The aim of this experiment is to investigate the effect of Miswak on oral malodor and to determine whether this effect -if present- is the result of the mechanical action of Miswak or the chemical effect of its extract

The study was designed as a randomized, parallel group clinical trial with one control and two test groups. The efficacy of each modality was evaluated by comparing the oral malodor indicators before use with those after 15 minutes (masking effect) and 7 days (therapeutic effect) of use. Three indicators for oral malodor were recorded; Organoleptic scores (OLS), Self-assessment of oral malodor, and the level of volatile sulfur compounds (VSC) measured by a breath checker device.

Ethical committee approval was obtained from the research center in Riyadh Colleges of Dentistry and Pharmacy (FUGRP/2013/114) prior to conducting of the study.

Between March and December 2014, screening of volunteered 212 female dental students aged 18-35 years was carried out. Preliminary interview and clinical examinations were done for all volunteers to select the sample according to the study inclusion and exclusion criteria. To be included in the study, the participants should report that they suffered from bad oral malodor and also should have an organoleptic score of 2 or above. Total of 167 interviewed subjects were excluded from the study for not fulfilling the eligibility criteria and a final sample size of 45 volunteers who have satisfied the criteria were selected in the study. The objectives of the study were fully explained and an informed written consent was obtained to participate in the study.

One week before the baseline readings all the 45 participants received instructions to avoid eating spicy foods, garlic and onions 2 days prior to the assessment. All participants were instructed to maintain their current oral hygiene regime.

The included participants (N=45) were randomly divided into 3 groups. (Group ME): 15 participants were asked to rinse with 50% Miswak extract mouth wash (5ml) twice a day for 7 days. Each participant was given a determined volume of the mouth wash and a marked scoop for the prescribed dose. Compliance of the participants was checked by measuring the remaining volume in the bottle during the second visit.

(Group MS): 15 participants were taught and instructed to use Miswak stick twice a day for 7 days. Length of the Miswak stick was measured on the second visit to assess the compliance of the participants in using them.

(Group CH): 15 participants were taught and instructed to rinse with 5 ml of 0.2% Chlorohexidine gluconate mouth wash (Oraxine ®) twice a day for 7 days. Each participant was given a determined volume of the mouth wash and a marked scoop for the prescribed dose. Compliance of the participants was checked by measuring the remaining volume in the bottle during the second visit.

To prepare the Miswak extract, a group of fresh Miswak sticks were collected from the local market and chopped into very small pieces. The sticks were then allowed to dry in room temperature for 2 days before they were ground into powder. To prepare the mouth wash, 10 gm of the powder was added to 100 ml of sterile distilled water and allowed to soak for another two days at a temperature of 4°C. It was then centrifuged for 15 minutes at 2000 rpm and then filtered using 0.45 μm pore size paper. The resultant solution was further diluted by distilled water by the ratio of 1:1 and used within one week.

Measurements of oral malodor indicators:

All readings were taken early in the morning one to three hours after breakfast and tooth brushing. Measurements included the following:

• Self-assessment of mouth odor
• Organoleptic scores (OLS)
• Volatile sulfur compound

Data analysis was performed using paired t-test to compare the different indicator scores before and after the use of each method. One way ANOVA was also performed to test the significance of the difference between the three methods in reducing oral malodor. A P<0.05 was accepted as the level of significance.

Inclusion Criteria:

• the participants should report that they suffered from bad oral malodor
• organoleptic score of 2 or above

Exclusion Criteria:

• smoking
• current systemic diseases or medical treatment
• active caries or any faulty restorations
• acute sinusitis or oro-pharyngeal infection
• chronic periodontitis
• pregnancy
• breast feeding
• eating very spicy food
• use of antibiotic during the last two months before the start of the study

Serious and Other [Not Including Serious] Adverse Events were not monitored/assessed.