Comparative Evaluation of Different Teeth Whitening Agents on Extrinsic Stains: An In-Vitro Interventional Study

Tooth discolouration caused by extrinsic factors such as medications and dietary chromogens is a common aesthetic concern. While various whitening agents are available, their effectiveness may vary depending on the type of stain and formulation. Natural alternatives are gaining attention due to their potential safety and cost-effectiveness.

60 extracted permanent maxillary incisors were randomly divided into two main groups based on staining agents: iron medication and pomegranate juice (n = 30 each). Each group was further subdivided into three subgroups (n = 10) based on the whitening modality used: whitening strips, whitening gel, and a customized herbal toothpaste containing banana peel extract. Staining procedures were carried out for 15 days, followed by a 14-day whitening protocol. Colour measurements were recorded at baseline, post-staining, and post-whitening using a spectrophotometer based on the CIE Lab* system. Colour change (E) was calculated and statistically analysed using paired t-test, unpaired t-test, and ANOVA.

Both staining agents produced significant tooth discolouration, with iron causing greater staining than pomegranate juice. All whitening modalities resulted in reduction of E values; however, the herbal formulation showed the highest improvement (p value = 0.00000878*), followed by whitening strips and whitening gel. Pomegranate-induced stains demonstrated greater reversibility compared to iron-induced stains. Statistical analysis revealed significant intra-group and inter-group differences (p < 0.05).

The effectiveness of tooth-whitening agents is influenced by both stain type and treatment modality. The banana peel-based herbal formulation demonstrated promising whitening potential and may serve as a safe and effective alternative to conventional agents. Further in vivo studies are recommended to confirm these findings.