Another clinical study found that a gel containing 10% L. sidoides essential oil was not a good antiplaque agent.22. This study used a 21-day partial-mouth experimental model of gingivitis, in which the test gel was placed undiluted on a toothshield. It is possible that solubilization in saliva or Volasertib buy the mechanical action of a toothbrush may be necessary for an antibacterial effect to occur,13,22 which could explain the difference between this and the present study. We might also infer that, in our trial, tooth brushing released the volatile active components from the test gel, thus enabling these compounds to exert their biological actions. This study did not test the bioavailability or half-life of L. sidoides essential oil in the formulated gel.
By inference, a study showed that, after a single oral dose, thymol can be detected for 24 h in urine and 41 h in plasma, which shows its high systemic availability in humans.30 Moreover, use of L. sidoides essential oil did not induce any significant acute toxicological changes as evaluated by biochemical or hematological parameters, and this product is considered safe for use in vivo.19 The composition of L. sidoides essential oil was similar to that reported in other studies, with the phenolic compounds thymol and carvacrol being the major constituents.18,19 These volatile oils constitute a group of plant secondary metabolites that are best obtained through hydrodistillation and have potent antimicrobial activity, as has been well documented in the literature.
10,18,19,28 Thymol and carvacrol have a similar molecular formula (C10H14O), with only a minor structural difference in the position of the hydroxyl group.18 The antimicrobial action of these compounds is attributed to their phenolic character and is similar to that of eugenol. Its antimicrobial action occurs at the cell membrane level and is attributed to cellular lipid changes, loss of intracellular material, and inhibition of nucleic acid synthesis.31 These data support the antiplaque effect of L. sidoides found in the present trial and are in agreement with other studies that investigated agents with similar compounds.10,18,20,28 The test groups showed significant reductions on gingivitis at the end of the trial (LS, 40%; CLX, 52%); this is consistent with previous studies.
10,21 Nevertheless, this percent difference was Carfilzomib not significant, showing that LS had a potential similar to chlorhexidine as an antigingivitis agent. In spite of insufficient data in the literature about the anti-inflammatory action of L. sidoides preparations, this property has been reported previously. 10,21,22 This anti-inflammatory action could be due an indirect action on plaque reduction or to a direct effect on the cyclooxygenase cycle (COX-2).22 Similarly to those found in other herbal products, the flavonoids contained in L.