrigant used against E. faecalis. Then Triphala showed antibacterial effects, while the minimum effect was shown by MC (Morinda citrifolia). It was concluded that the use of herbal irrigants is considered beneficial while considering several drawbacks of NaOCl as an irrigant.¹³

An in vitro study was conducted in 2019 on the influence of plant extract mixed with e-endodontic sealer on growth of oral pathogens in the root canal. The aim of this study was to compare antimicrobial effects of sealers when plant extracts were added. Three different sealers were mixed with three different herbal extracts and were evaluated against seven strains of bacteria at different time intervals using the agar diffusion test. Results showed that a significant zone of inhibition was seen in ZnO eugenol-based sealer mixed with e-Glycyrrhiza glabra, followed by ZnO eugenol-based sealer mixed with e-Tinospora cordifolia and Mimusops elengi. It was concluded that ZnO eugenol-based sealer with herbal extracts produce more zone of inhibition compared to resin-based sealer and Ca(OH)₂ along e-herbal extracts (Table 3).¹⁴

A study was conducted in 2023 on the estimation of minimum inhibitory concentration (MIC) ratio of herbal extracts against common endodontic pathogens. Herbal extracts are gaining the attention of researchers due to the presence of phytochemicals like terpenoids and phenolic compounds, which show antibacterial, antifungal, anti-inflammatory, and antioxidant properties. The MIC and minimum bactericidal concentration (MBC) of four herbal extracts, that is, lemon grass oil, basil oil, peppermint oil and hibiscus tea extract were evaluated against eight common endodontic pathogens along e-MIC: MBC/MFC ratio were evaluated. Results shows that herbal extract showed antimicrobial effect against endodontic pathogens: Basil oil and mint oil showed bacteriostatic activity against Enterococcus faecalis and Pepto streptococcus (p > 0.005). Tea extract showed bacteriostatic effect against all pathogens except Actinomyces, Lactobacilli, Staphylococcus aureus, and Fusobacterium nucleatum. Lemon grass oil showed bacteriostatic and bactericidal effect against Pepto streptococcus (p > 0.05). It was concluded that basil oil had a strong bactericidal effect, and MIC values of the tested organisms ranged from 0.2–50 µg/mL (Table 4).¹⁵

A randomized controlled clinical trial was conducted in 2024 on the effect of Curcuma longa (Turmeric) as an intracanal medicament on inter-appointment endodontic pain in patients with symptomatic irreversible pulpitis. One hundred healthy adult patients having symptomatic irreversible pulpitis (SIP) in single rooted maxillary or mandibular teeth were part of this randomized controlled, parallel, single blinded clinical trial. Data were analyzed by using Kruskal–Wallis, Mann–Whitney U, and Wilcoxon single rank tests. Statistically, no pain was observed between Ca(OH)₂, TAP, or Curcuma longa groups.¹⁶

This study highlights the use of herbal products as potential alternatives or adjuncts to conventional chemical irrigants and intracanal medicaments. The findings from the reviewed studies indicate that several plant-derived extracts possess significant antimicrobial activity against common endodontic pathogens, particularly Enterococcus faecalis, which is frequently associated with persistent root canal infections.

Herbal agents, such as Triphala, aloe vera, green tea polyphenols, guava leaf extract, Curcuma longa, honey, and essential oils, have demonstrated promising antimicrobial effects. These phytotherapeutic agents contain biologically active compounds including flavonoids, alkaloids, terpenoids, and phenolic compounds, which contribute to their antibacterial and anti-inflammatory properties. In several in-vitro investigations, herbal extracts showed antimicrobial efficacy comparable to conventional irrigants when used at appropriate concentrations and contact times.

Orange oil and eucalyptus oil have been investigated as solvents for the removal of gutta-percha during endodontic retreatment, demonstrating effectiveness with lower toxicity compared to traditional solvents. Similarly, the addition of herbal extracts such as Glycyrrhiza glabra to endodontic sealers has been shown to enhance antimicrobial activity against oral pathogens. These findings suggest that herbal agents may be utilized in multiple stages of endodontic therapy.

The review also highlights the use of herbal intracanal medicaments. Studies evaluating agents, such as Curcuma longa and honey, have reported significant antimicrobial activity and comparable clinical outcomes to conventional medications such as calcium hydroxide. In addition, the biological properties of many herbal products—including antioxidant and anti-inflammatory effects—may contribute to improved tissue healing and reduced post-operative discomfort.

Herbal agents generally demonstrate lower cytotoxicity and improved biocompatibility compared to conventional irrigants such as NaOCl. However, evidence regarding their effects on dentin microhardness, bond strength, and compatibility with calcium hydroxide or endodontic sealers remains limited. In addition, variability in formulations and the potential for allergic reactions should be considered during clinical use.

Current evidence supports the use of herbal products mainly as adjuncts rather than replacements for conventional endodontic agents. They may be beneficial in cases requiring reduced tissue irritation or improved biocompatibility; however, most available evidence is derived from in vitro studies with limited clinical validation. Therefore, clinical recommendations should be made cautiously until further high-quality trials become available.

Despite these promising findings, several limitations remain. Most available evidence is derived from laboratory-based in-vitro studies, which may not accurately replicate the complex environment of the root canal system. Variability in extraction techniques, concentrations, and experimental methodologies also makes direct comparison between studies difficult. Furthermore, the lack of standardized formulations and dosage protocols limits the clinical applicability of these agents.

A major challenge in the clinical translation of herbal products is the lack of standardization in plant sources, extraction methods, and quantification of active phytochemical components. Variations in geographic origin, harvesting conditions, and processing techniques may significantly influence antimicrobial efficacy and biocompatibility. Therefore, the development of standardized clinical-grade formulations, with consistent concentrations, quality control measures, and regulatory approval pathways, is essential before widespread integration of herbal agents into routine endodontic practice.

Therefore, while herbal products demonstrate encouraging antimicrobial and biological properties, further well-designed in vivo studies and randomized clinical trials are required to establish their safety, optimal concentrations, and long-term clinical effectiveness in endodontic practice (Table 5).

Herbal products have no doubt represented a promising area of innovation in endodontics due to their antimicrobial activity, biocompatibility, anti-inflammatory, and antioxidant properties. Such products are safe to use as root canal irrigants, intracanal medication, sealer enhancers, and retreatment solvents.

However, the majority of available evidence is based on in-vitro investigations. The absence of standardized extraction methods, concentrations, and clinical protocols remains a major challenge to their routine clinical use.

Further research in the form of well-controlled clinical trials and standardized product formulations is essential to validate the effectiveness and safety of herbal agents in endodontic therapy. With continued scientific investigation, herbal products may serve as effective adjuncts or alternatives to conventional endodontic materials in the future.