Evaluating the efficacy of curcumin in the management of oral potentially malignant disorders: a systematic review and meta-analysis

Abstract

Background: Oral potentially malignant disorders (OPMDs) not only harbour the risk of malignant transformation but can also affect patients' quality of life owing to severe symptoms. Therefore, there is an urgent need for therapeutic strategies to improve patients' quality of life. The objective of this meta-analysis was to comprehensively assess the efficacy of curcumin in the management of OPMDs.

Methods: PubMed, Embase, the Cochrane Library, and Web of Science were searched for clinical trials evaluating the efficacy of curcumin in the treatment of OPMDs from inception until March 2024. RevMan 5.4 software was used to perform statistical and subgroup analyses.

Results: Sixteen randomised controlled trials (1,089 patients) were selected. Curcumin exhibited comparable efficacy to conventional controls in alleviating pain (I² = 98%, P = 0.49) and improving tongue protrusion (I² = 94%, P = 0.51) in oral submucous fibrosis (OSF). Additionally, topical use of curcumin had an efficacy equivalent to that of conventional therapy in reducing pain (I² = 83%, P = 0.31) and facilitating clinical remission (I² = 67%, P = 0.38) of oral lichen planus (OLP).

Conclusion: The topical use of curcumin may palliate pain and promote clinical healing in OLP patients. Systemic curcumin can ameliorate the degree of pain and tongue protrusion in OSF. Therefore, our study suggests that curcumin could serve as an alternative treatment for managing OPMDs with lower medical toxicity than steroids, especially when steroids are not suitable. Further studies with larger sample sizes and adequate follow-up periods are required to validate our results.

Keywords: Curcumin; Oral lichen planus; Oral potentially malignant disorders; Oral submucous fibrosis; Systematic review.

Figure 1. The potentially diverse mechanisms of curcumin for managing diseases of oral cavity.

Figure 2. Flowchart for the search and selection process of this study.

Figure 3. Critical appraisal about the study quality of the included randomized controlled trials (Yadav et al., 2014; Kia et al., 2015; Hazarey, Sakrikar & Ganvir, 2015; Saran et al., 2018; Kuriakose et al., 2016; Thomas et al., 2017; Nosratzehi et al., 2018; Ara et al., 2018; Rai et al., 2019; Piyush et al., 2019; Kia et al., 2020; Nerkar Rajbhoj et al., 2021; Srivastava et al., 2021; Adhikari et al., 2022; Upadhyay et al., 2023; Namratha et al., 2023).

Figure 4. Forest plots for treatment efficacy of curcumin and active control on mouth opening of oral submucous fibrosis (Upadhyay et al., 2023; Srivastava et al., 2021; Rai et al., 2019; Piyush et al., 2019; Hazarey, Sakrikar & Ganvir, 2015; Saran et al., 2018; Yadav et al., 2014).

Figure 5. Forest plots for therapeutic efficacy of curcumin and active control on pain amelioration (A) and tongue protrusion (B) of oral submucous fibrosis (Upadhyay et al., 2023; Srivastava et al., 2021; Rai et al., 2019; Piyush et al., 2019; Hazarey, Sakrikar & Ganvir, 2015; Saran et al., 2018; Yadav et al., 2014).

Figure 6. Forest plots for managing efficacy of curcumin and active control on reducing pain (A) and clinical improvement (B) of oral lichen planus (Nosratzehi et al., 2018; Kia et al., 2015; Thomas et al., 2017).