METHODS: CINAHL, PubMed, and EBSCO Host and Science Direct databases were searched for articles related to the use of EOs and/or aromatherapy for nausea and vomiting. Only articles using English as a language of publication were included. Eligible articles included all forms of evidence (nonexperimental, experimental, case report). Interventions were limited to the use of EOs by inhalation of their vapors to treat symptoms of nausea and vomiting in various conditions regardless of age group. Studies where the intervention did not utilize EOs or were concerned with only alcohol inhalation and trials that combined the use of aromatherapy with other treatments (massage, relaxations, or acupressure) were excluded.
RESULTS: Five (5) articles met the inclusion criteria encompassing trials with 328 respondents. Their results suggest that the inhaled vapor of peppermint or ginger essential oils not only reduced the incidence and severity of nausea and vomiting but also decreased antiemetic requirements and consequently improved patient satisfaction. However, a definitive conclusion could not be drawn due to methodological flaws in the existing research articles and an acute lack of additional research in this area.
CONCLUSIONS: The existing evidence is encouraging but yet not compelling. Hence, further well-designed large trials are needed before confirmation of EOs effectiveness in treating nausea and vomiting can be strongly substantiated.
DESIGN: Here, we have investigated these individual plant extracts and its synergistic mixture (PEM) for its anti-cariogenic effect to reduce populations of single and mixed-species of Streptococcus sanguinis and Streptococcus mutans in a planktonic or/and biofilm and their others reduced virulence. Bacterial populations in the biofilm after 24 h, hydrophobic cell surface activity to n-hexadecane and pH changes at 5 min' intervals until 90 min of incubation were recorded. Total phenolic content and bioactive compounds in the crude aqueous plant extracts were analysed. Regulatory gene expressions of S. mutans adhesins genes (gtfB, gtfC, gbpB and spaP) upon treatment with PEM were investigated in planktonic and biofilm conditions.
RESULTS: All plant extracts strongly reduced S. mutans in the biofilm compared to S. sanguinis in single and mixed-species. PEM reduced S. mutans by 84% with S. sanguinis 87% in the mixed population. Psidium sp. and PEM highly reduced cell-surface hydrophobicity of the two bacteria thus reducing adherence and biofilm formation. PEM and Mangifera sp. lowered initial pH change in the mixed populations of S. sanguinis and S. mutans. PEM downregulated the S. mutans gtfB gene expression in the single species planktonic and mixed-species biofilms.
CONCLUSIONS: The effectiveness of PEM in reducing S. mutans within the biofilm, cell-surface hydrophobicity, acid production and adhesin gene (gtfB) expression in mixed-species with S. sanguinis indicates its potential as an antibacterial agent against dental caries. This is attributed to the phenolic content in the PEM.