The Effect of Propolis Mouthwash Compared to Chlorhexidine Mouthwash on Oral and Cardiovascular Health

Methods:

Participants: Adult healthy and non-smoker individuals will be recruited. The study will be approved by the Human Ethics Committee of the University of Plymouth.

Main protocol: Participants will visit the laboratory on two different occasions. At the first visit, basic anthropometrical measurements will be taken before to collect a blood (6 mL) and saliva (3 mL) samples under fasting conditions. Then, the nitrate reducing capacity of oral bacteria will be measured using a 10 mL of a free-nitrite water solution containing sodium nitrate. Participants will rinse their mouth for 5 min. Then, the mouth rinse will be collected into a sterile tube to analyse the absolute concentration of nitrite. Following this, blood pressure will be taken in triplicate on the left arm using an electronic sphygmomanometer. Then, microvascular function will be measured on the left forearm (extensor digitorum) using a hyperaemia reactive test. At the end of this visit and following a double-blind and non-cross over design participants will be allocated in one group: 1) chlorhexidine mouthwash or 2) propolis mouthwash. Participants will be given 14 tubes of 10 mL of mouthwash to rinse their mouth twice a day for a week before to return to the laboratory a week later and to undertake the same measurements.

Inclusion criteria

Healthy individuals between 18 and 50 years old

Exclusion criteria

• Smoking
• To have hypertension, dyslipidaemia, diabetes, cancer or other physiological and mental disorders
• Existing interventions affecting the oral bacteria: mouthwash, tongue scrapes
• To have taken antibiotics within the last month.
• In females, to have irregular menstrual periods, less than or greater than 28 days over the last 3 months