The specific objectives of this clinical trial are to evaluate and compare the oral health
status on gingivitis and plaque control in a standardised manner between Salvadora persica
toothbrush and Salvadora persica chewing stick usage, to investigate the clinical efficiency
of Salvadora persica toothbrush and Salvadora persica chewing stick on plaque removal in
comparison with standard toothbrush, and to assess the patient-related outcome of Salvadora
persica on a short-term use. A 20% drop out rate is to be expected.
Convenience sampling will be used in this study involving non-dental students of the National
University of Malaysia Kuala Lumpur Campus. They are within the radius of the study site
therefore are easy to obtain. Their manual dexterity and attitude towards oral health are the
critical basis needed to maintain proper oral cleanliness, hence justified this
non-probability sampling method selected.
The sample size calculation formula will be devised from a pilot study, which will primarily
be conducted first involving five participants on each arm who are selected by a convenience
sampling. The mean and standard deviation of two clinical parameters; Gingival Index and
Plaque Index of the three groups assigned will be calculated. A confidence level of 95% with
margin of error of 0.5 will be set to calculate the appropriate sample size for this study.
The calculated sample size will be raised to the nearest 5 e.g. 23 will be increased to 25,
to improve the validity of the study.
Prior to the participants' recruitment, the information sheet and the consent forms will be
distributed. Enough time will be given for them to read and understand the study protocol
before they agree to participate in this study. Those who give a consent to involve in the
study will be enrolled as the participants. The principal investigator must ensure the
participants understand the benefits and risks of the study. This information will be
conveyed in an objective manner and any queries from the participants will be answered
truthfully. The participants will have the right to refuse in participating in this study.
In this study, one principal examiner will be involved for the clinical evaluations. Prior to
the initiation of the study, the examiner will be calibrated to measure the clinical
parameters of periodontal attachment level, Plaque Index, and Gingival Index against another
researcher who will act as a benchmark. For the assessment of intra-examiner reliability,
these three clinical parameters will be recorded on five non-dental students who are not
participating in this study, under the same circumstances with similar patient positioning,
light positioning, and instruments. A weighted kappa score will be used to calculate the
strength of agreement for both inter-examiner and intra-examiner reliability. An agreement is
achieved when the values are >0.8.
The clinical protocol will be conducted over a five-week period, with a total of 4 clinical
appointments performed throughout the study. In appointment 1 (baseline period), all subjects
will be undergoing a clinical examination prior to participating in the study. Subjects will
also be interviewed using a structured questionnaire to assess their oral hygiene habits i.e.
frequency and methods of toothbrushing, frequency of dental visits, as well as history of
adjunct oral hygiene aid e.g. floss, and mouthwash. To ensure that all included subjects
received the same standard of care, all participants will receive professional dental
cleaning consisting of scaling and polishing during the first visit.
During appointment 2 (pre-intervention period), the proper technique of using the designated
standard and the new miswak toothbrushes, as well as miswak chewing sticks will be explained
both verbally and visually using models to each participant accordingly by another trained
dentist who is blinded to the study protocol. In addition, all subjects received written
instructions with coloured pictures demonstrating the modified bass technique for tooth
brushing. Subjects who are selected to use miswak chewing stick will be given a sheet of
written instructions demonstrating the proper preparation and preservation techniques of
miswak chewing stick. It is very crucial that the participants are reminded to avoid using
other means of cleaning devices, dentifrices, or adjuncts for the following three weeks of
the study. Participants are also encouraged to seek for oral hygiene reinforcement wherever
they feel the need to do so throughout the study period. At this visit, participants will
also be asked to answer the pre-intervention S-OHIP questionnaires in front of an
interviewer, which has also been validated both in English and Malay versions.
Appointment 3 is one-week post-intervention while appointment 4 will be three weeks
post-intervention. In these visits, clinical examination will be carried out and assessment
of any adverse effects of oral hygiene tools used will be taken. At final visit (appointment
4), participants will be asked to answer the post-intervention S-OHIP questionnaires in front
of an interviewer.
Statistical analysis will be performed using the Statistical Package for Social Sciences
(SPSS) version 26 (SPSS Inc., Chicago, IL, USA). For the primary outcomes measure, the values
for Plaque Index and Gingival Index will be expressed as mean ± standard deviation. These
parametric variables will be analysed using Kruskal-Wallis test to determine whether
significant differences exist between the three independent groups from baseline to
pre-intervention, and from pre-intervention to first and third week of analysis of
post-intervention. Statistical significance will be set at the 95% confidence level (α=0.05)
for hypothesis testing. Post-hoc tests for multiple comparison of significant mean
differences between groups at specific time intervals will be performed with either
Dunn-Bonferroni Test (less statistical powerful and conservative) or several Mann-Whitney U
Test (inflation of Type I error), with the understanding of both test limitations. For the
secondary outcome measures, frequencies and percentages will be used to describe the
distribution of responses for each question in OHIP-14 questionnaires. Depending on the
distribution the data later, independent sample t-test/ANOVA or the
Mann-Whitney/Kruskal-Wallis tests will be used to assess the median OHIP-14 scores based on
sample characteristics, oral hygiene habits/practices and oral status. Meanwhile, the
comparisons of all groups for the presence and frequency of both objective and subjective
adverse reactions (nominal values) will be tested with Chi-Square or Fisher's exact test
where appropriate. Analysis of the subjective and objectives adverse events sessions will be
done using McNemar test.