Table 4.

Studies related to the use of herbal medicine for removal of smear layer.

Herbal Material	Characteristics	References
Green tea extract	➢Higher action against a broader range of microorganisms ➢A good chelating agent	[51]
Neem leaf extract	➢Presence of flavonoids and acid metabolites ➢The highest amount of smear layer removal	[52]
Chitosan	➢Acts on an inorganic portion of smear layer ➢Effectively remove smear layer from apical and middle areas of root canal	[50]
Oregano extract solution	➢Have the same effect as NaOCl in removing the smear layer ➢Strong antibacterial	[53]
Triphala	➢More effective in the removal of smear layer when compared to distilled water	[54]
Morinda citrifolia juice	➢Effectively removes smear layer when used with 6% of concentration with pH 3.5 ➢Contains mild acidic action, which has a chelating effect	[55]
Matricaria recutita extract	➢Most commonly used herbal medicine ➢Contains acid, which helps in removing the smear layer	[56]
Noni juice, citrus and carbonic acid juice	➢Chelating effect better than EDTA when irrigated for 30 min ➢Effective removal of smear layer	[57]
Salvadora persica (Miswak)	➢Promising herbal medication for the removal of smear layer	[58]