A Randomised Controlled Trial of Tooth Mousse to Remineralise Post-orthodontic Treatment White Spot Lesions

The study will be run in the Orthodontic departments of Dundee Dental School and Perth Royal Infirmary, both in NHS Tayside. The investigators will recruit a total of 80 participants to the study. Clinicians within the orthodontic departments will determine when a patient could be a potential participant of the study, and one visit prior to debonding of their brace, the treating clinician will discuss the study with the potential participant. If they are interested in finding out more, the clinician will issue the potential participant with the appropriate PIL. There will be a PIL for potential participants over sixteen years old, and separate PILs for those aged twelve to sixteen years old, under twelve years old, and for parents/guardians of potential participants under sixteen years old.. The clinician will then inform the PI/SI that a PIL and supporting documentation has been issued. There will be a potential participant referral form, which can be completed to aid the transfer of information to the PI/SI. Potential participants under twelve years old will be advised that a parent or guardian must attend with them for the debond appointment, when written informed consent (IC) will be sought from the parents/guardians by the Investigators of the study.

Once IC has been obtained, resting and stimulated salivary flow rate will be measured by the Investigators or delegated member of the research team using a Saliva-Check Buffer kit (GC Corp, Leuven, Belgium). The kit will allow observation of the quantity and viscosity of resting saliva produced in one minute, and the pH of the sample will also be tested and recorded. Participants will then chew a piece of paraffin wax for a two-minute period to produce a stimulated salivary sample. The liquid component of the sample will be measured to allow a flow rate in ml/minute to be calculated, and the pH again tested and recorded. The buffering capacity of the stimulated saliva will also be determined by challenging the saliva with varying amounts of lactic acid. As a lack of saliva would bias the results for the study due to increased caries risk, and as saliva is essential for the hydrolysis of the CPP-ACP from the TM, if the resting salivary flow rate is below 0.2ml/min, or the stimulated rate below 1.0ml/min, then the subject will be excluded from the study. Participants will then be randomly allocated to the control or the experimental group.

Each subject included in the study will have their WSLs assessed and categorised clinically using the International Caries Detection and Assessment System, (ICDASii) (International Caries Detection and Assessment System Coordinating Committee, 2009a), by ICDASii calibrated examiners. Examiner reliability will be determined by scoring extracted teeth and teeth validated by histology. Reproducibility will be measured using Kappa scores. All lesions on the buccal surfaces of teeth will be included in the study. Intra-oral digital photographs will also be taken of each participant in a reproducible manner, and the photographs analysed by two different blinded ICDASii calibrated examiners, who will be recruited to the study simply to score the clinical photographs. A colour standard (CasMaTCH; Bear medic, Tokyo) will be used to allow colour matching of the images.

The experimental group will receive TM crème to use daily. The oral and written instructions regarding crème application will be provided, indicating that the crème should be applied to all surfaces of the teeth, agitated (swished) for one minute and then retainers placed for night-time wear as per crème application protocol.

Subjects in the control group will not use any crème in their retainers, but will simply be asked to place their retainer for night-time wear.